glacial acetic acid #materials #video #toread, part 2, where he actually does the reaction.
on 02026-09-15#materials for #flying rockets to #space
on 02026-09-06#Materials #video about “scagliola” and other forms of fake marble rock for architecture. #toread
on 02026-08-25#CodysLab #video on #mining magnetite #materials efficiently. First he throws magnetite-bearing dirt with a shovel through a screen into a fan air current to remove gravel and dried grass. Then he lets it trickle out of a hole cut in the bottom of a 20-liter bucket onto a big magnet, which redirects the magnetite to the side into another bucket, while the non-magnetic sand bounces off in the other direction; it takes 8 minutes to process 20 liters. In a day and a half of work he collects 800 “pounds” of 90% thermite.
on 02026-08-24#CodysLab #video converting urine to 202 grams of potassium nitrate fertilizer #materials, precipitating Ca(NO₃)₂ (having previously replaced some ammonia with CaO) with K₂CO₃. Demonstrates recrystallization in water to separate NaCl. Also uses a paper towel at one point to filter solids out of his nitrate solution.
on 02026-08-24#public TV #video from #ACS-Reactions on extracting citric acid #materials from lemons and by fermenting with Aspergillus niger from a moldy onion, after first starting it in potato dextrose broth, then removing the metal ions from molasses with potassium ferrocyanide, and then feeding the A. niger. "ChemThug" tried using a calcium hydroxide solution to precipitate any oxalate in the mold menstruum, and didn’t find any, although I’m not clear how that would distinguish citric acid from oxalic acid.
So again he adds NaOH to the lemon juice, turning it orange, and then boils the stuff, which turns it brown. Again he precipitates calcium citrate from the slightly basic sodium citrate with calcium chloride (the heating part here is omitted), filtering it through coffee filters (using vacuum filtration) and then oven-drying the precipitate.
For the mold broth he adds calcium hydroxide directly instead of going through the sodium stage, then boils the stuff. Again, to convert calcium citrate to citric acid, he adds sulfuric acid. But his final product wasn’t citric acid, or any acid, because it didn’t make baking soda fizz. So he tried again. Interestingly, he’s using a hand pump for the vacuum filtration.
Then he tries to salt out the citric acid from water solution with acetone.
I wonder if the NileRed video product was actually citric acid after all?
on 02026-08-24#NileRed #video on extracting citric acid #materials from lemons. But, uh, he used lye, sulfuric acid, hydrochloric acid, and calcium chloride to do it. So I’m guessing he’s going to precipitate the citric acid with the calcium citrate, wash it, then acidulate it with the hydrochloric acid? But then you have some unknown hydrochloric and citric acid in solution, plus calcium chloride. You can simpify this to just the acids by precipitating the calcium chloride with the sulfuric acid, but then you have super annoying calcium sulfate, and you still have to separate the hydrochloric acid, which I guess you could just boil off. But then what is the lye for? Let’s see.
Oh, he says he’s not going to actually use the hydochloric acid, so I guess he’s just going to acidulate the calcium citrate with the sulfuric acid, leaving insoluble calcium sulfate and citric and sulfuric acids, but then how do you separate those?
He got 458g of lemon juice (450mℓ) with a pH of 2–3 and then started adding lye to raise the pH to 8–9, which is not at all what I expected; that’s going to give sodium citrate, which is water-soluble, not a calcium-citrate precipitate. He says to fully neutralize an acidic proton, take the pH two points above its pKa, so 8.4 to neutralize the third citric-acid proton (pKa = 6.40); at this point the lemon juice is turning orange. He found that gravity filtration with coffee filters worked better than vacuum filtration because of the lemon pulp, because it’s easier to replace the clogged filters with fresh ones. Then he added the calcium chloride (28.5g dissolved in 70mℓ of distilled water) to the slightly basic solution, which I thought would immediately precipitate calcium citrate, but which needed to be heated to boiling to do so; then it settled, and he vacuum-filtered it and washed it three times with hot water, getting 77g of calcium citrate tetrahydrate. Then he added 20.9mℓ 98% sulfuric acid dissolved in 200mℓ of water; he uses a slight excess of the citrate to ensure that the sulfuric acid is fully consumed, so that the calcium sulfate waste product is contaminated with a bit of calcium citrate, rather than the citric acid desired product being contaminated with a bit of sulfuric acid. He commented that the vacuum filtering process was “kind of slow”, which is a lot less hassle than filtering calcium sulfate usually is. So then he evaporated the water from the 350mℓ of citric acid filtrate at 70°–80° with strong stirring, where I was expecting him to boil it; on reduction to about 70mℓ, he filtered it through a coffee filter to remove a precipitate he thought was calcium citrate that had remained dissolved. On gradual evaporation at room temperature for a couple of weeks, it crystallized; some “viscous brown goop” was left as a supernatant, presumably containing some kind of impurities. Also, he thinks that some of the crystals aren’t citric acid. But he got 18.1g of a theoretical yield of 21.9g.
on 02026-08-24Tricaprylin is a medium-chain triglyceride with three caprylic acid (octanoin) residues, weighing 470 daltons. #materials
on 02026-08-19> In 1787 painter and biographer Albert Christoph Dies swallowed, by accident, approximately 3⁄4 ounce (20 g) of lead acetate. His recovery from this poison was slow and incomplete. He lived with illnesses until his death in 1822.[18][19]
on 02026-08-14Apparently cocamide monoethanolamine (cocamide MEA) is still in use as a component of #detergents, as described in Richardson’s 01942 patent. #materials
on 02026-08-14Okay but actually this 01942 US #patent 2,383,737 by Albert S. Richardson at Procter & Gamble says you can greatly improve #detergents like sodium lauryl sulfate (“water-soluble salts of (...) alkyl sulfuric acids, (...)”) with things like cocamide DEA (“These compounds are the ethanolamides and glycerolamides of fatty acids having twelve [lauryl] to fourteen [myristyl] carbon atoms in the acyl radical,”) which he specifically points out as being easily made from coconut oil or palm kernel oil. Oh, but looking at his molecular diagrams, actually he’s only talking about monoethanolamines and monoglycerolamines. #materials
on 02026-08-14An 01956 US #patent claiming adding “higher fatty acid amide of monisopropanolamine” as “synergistic agents” to sodium lauryl sulfate and the like. I think this is closely related to the “cocamidopropyl betaine” commonly seen in the ingredients lists of #detergents; he calls it “the coconut fatty acid amide of isopropanolamine”, and CAPB is indeed a coconut fatty acid amide. Although apparently cocamidopropyl betaine is a replacement for cocamide DEA (cocamide diethanolamine, which is mostly lauramide DEA), which is possibly carcinogenic? Which seems likely to have been a replacement for cocamide isopropanolamine. Or maybe cocamide DEA was already in use, and he was just patenting an alternative he thought was better but which didn’t catch on. #materials
on 02026-08-14An 02020 Japanese #patent by Procter & Gamble explaining how to formulate a hand dishwashing liquid detergent that works better when you apply it directly to grease spots on your dishes without making the detergent look cloudy. They suggest 15% to 35% surfactants, 50% to 75% water, pH from 7.5 to 10 at 10% dilution, 500 to 1500 mPa·s viscosity, with 60% to 90% of the surfactant being an anionic surfactant, especially a mix of sodium lauryl sulfate and sodium laureth sulfate (0.5 to 0.9 degree of ethyoxylation). They claim that replacing something like 30% or 40% of the lauryl (dodecyl) chains with tridecyl chains is better. They say it’s good to include 2% to 10% by weight of a “co-surfactant”, preferably an “amine oxide”, which I think is a quaternium. #detergents #materials
on 02026-08-14#video on #manufacturing smoky quartz or amethyst #materials from quartz using an electron beam
on 02026-08-12#Witchcraft-and-Alchemy #video about #bootstrapping thinner aluminum #foil material for a ribbon microphone, noting that the usual stuff is about 10μm, testing with a micrometer, while ribbon-microphone #sensors are ideally 1.5–3μm. He reduces the thickness of household foil by etching the foil with NaOH #materials, 4g dissolved in 200mℓ of water (½ molar, he says), which evidently thins the foil fairly evenly. He glued foil to some plastic roundrects to hold it in place during the process. There’s a point where the foil becomes a very fine mesh, some time before being ripped apart by the hydrogen bubbles after about half an hour. He did a 4-liter test to try to hold temperature more constant. I suspect you could get smoother dissolution with the proper regime of #electrolysis, reducing asperities, but he didn’t try that. For thickness measurement, he did the same repeated-folding-in-half thing that I did, but with a micrometer instead of calipers or a ruler to measure the result. He says some of the foil had “the structural integrity of a wet paper towel,” making the process more difficult. The thinnest acts like gold leaf, sticking to his tweezers. The data shows a linear decline in thickness from 10μm at 5 minutes to 0 at 40 minutes, with a 35-minute sample being 2.2μm thick.
So he made some more samples; he tried to etch them for 32 minutes (before a citric-acid stop bath and water rinse) but they fell apart at 25 minutes.
In order to compensate for unknown temperature and agitation variations, he decided to measure the foil’s resistance during the etch process with a constant current. For #metrology, he amplifies the voltage drop across the foil with a differential-to-single-ended converter based on a LM833 dual op-amp #electronics, with an LM317 set up as a 100mA constant-current source, and a couple of relays set up to reverse the current direction through the foil to eliminate any offset errors, including from any unintended galvanic cells. Also he used an angle grinder to cut some blank PCB into a four-wire Kelvin probe so he’s only measuring the resistance of the foil itself, not the resistance of the copper leading down to the foil. The copper is painted black, presumably to protect it from the NaOH. And he’s using something like a Black Pill to record the data.
The 10μm foil is about 70mΩ (=7mV) at first, decreasing roughly linearly with less than 10nm of noise, enabling thinning the foil down to under a micron before it broke.
If you were doing this electrolytically, you could presumably stop the etch directly from the microcontroller with a transistor or even directly from a GPIO.
Then he repeats the etching with a large sample in the same bath with the thin foil strip whose resistance he’s measuring. And then he corrugates his foil ribbon microphone ribbons before etching them to thin them, which answers a burning question I had, and then he recorded the video with the resulting microphone!
An amusing editing trick is that he recorded himself erasing a whiteboard drawing line by line with his finger, then played the video backwards with a voiceover to make it look like he’s drawing with his finger.
on 02026-08-11#video by #Bigclive from 02025-07-25 about RF-blocking Faraday-cage anti-5G fabric, made of copper, nickel, and polyester. I think this is the stuff that those kids from Yale were laser-cutting at Noisebridge. #materials
on 02026-08-07it probably takes weeks to form peracetic acid #materials at STP from 5% vinegar and 3% H₂O₂ without catalysts. It’s used for sterilizing food-contact surfaces such as brewery pasteurizers and cheese processing plants, but is dangerous in air at 0.17 ppm.
on 02026-08-06Stephen Hobley’s recipe for etching #PCBs for #electronics #hardware with 3% H₂O₂, 5%-acidity white vinegar from Meijer, and some salt; this might form peracetic acid #materials. #bootstrapping
on 02026-08-06solid-state #batteries and their #materials #toread
on 02026-07-30#Nighthawk #video about #electrolysis for, e.g., electrowinning metal #materials. First big science error is at 8'08": “Actually everything that dissolves in water splits into ions when it does so.” Nope. He claims to be making #DIY ion-selective membranes using Robert Rowow’s recipe, using off-the-shelf PVC cement and ion-exchange resin beads from water softeners, reinforced with fiberglass cloth, but I’m not clear how he validates them. He recommends using a hot glue gun to hold the membranes in place in his water buckets with EVA. He also turns carbon welding blankets into conductive carbon felt electrodes. He reports 250mA at 1.2 volts from his semipermeable-membrane plastic-bucket Fe⁺⁺/Fe⁺⁺⁺ flow battery with roughly A5-paper-sized carbon-fiber electrodes. Also he makes hydrogen sealed into the cathode compartment of a cell with one of these semipermeable membranes.
on 02026-06-03#Titanium #pricing is 48.50 renminbi per kilogram, which is almost US$7. #materials #finance
on 02026-06-01CAB is the plastic that makes screwdriver handles stink like vomit. “It has improved weathering resistance and lower moisture absorption compared to cellulose acetate.” #materials
on 02026-05-26#PDF mineral commodities summary for #nickel #materials says it averaged US$15/kg on the London Metals Exchange last year
on 02026-05-17#ebook of Cooley’s Cyclopaedia of Practical Receipts, Processes, and Collateral Information, fourth edition (MDCCCLXIV = 01864), printed in London, on the page about corrosive sublimate #materials.
on 02026-05-10Gallium oxide semiconductor #materials work at up to 500° and down to 2 K (-271°).
on 02026-04-28#PDF #paper on shellac #materials crosslinking, especially under ultraviolet ("photoageing")
on 02026-04-28Shellac #materials do crosslink over time, called “aging”.
on 02026-04-28#Kolbe #electrolysis can make ethane, sebacic acid, etc. #materials
on 02026-04-28#Scrap-Science video of the #Kolbe #electrolysis of slightly acidified sodium acetate #materials to ethane (diluted with carbon dioxide) via free methyl radicals in a U-tube, requiring a platinum anode to hinder oxygen generation
on 02026-04-27#video about Marshall’s ammonium persulfate as a dry oxidant for #flying. #materials
on 02026-04-27#PDF article in AMPTIAC Quarterly, Spring 02002, Volume 6, Number 1, about nanothermite #materials including Al/Teflon, Al/MoO₃, and Al/CuO, described as “metastable intermolecular composites” or “MICs”, citing work by Jan Puszynski at South Dakota School of Mines, Wayne Danen and Steve Son at LANL, etc. Also they managed to deposit Fe₂O₃ into the pores of an aluminum aerogel by converting an organic Fe(III) epoxide into the oxide hydrothermally (Gash, Tillotson, Satcher, Hrubesh, Simpson, 02001).
on 02026-04-22Play-Doh #MSDS #PDF says it’s 37% wheat flour, 5.7% NaCl, 5.7% CaCl2, 4.74% cornstarch, 2.9% mineral oil, 1.7318% TiO2, 1% mica, and, most amusingly, 0.1047% carbon black. Presumably the rest is water. Wikipedia says it contains borax but this MSDS doesn’t. #materials
on 02026-04-14#Thought-Emporium #video on #manufacturing hardened iron #materials by case-hardening with charcoal, nitriding with potassium nitrate and chloride, or cementation with charcoal followed by forge-welding it into pattern-welded steel. Attempts at plasma nitriding failed. Unfortunately the video contains a lot of filler stock footage.
on 02026-04-14#video on a newish unstable nitrogen allotrope (half-life 36ms at room temperature). #materials
on 02026-04-13#CodysLab #video on distilling isopropyl alcohol #materials with a countercurrent tube-in-tube heat exchanger built in a 20ℓ bucket on top of a mini-fridge, with a plastic tube on the outside of a copper tube. So he can distill at room temperature (and below) without needing a vacuum. He’s distilled about 250mℓ in a day with airflow driven by an aquarium bubbler.
on 02026-04-09The USSR farmed Kazakh dandelions in WWII for #rubber #materials, and Continental has been selling bicycle tires made from them since 02019. #history
on 02026-04-09#video on trying and failing to make #carborundum #materials in the shed in a zirconia crucible; the Australian YouTuber ran into trouble with #export-controls in #China being perhaps incorrectly applied to YSZ. So he used calcia-stabilized zirconia. But an induction furnace is the wrong tool.
on 02026-04-06using #aluminum #materials as a fuel by producing hydrogen from water with them. #PDF #paper
on 02026-04-06CalBlend detergent mix is still around. #materials
on 02026-03-15#lime burning can be pretty efficient if your kiln is a #regenerator, like 3.6MJ/kg of lime (contra a theoretical ideal of 3.15 MJ/kg of lime). #materials
on 02026-03-03“Geopolymer Chemistry and Composition: A Comprehensive Review of Synthesis, Reaction Mechanisms, and Material Properties—Oriented with Sustainable Construction” #geopolymers #cements #materials #paper #toread
on 02026-01-15ferric chloride stains on skin last a couple of days, but in clothing are permanent unless removed with oxalate. #materials #safety
on 02026-01-14someone got ferric chloride burns on their arm, people tell them to not worry about the burns but fix their technique. #materials #safety toxicology
on 02026-01-14#paper on a guy whose stomach they had to remove at the Hospital Posadas because he tried to commit #suicide by drinking 500 mℓ of ferric chloride solution, which caustically etched his mouth, stained his teeth brown, and produced metabolic acidosis. They treated his acute iron intoxication with chelation therapy. Finally he died in the hospital 8 days after the operation, “product of a systemic inflammatory response syndrome (SIRS) due to respiratory complications in intensive care unit.” #medicine #materials #safety #toxicology
on 02026-01-14another #video #toread about aluminum-foil #batteries by #Thoisoi, who turns out to be Polish or Estonian, not Russian. He uses stainless-steel window screens as the cathode current collector, because it’s an #aluminum-air battery; in one case he adds a layer of graphite conductive spray paint to the screen. Additionally he’s going to use activated carbon for the cathode, sprinkling it on the epoxy-coated graphite-coated fine stainless-steel mesh, then pressing it in a jugaad five-tonne hydraulic press at 100° for 40 minutes, though he says you could just leave it for 12 hours at room temperature. In the end he has eight cathodes, four with a coarser mesh; the dry cathodes measure as only 8Ω or so on a non-autoranging multimeter. He’s making pouch cells with a food-bag hot sealer, which melts sheets of polyethylene (LDPE) together with a hot wire. His anode is 8-layer-thick aluminum foil. As an electrode separator, he uses a wet paper towel, and sandwiches the anode between two cathodes, I suppose to keep air from getting to it. Weirdly, he seals the pouch cell in plastic, so I’m not sure how the air is going to get to the cathodes. One of the cells uses 20mℓ o an electrolyte made from 5g NaCl and 5g NaHCO₃ #materials in 100mℓ of water, giving 0.75V which rapidly declines. On injecting 10mℓ 10% NaOH into the bag with a syringe, it perks up to 1.6V. Short-circuit current is 750mA, but he needs two in series (measuring 2.60V on the multimeters) to dimly light a red LED, suggesting an “internal resistance” of hundreds of ohms. With the NaOH he thinks its shelf life is only a few hours; his batteries were dead in four hours of playing his CD player.
I thought he was going to explain the results he got from different cathode geometries, but he never does. Also he never reports the power output of the battery or explains how the air is supposed to get in.
on 02026-01-14#Engineering-Knits #video on #gardening your own flax #materials #toread
on 02026-01-03#video on copper #materials #safety mistakes accidentally producing N₂O in a runaway reaction. Also changing copper hydroxide’s color from green to blue by dropping the pH, and then converting it to blue vitriol in the obvious way.
on 02025-12-21The most common structural steel #materials are A36 steel, with the usual E = 200GPa for steels, a yield stress of 250MPa (or 220MPa for thick plates), and UTS of 400–550MPa. It’s up to 0.26% carbon, making it a mild steel, not a heat-treatable carbon steel.
on 02025-12-16Fluorine azide #humor #materials
on 02025-12-12Ian McKay on “Outside Takes on Clean Energy”, linking to articles outside #Orca, including one on how lower #energy #pricing could make #aluminum cheaper than #steel #materials
on 02025-12-12#materials #pricing and the prospects for decarbonization either via electricity or via biosynthesis, with a table of “idiot indices” for different metals (cost of of metal, divided by cost of ore plus energy at current prices) from #Orca
on 02025-12-12archive of https://www.technologyreview.com/2025/03/12/1113130/green-steel-boston-metal/ #news from March about #Boston-Metal and their electrolytic #steel making process. #materials
on 02025-12-12#video from March of tapping molten iron off of #Boston-Metal’s molten oxide electrolysis cell for making #steel. #materials
on 02025-12-12by Aravindh Rajan and Ian McKay at #Orca: #titanium #materials #pricing is 60× the cost of the ore (a cheap white pigment and filler for plastics) plus the change in enthalpy, a very high multiple, so this post explores where the extra cost comes from. Basically refining titanium is a five-step process, the first step being mining, and the cost doubles at each step. After three steps you have titanium sponge, which is hard to turn into the desired fully dense metal, which in turn is hard to machine, quadrupling the cost of final parts. Could you maybe just use the sponge, maybe as the filling/web in sandwich panels? Also ECM seems promising as a way to reduce the cost of the last step, machining. Lists past failed attempts to bring the cost down, including the FFC Cambridge process but also five more recent proposed cheaper processes. There’s an astonishing graph finding roughly 100× lower fatigue life for HIPped (hot isostatic pressed) titanium parts than for wrought parts. “Molten titanium will react with all metal oxides except yttria, zirconia, and calcium oxide. Due to calcium’s volatility at titanium’s melting point, titanium can also react with calcium oxide to form calcium vapor, if there is no excess of the latter.”
on 02025-12-12cadmium zinc telluride semiconductor #materials make more sensitive photon detectors for X-ray and PET scanning machines, as well as space telescopes, etc., but it’s cheaper than it used to be.
on 02025-12-12another #video of instant self-heating hot pot using, probably, quicklime #materials
on 02025-12-05#video of instant self-heating hot pot using quicklime #materials
on 02025-12-05#Cesar #video on mixing polystyrene #materials softened in gasoline with polyvinyl acetate wood glue in order to get a smoothly spreadable waterproofing coating. Surprisingly, the PVA glue mixes homogeneously with the softened polystyrene. Jorge Donadelli, another biochemist from La Plata, suspects that the PVA is emulsifying the mixture. But the demo of waterproofing doesn’t seem very promising actually.
on 02025-11-22#Steve-Mould #video on #supercritical CO₂ #materials
on 02025-11-21rubber #materials for long-term Mars exploration #PDF
on 02025-11-20Birgitte Stofferson’s #dissertation about safe containment of NaOH #materials, for example in inconel, which erodes 1.06mm/year in 600° NaOH.
on 02025-11-20Dacite is a low-alkali felsic extrusive igneous rock. #geology #materials
on 02025-11-20Oh, 1% CN tear gas (chloroacetophenone) is what’s in old Mace. So I guess I have been tear-gassed, but not with CS gas. #materials
on 02025-11-17#video on #casting bronze with sand cores made from sand and 5 wt% #waterglass #materials rather than, as in his previous video, molasses and flour. He got his waterglass from a pottery supply store and gas-cured it in a ziploc. He’s using hose clamps on a split pipe for his mold for the core. With 5% he can still break it by hand after curing.
on 02025-11-14#video on #DIY refractory glue #materials consisting of waterglass and garden lime, which ought to fire to something like wollastonite. He tests it with a DIY oxyhydrogen torch.
on 02025-11-11#video comparing #DIY refractory firebrick #materials made with vermiculite and perlite, but not giving much detail
on 02025-11-11#video on #DIY refractory firebrick #materials recipes but not giving much specific information
on 02025-11-11#video from #Misadventures-with-materials with a recipe for high-temperature calcium phosphate refractory #materials: triple superphosphate in the coffee grinder, slaked lime, and perlite (run through a food processor), 3.7 parts triple superphosphate (Ca(H₂PO₄)₂) to 1 part lime, mixed as powders, then mixed as equal volumes with the perlite, then pressed dry into a mold, then moistened under pressure, to keep bubbles from expanding from the heat and cracking the material apart. It expands when curing, so it’s better to have a mold you can take the sides off of. #cements #toread
on 02025-11-11more #video about #cements #materials which falls pretty far short of including enough information for reproducibility, talking about “bast” fiber without specifying what plant, confusing caliche with clay, misstatements (“portland has clay in it”, “those [lime and portland bound concretes] need oxygen to cure”), etc. He’s also very confused about #geopolymers. I’m amazed how many factual errors he was able to fit into a single 21-minute video. Where it’s not wrong, it’s super unclear. Also I thought this was going to be about MgO cements, because that’s what it says in the title, but he doesn’t say anything specific about MgO, except that I think he’s confusing it with Al₂O₃. #Plonk to "mrglasecki".
on 02025-11-11#video #toread by #Murray-Smith on magnesium-oxide #cements, specifically Sorel oxychloride cement #materials
on 02025-11-11magnesium phosphate #cements #materials #toread
on 02025-11-11#video on building a shower with a magnesium-phosphate drain, using magnesium oxide, Mega Buds potassium phosphate fertilizer, and borax, used to stiffen burlap. #cements #materials
on 02025-11-1135' #video on magnesium phosphate #cements #materials for airfield pavements for enhanced corrosion resistance and heat resistance by a guy whose product has been in service at Cannon Air Force Base for three years now. Apparently leaked lubricants were somehow forming phosphoric acid in the jet wash, which ate the concrete. Magnesium-phosphate pothole fillers were immune. Magnesium oxide (light, hard, or dead burned), ammonium or potassium phosphate salts, fly ash (40–60%) and boric acid to retard the reaction (though boric acid degrades the strength, by about 25% at 3% boric acid), and water. The set cement is struvite-K (MgKPO₄). He mentions that any unreacted phosphates are highly soluble, making porous concrete after they leach out. See ERDC Technical Report 20-12 from 02020 by Ramsey, Scott, Weiss, and Tingle. #toread
on 02025-11-11#CC #paper “Thermal Stability and Eutectic Point of Chloride-Based High-Temperature Molten Salt Energy Systems” on #materials
on 02025-11-11a review #paper from 02022 of thermal #TCES #energy-storage #materials #toread
on 02025-11-11#video #toread on dysprosium #materials
on 02025-10-21#NFTI #video #toread about #manufacturing camping teardrop foamie trailers out of XPS #foam #materials
on 02025-10-21#video on #materials with “dilatency” such as sand, where compressive stress increases their volume
on 02025-10-20apparently "Plasti Dip" is a goo you can dip metal parts in to quickly add a non-slip rubberized coating, “usually used in adding grip to hand tools”. I guess it’s like dissolved in some kind of solvent that evaporates? #manufacturing #materials #video
on 02025-10-18#video #toread about Laura Messing and bio #materials in #Argentina
on 02025-10-18#video #toread of #faircompanies looking at bioplastic #materials at Barcelona’s Fabricademy, interviewing Anastasia Pistofidou, lead Material and Textiles researcher at Fab Lab Barcelona and co-founder and Scientific Coordinator of the global Fabricademy educational program.
on 02025-10-18#manufacturing fake leather #materials from orange peel #video (Susana Jurado, Elisenda Jaquemot, Nuria Bonet) from 20g wool, 5 ℓ water, 135g sodium alginate, 421 g (?!) glycerin, 56g coconut oil, an undisclosed quantity of calcium chloride, and I guess orange peel as a filler, but only 120g of it (maybe that’s the dry weight because it looks like it’s about 2–4 oranges, and they do run it through a dehydrator before grinding it to sawdust and sifting). The wool is added in hunks after 24 hours, and then the calcium chloride is sprayed on the top and bottom before drying 3–7 days. Fab Lab Barcelona, part of the SISCODE project.
on 02025-10-18#video #toread on “frying” food in a couple of kilos of hot salt (180°) in a wok after preheating for 8 minutes. Specifically chicharrones and palomitas. Suggests you can use the palomitas to measure the 180°. He also puffs some rice by presoaking it for 3–4 hours in water before mixing it into the salt. #cooking #materials
on 02025-10-18#Giestas #video on #manufacturing cork-filled-agar-soled sandals using a corrugated-sole mold made from corrugated cardboard. The cork came from diced wine corks ground in a coffee grinder and sifted with a kitchen sifter to separate into cut, coarse, medium, and fine grades. 3 parts glycerin plasticizes 4 parts agar. A tiny amount of charcoal, ground in a mortar, is an additional filler for color. #Casting the heavily filled gloop in the cardboard mold looks fiddly. Used-tea-leaf tannin colors the alginate “leather” straps: 1 part alginate, 2 parts glycerin, 30 parts brown water, apparently by volume. The leather is crosslinked with a spray of 1 part CaCl₂ in 10 parts water. A box cutter tracing a masking-tape strap model tested over a sock cuts out the straps, which fit between the bottom sole and a lighter “midsole” made with 3 parts agar to 2 parts glycerin filled with coarser cork. Then the upper sole (insole) is softer, 1 part agar to 1 part glycerin filled with fine cork pigmented with mortar-ground tea leaves. Baked 1 hour at 100° with the fan on. #materials
on 02025-10-18#Giestas #video on #manufacturing an egg-shell-filled bioplastic bowl: 100mℓ water, 10mℓ glycerin, 15g agar, 2 drops clove oil, 100g eggshell (membrane removed, soapy-water-cleaned, oven sterilized, ground with mortar and pestle). So I guess the product is about 80% eggshell. He uses two glass bowls as the mold for #casting the thicker bowl. #materials
on 02025-10-18#video by #Giestas on #manufacturing a cup from used coffee grounds by binding them with agar and honey, melted in a double boiler before stirring in the grounds, then pressing the soft mass into a three-part mold made with #3D-printing, about 1cm thick. It suffers cracking damage from wetting/drying cycles. Oil of wintergreen to prevent mold, and he makes a planting pot. Relative quantities of honey, agar, oil of wintergreen, and coffee grounds are not disclosed. #materials
on 02025-10-18#video of #casting plaster of Paris and polyurethane in a high-density remeltable gelatin mold (50g water, 40g gelatin, 40g glycerin, but stronger if gelatin goes to 90g, maybe also with 2tbsp powdered sugar) without even a mold release. Alcohol spray to pop bubbles at the surface. #materials
on 02025-10-18#Nighthawk #video #toread about bioplastics #materials from potato or cassava starch, and spectrally selective cooling materials. 5 mℓ of honey can plasticize 30 mℓ of gelatin dissolved in 560mℓ of water and then dried in a food dehydrator in a silicone mold. Recommends a YT channel about bioplastics, @Giestas, a high-school teacher in Lisbon. Second recipe: 12 parts water, 3 parts cassava (or other) starch, 1 part vinegar, 1 part glycerin (as a plasticizer), optionally reinforced with cotton gauze. He claims you can separate potato starch by simple decantation. As usual, he butchers the science, claiming that freeze-dried starch gel is an aerogel. He claims that these starch gel films have high infrared emissivity, even though they look transparent to visible light. Third recipe, alginate — which, astoundingly, he mentions can be de-gelled by chelating the calcium with sodium citrate! And a suspension of calcium carbonate in sodium alginate can be gelled with vinegar, because that solubilizes the calcium! Or by using glucono-delta-lactone, tofu coagulant, to release acid over 10' to 20': 100mℓ water, 10g (sodium?) alginate, 2g CaCO₃, 2g GDL. Fourth recipe, agar, which dries into crystal-clear films that can resist water for a few days. 20g agar (!!) in only 100mℓ of hot water, 2mℓ dish detergent, whip with blender. #Giestas offers: “3 tbps agar, 2.5g citric acid, 3tbsp gli[cerin?], 1tsp baking soda” to produce foam; and “60mℓ agar, 30mℓ MGL [or “mel”: honey?], 60mℓ gli[cerin?], 180mℓ water, 5mℓ deter[gent?]”.
on 02025-10-17#history of #materials: celluloid’s origin as an ivory substitute for billiard balls
on 02025-10-15#clickbait #video about upcycling (#recycling) paper into plastic-like waterproof (no! “water resistant”) #materials. The recipe is water, cornstarch (gelatinized with heat), vinegar as a preservative, coconut oil as a plasticizer, and white laser-printer bond paper, onto which the sauce is brushed with a paintbrush and then allowed to dry. For an inkjet printer, obviously that mix would make the ink bloom, so as a “great little hack”, she recommends spraying it with an unspecified sealant first (she just says “polycrylic”, which isn’t a thing). To "antique" it she suggests mixing some instant coffee into the sauce. To fix the paper curling she recommends ironing the paper in a folded silicone mat afterwards. I'm not persuaded that this is superior to silicone thinned with paint thinner.
on 02025-09-29#video by #Malawey on #manufacturing with #8020 and similar aluminum T-nut extrusions. He prefers the Automation Direct brand. 30×30mm has pricing of US$15/meter (M6 fasteners ideal, or M8 for the end holes, 9mm groove depth), 20×20 US$8/m (M5 fasteners ideal, or M6 for the end holes, 7mm groove depth), 35mm DIN rail US$5.20. He cuts them with wood-cutting blades on wood saws, although his "wood blade" looks like it has a brazed-on insert on each tooth, presumably tungsten carbide, and it appears to say “CARBIDE TEETH / DIENTES DE CARBURO / DENTS DE CARBURE”, so it could probably cut concrete. He recommends putting some wax on the blade to make a cleaner cut, by cutting a bar of wax together with the aluminum. He reports that it is also possible to get a clean cut on cut magnesium #materials with a saw this way. He warns that “V-groove” extrusions are needed for rolling V-groove wheels on. Sometimes your screws contact the bottoms of the grooves because they’re too long, which can be remedied with a thick washer. For wheels he recommends #3D-printing a bracket to hold a rollerblade wheel. He spends several minutes demonstrting how to use SolidWorks to design such things by pretending they’re weldments.
on 02025-09-29#video #toread about making #DIY molds from flour and silicone #materials #toread
on 02025-09-28#video by #Makers-Muse about #3D-printing floppy elastomer filament #materials that aren’t TPU, like PEBA, polyether block amide (?) which apparently you have to print at about 250° to get good layer adhesion. Also, foaming TPU, glass-filled polybutylene terephthalate (PBT-GF), and regular polypropylene, for which you need to coat your bed with polypropylene packing tape or something to get it to stick. Also a TPU/nylon mix and PVA as a water-soluble elastomer. #manufacturing
on 02025-09-28#video #toread on #DIY #manufacturing rubrene, which is apparently a red- or yellow-fluorescent polycyclic aromatic hydrocarbon (5,6,11,12-tetraphenylnaphthacene), which apparently took him two years. Also it’s used as an organic semiconductor in OLED displays. #materials
on 02025-09-27#video showing a polyethylene plant operated by BP, starting from #ethylene (usually derived from cracking naphtha #materials) at 1500 atmospheres and 160° with about 20% yield of polyethylene on each go-around, so the unreacted ethylene gets compressed again.
on 02025-09-26#video of stock footage and animations explaining how #ethylene is industrially produced by thermal cracking of ethane #materials distilled from natural gas at 850° (catalysts unspecified), and the ethylene is reacted with butylene (using other unspecified catalysts) to polymerize it. Free-radical peroxide initiation is not mentioned.
on 02025-09-26#video #toread by Zack Freedman about FDM #3D-printing weird filament #materials like sinterable zirconia
on 02025-09-25#Veritasium #video about rubber #materials and their #history, and the risk of the South American Leaf Blight
on 02025-09-2516' #video #toread by #CodysLab on #mining magnetite #materials (on the beach with a shovel?)
on 02025-09-06The obsolete Brin process used barium oxide to separate oxygen from air, but fractional distillation of liquefied air and electrolysis of water became cheaper. The process used pressure-swing absorption and desorption of oxygen from air above 800° after removing CO₂ from the air with lye. #materials #history
on 02025-09-02#Polyimide #materials like Kapton as high-temperature capacitor dielectrics. #electronics #hardware
on 02025-09-02#video #toread of shooting sodium #materials at a watermelon
on 02025-08-31#Quartz #materials in various granulometries and purities.
on 02025-08-23interesting, only a group 2a “probable carcinogen” despite being a chloroalkane. Great solvent for rosin. #materials
on 02025-08-12how #teflon #materials self-extinguish when you remove the flame source
on 02025-08-10the first alloy steel. #metallurgy #materials #history
on 02025-08-10German 3M page about cyanoacrylate #adhesives #materials. “Cyanacrylat-Klebstoffbasis”.
on 02025-08-05Jean Harlow’s platinum blonde hair may have killed her. Fails to mention bluing! #materials #history
on 02025-06-20#video reporting on experiments heating widely-available Robax glass-ceramic #materials to 994° for 10' to reduce their CTE from -0.6ppm/° to -0.058ppm/°, or much lower in the range 20°–25°, better than Schott Class 2 Zerodur, but much worse than Class 0 Extreme Zerodur. Ceran, a different glass-ceramic, is nearly as good when similarly converted at 961°.
on 02025-06-17#video by #Hyperspace-Pirate on #bootstrapping ozone #materials with corona discharge instead of brown nitrogen dioxide with thermal plasma arcs. A Leyden-jar sort of arrangement with water on the inside and a mesh on the outside seemed to work well, and then he switched to just using test tubes filled with water to keep arcs from burning through the glass. But what he really wanted were nitrates, and the Birkeland–Eyde process is 40 times more efficient. “So, anyway, that’s the fun world of ozone. It smells terrible and I hate it. Bye.”
on 02025-06-17page giving #energy-density of different kinds of #lithium-ion #batteries #materials.
on 02025-06-17The International Firestop Council: #video on intumescent firestop #materials. #safety
on 02025-06-17induction hardened chrome plated steel shafting with 110ksi yield stress and 50 Rockwell C hardness. #materials
on 02025-06-17#Nighthawk #video on waterproofing and stiffening #cardboard by brushing on 500mℓ isopropanol, 125g shellac, 15g beeswax (emulsified), 2g metal stearate (slowly stirred on low heat on an electric burner outdoors). Also demonstrates a totally game changing edge-sealing technique where you cut halfway through the cardboard to isolate one side, then fold it over. Also you can stiffen the surface with wheat paste. And maybe pasting on extra layers of newspaper or paper bags. Also, you can edge-splice panels with the same cut-halfway-through technique and then pasting the sides thus isolated. He also touts his waterproofing mix as a way to make fabric waterproof, showing some very impressive demo video. His second waterproofing recipe is 100g EVA hot glue diluted with 25g paraffin wax and 20mℓ mineral oil. He also demonstrates homemade lampblack with a vegetable oil candle under an aluminum tray for UV protection, but thinks calcium stearate might work well enough for UV protection, which is his reason for including it; he recommends reacting soluble sodium stearate (made from stearic acid and lye) in water with sulfate of aluminum, zinc, or magnesium, or muriate of lime, to form the insoluble metal stearate. Doesn’t contain his usual total mangling of the science. #DIY #bootstrapping #materials
on 02025-06-14copper–lead–tin phase diagrams. #materials #paper
on 02025-06-05elemental-abundance-charting version of the periodic table #materials
on 02025-05-20#NileRed #Youtube video replicating the "bulletproof wood" #materials paper. He had to keep checking the pH when rinsing the wood to find out when he’d removed all the lye, which took 7 (one-hour?) washings. The result was not bulletproof at all the first time around, not stopping even a pellet. Later iterations improved somewhat but still yielded to .22 LR, though with two layers glued together and rotated 90°, the bullet was stopped. Three layers didn’t even splinter on the back side and was able to stop a 9mm bullet.
on 02025-05-20discussion of InventWood #Superwood #materials which are 11× as strong as regular wood, twice as strong as ASTM A36, and only 1.3g/cc. Procedure from the paper by Song et al. (Liangbing Hu) in 02018 is to boil it with 2.5M lye and 0.4M sodium sulfite for 7 hours before densifying it with 5MPa for “about a day”, removing optimally 45% of the lignin to permit better compacting. No additional binder. The #bulletproof-wood paper. However, the company’s website is full of fraudulent images.
on 02025-05-20MgS melts at 2000°, has ΔH of -347kJ/mol (compared to MgO’s -601.6), and decomposes in water. #materials
on 02025-05-20Minium (Pb₃O₄) was used as a red pigment in paints, according to this page from “The Chemistry of Paints and Painting”, sometimes called “saturnine red”. #materials
on 02025-05-08#video on #Nighthawk trying to form stable colloid #phase-change #energy-storage #materials with sodium lignosulfonate #toread
on 02025-03-26#video by #Thoisoi on making metal foam #materials. Very low quality text-to-speech audio (in particular, missing all the quantitative information!) and a significant amount of talking-head filler and stock-footage filler, and he spends a bunch of time talking about misleading relationships between metals’ density and chemical properties. He finally starts making hydrogen-blown aluminum foam at 10'20" after some fake video of typing a Google search by melting calcium into it at supposedly 760° in his furnace, but the crucible and alloy don’t glow, so that must be the wrong temperature. Some footage of reacting calcium granules with water and setting them afire. He adds titanium hydride as a hydrogen source, mixing it into the alloy with a quartz tube as it’s starting to decompose, so that the hydrogen will dissolve in the aluminum.
But that didn’t work, so he tried again without adding any calcium beforehand, then adds the calcium granules once the aluminum was already melted; this time, when he adds the hydride, the aluminum starts to foam immediately, but only foams a little.
On a third trial, he lowered the furnace temperature to 700° (but the aluminum and crucible are still not glowing) and got slightly better foam, but still pretty bad, more like sourdough bread than a sponge.
I suspect the calcium is to reduce the surface tension of the aluminum, because the alloy wets the crucible more, but it doesn’t seem to have worked very well.
He bought some commercial aluminum foam samples, which weighed 0.27g/cc, but didn’t bother to test its material properties quantitatively.
on 02025-03-25#video on glass-ceramic #materials like Robax and Zerodur for #bootstrapping optical instruments from household materials, measuring their CTE with a homemade length measuring rig and an infrared thermometer. Also mentions “Photoform” photolithographable glass. He explains how lithium (and zinc) silicoaluminates have a negative CTE and thus convey a vanishing CTE on the glass-ceramic composite, and how 1-6% of titania or zirconia is included as a nucleation agent. He recommends Bach (ed.)’s book Low Thermal Expansion Glass Ceramics.
on 02025-03-25#Primitive-Technology #video on a smelt (#bootstrapping #materials) with a flywheel-driven blower, giving disappointing results.
on 02025-02-06#cooking pretzels with sodium carbonate #materials made by boiling baking soda, compensating for the lack of lye by brushing on some egg
on 02024-12-13apparently aluminum rectifiers using borax #electrolysis make a faint glow. #electronics #materials
on 02024-12-13discussion of how apparently aluminum rectifiers using borax #electrolysis make a faint glow. #electronics #materials
on 02024-12-13Fragments of the Muonionalusta meteorite are prone to rusting in moist air. #meteorites #materials
on 02024-12-12Iron Meteorite Widmanstatten Pattern Produced in Laboratory #meteorites #materials #PDF #paper
on 02024-12-12#PDF WIPO #patent application WO 2016/173248 A1 on #flash-iron-making with water gas. Chinese but not Zhang Wenhai’s team. #materials
on 02024-12-11#PDF brochure on #flash-iron-making #materials
on 02024-12-11#China researcher Zhang Wenhai is reducing finely powdered iron ore by injecting it into a superheated furnace where it reduces in 3–6 seconds instead of hours. “Zhang Wenhai's team has successfully addressed this challenge by developing a vortex lance capable of injecting a substantial 450 tonnes of iron ore particles per hour. A reactor equipped with three such lances can produce a substantial 7.11 million tonnes of iron annually. Importantly, this innovative lance technology has already entered commercial production.” More information in “The #flash-iron-making process, detailed in a recent research publication in the journal Nonferrous Metals” and “a patent in 2013”. #materials
on 02024-12-10#video on colloidal crystal #materials (#metamaterials like opal), just an #interview with Sharon Glotzer of UMich
on 02024-12-04“Mechanically strong yet metabolizable supramolecular plastics by desalting upon phase separation” #PDF #paper #materials “A strong, glassy supramolecular polymer has been shown to prevent the formation of marine microplastics by slowly dissolving in salt water into metabolizable compounds. Cheng et al. show that salt bridging between sodium hexametaphosphate or sulfated polysaccharides and guanidinium sulfates expels sodium sulfate to create a cross-linked network that is stable until the electrolytes are added back. The dried material is a moldable and recyclable thermoplastic that can be water stabilized with hydrophobic coatings.”
on 02024-11-22#video #toread on #manufacturing a kilogram of potassium #materials
on 02024-11-14#video on #bootstrapping acetylene #materials via calcium carbide from seashells and driftwood in an arc furnace made by winding 50 turns of 8-gauge wire through the hole of a large toroidal transformer from a 110VAC→240VAC converter. The wire turned out to be too thin, so he rewound it with 25 turns of 6-gauge. He kept melting his improvised furnace made from firebrick, so he switched to using a stainless-steel cup and a “skull crucible”. #scouting
on 02024-11-14#video about #bootstrapping salt #materials by oxidizing urea (from #CodysLab urine) with bacteria on a charcoal packed bed supported on hardware cloth with a process tower made of a Rubbermaid trashcan and a 200ℓ drum, with water sprayed through plastic pipes connected via tee hose barbs, mounted with baling wire, using a powerline timer to run the pump a couple of hours a day. An aquarium bubbler keeps the reservoir aerated; an aluminized tarp keeps sunlight off to prevent algae. I thought this might emit a lot of ammonia, but he said, “I knew I had fed it too much when it started to smell like a truck stop bathroom,” but normally it smells like a “well-cycled fishtank”. Calcium carbonate chips in the reservoir keep the pH from dropping too low for the bacteria. He thinks he would need a machine three times bigger to process all his urine.
on 02024-10-30#video about glow powder strontium aluminate #materials fired in a microwave kiln. #toread
on 02024-10-30#video about #bootstrapping pure #materials from fertilizers. Like calcium nitrate from the hydrated double salt with ammonia. (Boiling with slaked lime drives out the ammonia as gas.) Urea he simply recrystallizes with water. Ammonium sulfate he recrystallizes with water by evaporation, which is tedious because you can’t crystallize it by cooling. By #Apoptosis. #scouting
on 02024-10-30#video on #bootstrapping H₂SO₄ from epsom salt with a PbO₂ electrode and a clay pot #materials #scouting
on 02024-10-23#video on #3D-printing an #STM for #microscopy. This is a unimorph disc type made from a piezo buzzer; he ruined several before switching to ultra-fine magnet wires and low-temperature solder (ChipQuik?). His kinematic mount seems to consist of three bearing balls, one in a V-groove, one on a flat glass surface, and one in some kind of a pit, each adjustable with a knurled screw. He seems to have used heat-set inserts to build his frame out of 3-D printed plastic — although PLA has the best TCE of common plastics, he’s using PA-CF, carbon fiber reinforced nylon, which ought to be pretty stable in the X and Y dimensions, like wood. (He mentions that many STMs are made out of Zerodur or similar glass-ceramic #materials.) Printed on a Bambu Lab X1 Carbon. The voiceover might be an AI reading a script because it mispronounces a lot of words and sometimes gets the prosody of sentences wrong, despite having a bog-standard GA accent. He put metal tape on the parts for EMI shielding; looks like aluminum flashing. To pre-amplify the nanoamps or picoamps signal from the tunneling current, he copied Dan Berard’s open-source STM preamp circuit, naturally using a current-to-voltage converter built around an op-amp, but I can’t tell which one. He shielded his cable to the probe and put the analog electronics in a Faraday cage to reduce EMI further, getting only about 10pA of noise. Berard’s #electronics design used an OPA124, but he says “The chips used in Dan’s design are hard to find these days.” When it comes to #microcontrollers #hardware, he’s using a Teensy 4.1. He’s using an aluminum plate and some rare-earth magnets to damp the oscillations of his stable platform. “This is the first atomic image captured by a 3-D printed scanning tunneling microscope.”
on 02024-09-28#video #toread on #manufacturing a "murrine" vase at First City Art Center. I thought this was going to be about calcium fluoride #materials, but actually it’s just sections diamond-sawn from glass canes. The end result unfortunately looks kind of badly drawn. #glassblowing
on 02024-09-16The Corralón de Marco in San Martín at the edge of Capital Federal sells baling wire for construction, “hierro dulce para la construcción 6 mm, marca Acindar”, for AR$3700, presumably per kilogram. #materials #pricing #wire
on 02024-09-145/16" copper brake line (caño de cobre para freno) for 14 meters for AR$79500 (US$64, US$4.50/m) #materials #pricing #pipe
on 02024-09-14RF Repuestos Accesorios in Rosario sells 2mm copper “tubo capilar” for “refrigeracion” for AR$16163 per meter (US$12.93). #materials #pricing #pipe
on 02024-09-14Oddly enough, Alumina Argentina SRL in Caseros sells 12.7mm round brass tubing, 0.5mm thickness (or possibly 1mm), at only AR$13770 per meter (US$11). #materials #pricing #pipe
on 02024-09-14Alumina Argentina SRL in Caseros sells 3.17mm round brass tubing, 0.5mm thickness, at AR$31503.95 per meter (US$25). #materials #pricing #pipe
on 02024-09-14soda-ash #materials in the world market and their importance for lithium extraction
on 02024-09-09#video on #manufacturing SO₃ #materials #bootstrapping by #NurdRage. I didn’t know you could dehydrate H₂SO₄ with H₄P₂O₇! But he’s dehydrating it with Na₂S₂O₇ instead.
on 02024-09-04another #video on #manufacturing #ethylene #materials automatically by #Hyperspace-Pirate. He wants to use it as a second-stage refrigerant for his vapor-compression cryocooler for #cryogenics. He wants to separate ethanol into ethylene and water over a propane-heated sapphire catalyst (Wisesorb activated alumina from wisesorbent.com in 3.5mm balls) at 450°, which is fucking awesome. Around 300° to 350° you would instead get ether, and above 550° you mostly get carbon and hydrogen, the production of which starts at around 500°. Between 400° and 500° you mostly get ethylene (and water). Aluminum pipe contains the catalyst (and a thermocouple for temperature control), and copper line and flare nuts move the ethanol and ethylene vapor around. The pieces are supported on cinder blocks and bricks on what looks like a concrete floor. Bubbling the output through water produces a lot of flammable gas, which is probably ethylene. He adds a plastic juice bottle full of water as a bubbler to remove particles and a second plastic juice bottle full of silica-gel desiccant to separate the ethylene from the water, and then a dust filter to remove particles of the silica gel. He bolts together some aluminum L-profiles to hold things in place and 3-D prints a fixture for the bottles. A “25-foot” condenser coil of copper line with a fan blowing on it serves as a heat exchanger to cool the hot ethylene to near ambient. A second bubbler collects the liquids, which include a significant amount of ether. He collects the ethylene output in a beach ball. He uses a fridge compressor to pump it from the beach ball into a pressure tank previously purged with propane. His 500cc of 151-proof Everclear turned into 69.7g of ethylene, only a 39% yield, probably because he made about 50 grams of ether. On a second run he used a higher catalyst temperature and got a 70% yield. Chemical engineer in the comments: “It absolutely blew my mind to see someone casually building a packed-bed plug-flow reactor from plumbing parts and unspecified alumina beads in his garage, and the damn thing actually working! Seriously, well done! (Deep down I’m almost insulted by the fact you managed to get a decent yield without doing any equations to work out the reaction rate, and therefore flow rate and reactor length required 😂)” but he also suggests that the output ethylene product is probably contaminated with a lot of ether.
on 02024-09-03#video #toread on #manufacturing #ethylene #materials automatically by #Hyperspace-Pirate
on 02024-09-03#video on lithium hydride reducing agent #materials #toread
on 02024-09-03#NileRed #video about metal glass #materials, specifically Vitreloy 1, an alloy of zirconium (41.2 mol%), beryllium (“the asbestos of metals”, 22.5%), titanium (13.8%), copper (12.5%), and nickel (10%). Shows how to make a lab-scale arc melter from a common arc welding power supply! Tungsten electrode, water-cooled copper crucible, argon-filled glass chamber. But he ended up buying one on AliBaba instead; the final price was US$14440, including US$1570 of freight. Vitreloy 1 vitrifies when cooling even as slowly as 1°/s, so the water-cooled copper crucible was enough. Really astonishing viscous glassy goo behavior at 36'43", like sugar syrup instead of any metal I’ve ever seen. (It also shatters like glass when he cuts it with bolt cutters). He found suction casting of the Vitreloy to be very difficult, as on his first four attempts the metal didn’t fill the mold at all. On his fifth attempt, with 30% more metal, he successfully cast a metal disc, and similarly on attempts 6, 7, and 8. But then it wasn’t insanely bouncy like he expected, a problem he was able to fix with superglue. Video has a comment by “jaskaran_singh_saini” saying, “The metallic glasses I invented have been the most recent major advancement in this area. (...) The thing Nile mentioned about the metallic glass not being safe to grind and polish because of beryllium is not true. Once the beryllium has been absorbed into the metal matrix, it is very safe. I literally produced thousands of these metallic glasses in my lab during my PhD, and some in very big sizes and they are all safe.”
on 02024-09-02#video #toread about #manufacturing TeO₂ glass #materials with bright fluorescence
on 02024-08-31#video of #bootstrapping dichromate #materials from stainless? He starts by dissolving 18/0 stainless steel forks in 98% H₂SO₄. To 789g of forks and 250g H₂SO₄ he added water. He got hydrogen bubbles and a green solution and the plastic tub started melting from the heat, so he added distilled-water ice. He used 920g sulfuric acid total. After three days much of the forks had dissolved. After a week much of the forks were dissolved and he lost patience. He tried to separate the iron sulfate from the chromium sulfate with a water recrystallization and got a lot of it out. He had 127 grams of forks left, so 662 grams dissolved. A third vacuum filtration removed most of the carbon powder. 1.5kg of sodium carbonate, a large excess, converted the chromium sulfate into hydroxide and the residual iron sulfate into iron (II) carbonate. He said a lot of the iron (II) sulfate had oxidized to iron (III), but I’m not sure if this was caused by the alkalization. The sludge settled somewhat during the night, so he siphoned off some sodium sulfate supernatant, starting the siphon with a syringe. Gravity filtration through cotton balls in plastic water bottles over two weeks concentrated the sludge somewhat, draining his soul. Then he oxidized it from Cr(III) to Cr(VI) with 760g of calcium hypochlorite. Vacuum filtration for four hours was able to separate the precipitated iron hydroxide, leaving a urine-like calcium [mono]chromate solution, which he boiled down for another week, periodically filtering out the precipitated chromate crystals. For disposal, he reduced the contaminated waste chromate with sodium sulfite in a hydrochloric acid catalyst. A reaction with more H₂SO₄ converted his yield of 62.5g of calcium chromate dihydrate to dichromate, precipitating out all the calcium as sulfate. To finally switch it to K₂Cr₂O₇ he added potassium carbonate, expecting a CaCO₃ precipitate, but what he actually had was dichromic acid at that point. He neutralized it with KOH and boiled it down further and did more vacuum filtrations to crystallize 40g of K₂Cr₂O₇, a 12% yield.
on 02024-08-28#video #toread of #bootstrapping #manufacturing potassium permanganate from 40g MnO₂, 55g KOH, 30g KNO₃, 5.5% NaOCl, and 31% HCl #materials #scouting
on 02024-08-27#video of #NurdRage making chloroplatinic acid #materials #bootstrapping #scouting
on 02024-08-27#video by Mikkel deMib on pit-firing #ceramics #materials with glaze, which he says is “theoretically impossible” I guess because you’ll lose the pit-firing colors. He’s going to try on a porcelain vase he previously glazed the inside of at 1260°, which he says will guarantee that it’s waterproof anyway. Also his idea of “pit firing” seems to involve a steel drum; I think he's just calling it “pit firing” because he’s using wood, even though no pit is involved anywhere. He colors his once-fired white porcelain with ferric chloride, and cobalt sulfate, and some rotten banana peels, and copper carbonate, and salt, and steel wool, and newspaper, and coffee grounds, and eggshells, all wrapped up in “tinfoil”, probably aluminum foil, because he probably doesn’t know the difference between aluminum and tin. To stick the “tinfoil” to the ceramic he uses hairspray or spray glue. Some of the “tinfoil” survived until the end of the “pit firing”. It all kind of looks horrible; he keeps saying it looks “much more interesting” but to me it looks like mold grew all over it.
on 02024-08-26You can cross-link #chitosan #materials with acetaldehyde. #CC BY
on 02024-07-28#video on #manufacturing borosilicate glass #materials in a microwave. His glass ate his insulating firebrick, but he was able to get it to work by using a ceramic crucible as a firebrick liner.
on 02024-07-10#PDF of #PolyCast filament datasheet for #3D-printing casting molds. Doesn’t say what’s in it. 1.1g/cc, absorbs 2.09% water at 70% RH at 23° with a time constant of about a day, glass transition of 70°, decomposes at 260°, heat deflection at 52.7°–66.5°, 1745MPa±151MPa Young’s modulus, 35.7MPa tensile strength, 5.8% elongation at break, prints at 190°–220°. I wonder if you could anneal it like PLA. Supposedly it’s made of PVB, whatever that is. #materials
on 02024-07-10#video about #bootstrapping silicone #materials from 40mℓ of sodium silicate (modulus and concentration unspecified but it looks syrupy) and 10mℓ of 95% ethanol, which he claims ethylates the silicate chains. Then he squeezes the water out of it. The resulting silicone is super bouncy, much more rigid than polydimethylsiloxane. Very impressive. By #Apoptosis.
on 02024-07-10pointer to the ACS #ferrates symposium series book. #materials
on 02024-07-10#Thunderf00t #video attacking "TwobitDaVinci" but mostly describing how evaporation of water #materials works
on 02024-07-07#CodysLab #video #manufacturing a cast-iron skillet with thermite #materials
on 02024-07-07human-interest #documentary #video by Björn Platz on energetics in old-highrise demolition, mining, #materials science, film special effects, airbags, etc., including the history with Ascanio Sobrero. Significant factual errors, including Sobrero’s first name, the health effects of nitrate, and the physical state of liners turned into jets. Shows the use of burning pollen in film special effects, which is totally hilarious, and the use of 3-D modeling software in granite quarrying, and nanodiamonds and nanosupercrystals (of carborundum?).
on 02024-07-06old #video #documentary on #Nitinol #materials showing heat engine #mechanisms at the Lawrence Berkeley Laboratory, by Ridgeway Banks, assisted by Professor McMillan. The video credits Stewart Brand for first drawing attention to it in CoEvolution Quarterly. Looks like about 01975. They were hoping they could convert waste heat into a solution to the energy crisis.
on 02024-07-06time-wasting talking-head and stock-footage #video on #graphene #materials, using tennis courts as its standard measure of area, with the occasional second or two of actually informative footage
on 02024-07-06#electroplating pennies and nickels in lime juice with spent batteries. #electrolysis #materials
on 02024-07-05#video by #NileRed explaining the Tollens silvering process. His Tollens reagent recipe is 17g silver nitrate (homemade), 2.4g soda lye, and 9mℓ concentrated ammonia: 1ℓ 0.1M AgNO₃, gravity filtration through three or four coffee filters, measure off 150mℓ, add 9mℓ ammonia solution, which with stirring soon complexes away the precipitated silver oxide into the desired diamminesilver complex; then dumps in the 2.4g of lye, and on stirring again the silver oxide precipitated dissolves. Warns of the danger of degradation to silver nitride if not used immediately, which gave some brown discoloration after a few minutes. For the mirror demonstration he shakes this at room temperature for several minutes with 1g dextrose, suggesting that a hot water bath would accelerate it. #materials #bootstrapping
on 02024-07-02#electroplating bath #materials recipe: 5% vinegar, 3% hydrogen peroxide, mixed half and half, heated in the microwave until it steams, used to oxidize a copper scouring pad to copper acetate, but don’t let the solution get too concentrated, and apply a minimum of ½V. #electrolysis #bootstrapping
on 02024-07-01#video reducing boria powder to metallic boron with magnesium powder, igniting the mix with a butane hand torch after magnesium ribbon failed. Seems to be Polish. I feel like he didn’t do a good enough job of neutralizing the magnesia and probably had a bunch in his final product. That still doesn’t quite explain the 316% yield. #materials #bootstrapping
on 02024-06-26#video on unsuccessfully attempting to oxidize SO₂ #materials with #electrolysis instead of catalysts or H₂O₂, using a platinum anode and a copper cathode. His electrolyte is dilute H₂SO₄. The hydrogen and oxygen being generated in a closed flask seems like a baad idea to me. His electrolyte turns orange, maybe because of reducing back to sulfur on the cathode. Oops, he got backflow from suckback and lost all his product. In a second run he got copper sulfide on his cathode and sulfur in the solution, which fortunately defecated. In two hours he did get the H₂SO₄ concentration up from 4% to 4.2% in his 100mℓ batch. Then he did a control test without the electrolysis and it went up to 6%.
on 02024-06-26#NurdRage #video on #bootstrapping H₂SO₄ by blowing SO₂ onto a CuCl₂ solution, which oxidizes it the same way it oxidizes PCB copper, precipitating CuCl and also producing HCl as a waste product. Then you can reoxidize the CuCl with air before switching back to SO₂. He also mentions he made a previous video using H₂O₂ to do the oxidation. #materials #scouting
on 02024-06-26another #video on #bootstrapping H₂SO₄ with oxalate and blue vitriol. #materials #scouting Deleted “for violating YouTube’s Community Guidelines”. #censorship
on 02024-06-26#bootstrapping H₂SO₄, which is apparently illegal in the #EU, but starting from the dilute stuff. #materials #video #politics #tutorial
on 02024-06-26#video on an approaching #EU ban on pure basic #materials; he’s diluting them to keep them legal
on 02024-06-25#NurdRage #video on #bootstrapping H₂SO₄ from oxalic acid (dihydrate) and ferrous sulfate (heptahydrate), and the sun, with 46–67% yield. It’s very surprising to me that this precipitates iron oxalate. He boiled down the resulting acid until the remaining sulfate started to crystallize, then distilled it to 70% of nice, colorless acid. Using more oxalic acid he got 57% yield, and by leaving the defecation beaker in the sun for eight hours to reduce ferric ions, releasing CO₂, boosting the yield to 67%. An attempt with MgSO₄ only gave 2% yield. An attempt with blue vitriol generated a precipitate too fine to filter (maybe because he added the oxalic acid too fast). He says it even works for HNO₃. #materials #scouting
on 02024-06-25#video about #bootstrapping H₂SO₄ from alabaster #materials #scouting labeled as “satire”. He’s going using washing soda for this, which initially made me think it actually was satire, but thinking about it more, it sort of makes sense: calcite is far less water-soluble than alabaster (and he gets something like 50% yield on the calcite, proving it’s calcite with vinegar). But then don’t we just get sodium sulfate (already very useful for #energy-storage phase-change materials, but not the objective)? A water-soluble sulfate is progress, I guess. He converted most of his bicarb into washing soda first, but that seems like an unnecessary step, just convenient to reduce foaming. Then he electrolyzes it at 13.12 volts and 220mA in a hot-glued-together two-chamber cell with some kind of membrane or salt bridge in the middle, using a postage-stamp-sized iron anode (!!) in the chamber of initially almost pure water and a copper chain for the cathode. His objective with the iron anode is to precipitate out the remaining carbonate. Because the current is going up, he infers that soluble iron sulfate is being formed, although sodium sulfate leaking through his salt bridge (?) would be an alternative explanation. After five hours there was a lot of green/black sludge in the anode chamber; from the greenness he infers that the iron has precipitated all the carbonate. Then he runs it through a second electrolysis using a graphite anode, which nevertheless dissolved (I feel that lead would be a better ghetto choice) and electroplated his copper with iron, which is surprising given the presumably low pH. Then he puts it under UV light in a tiny aluminum-foil chamber, which he says is to ensure no remaining SO₃ molecules. No pH or specific gravity measurement.
on 02024-06-25another #video about attempting #bootstrapping H₂SO₄ from sulfur #materials #scouting #toread
on 02024-06-25#ScrapScience #video on #bootstrapping HNO₃ #materials from KNO₃ using a terracotta flowerpot as an #electrolysis membrane with the drainage hole plugged with silicone, incorrectly described as a “semipermeable membrane”, in an HDPE container made from cutting the bottom off a plastic milk bottle. Copper cathode made from thick wire, graphite anode made from some round graphite bars. 100g KNO₃, unknown quantity of water (maybe 500mℓ), some distilled water added to the anode chamber. Initially he gets 90mA at 7.5V (=80Ω), but pretty soon that rises to 630mA (≈12Ω), and he limited the current to 1.02A. No hydrogen is generated at the cathode, surprising him, but he says it’s because the nitrate ions are reduced to ammonium. After about a day the graphite anode has been completely eaten, which makes me think it wasn’t really graphite, but like carbon arc gouging electrodes or something. The cathode compartment ended up being very basic and smelling very strongly of ammonia, so he made ammonia too. He says his crude titration (not shown) tests the acid at 0.7 molar, which apparently isn’t enough to attack copper, so he boils it with some copper in it, eventually dissolving the copper after boiling it down 4×. While this method does seem to work, it seems a little bit like a method of making an engine starting with only a car — the cheapest way to get KNO₃ is by neutralizing HNO₃ with KOH. He also thinks it “isn’t good enough to be practical” because of how dilute the product is.
on 02024-06-25#CodysLab #video on #bootstrapping H₂SO₄ #materials with the chamber process. He gets 20mℓ. #scouting
on 02024-06-25#video #toread about purifying acetone. #bootstrapping #materials
on 02024-06-20#video on phosphoryl chloride #materials (no longer accessible anonymously)
on 02024-06-15overview #video of #magnesium #materials refining, and in particular #Magrathea.
on 02024-06-12#ElAngelito #video on #electrolysis sharpening of steel wires in a stainless steel sugar bowl with a saturated table salt solution. He’s using an inverter arc welder as his power supply set at the lowest amperage. He got thick fencing wire to sharpen to a point in three or four minutes of holding it in the salt water. #materials #manufacturing #bootstrapping
on 02024-06-10#video on #electroplating: 200g blue vitriol (Zep root killer), a drop of HCl(aq) (Klean Strip concrete etchant), 50mℓ H₂SO₄ (Zep drain opener), 950mℓ distilled water, and an unspecified brightener not shown. He plates at 0.4 volts, getting about 150-400 milliamps on a Star Trek TNG communicator badge. #electrolysis #materials
on 02024-06-10#video about #manufacturing silicon #materials from sand with thermite. I didn't finish it because after the first five minutes he was still just talking to the camera. Luis Horas is not always this bad.
on 02024-06-0201950s #video of how an oil refinery works, demonstrating fractional distillation, vacuum distillation, cat cracking with fluidized-bed silica/alumina sponge, catalytic reforming with platinum supported on sapphire to raise octane, etc. #materials #bootstrapping #scouting
on 02024-05-26making quantum dot #materials using olive oil as a solvent #video #toread
on 02024-05-16#styropyro #video on #materials made from a formulary from 01933. He got a visit from the FBI because he’d bought a lot of nitrates and perchlorates and stuff.
on 02024-05-14#Nighthawk #video about waterproofing fabric #materials making oilcloth by ironing cubes of paraffin wax plasticized with mineral oil (paraffin oil, vaseline, ideally about 500mℓ per 2kg of wax) into the fabric. This seems dramatically inferior to the naphtha-thinned silicone recipe he showed previously. Contains some of the usual backwards science of Nighthawk videos; here he claims that the thermal coefficient of expansion of steel is greater than that of paraffin wax, for example, and that naphtha and gasoline are carcinogenic. For his jacket he ended up applying it as a paste wax, like to floors, but melting it with a heat gun instead of kerosene. Unrelatedly, he also demonstrates tying a slipknot (a taut-line hitch) around an acorn wrapped in the corner of his tarp in place of a tiedown grommet. Commenters advise that the wax needs to be reapplied every year; that you can filter lubricating oil out of camp fuel with nonwoven polypropylene to get naphtha; that the Hartford Circus Fire was caused by waxed fabric; and that adding about 6% by mass wood ash to the wax improves durability.
on 02024-05-03#MSDS for “Dexpan” brand #expanding-grout #materials “for controlled demolition, reinforced concrete cutting, rock breaking”, etc. Causes serious eye damage because it’s 75–90% slaked lime, also containing vitreous silica, hematite (Fe₂O₃), and alumina. But that can’t be all Expando is or it wouldn’t cost AU$15 a kilo. Specific gravity 3.2.
on 02024-05-03“Expando” brand #expanding-grout costs AU$305 for 20kg. #materials #pricing
on 02024-05-03“Expando” brand #expanding-grout generates heat that can result in steam explosions (“Do not look directly into the filled holes for the next 2 – 6 hours”!), should be poured into holes of 28mm to 40mm diameter, takes 24–76 hours to expand mostly and 5 days to expand fully, has a 10-minute working time, comes in five different formulations for different temperature ranges, and produces 14000 “psi” of compressive stress (100MPa). #materials
on 02024-05-03#HTME #video on making glass #materials #toread
on 02024-05-01#HTME #video on #bootstrapping rubber #materials from wildflowers, specifically native Minnesota goldenrod. Dried, pulverized in a blender, Soxhlet (?) reflux extraction of unwanted compounds with acetone, then solvent extraction of polyisoprene in toluene. For scaling up, improvised a reflux apparatus out of paint cans, glass tubes, and silicone caulk. Got about 3% of the mass of the dried leaves as rubber goo. Then they vulcanized the raw rubber with sulfur in a toaster oven.
on 02024-05-01#HTME #video on the lead chamber #materials process
on 02024-05-01#video #toread Cemex vs. Jesmonite #composite #materials
on 02024-04-29breaking up basalt with #expanding-grout. #materials #video doesn’t seem to say anything about what the expanding grout is made of. “Expando” brand. They drilled 149 holes with a rotary hammer about 200mm apart along crisscrossing lines about 600mm apart and then poured the stuff into them from a bucket with a funnel. Two days later the giant rock had broken into small pieces. The grout had turned white, seems to be crumbly and dusty and chalky when the hydraulic digger picks the rock apart, and seems to have expanded by on the order of 10% of its diameter. The holes where the grout couldn’t split the rock, they split with a hydraulic wedge splitter. Lots of hydraulic bucket digger action if that’s what you’re into. Bleh.
on 02024-04-06“black powder from charcoal and waste oil” (nasty used cooking oil from Abigail’s Jeep Joint food truck, and then used engine oil). #materials #video They’re using the oil to fire a 200ℓ oil drum with a charcoal retort in the middle. I like the blower design: an axial blower (maybe a microwave oven fan?) stuffed into a two-meter-long galvanized 100mm stovepipe to keep it two meters away from the fire, with an elbow at the end to stop thermal radiation. The barrel design was not optimal for burning the oil, but an old blanket as a wick helped. The air inlet must have been further off the bottom than it looked for the oil to pool in the bottom of the drum instead of running out the air inlet. Despite the #clickbait title, they also used potassium nitrate and sulfur.
on 02024-04-05#Primitive-Technology natural-draft iron smelt #materials #bushcraft #bootstrapping #video with a 1.5-meter-tall 250mm-inside-diameter mud furnace built over the course of a week with four or eight tuyeres; only got a few grams of iron
on 02024-04-05diamond in piranha. #video #materials another #The-Action-Lab video, but not full of misinformation as far as I can tell. Also includes demos of piranha on a cellulose sponge and a hot dog. Diamond results: inconclusive.
on 02024-04-04#Styropyro testing 01933 formulary recipes (part 4) #video including self-lighting matches, a potassium-permanganate black wood stain, and absolutely beautiful iridescent coal, carbon tetrachloride artificial fog, silvering a skull, bright blue flames, patching holes in metal with aluminum sulfide flash powder, etc. #formina #materials #humor
on 02024-04-03#Krasnow #Applied-Science DIYing and testing a nuclear quadrupole resonance for #materials identification #video #toread
on 02024-04-03distilling H₂SO₄. #materials #manufacturing #video recommends taping joints with teflon which can withstand the stuff at its 336° boiling point, using a stirring hotplate to eliminate bumping (boiling chips weren’t enough), using a short-path distillation apparatus, and putting the whole apparatus in a polypropylene bin (which will melt from the heat if there's a spill, but give you a few seconds to get away). He suggests sand or cat litter in the bin would contain it better. He uses differences in refractive index to detect when the new distillate is the same density as the stuff in the receiving vial. #bootstrapping
on 02024-04-03copper chloride synthesis with a spirit lamp. #Fraser just reacts muriate of lime with blue vitriol is all, why do you even need a lamp for that? Oh, he wants the copper chloride for a spirit lamp, so he can make green fire. #materials #video
on 02024-04-03producing #cooling from my pee by reacting with Birkeland–Eyde nitric acid #video #bootstrapping #materials
on 02024-04-03#Primitive-Technology #bootstrapping fired-brick hut #materials #video #bushcraft
on 02024-04-03#HTME #bootstrapping Roman concrete #materials #video; he’s using pumice from the Black Rock Desert volcanic field and pumicite (?) from a mine in California for his pozzolan. He clearly doesn’t know how to make concrete; he’s using smooth river rocks and no sand for his aggregate. Although he does use sand in his lime mortar, his cob, and presumably his modern concrete mix! Also somehow his fired clay bricks were only barely stronger in compression than his cob bricks.
on 02024-04-03decarbonating bicarbonate into carbonate #materials and then recrystallizing them. #bootstrapping #video
on 02024-04-03extracting sulfur from pyrite #materials #bootstrapping #video #toread. Ugh, now the video’s been taken private! #censorship
on 02024-04-03recrystallizing sulfur #materials bought as agricultural pesticide which are too white to be pure, using toluene as the solvent, bought from a nearby paint store. 97 grams of sulfur dissolved in 350 grams of boiling toluene, yielding 79.6 grams of purified sulfur. #video
on 02024-04-03glacial acetic acid #materials #video. Incomplete, he just purifies sodium acetate and sulfuric acid.
on 02024-04-03how to purify acetone #materials #bootstrapping #video #toread
on 02024-04-03high-entropy metals as alternative alloys to steel #materials #video
on 02024-04-03problems with contaminated acetone #materials #bootstrapping #video. Explains the systematic nomenclature with butanone, dimethylketone, aldehydes, etc. Then he does a fractional distillation to compare Spanish brands. Leroy Merlin acetone, which he describes as “caca de la vaca”, has at least 4% contaminants. Brico Depot had reasonably good quality. Also the paint store next to his house. Misogynist jokes.
on 02024-04-03extracting iodine from povidone iodine #materials #bootstrapping #video #toread
on 02024-04-03piranha solution recipe #materials #video. fairly spectacular demonstration of how it annihilates cotton, sugar, latex, nitrile, old T-shirts, etc.
on 02024-04-03why is sulfuric acid the king? #materials #video
on 02024-04-03#Alpha-Phoenix first-surface mirrors. #optics #video he’s using the silvering process from the Tollens #materials test (silver nitrate, lye, ammonia, and a reducing sugar). Probably this process would be useful for #electroplating non-conductive objects as an alternative to graphite paint. He prints some things in an unspecified plastic with FDM #3D-printing, sands them, applies a two-part epoxy filler (“XTC-3D”) to smooth the surface, and silvers it by spraying precursors from a commercially-bought silvering kit onto it. To keep the resin from dripping off before it cures, he rotates a part slowly on a slanted axis so that it drips back to where it started. This introduced errors far too large for #optics. To try to silver the surface evenly he added a surfactant. In one batch, his epoxy reacted with one or more of the sprayed precursors, getting silver but with a terrible surface finish. In fact, that kept happening afterwards; he found that he had to cure the resin indoors (heat? humidity?) and needed to have the resin component ratio skewed toward component “A”.
on 02024-04-03DIY metal #3D-printing (SLM of 316 stainless) #bootstrapping with a 155-watt #laser coupled in through a fiber running at up to 300mm/s, getting better results at higher speeds and higher powers. Wow, I had no idea that surface tension gradient with temperature was a thing, but apparently you can reverse it by adding sulfur to stainless, resulting in a reversal of Marangoni convection! Eventually his 3-D printed ASA lens housing overheated and hazed his lens and fiber. #materials #video
on 02024-04-036 #materials processes that “changed the world”: #video of apparently 100% talking-head and stock footage garbage by "Breaking Vlad"
on 02024-04-03the world’s 8 most produced #materials by #BreakingVlad: H₃PO₄ (83 million tonnes per year), Cl₂ (97 million tonnes per year), NaOH (100 million tonnes per year), N₂ (120 million tonnes per year), C₃H₆ (150 million tonnes per year), NH₃ (176 million tonnes per year), C₂H₄ (223 million tonnes per year), and H₂SO₄ (233 million tonnes per year). Shitty talking-head #video repeating bullshit with stock footage.
on 02024-04-03#manufacturing acetone #materials from eggs by eating the shell with vinegar to make INS 263 and then dry-distilling it. He says he got 20% yield. He started by cooking the shells to burn up the organics, but not really enough, so he only succeeded in charring them, which he regrets and doesn’t recommend; it made the whole process smell unbelievably terrible until he removed the waste products. After weeks of digestion in vinegar, he added activated charcoal from a water filter in the middle, decanted it, strained it through a screen, filtered it through a cotton ball, and got a brownish transparent solution. After a second decantation step he let it dry for a few more weeks to crystallize acetate crystals in bizarre hollow cauliflower shapes. I think he probably could have purified it a bit at this stage by only doing a partial crystallization, but he let it dry completely. Then it rehydrated from the air and became soft, no longer stinking of burnt corpse. He says it requires about 400° to decompose, not 160° as Wikipedia says, so he had to switch from his hotplate to a heating mantle he made from plaster and a hair dryer heating element, which burned out immediately, so he made another one. The distillation then produced a flammable orange liquid, probably mostly acetone. Naturally his shitty plaster heating mantle started crumbling. Perhaps he wasn’t cooling his distillation enough, because he lost a lot of white vapor, though he says it was side products. Because the heating mantle reached red heat, his borosilicate round-bottom flask melted somewhat, cracked from the temperature gradient, and melted some holes in the bottom. As a replacement distillation vessel, he drilled an empty butane cylinder (underwater to keep the drillbit cool and prevent air from contacting any potential sparks), filled it with water to drive out the butane, then drilled bigger holes and used it as his dry distillation flask. To purify the orange acetone, he started with fractional distillation, getting a light yellow acetone. Cleaning the distillation flask was very difficult, requiring not just a base bath but sanding. For a second fractional distillation of the yellow stuff he used a hotplate oil bath and 500mm of distillation column, wrapped in aluminum foil, obtaining almost colorless acetone. A third fractional distillation removed the remaining color, but it still smelled burnt. So naturally he refluxed the acetone with a giant quantity of KMnO₄ for 15–20 hours, then did another fractional distillation to get the acetone back out, at long last eliminating the burnt stench. Then he tried another purification with aqueous silver nitrate and sodium hydroxide as recommended in Vogel’s “Text-Book of Practical Organic Chemistry”, third edition, leaving a black gunk in his flask which had to be cleaned with nitric acid. Another fractional distillation removed most of the water, and finally calcium sulfate hemihydrate removed the remaining water, though not before he broke his hotplate and his camping stove trying to dry the sulfate. An additional distillation separates the dry acetone from the plaster. Then to try to get the yield above 20% he tried re-purifying some of the fractions discarded during the various distillations with the silver-oxide method mentioned earlier, followed by KMnO₄, at which point he regretted adding so much at once, because the acetone started boiling from the reaction before he could dunk the erlenmeyer in a water bath, at which point he gave up. #bootstrapping #video
on 02024-04-03#HTME #bootstrapping H₂SO₄. There’s a natural source in Yellowstone which he didn’t use; instead he used sulfur collected from an old sulfur mine in Death Valley which exploded in 01953. He planted red cabbage in raised beds earlier to make anthocyanin as an indicator (but also used commercially made four-dye pH test strips). He tried dry distillation of blue vitriol and green vitriol to get H₂SO₃ (pH 5–6) and then waits (the dry distillation took weeks). For the dry distillation he cheated by making a still out of steel pipe, because this was shortly after the workshop fire. Then he boiled it down to get a pH of 2. But even at a pH of 0.5, industrially produced H₂SO₄ doesn’t dissolve chicken wings, though it does at pH -1.27. Heating pyrite in water to oxidize it reached a pH of 3 after several years. #materials #video
on 02024-04-03#manufacturing DDNP poof-powder #materials (01969 Army field manual procedure) #video
on 02024-04-03#manufacturing ethane (R170) #materials for refrigerant (for the second stage of a cascade). His R600a tabletop icemaker compressor was able to condense CO₂ and N₂O despite only reaching 10 bar, but only barely handled ethylene, which he had made by running ethanol through Al₂O₃ at 450°. So he’s making ethane by Kolbe #electrolysis of sodium acetate on a platinum anode, liberating CO₂, which he has to remove with a Ca(OH)₂ scrubber. To avoid producing lye and thus oxygen, he includes an excess of acetate, in the form of vinegar; he got a weird oil making the sodium acetate. He uses ABS putty dissolved in acetone to seal his electrolysis electrode junctions inside an ABS sleeve he 3-D printed. He switched to using a float switch because his conductivity probe made of two stainless-steel screws was failing, maybe because of the oil. Includes Faraday calculations from first principles. Demonstrates burning soap bubbles of C₂H₆/CO₂ squeezed out of a syringe. He didn’t use enough vinegar, so his pH rose to 9.6, meaning that this process is an effective way to make alkali (probably Na₂CO₃, as evidenced by CO₂ bubbles when he adds more vinegar), since the anion turns into gas. With the pH at 5.6 he got 1.08ℓ/hour of gas from 700mA, close to the theoretical 0.94. His scrubber and gas drier are two packed-bed jam jars with pipes and hoses glued onto their lids and bases, sitting on 3-D-printed supports. By spraying liquid ethane all over the place after precooling it to -12° with his first refrigeration stage, he gets to -90°. He thinks a PbO₂ anode would work too. #video #Hyperspace-Pirate
on 02024-04-03#Backyard-Scientist gallium versus a high-pressure compressed gas bottle: gallium wins #materials #video
on 02024-04-03incorporating metal turnings into fired-clay #ceramics makes blurry red and black spots in the glaze; further reduction firing in gas produced blotches of iron and copper on the surface. Later he has to Dremel the bases a bit because his glaze stuck to the “wadding” feet he had stuck on there. #materials #video
on 02024-04-03thermite #materials powered hotdog heater by #Thought-Emporium #video #liststart
on 02024-04-03Hansen #solubility parameters #materials
on 02024-03-26Hildebrand #solubility parameters #materials
on 02024-03-26Hildebrand vs. Hansen #solubility parameters #materials
on 02024-03-26nanoporosity in #3D-printing #materials made from nickel prevents dislocations from propagating and thus increases strength
on 02023-09-22this #adobe #materials #construction #paper #PDF on Aveiro district in #Portugal cites the “2009 New Mexico earthen building materials code” and found mean compressive strengths in Aveiro from 0.66 MPa to 2.15 MPa, with modulus of elasticity from 50-450 MPa and tensile strengths from too low to measure up to 0.40 MPa (typically 10-20% of compressive strength), with rather astonishing strains at peak stress of 5-10%. Adobe from Colombia and Morocco was much stronger. #strength-of-materials
on 02023-07-08thermodynamic properties of aluminum phosphate. #materials
on 02023-07-02a reformatting of most of the Haver, Bixby, and Wong report about #lead chloride #materials #electrolysis and #hydrometallurgy
on 02023-06-17Haver, Bixby, and Wong published Bureau of Mines Report of Investigations 8276, “Aqueous #Electrolysis of #Lead Chloride”, in 01978, as part of the US Department of the Interior. They leached galena with aqueous FeCl₃ and NaCl at 100° to get #materials solid #sulfur and lead chloride (which is reasonably water-soluble at this temperature). They were able to reduce the PbCl₂ to metallic lead through electrolysis, either in molten salts (which requires less energy) or in aqueous solution. “Optimum results [for the #hydrometallurgy process] (96-pct current efficiency, 0.23 kwhr[sic]/lb Pb) were obtained with 20 pct HCl at 25° C, using a current density of 15 amp/ft² and an electrode spacing of one inch.” They also got reasonable efficiency at up to 20× higher current densities. Apparently the NaCl functions as a catalyst. They purified the “pregnant solution” by passing it over lead shot before cooling to remove silver, copper, and antimony. If they did the electrolysis in the “spent” leach solution, the FeCl₂ in it would reabsorb the chlorine thus produced and become FeCl₃. They used a graphite anode and a lead cathode at the bottom of the electrolysis cell. For the molten-salt process they centrifuged out the PbCl₂ and reabsorbed gaseous Cl₂ into the stripped spent leach solution in an absorption tower for recycling back into the leach tank.
on 02023-06-17Carolyn Moorlag's 01997 master's thesis #paper #PDF on reacting alumina #materials with phosphoric acid and other #phosphates in a #sol-gel process to produce CBC #ceramics, surveying a lot of the work since Kingery's original explorations. She talks about composite sol-gel ceramic systems (with majority ceramic inert functional #fillers), and mentions that for "metal-matrix composites" the ceramic-reinforcement/phosphate binder mix is cured at 400-900° and then infiltrated with metal.
on 02023-06-11a kilogram of sodium metasilicate #waterglass costs 140 rubles. #materials #pricing
on 02023-03-10#paper from 02006 on foaming soda-lime glass into an 0.35 g/cc #glass-ceramic foam at 750° after hydrating the #glass powder (half less than 138 μm, a third less than 63 μm) in hot water at 200° for six hours. DOI 10.1016/j.jeurceramsoc.2005.07.041. #foam #materials
on 02023-03-09#PDF on #mineral commodity summaries: #magnesium, 02022. Prices went as high as US$15k per tonne because the Utah plant shut down due to equipment failure, and power problems in #China limited production there. But normally it’s more like US$3k. #materials #pricing
on 02023-02-28one-page #PDF of data about #tachyhydrite CaMg₂Cl₆·12H₂O, associated with kainite, carnallite, sylvite, halite, kieserite, bischofite, and anhydrite. #deliquescent #salt #mineral #materials
on 02023-02-28photos and summary information about #tachyhydrite CaMg₂Cl₆·12H₂O #deliquescent #salt #mineral #materials
on 02023-02-28the other endmember of plagioclase feldspars. #mineral #materials
on 02023-02-28a plagioclase feldspar endmember #mineral that is abundant in moon rocks. #materials
on 02023-02-28CorningWare was a line of cookware made from an opaque white #spodumene based #glass-ceramic called "Pyroceram" that could be used directly on fire, which was both less expansive from heat and I think stronger than borosilicate glass. No longer available for sale in the US, making it a lost technology of the ancients, but only since 02022. #materials #collapse
on 02023-02-09#materials properties database for a #MEMS class at MIT in 02004, with density, Young's modulus, Poisson ratio, thermal and electrical conductivity, dielectric constant, index of refraction, etc., for a variety of materials commonly used in MEMS
on 02023-01-15#gelation of #carboxymethylcellulose with Fe⁺⁺⁺ cations (in FeCl₃) to form #hydrogel microparticles; mentions Ca⁺⁺, Ba⁺⁺, and Zn⁺⁼ can also “cause aggregation and even precipitation” but no gel formation, while Al⁺⁺⁺ can cause gelation. “We would therefore expect the gels generated with this system to be much more spatially homogeneous than those of Ca-alginate.” #materials
on 02022-09-292-D polymer #materials "2DPA-1" by Yuwen Zeng
on 02022-02-09introductory #materials #textbook from 01954
on 02022-02-09glutaraldehyde, 5 ℓ 2.5% for AR$2800 #materials #pricing
on 02021-12-20explanation of Young’s modulus and where it arises from in #steel #materials
on 02021-09-17melting points of metal #materials
on 02021-09-06#paper on #mechanical properties of #seacrete #materials as a possible replacement for #concrete, describing it as “electrolytically precipitated calcium carbonate”
on 02021-09-06#art #history article on primary-color pigments in paint #materials
on 02021-01-19How #graphitization produces #graphite with Carbolite furnaces, of which the high-temperature regions are made 100% of graphite (including graphite felt insulation and graphite heating elements) and thus must be protected from feedstock outgassing and, of course, filled with argon or vacuum when hot. The thermocouple is withdrawn at 1200° and further temperature control is pyrometer-only. #materials
on 02020-12-20this #paper reports on production of #graphite, normally made by the Acheson Process (heating amorphous carbon at 3000°). They achieved almost complete or complete #graphitization (the paper repeatedly contradicts itself on this point) in 5 minutes by microwave-heating activated charcoal (mesh 100–325, 600–1500 m²/g) to 1000° after ethanol-impregnating it with 6 mmol NiCl₂ (per gram of carbon, mysteriously resulting in 15–35% wt% Ni), which produces a metallic nickel catalyst which can dissolve a little carbon (2.7% at 1327°), which then precipitates as graphite. They did this under argon in a quartz reactor over total processing times of 35–60' to allow 30' to heat up to 1000°. They report that microwaves’ penetration depth into graphite is only a few microns. They report both that the Acheson process takes two weeks and that they achieved full graphitization by heating various feedstocks to 3000° without catalyst for a few minutes. #materials
on 02020-12-20nickel hyperaccumulator plants like Alyssum murale and Phyllantus balgoyii and, in Indonesia and Malaysia, Sarcotheca celebica and Knema matanensis (and 400+ other species) can be used for #nickel #mining, even in soils that are 0.1% nickel rather than the traditional 1% limit for economically recoverable resources. #materials
on 02020-11-18debunking of the stupid #rare-earths scaremongering by Amory Lovins. #materials #economics
on 02020-11-18superhard #materials include diamond (especially aggregated diamond nanorods, “hyperdiamond” or “nanodiamond”), γ-boron, maybe cubic boron carbon nitride, cubic boron nitride (CBN or borazon), borides of osmium and rhenium and ruthenium and tungsten, boron carbide, and the ultraslithy BAM (aluminum magnesium boride). Carbon nitride has not yet materialized.
on 02020-11-18notes on #materials properties of #desiccants and other salts
on 02020-11-12another page on traditional #qualitative-analysis of inorganic #materials
on 02020-11-12Traditional #qualitative-analysis of inorganic #materials, now only of pedagogical use (well, and #bootstrapping maybe)
on 02020-11-12notes on chalcogenide oxygen-free glass #materials, which are useful for IR #optics because they're transparent to LWIR and MWIR, which the silicon-oxygen bond slurps up
on 02020-11-12#ebook about #materials. #CC BY-NC-SA 3.0
on 02020-11-12introduction to #materials strength, Young's modulus, etc., by Helmut Föll, as a hypertext
on 02020-11-12how to anneal mild #steel sheet #materials
on 02020-11-11Notes on tool #steel formulation, hardening, tempering by oxide interference color, temperature by incandescence color, Rockwell C hardness by tempering, etc., “from the perspective of a woodworker” #materials
on 02020-11-11waterglass plus magnesium salts gives an amorphous talc adsorbent used as a food additive to, say, keep salt from clumping. #materials
on 02020-11-11how ion exchange resin #materials work for purification
on 02020-09-25a handy list of common solvents by dipole moment #materials
on 02020-09-24introduction to the metal reactivity series in #materials
on 02020-09-23Common sources for exotic #materials supplies in the USA.
on 02020-06-20#video on simplified #electroplating (copper, nickel, or zinc) with vinegar and salt. Comes strongly recommended. #materials
on 02018-11-04Why #laser-cutter work has trouble with plywood #materials, and how Nervous System commissioned their own custom plywood.
on 02018-08-16How cast iron cookware works, including a bit of #materials science and reactions
on 02017-07-11review #paper on silica-alumina #refractory ceramic #materials, including particularly mullite
on 02017-05-19technical data on insulating firebrick #refractory #materials has bricks that are good up to 1260° to 1649°, specific gravity from 0.58 to 1.03, modulus of rupture from 0.85 to 1.52 MPa, crush strength from 1.8 to 2.5 MPa, thermal conductivity from 0.18 to 0.44 W/mK, varying significantly with temperature. Less dense bricks are less conductive, weaker, and, surprisingly, resist lower temperatures — the last presumably because of a higher silica-to-alumina ratio.
on 02017-05-19technical data on insulating firebrick #refractory #materials that I can’t be bothered to summarize here because it’s all in Imperial units
on 02017-05-19intense ultraviolet radiation (UVC) gradually damages silicon photodetector #materials
on 02017-05-09A list of common bond energies and bond lengths of #materials.
on 02017-03-29#video by clkindred of a homemade coffee can forge with about 10cm of homemade castable refractory (perlite, plaster of paris, and sodium silicate #materials) and a homemade stainless steel gas-fueled (propane?) burner modeled after the one in his camp stove. The gas orifice is an 0.016" hole drilled in a ⅛" NPT plug coupled to a ⅛" hose barb with a standard pipe coupler. The stainless-steel burner tube is from an apple corer. He seems to be getting to 1100°, guessing from the incandescence color. He seals the surface of the perlite with a cement of sodium silicate, talc, and corundum abrasive, with a slight amount of plaster of paris as an accelerant, to have a kind of hot face. (I’m sort of surprised the perlite isn’t melting.)
on 02017-03-22silicon carbide #materials work as semiconductor #hardware at above 250° and can therefore make electronics that would survive on the surface of Venus (for 521 hours in one simulated-Venus test).
on 02017-03-15frits: #glass powder #materials for #ceramics
on 02017-03-11a short #history of red #pigment #materials
on 02017-02-24#ceramics #materials: ball #clay
on 02017-03-07different aspects of #ceramics vitrification: how to test porosity, etc. #materials
on 02017-03-07#ceramics #clay info from #ebook “Clay #materials for the self-reliant potter”. Seems like the actual recipes are missing, though.
on 02017-03-07#PDF of Flumerfelt’s 1998 dissertation on #aluminum #powder-metallurgy #materials processing; he finds that synthesizing his aluminum powder with gas atomization reaction synthesis ("GARS") was superior to existing commercial products, which were powdered by air atomization or gas atomization. Mentions that sintering aluminum powder in air has been shown to be possible but difficult by Storchheim (or maybe Storcheim) in 1974, in a paper called “Air sintering improves aluminum P/M economics”.
on 02017-03-02#paper on #sintering #piezoelectric #ceramics #materials at lower temperatures using lead oxide as a sort of flux or binder
on 02017-03-02#PDF #paper on #TCE, thermal coefficients of expansion, of different kinds of #glass #materials; B₂O₃ and MgO are 0.33 ppm/K at human temperatures, silica is 2.67, PbO and TiO₂ are 13, CaO and Al₂O₃ are 17, K₂O is 28, Na₂O is 33. Also they did their own linear regression, giving rise to a hairier model that is apparently twice as accurate. PbO’s 13 compares favorably to (from other sources) carbon steel at 10.8, aluminum at 23.1, and concrete’s at 12, but of course enormous compared to invar at 1.2 or crystalline quartz at 0.33.
on 02017-02-23Mycalex #materials apparently cost US$825 for a 14×20×0.062 sheet of the low-temperature (400°) version. I guess those are inches?
on 02017-02-09#paper where Norman M. P. Low fabricated composite #materials by binding powdered mica with soda-lime glass and firing at 850°. I think this is the basis for the Mycalex/Mykroy machinable ceramic, although that uses E-glass. June 1980, Volume 15, Issue 6, pp 1509–1517, “Fabrication of cellular structure composite material from recycled soda-lime glass and phlogopite mica powders” #toread
on 02017-02-09patent for sintering #glass #materials into #ceramics at only 750° by wetting 100-mesh soda-lime glass powder with PEG-8000 as a binder dissolved in isopropanol, drying it at 60°, dry-pressing it at 5000 psi (34 MPa) and then firing it. Apparently the absence of water in the process avoids foaming during firing. #patents
on 02017-02-09The 1995 Lackner-Wendt “auxon” #paper on #self-replicating robots, “Exponential growth of large self-reproducing machine systems”. Particularly interesting: “Carbon plays a special role because it becomes gaseous when oxidized and, as a result, its reducing power increases steadily with temperature. It is moderate at low temperatures but at 2200°C carbon reduces all the other common elements.” If I understand the diagram correctly, the last one it crosses is CaO, crossing Al₂O₃ just a bit below, around 2000°. However, their proposed element separation cycle is a bit more complex than that would suggest. Does this really imply that you can smelt aluminum by heating alumina above 2200° inside charred bread? There are two footnotes about industrially-feasible carbothermic aluminum reduction, but unfortunately they’re in a 1988 conference proceedings. Fortunately, there is more recent research. #materials
on 02017-01-24#PDF #paper on properties of #charcoal #materials, finding reasonably high conductance (.76 and .5 Ω·cm for cypress charcoal, which I guess is 5 to 8 mΩm, pretty decent conductivity).
on 02017-01-24#paper saying that a packed bed of #charcoal (i.e. carbonized biomass) particles under 8 MPa of pressure can have reasonably low resistivity: they say “σ < 0.2 Ω·cm”, which I guess means 2 mΩm, which is pretty low but higher than pyrolytic carbon #materials. Also, it says heat-treating 1050° lowers the resistivity by five orders of magnitude.
on 02017-01-24apparently different vegetable #charcoal #materials have resistivities in the neighborhood of 10 to 20 mΩ·m, almost 1000 times higher than pyrolytic graphite or amorphous carbon, but still low enough to be practical as electrodes. #data
on 02017-01-24amorphous carbon #materials resistivity #data: 15 to 46 μΩm, slightly more conductive than pyrolytic graphite, and also in the neighborhood of metal conductors.
on 02017-01-24#pdf on pyrolytic graphite or pyrolytic carbon #materials, giving in particular a resistivity of .5×10⁻³ Ω·cm, which I guess means that if you have a 10 cm × 1 cm × 1 cm block of it, the resistance is .5 × 10⁻3 Ω·cm · 10 cm / 1 cm / 1 cm = 5 mΩ of resistance, which is in the neighborhood of metal conductors. .5×10⁻³ Ω·cm would be 50μΩm.
on 02017-01-24Hmm, if you dissolve corundum in lye in a steam-heated nickel or steel vessel (near 100° I guess) you get NaAlO₂, which 1.5 g/cc, soluble in water and alcohol, but doesn’t melt until 1650°. It’s an intermediate in aluminum smelting, since the rest of the bauxite won’t dissolve in lye. Hygroscopic but not deliquescent. #materials
on 02017-01-17you can make terra cotta #ceramics #materials almost as strong as stoneware by adding frit to fill the pore spaces with glass
on 02017-01-17#PDF #paper “Effect of firing temperature on sintering of porcelain stoneware tiles”, 2008 says porcelain #materials are typically 50% kaolinite, 40% feldspar (potassic, as a flux I guess), 10% quartz (as a temper). Mentions “60–90 min cold-to-cold” for “porcelain stoneware”, which is very exciting. “Heated for ~30 min [to 1200° or 1280°]...soaked for 15 min, and then cooled in the furnace at 50°C/min to room temperature”.
on 02017-01-17notes on “metal clay” #materials, which are plasticized sinterable metal particulates
on 02017-01-17#pdf of a 1936 #paper on #refractory #ceramics #materials properties
on 02017-01-16tips on wollastonite for #ceramics #materials
on 02017-01-16#materials properties for engineering porcelain #ceramics
on 02017-01-16an excerpt from “The Self-Reliant Potter”, “a ceramic book specifically to suit conditions in developing countries originated from my [Henrik Norsker’s] personal experience and associated problems whilst I was struggling to set up modern pottery production in a Tanzanian village ten years ago [before 1985]” on #refractory #materials and techniques. #ebook
on 02017-01-14more #refractory #materials recipes
on 02017-01-14a castable #refractory recipe that recommends using calcium aluminate cement rather than portland. #materials
on 02017-01-14another discussion thread on recipes for castable #refractory #materials
on 02017-01-14discussion thread on recipes for insulating #refractory bricks for #ceramics kilns. #materials
on 02017-01-14a recipe for castable #refractory made with wollastonite and phosphoric acid, generating calcium phosphate (hydroxyapatite, like bone) and amorphous silica. Supposedly doesn’t melt until 1670°; the phosphate acts as a cement. #materials
on 02017-01-14castable #refractory #materials recipes for a kiln for soda-vapor #ceramics
on 02017-01-14explanation of grog, with photos of some spectacularly grog-tempered pots. #ceramics #materials
on 02017-01-03a #paper on how plasticity of #ceramics clay #materials changes with #moisture, explaining Atterberg limits and whatnot
on 02017-01-03Mitsubishi’s 1994 metal clay patent for sintered precious metal #materials: 50% to 90% precious metal (in particles of under 200μm), 0.8% to 8% water-soluble cellulose binder (methylcellulose or ethylcellulose), 0.08% to 3% surfactant (soap; recommended polysoap or alkyl benzene sodium sulfonate), 0.1% to 3% oil, remainder water. Also mentions boiled rice or wheat flour as previous binders, but says the cellulose burns off and discolors the metal less. The oil is to keep it from sticking to your hands; suggests di-n-butyl phthalate, PEG, PVA, etc. Also says ethylene glycol enhances moldability. The cellulose gels during heating. I bet you could use this binder for non-clay #ceramics like zirconia and alumina, too; and I bet other water-soluble polysaccharides like mucilage would work.
on 02017-01-03#PDF on separating different clay #materials from the 1960s.
on 02017-01-03Cody Reeder (“Cody’sLab”) successfully mining a gram or so of #aluminum from aluminum silicate clay: he pulverizes by beating on a plastic bag, allows a water slurry to settle to separate out the clay, adds hydrochloric acid to solubilize the aluminum as aluminum chloride, allows the silicates to settle, neutralizes the liquor from the top using sodium hydroxide drain cleaner to get insoluble aluminum hydroxide, washes it to remove iron hydroxides, calcines it at 1000° to get alumina, dissolves it in a graphite crucible in store-bought cryolite, electrolyzes the solution with a plug-in 200-amp car starter connected to a preheated carbon electrode, and then breaks up the hardened poured mass to find native aluminum particles, in the Utah snow. #materials #materials #video
on 02016-12-23Cody Reeder (“Cody’sLab”) successfully mining a gram or so of #aluminum from aluminum silicate clay: he pulverizes by beating on a plastic bag, allows a water slurry to settle to separate out the clay, adds hydrochloric acid to solubilize the aluminum as aluminum chloride, allows the silicates to settle, neutralizes the liquor from the top using sodium hydroxide drain cleaner to get insoluble aluminum hydroxide, washes it to remove iron hydroxides, calcines it at 1000° to get alumina, dissolves it in a graphite crucible in store-bought cryolite, electrolyzes the solution with a plug-in 200-amp car starter connected to a preheated carbon electrode, and then breaks up the hardened poured mass to find native aluminum particles, in the Utah snow. #materials #materials #video
on 02016-12-23How wood’s equilibrium moisture content depends on relative humidity. #materials
on 02016-12-2165 pounds of excelsior costs US$183 at retail, US$6.20/kg #materials
on 02016-12-21Carved nephrite #minerals are tough enough to make fishhooks and bladed weapons like the mere from. Nephrite, Ca₂(Mg, Fe)₅Si₈O₂₂(OH)₂, is an actinolite amphibole; it contains slightly more silicon than #enstatite, and also contains calcium and hydroxyls, which enstatite doesn’t. How would you go about synthesizing nephrite? Especially without accidentally creating asbestos? #materials
on 02016-12-16A terribly amusing article about explosive #materials, from Derek Lowe’s “Things I Won’t Work With” series.
on 02016-12-07#CodysLab #video where he oxidizes aluminum with lye with a teakettle and fishtank to separate hydrogen and distills it out. #materials #bootstrapping
on 02016-10-10#CodysLab #video with beekeeping, chokecherries, and flame-cutting and #welding steel with an oxyhydrogen torch. And MELTING TUNGSTEN. And a crude version of the Birkeland-Eyde process, assayed with calcium carbonate. #bootstrapping #materials
on 02016-10-10Ethanol and water form a #eutectic at about 94% ethanol, freezing at about -118°. #materials
on 02016-09-16#pdf #paper on the physical properties of possible liquid metal coolant #materials for a nuclear reactor, including sodium, lead, and lead-bismuth eutectic.
on 02016-09-11a chart of different kinds of #adhesives #materials for #manufacturing
on 02016-09-11Comparing #MDF to balsa wood in a #materials database
on 02016-08-16Apparently because the Romans didn’t have nitric acid, they separated silver from gold by smelting finely divided electrum with salt to produce silver chloride. Silver chloride is capable of producing photographs! #materials #history
on 02016-07-24The earliest recipe for the acid needed for the acid test for gold is from the 13th century, calcining alum, niter, and what I suppose is chalcanthite. #materials #history
on 02016-07-24“Multifunctional Stiff Carbon #Foam Derived from Bread” by Ye Yuan, Yujie Ding, Chunhui Wang, Fan Xu, Zaishan Lin, Yuyang Qin, Ying Li, Minglong Yang, Xiaodong He, Qingyu Peng, and Yibin Li. They baked bread (though they didn’t specify what kind of flour they used), oven-dried it, and pyrolyzed it under argon in a tube furnace at 500° and 2000° (the 2000° version removed more organic material, although I imagine you could wrap it in aluminum foil instead for up to 660°, or bury it in sand up to 1600°). 3.6 MPa compressive strength, 0.08–0.29 g/cc, 121 MPa compressive modulus, .06 W/m/K thermal conductivity, surface areas from 988 m²/g for large and irregular pore structure down to 19 m²/g. #materials
on 02016-07-19Constantan has a zero temperature coefficient of resistance (or I guess resistivity) because it incorporates Weston’s Alloy No. 2, which has a negative temperature coefficient of resistance. Or something? I don’t quite understand. This is what Thwaites tried to use for #bootstrapping his toaster heating element because Erin Brockovich scared him away from chromium. #materials
on 02016-07-07Idiot fishermen don’t realize fishing line’s strength is proportional to the square of its diameter rather than to its diameter. This may explain some of the anomalies I saw in the strength ratings in the fishing store. One fisherman correctly complains about its lack of elasticity. (I’m investigating #UHMWPE line.) #materials
on 02016-07-01Pure Fishing’s Berkley brand’s Whiplash Orange fishing line is “100% PE #Dyneema” (i.e. #UHMWPE) fishing line. From their UK website, it costs £0.1166 per meter on a 300-meter reel in the diameter range 60μm to 200μm. They have some larger; 280μm, the thickest they offer, is rated at 44.9kg breaking strength, and they charge £42.99 for 220m, or £0.1954/m, or £279.99/2000m = £0.14/m. 44.9kg is 440 N, coming out to a stunning 7.15 GPa tensile strength, almost three times the rated strength of the 50kg 500μm “Whiplash Pro” of which I bought 100 meters for AR$100 the other day (AR$1/m ≈ £0.15/m). They no longer seem to carry “Whiplash Pro.” #materials
on 02016-07-01Where to get fireclay #materials
on 02016-06-30“Homesteading and permaculture, all the time”. Forum thread about castable #refractory formulations for rocket stoves and whatnot. #materials #hardware
on 02016-06-30Soapstone (#talc) “evaporator” humidifier, plus a soapstone trivet and soapstone-topped stove #video #materials
on 02016-06-30how #materials such as polycarbonate and nylon change their modulus and strength with temperature
on 02016-06-29Holy shit, you can smelt silicon out of sand by reducing it with aluminum, ignited with an aluminum-sulfur reaction and magnesium strips. #materials #video
on 02016-06-29This guy did some #science with some different sail #textile materials and found that #Tenara was the only one that wasn’t badly degraded by a couple of months of humidity and UV. #materials
on 02016-06-28#Tenara PTFE thread on Amazon: US$120 per spool, 8 ounces, 1150 yards, 19 pounds breaking strength. Not sure what the density or diameter is, though. #materials
on 02016-06-28"Tenara" is an architectural #textile woven of expanded polytetrafluoroethylene (PTFE, teflon) fibers, with a lifetime of 25 years or so in the sun. #architecture #materials
on 02016-06-28“Thrombosis remains a significant and potentially catastrophic complication of #polyethylene-terephthalate (Dacron) prosthetic vascular graft implantation.” Not clear whether boiling it in lye actually helped. #materials #science #medicine #paper
on 02016-06-28#basalt rebar #materials by the Neuvokas company. Claims price parity with steel.
on 02016-06-26#Concrete #materials suffer #carbonatation more rapidly in today’s 400ppm CO₂ climate, and some #architecture designed for 75 years will start to fail in 50 or 60.
on 02016-06-26Another #basalt fiber #materials supplier in Russia.
on 02016-06-26#Basalt rebar #materials supplier in Russia.
on 02016-06-26#Basalt rebar #materials; also basalt fiber twine, basalt chopped fibers, and basalt fiber #textile fabric. “89% lighter” than steel. “naturally resistant to alkali, rust and acids.”
on 02016-06-26Expanded vermiculite for gardening for AR$20 per bag (of 300mm×200mm×???, looks like two liters or so?) #materials
on 02016-06-22Super-mega virgin high-density #polyethylene #geomembrane of 800 μm costs AR$629 per 7 m²; it comes in 7m×100m rolls, so you can get humongous sheets of it, although you need to plastic-weld it as shown if you want to do a waterproof installation of more than 7m width. #materials
on 02016-06-22Transparent 200-μm #polyethylene film is pricier than the black, probably because it’s not recycled: AR$1289 per 2m×50m roll (AR$12.89/m²). This is also for agricultural use; it’s not especially stretchy or sticky. It would be suitable for reducing airflow around a solar heat collector, if you don’t mind replacing it every month or two. #materials
on 02016-06-22black 100-μm #polyethylene film (presumably recycled) for agricultural use costs AR$440 for a roll of 2m×100m, AR$2.20/m², even cheaper than paper. #materials
on 02016-06-22Black 200-μm recycled #polyethylene film for agricultural use costs AR$1288 per roll, 4m×50m, for AR$6.44/m²; weighs 22kg, so that’s AR$58/kg. Sold retail by Ferretería Pompeya. #materials
on 02016-06-22Also you can buy green recycled high-density #polyethylene for AR$20/kg in 25-kg bags. #materials
on 02016-06-22Pelletized recycled high-density #polyethylene costs AR$20/kg in 25-kg bags. #materials
on 02016-06-22anhydrous sodium sulfate for sale, Pagrun brand, AR$10 per 25 kg. WP says it costs US$90 per tonne (“for salt cake quality”), which would be US$2.25 for 25 kg, which would be about AR$32; not sure why it’s cheaper here. The local price here works out to 2.9¢/kg. Selling it to someone who isn’t a chemistry lab is technically illegal in order to cut down on drug trafficking. The vendor seems to be some kind of salvage, recycling, or auction place; their other sales are largely car parts and air conditioners. #materials
on 02016-06-14#PDF properties of #UHMWPE #materials, including volumetric abrasion (compared to many other chemicals), coefficients of friction, and density.
on 02016-06-02properties of common #materials including nylon, UHMWPE, composites, metals, ceramics.
on 02016-06-02properties of a variety of #materials used in composites, including #UHMWPE.
on 02016-06-02#pdf #paper on #Dyneema #UHMWPE #materials properties (Young’s modulus, tensile strength at varying strain rates, etc.)
on 02016-06-02A 60-watt #laser-cutter at 50% power and 300 mm/second (?!) can engrave marble at about 150 to 200 dpi. #materials
on 02015-11-30Delrin (acetal) #materials properties and design guide #manufacturing #pdf
on 02015-11-30a surprisingly comprehensive overview of electric motor #hardware #history and energy efficiency, from the point of view of Hitachi, in #pdf. Includes overview of metal glass Fe-Si-B super-high-#permeability #materials, which beat traditional electrical steel by a factor of ten in permeability.
on 02015-11-30John Nagle mentions Edison’s “chalk telephone”, which used the #Johnsen-Rahbek effect to directly control friction between a rotating damp chalk cylinder and a wiper. “Silicon carbide was much better than wet chalk, and this effect was used in IBM line printer clutches.” Perhaps this could be used for controlling a 3-D printer. #materials
on 02015-11-26#Craig-Wright explains #mining of graphite in order to make his pencil from scratch. #materials
on 02015-11-26The manufacturer of #Dyneema brand #UHMWPE lists tensile strengths from 2.2GPa (for SK25) up to 3.3–3.9 GPa (for SK78 and SK75), and tensile moduli in the range of 52 to 132 GPa, with a consistent 3–4% elongation at break. Density is .97 to .98 g/cc. #materials
on 02015-11-16This #pdf #paper reports that zinc sulfide #phosphorescent #materials have a bandgap for ultraviolet radiation at 336 nm, and you can excite it with 325-nm light, although its photoluminescence spectrum has a strong peak at 396 nm and a weaker one at 478 nm, leading to the blue-green color we’re familiar with.
on 02015-10-17#pdf compares conventional copper-doped zinc sulfide #phosphorescent #materials to SrAl₂O₄ (under the trade name LumiNova). Zinc sulfide (ZnS:Cu) is said to have about an order of magnitude faster decay, with an “afterglow extinction” of about 200' rather than SrAl₂O₄'s 2000'. There's also a nice log-log graph of the exponential decay, showing a decrease from 200 mcd/m² at 1' to 1 mcd/m² at 50', which gives τ ≈ 9'. SrAl₂O₄’s afterglow lasts much longer not only because it decays more slowly but also because it starts out much brighter. Lots of tips on industrial pigment processing.
on 02015-10-17#pdf #materials #paper on SrAl₂O₄ #phosphorescent pigments, finding that particle size doesn’t affect decay time, which decays from 250 mcd after 1' to 15 mcd after 30' (a factor of 8, so τ ≈ 15') for the bluish-green version, and from 280 mcd after 1' to 15 mcd after 30'. But this is not the standard zinc sulfide phosphor.
on 02015-10-17Interesting, Terfenol-D can reach 2000 microstrains of magnetostriction at saturation. Seems to be what they used for the now defunct SoundBug. #materials
on 02015-09-29Hmm, you can synthesize nitric acid by heating magnesium nitrate (produced, perhaps, by double-exchanging nitrate anions with some other magnesium salt?) and absorbing the resulting nitrogen oxides in water, without using any strong acids. #materials
on 02015-08-30YES, apparently you CAN precipitate #waterglass with magnesium salts. But you get AMORPHOUS magnesium silicate, as a fine powder. #materials
on 02015-08-30"Enstatite", a pyroxene, is yet another magnesium silicate mineral! It’s MgSiO₃, with a 1:1 Mg:Si ratio, in between forsterite’s 2:1 and talc’s 3:4, and it’s not hydrated. It’s around 5-6 Mohs hardness, and forsterite reacts with quartz to form it; apparently it’s possible to hydrate it and turn it into talc. There’s a pyroxene spectrum from enstatite to ferrosilite, FeSiO₃ #materials #minerals
on 02015-08-30No, wait, "forsterite" (an #olivine; Mohs hardness 7! Gemstone peridot!) is magnesium silicate, Mg₂SiO₄. I thought that was talc? Apparently talc is hydrated, so I’m guessing that precipitating #waterglass with magnesium is going to give you something more like talc than like forsterite, which also has a 2:1 Mg:Si ratio, compared to talc’s 3:4 Mg:Si ratio; so baking out the water probably wouldn’t be enough. #Refractory #materials: doesn’t melt until 1900°! (And iron ions, but only iron(II) ions, can replace the magnesium in any concentration.) But wait! There’s #enstatite! #materials #minerals
on 02015-08-30No, wait, "forsterite" (an #olivine; Mohs hardness 7! Gemstone peridot!) is magnesium silicate, Mg₂SiO₄. I thought that was talc? Apparently talc is hydrated, so I’m guessing that precipitating #waterglass with magnesium is going to give you something more like talc than like forsterite, which also has a 2:1 Mg:Si ratio, compared to talc’s 3:4 Mg:Si ratio; so baking out the water probably wouldn’t be enough. #Refractory #materials: doesn’t melt until 1900°! (And iron ions, but only iron(II) ions, can replace the magnesium in any concentration.) But wait! There’s #enstatite! #materials #minerals
on 02015-08-30A #PDF with a bunch of metal #materials #pricing for 1970–2010. Comprehensive, covers nearly all metals and some semimetals. Unfortunately at least some prices use folk units like pounds instead of SI.
on 02015-08-28The USGS gives #pricing information on a variety of mineral #materials, including some historical stuff. #minerals
on 02015-08-28#abstract on tunable-#TCE single-phase #materials made of tin/zirconium manganese oxide, down to zero-TCE.
on 02015-08-16"clearceram-z" is one of the few near-zero #TCE #materials like Sitall, and the curves in this #PDF suggest that that's because it has a local maximum expansion around room temperature, perhaps because it incorporates a negative-TCE phase. Apparently OHARA can’t afford to hire a person literate in English to write their brochure, though.
on 02015-08-16#materials and design techniques for prototypes, by #lcamtuf. A nice table of the crucial strength parameters of common #plastics.
on 02015-08-16reinforcing #plaster #materials (including #slaked-lime plaster) with hair, the traditional material, results in problems if you try wet-store it, because the alkaline plaster eats the hair, a problem that would be even worse with glass fiber. (I think this does not apply to calcium sulfate #gypsum plaster of paris.) Various cellulosic materials have been used, and those resist alkaline environments quite a bit better.
on 02015-08-15#paper on #gelcasting #alumina and zirconia #ceramics #materials with #gelatin and polyethylene spheres to add porosity. Presumably you could use paraffin spheres too, which would be cheaper and maybe improve thixotropy. Something somewhat hydrophilic, not easily water-soluble, and burnable-out might work better still. (Lecithin?)
on 02015-08-15overview of #alginate #materials, especially as used in food
on 02015-08-15this chapter of “Novel Colloidal Forming of Ceramics” discusses #gelcasting #alumina #ceramics by adding hexanedioic acid to dechelate calcium ions from calcium phosphate that had been chelated by sodium hexametaphosphate and trisodium citrate, polymerizing #alginate #materials into a gel. The usual song and dance about ball mills, vacuum degassing, dissolving alginate for days, and so on, but basically their main problem was that it was gelling too damn fast, which is why they came up with this chelation nonsense to slow it down.
on 02015-08-15#Abstract about #Gelcasting 50% (by weight) #alumina #materials with 1% (by weight) #alginate and 1.8% (by volume) calcium phosphate. This seems particularly interesting to me for #3D printing because alginate gels fast when there’s enough ionic calcium present, which can be controlled by temperature.
on 02015-08-15you can use #gelatin for #casting plaster and similar #materials instead of silicone? For some reason the author mixed 2 parts gelatin, 1 part honey, 2 parts glycerin, 1 part water, and for a mold release, cornstarch or talcum powder.
on 02015-08-15this lapsed Japanese patent from 2002 talks about making lime plaster (#slaked-lime) #materials sticky and #thixotropic by using 0.1%–5% #carrageenan (dry weight), which is apparently not as sticky as methylcellulose and won’t crack your plaster by absorbing water later. Some carrageenan molecules (κ and ι) gel with metal ions, while others don’t and are therefore more desirable for this. I'm surprised carrageenan will still gel in the insanely alkaline conditions found in lime plaster. It says you can use up to 4% or 5% (or sometimes as little as 2%) before it starts to shrink and crack as it dries. #patents
on 02015-08-15Galip Sarper Koçlar’s master’s thesis #paper on #gelcasting of #alumina #ceramics #materials with #gelatin and #carrageenan gum. He got best results with 5% by weight gelatin, or 1.7% by weight carrageenan, which resulted in significantly lower fired hardness but higher fired compressive strength than the gelatin, and all his trials were with 47–53% alumina, which reached 95.8% after firing at 1550°, and a bit of Dolapix dispersant. 17.5% linear shrinkage. In English, not Turkish, although it’s kind of broken English. The introduction has the best #survey of gelcasting I’ve found so far. Apparently #acrylamide (and, I guess, other similar binders) needs 30–60 minutes to gel in the mold. He also mentions existing “natural gelcasting” processes for technical ceramics using “starch, ovalbumin, chitosan, alginades [sic; should be #alginate], #gelatin, carragenan [sic] gum and [sic] etc.”, and agarose, with the disadvantage being lower green strength.
on 02015-08-15ORNL developed #gelcasting for “technical” #ceramics #materials (including #silicon-nitride) in the 1980s and 1990s, and this is a #popsci overview; apparently Mark Janney, Stephen Nunn, Claudia Walls, and Ogbemi Omatete are recognized as the inventors. Apparently the advantage over slipcasting is that shrinkage is uniform and the green casting is strong enough to be machinable. Initial experiments used methylcellulose, which gels when heated with water, as the gelifying binder, but “multifunctional acrylate” polymers (??) were the binder that made gelcasting practical, followed by water-based #acrylamide, then less-toxic methacrylamide.
on 02015-08-15discussion of deflocculating #clay #materials by adding acid in order to make them less #thixotropic for #ceramics #slipcasting.
on 02015-08-15getting #ceramics glaze slurry #materials to be #thixotropic typically involves adding a little vinegar or Epsom salt (better for slurries that contain more #clay), but some ceramics processes require deflocculating your glaze slurry or slip to avoid thixotropy. For #slipcasting you normally just partially deflocculate the slip in order to let it remain a bit thixotropic.
on 02015-08-15the #TCE range of different common #materials; e.g. fused silica is 0.55ppm/°, invar is 1.3, #silicon-nitride is 3.2, titanium is 9.5, copper is 16.7, polymers are 50–200, and silicone is 30–300.
on 02015-08-14A #refractory #ceramic (1850° or so), typically sintered with spark plasma sintering. Gelbart’s #steam-engine uses it for the intake valve because it's more resistant to being pitted by the steam than steel is. #materials
on 02015-08-13negative thermal coefficients of expansion (#TCE) in normal temperature ranges are found in and water below 4°, but few other common #materials.
on 02015-08-12