Silicon nitride ceramics are a new type of advanced ceramic material made from artificially synthesized high-purity silicon nitride powder under high temperatures and high pressure. It weighs one-third of steel and has a hardness slightly lower than diamond. Compared with other materials, it has many excellent properties such as low density, high strength, good high temperature resistance and corrosion resistance, long service life, self-lubrication, non-magnetic insulation, etc. It is currently the structural ceramic material with the best comprehensive performance and is known as “all-round ceramics”.
Here are some silicon nitride ceramic products:
Silicon nitride ceramic bearings and bearing balls
As an important mechanical basic part, ceramic bearings are highly regarded and applied in the field of new materials because of their better high-temperature resistance and high strength than metal bearings. The materials of ceramic bearings are mainly divided into silicon nitride and zirconium oxide. Compared with zirconium oxide materials, silicon nitride ceramics are suitable for higher speeds, high loads, and high temperature environments. At present, silicon nitride ceramic bearings are mainly used in four aspects: high-speed bearings, high-temperature bearings, vacuum bearings, and corrosion bearings.
Silicon nitride ceramic balls are precision ceramic products sintered at high temperatures in a non-oxidizing environment. They have the characteristics of acid and alkali resistance and corrosion resistance. They can not only be used in seawater for a long time but also have excellent insulation and self-lubricating properties. Therefore, they can be used in environments with high pollution without lubricating media. At 800°C, the strength and hardness of silicon nitride ceramic balls remain almost unchanged, with a density of 3.20g/cm3. The weight is almost 1/3 of the weight of bearing steel, and the centrifugal force is small when rotating. High-speed operation can be achieved.
Silicon nitride turbine rotor
Turbocharging is a technology that uses the exhaust gas generated by the operation of an internal combustion engine to drive an air compressor. Its function is to increase the engine’s intake volume, thereby increasing the engine’s power and torque. At the same time, it is of great significance to reduce fuel consumption, reduce noise, and reduce harmful molecules in exhaust gas. The key part of a turbocharger is the turbine rotor, which is mainly composed of rotor blades, turbine discs, turbine shafts, and other parts. Silicon nitride ceramics have superior properties such as lightweight, high strength, high heat resistance, impact resistance, and high fracture toughness, which are compatible with the requirements of high-quality rotors. Tests have shown that the rotational inertia of turbine rotors made of silicon nitride can be reduced by 40%, the boost response time is 30% faster, and the acceleration at low speeds is significantly improved. In addition, silicon nitride ceramics in turbochargers provides the possibility for lightweight technology on automotive turbochargers.
Silicon nitride ceramic tools
In the context of the decreasing metal mineral resources and rising prices for the preparation of cemented carbide in the world, the development of new technologies has promoted the development of a variety of high-strength, high-hardness, corrosion-resistant, wear-resistant and high-temperature resistant new materials, and ceramic tools have also emerged. Silicon nitride ceramic tools have higher toughness, impact resistance, high-temperature strength and thermal shock resistance than second-generation composite alumina tools. Silicon nitride tools are mainly suitable for rough machining, high-speed cutting, and heavy cutting of cast iron and high-temperature alloys. Their excellent chemical stability and wear resistance can be used for long-term cutting operations under high-speed conditions, and the average operating efficiency is more than three times higher than that of ordinary cemented carbide tools.
Silicon nitride ceramic parts for aluminum metallurgy
The properties of silicon nitride ceramics that resist aluminum liquid corrosion allow them to be used to make thermocouple tube sleeves for temperature measurement, aluminum smelting furnace linings, aluminum liquid bun linings, crucibles, aluminum casting molds, aluminum electrolytic cells and other utensils in aluminum casting and rolling production lines and aluminum smelting and melting operations. For example, thermocouple tube sleeves made of silicon nitride ceramics are used for aluminum liquid temperature measurement. Compared with the commonly used stainless steel and corundum ceramic tube sleeves, this type of tube sleeve has better performance in use. After all, stainless steel is easily corroded by aluminum liquid and will be damaged after 20 hours of continuous use, and corundum cannot withstand thermal shock. Silicon nitride ceramic tube sleeves, which have long-term stable performance in aluminum liquid and do not crack after more than 1,200 intermittent temperature measurements, can be said to be a great tool in the processing process.
In addition, there are nitride ceramic copper-clad substrates, which are used in automotive inverters, reducers, shock absorbers, etc.
Non-Ferrous Crucible Inc. can provide a variety of silicon nitride precision machined parts such as tubes, washers, insulators, rods, flanges, and other high-strength ceramic parts to meet customers’ customized requirements.