In bearing applications requiring high performance, silicon nitride is considered to have the best combination of mechanical and physical properties. The following are the advantages of silicon nitride ceramics.

Heat resistance

Generally, when the operating temperature of steel bearings exceeds 120°, the hardness will decrease, and the rolling life will also decrease. And silicon nitride has good temperature characteristics, especially suitable for high temperature environment.

Centrifugal force

The density of silicon nitride is about 3.24×103kg/m3, while the density of bearing steel is about 7.8×103kg/m3, which is only about 40% of the density of bearing steel. Therefore, when the bearing is used for the rolling elements, the bearing can suppress the increase of the rolling element load caused by the centrifugal force when the bearing rotates at a high speed.

Linear expansion coefficient

The linear expansion coefficient of silicon nitride is about 1/4 of that of bearing steel, so the dimensional change with temperature changes is small, so it is beneficial to use in environments with large temperature changes.

Hardness, modulus of elasticity, Poisson's ratio

The elastic coefficient of silicon nitride is about 1.5 times that of bearing steel, so the elastic deformation relative to the load is small, and the rigidity relative to the load is high.

Corrosion-resistant, non-magnetic, insulating

When steel bearings are used in machinery used in chemical machinery, food, marine, corrosion is a problem. In a strong magnetic environment, using steel bearings, the fine powder worn from the bearing itself is adsorbed between the rolling elements and the rolling surfaces, which will become the main reason for premature bearing peeling damage and increased noise.