Silicon nitride

Chemical properties

slightly beige powder

Physical properties

Gray amorphous powder or crystals. Resistant to thermal shock. Good oxidation resistance up to 1500°C but decomposes into nitrogen and silicon above 1850°C. Excellent corrosion resistance to molten nonferrous metals such as Al, Pb, Zn, Cd, Bi, Rb, and Sn, and molten salts like NaCl-KCl, NaF, and silicate glasses. However, corroded by molten Mg, Ti, V, Cr, Fe, and Co, cryolite, KOH, and Na₂ O.

The Uses of Silicon nitride

Silicon nitride (Si3N4), resistant to oxidation, is an excellent coating for metals, as well as an adhesive and abrasive, and it is used in high-temperature crucibles. It has proven useful as heat-resistant substance for the nozzles on rocket engines.

The Uses of Silicon nitride

As high tempereture engineering material for use in gas turbines, diesel engines.

The Uses of Silicon nitride

Silicon Nitride is used in preparation of thermal conductive Poly(Me Methacrylate)/Silicon Nitride nanocomposites via click chemistry.

General Description

Silicon nitride based ceramics possess high fracture toughness, hardness and wear resistance, resistance to corrosion, thermal stability. Two known polymorphs of silicon nitride exist, alpha and beta Si₃N₄, both have hexagonal structure. A study shows that a third state, cubic spinel structure, has also been synthesized.

Flammability and Explosibility

Non flammable