The results show that SiC ceramics with sintered silicon carbide, hot pressing sintering, hot isostatic pressing sintering and reaction bonded silicon carbide ceramic have different properties. For sintered density and flexural strength, SiC ceramics sintered by hot pressing and hot isostatic pressing are relatively more and the reaction bonded SiC is relatively low.
On the other hand, the mechanical properties of SiC ceramics are different from those of sintering additives. SiC ceramics with no pressure sintering, hot pressing and reaction bonded silicon carbide have good resistance to strong acid and strong alkali, but the corrosion resistance of reaction bonded silicon carbide ceramic to super strong acids such as HF is poor. According to the comparison of the high temperature resistance, almost all SiC ceramic strength increased when the temperature was below 900 C, and the flexural strength of the sisic ceramic decreased sharply when the temperature was over 1400 degree. (this is due to a certain amount of free Si in the sintered body for rbsic ceramic, which is caused by a sharp decrease in the bending strength at a certain temperature) .Sintered silicon carbide ceramic and thermal isostatic pressure sintering sic,Its high temperature resistance is mainly affected by the type of additives.