Silicon nitride ceramic cylinder liner has better mechanical properties | high compressive strength- Zhejiang Shangguijuli Special Material Technology Co., Ltd.

Silicon nitride has wear resistance and heat resistance and is used as a steam nozzle. It has been running at 800℃ for half a year without obvious damage. Other heat-resistant alloy nozzles can only be used for 1-2 months under the same conditions . In addition, the crushing blades made of silicon nitride are widely used in food processing, which can effectively reduce the contamination of impurities in food. The durability of the blade is also relatively good.

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Characteristics of silicon nitride ceramics

In the Si ₃ N ₄ structure, β-Si ₃ N ₄ has 6 Si atoms and 8 N atoms in one unit cell. Three Si atoms and four N atoms are on the same plane, and the other three Si atoms and four N atoms correspond to the layer β-Si ₃ N ₄ on a higher plane. The unit cell parameters of α-Si ₃ N ₄ do not change much for Si ₃ N ₄ , but they are approximately doubled in the C-axis direction, and they also contain 3% oxygen atoms and many silicon vacancies. Therefore, the stability of the system is poor.

The oxidation resistance temperature of silicon nitride can reach 1400℃, and the use temperature in a reducing atmosphere can reach 1870℃. It is not wet to metals (especially aluminum liquid) and especially non-metals. Silicon nitride ceramics are resistant to chemical corrosion and can stand all inorganic acids and caustic soda solutions less than 30%, as well as many organic acids.

Silicon nitride ceramics can recover transition elements (see transition elements), metal oxides, carbon monoxide, active zinc oxide, and tin dioxide, and release nitrogen oxides and nitrogen dioxide above 600℃.