Silicon nitride is an inorganic substance with the chemical formula Si3N4. It is an important structural ceramic material with high hardness, inherent lubricity, and wear resistance. It is an atomic crystal; it is resistant to oxidation at high temperatures. Moreover, it can resist the impact of cold and heat. It will not break when heated to over 1000℃ in the air, and then rapidly cooled and heated again. It is precisely because of the excellent characteristics of silicon nitride ceramics that people often use it to manufacture bearings, turbine blades, mechanical seal rings, permanent molds， and other mechanical components. If silicon nitride ceramics, which are resistant to high temperatures and difficult to transfer heat, are used to make the heating surfaces of engine parts, not only can the quality of the diesel engine be improved, fuel savings and thermal efficiency can be improved. China, the United States, Japan. and other countries have developed such diesel engines.
The relative molecular mass of Silicon nitride is 140.28. It is gray, white, or off-white. Silicon nitride is a high-temperature insoluble compound, has no melting point, and has strong resistance to high-temperature creep. The load softening point of reactive sintered silicon nitride without a binder is above 1800°C. Silicon nitride crystals are hexahedral. The density of Si3N4 prepared by the reaction sintering method is 1.8~2.7g/cm3, and the density of Si3N4 prepared by the hot pressing method is 3.12~3.22g/cm3. The Mohs hardness is 9~9.5, the Vickers hardness is about 2200, and the microhardness is 32630MPa. The melting point is 1900°C (under pressure). It usually decomposes at about 1900°C under normal pressure. The specific heat capacity is 0.71J/(g·K). The heat of formation is -751.57kJ/mol. The thermal conductivity is (2-155)W/(m·K). Its linear expansion coefficient is 2.8~3.2×10-6/℃ (20~1000℃). Insoluble in water. He is soluble in hydrofluoric acid. The temperature at which oxidation starts in the air is 1300~1400°C. The specific volume resistance is 1.4×105 ·m at 20°C and 4×108 ·m at 500°C. The modulus of elasticity is 28420~46060MPa. The compressive strength is 490MPa (reaction sintered). Silicon nitride reacts with dicalcium dinitride at 1285°C to form calcium dinitrogen silicide, and at 600°C, it reduces transition metals and releases nitrogen oxides. The bending strength is 147MPa. Silicon nitride can be made by heating silicon powder in nitrogen or reacting silicon halide with ammonia. The resistivity is 10^15-10^16Ω.cm. Silicon nitride can be used as a high-temperature ceramic raw material.
Silicon Nitride applications
Manufacturing structure: such as metallurgy, machinery, aviation, aerospace.
Surface treatment of metals and other materials: such as molds, cutting tools, turbine blades.
Composites: such as metal, ceramic and graphite composite, rubber, plastic
Colorless, transparent self-lubricating wear nanoparticle membrane for mobile phones;
Advanced surface protection such as a car;
Ball valve and part;
Metallurgical, aviation, chemical, energy, and machinery industry make parts such as bead/roller bearings, sleeves, valves, and other wear;
Making cutting tools, molds, cylindrical wall coating, turbine rotors, and blades;
Manufacturing composite materials such as ceramic, graphite, rubber, metal, adhesive, etc.
Nozzle, rocket and missile spray pipe.
Silicon Nitride Supplier
TRUNNANO (aka. Luoyang Tongrun Nano Technology Co. Ltd.) is a trusted global chemical material supplier & manufacturer with over 12 years of experience in providing super high-quality chemicals and Nanomaterials. Currently, our company has successfully developed a series of materials. Silicon Nitride produced by our company is of high purity and good quality. Send us an email or click on the needed products to send an inquiry.