i been keeping/collecting used abrasive paper for a while. lately i needed SiC fine powder to mix with fire clay (70%Al2O3 30%SiO2) to increase its
thermal conductivity,since SiC have high value about upward of 200W m−1K−1.since SiC is very hard i can't ball mill it.so i turned to my old
collection of abrasive paper.
some are black and others are not. only black ones are made of SiC. rest are Al2O3.so i cut a sample of black ones and measured it weigh using a
milligram scale .then burned it heating it to red hot to burn off carbon then measured the residue .after some calculation it was 60% SiC.i was so
happy.
i desired 200g of SiC so burned all of my old black abrasive paper.
i washed the SiC and let them dry.used a strainer to get the fine SiC.
the image below is a new abrasive paper and the rest after the straining since i used the good stuff.sorry
hope this helped. thank you.
FYI:you can use SiC and fire clay to make Microwave crucible because SiC absorbs Microwave well.can get up to 1500C if you used proper clay and
insulation.
Boffis - 19-10-2019 at 01:23
Can't you just buy the silicon carbide? I use it for polishing rock slabs and its dirt cheap. You can even buy it ready ground from 32 to 1200 mesh,
its available in 100 to 500g amounts on ebay what more could you want?unionised - 19-10-2019 at 04:35
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