The manufacturing process of silicon carbide

The high-power electric furnace needs to be heated for about 24 hours. After a power failure, the reaction of generating SiC is basically over. After a period of cooling, the side wall can be removed, and then the charge can be taken out gradually.

The furnace charge after high temperature calcination is: unreacted material (for heat preservation in the furnace), silicon oxycarbide (semi-reactive material, the main components are C and SiO), and the binder layer (it is very tightly bonded).

The main component of the material layer is C, SiO2, 40% to 60% SiC, and Fe, Al, Ca, Mg carbonate), amorphous material layer (the main component is 70% to 90% SiC, and it is cubic SiC That is β-sic, the rest are C, SiO2 and carbonates of Fe, Al, Ca, Mg), second grade SiC layer (the main component is 90% to 95% SiC, the layer has formed hexagonal SiC, but the crystal is relatively It is small, very fragile and cannot be used as an abrasive), first-class SiC ((SiC content <96%, and it is hexagonal SiC that is a coarse crystal of SiC), furnace core graphite.