Ceramic Materials Used In Bearing Manufacturing Industry —Silicon Nitride Materials

Silicon nitride ceramic bearings are mainly used in four aspects:
1.High-speed bearings;
2.High-temperature bearings;
3.Vacuum bearings;
4.Corrosion bearings.
The reason why silicon nitride ceramic ball bearings can work in special environments and conditions is entirely due to the performance of silicon nitride ceramics. Silicon nitride ceramics make ceramic bearings have the following advantages:
1. High speed
The weight of the ceramic material is only 40% of the weight of the same steel material, and its low density can realize the light weight and high speed of the bearing, so that the ceramic bearing can suppress the increase of the rolling element load and slip caused by the centrifugal force when the ceramic bearing rotates at high speed , the speed of ceramic bearings is 1.3 to 1.5 times that of steel bearings, and its DN value can reach 3 million.
2. High rigidity
The elastic modulus of silicon nitride ceramics is much higher than that of metal, which is 1.5 times that of metal, so the elastic deformation after stress is small, and the rigidity relative to the load is high, which can increase the rigidity by about 15% to 20%, thus reducing the machine tool.
3. Long – life service
In addition, the mechanical strength of silicon nitride ceramics is not low, and its tensile strength and flexural strength are equivalent to those of metals; while its compressive strength is extremely high, about 5 to 7 times that of metal materials, especially under high temperature conditions, still It can maintain high strength and hardness, and the strength remains basically unchanged even at 1200°C. In the case of foreign matter mixed in, ceramic balls rarely cause spalling failure. Therefore, ceramic bearings with good indentation resistance usually have a longer The service life of steel bearings is generally 3 to 5 times higher than that of steel bearings.
4. Low heat radiation
Since the friction coefficient of silicon nitride ceramic materials is small, which is about 30% of standard bearing steel, compared with metal materials, silicon nitride ceramics have poor thermal conductivity, so the heat generated by ceramic bearings is small during operation, which can be used Extends the life of the grease.