authoritative explanation of #ceramics sintering and how to handle #zirconia materials in particular (plasticize with 3% Veegum colloidal smectite!)
notes on “metal clay” #materials, which are plasticized sinterable metal particulates
#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”.
you can make terra cotta #ceramics #materials almost as strong as stoneware by adding frit to fill the pore spaces with glass
discussion on #Raspberry-Pi and free software and blobs
Christina B reports success in booting Linux on the #Raspberry-Pi without non-free blobs (rpi-open-firmware); still working on the DMA engine, basic USB stuff, and eMMC reliability.
#Obama commutes #Manning’s sentence; release in May. #USA #politics
Hmm, 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