SIC is widely used in key parts of the steel and non -ferrous smelting industries with its stable high -temperature chemical performance, excellent high temperature strength, high wear resistance and good thermal shock properties, such as blast furnace air, inner walls and ceramic cups, each of each The lining material of the furnace wall and kiln furniture material. Compared with intervertebral and metal compounds, it has higher temperature strength and creep resistance. Compared with oxide ceramics, it has higher thermal conductivity and resistance of heat shock. The high temperature performance of silicon carbide refractory raw material is as follows:
1. High temperature antioxidant performance of SIC refractory material
Although SIC has excellent performance, it is easily oxidized during long -term use. Scholars at home and abroad have studied a lot of research on SIC's oxidation process. The results show that SIC's high temperature oxidation can be divided into two types: inert oxidation and active oxidation. When the O2 division is lower than 10-4Pa, the SIC product is SiO gas phase and the active oxidation of the net weight is reduced; when the O2 section pressure is higher than 10-4Pa, the SIC product is SIO2, the inert oxidation increased by net weight, the SIO2 protective film of the SIO2 protective film Generating can prevent the oxidation from further occurring; but when the oxidation temperature is above 1473K, SiO2 is converted into square quartz at high temperature, which occurs in volume expansion, damage the structure of the oxide film, causes cracks, which will cause oxidation inside the material, which seriously affects the internal oxidation, which seriously affects the internal impact. The service life of silicon carbide material. Therefore, improving the antioxidant performance of SIC materials is a factors that must be considered in designing and preparing silicon carbide refractory materials.
Although silicon carbide refractory raw materials have better antioxidant properties, when oxidation to a certain degree, the damage to the material structure is fatal. Therefore It is of great significance.
2. The anti -heat seismic performance of SIC refractory material
As an important high -temperature industrial structure material, silicon carbide refractory raw materials also have high requirements for its heat shock resistance. The anti -heat seismic properties of SIC materials are not only related to its micro -structure, grain size, and internal defect shape and distribution. It is also related to the strength, elastic modulus, thermal guidance rate, thermal expansion coefficient, pine ratio and the pore rate of the material. Wait for physical properties. Improving and improving the heat seismic performance of SIC materials is of great significance for its safe and stable use.
3. Anti -ice spar erosion performance of SIC refractory material
Because the aluminum liquid is not wet to SIC, and has high thermal conductivity, high chemical stability performance and excellent antioxidant properties, it is used as a groove material for aluminum electrolytic grooves. The smelting of aluminum is generally based on ice spar (NA3ALF6) as a fuse. It is performed by electrolytic aluminum aluminum in electrolytic grooves. The electrolyte temperature is usually 1173 to 1273K. Silicon carbide refractory raw material has a good anti -ice spar erosion performance. From the mechanism of erosion, erosion mainly occurs between the oxide and the oxides binding in the phase of the phase. It can further improve the anti -ice spar erosion performance of silicon carbide refractory material.
