silicon nitride ceramics：
Performance: Inorganic material that does not shrink during sintering, has a small thermal expansion coefficient, and is extremely resistant to high temperatures, and its strength can be maintained to a high temperature of 1200C without falling, excellent thermal shock stability, and amazing chemical corrosion resistance, and can withstand almost all inorganic materials Acid and caustic soda solution below 30% is a high-performance electrical insulating material.
Advantages: It has good resistance to cold and heat shocks. It is heated to more than 1000C in the air, and then rapidly cooled and heated again. It will not be broken. Compared with alumina, it is not easy to transfer heat.
Disadvantages: The coefficient of fracture toughness is low, and the mechanical strength in ceramics is in the low-level, and it is easy to crack and break.
Application: high-temperature bearings, mechanical seal rings, pipes, and valves of electromagnetic pumps for conveying molten aluminum, etc.
Silicon carbide ceramics：
Performance: Excellent mechanical properties at room temperature, high-energy bending strength, excellent oxidation resistance, and good corrosion resistance
Corrosion, high wear resistance, and low friction coefficient, its high-temperature strength can be maintained up to 1600C, it is the best high-temperature strength material among ceramic materials, and its oxidation resistance is also the best among all non-oxide ceramics.
Advantages: Silicon carbide ceramic has excellent high temperature creep resistance, and has semiconductor properties, and the incorporation of a small amount of impurities will cause
It exhibits good electrical conductivity and can be processed to obtain a mirror effect.
Disadvantages: The disadvantage of silicon carbide ceramics is lower fracture toughness, that is, greater brittleness.
Application: Widely used in the lining of large blast furnaces; mechanical seal rings, tools for removing metal burrs, etc.