General Knowledge of Silicon Nitride Bonded Silicon Carbide (Si_3N_4-SiC)

Silicon nitride bonded silicon carbide material is a new type of advanced refractory material, and the main products are silicon nitride bonded silicon carbide radiant tubes and silicon nitride bonded silicon carbide bricks.

Properties & Uses

1. Silicon nitride bonded silicon carbide products are hard, with Mohs hardness of about 9, belonging to the hard materials in the non-metallic materials, second only to diamond.

2. Silicon nitride bonded silicon carbide products have high temperature strength. At the high temperature of 1200-1400 ℃, they can remain almost the same strength and hardness as in the room temperature. With the use in different atmospheres, the maximum safe operating temperature can reach 1650-1750 ℃.

3. The thermal expansion coefficient is small. Compared to the products such as silicon carbide, they have high thermal conductivity, not easy for  thermal stress, good thermal shock resistance and long service life. With strong resistance to high-temperature creep, corrosion, extreme coldness and heat, as well as oxidation, they can be easily made into the products meeting the requirements and with high dimensional accuracy.

4. The products are widely used in iron and steel, nonferrous metals, chemicals, building materials and other industries, energy saving, environmentally friendly, and cost reducing.

Development

Silicon nitride bonded silicon carbide is a kind of silicon carbide specialty product widely used in grinding wheels, ceramics, porcelain and other industries by the developed countries such as Norton and Carborundum company in the U.S., Annawevrk and HTK in Germany, TKR and NGK in Japan in the 1970s.