In the late 1970s and early 1980s, China began to develop SIC refractory plate and achieved certain results. Since 1998, our factory has researched and discussed the production process of silicon carbide slabs, and gained certain experience.

1.Raw material selection and processing

Many domestic and foreign manufacturers use black silicon carbide raw materials, which are cheap and have good oxidation resistance. The choice of silicon carbide particle size has a great influence on the oxidation resistance of the product. According to the research of Hunan University, the finer the raw material, the easier it is to be oxidized. The particle size of silicon carbide selected by our factory is as follows:

2.Blank preparation

Since silicon carbide has the disadvantage of being easily oxidized, and considering the ability of the SIC refractory plate to have high thermal stress and bending resistance against thermal gradient, appropriately increasing the critical grain size of the silicon carbide plate can reduce its oxidation rate and improve its thermal stability.

3.Molding

The steel mold semi-dry forming process is applied to the high-tonnage hydraulic press and vibration forming machine, the forming pressure is required to be 600-800kgfcm2. In order to reduce the pressure transmission deviation during the pressing process,use volatile kerosene lubrication molds to reduce friction during molding,the density of the formed embryo body is required to reach 2.6g/cm3, the dimensional error of the product is required to be controlled within ±0.5%, and the flatness is required to be controlled within the range of 0.2-0.5%.