The characteristic of ceramic bearings

● Low density

Due to the low density, ceramic bearings have low centrifugal load, and create little heat so they can work in the conditions of higher speed.

● Suitable elastic ratio

The elastic ratio of ceramics is higher than that of steel, this can increase bearing’s dynamic stiffness, however, the elastic ratio should not be too high, otherwise, excessive elastic ratio will create stress concentration to decrease the bearing capacity.

● Low thermal expansion

This can make bearings insensitive to the changes of temperature, and is helpful to preventing the bearings from being jammed. According to hybrid bearings, the applicable rotation speed interval can be wider.

● High strength

High compressing strength is the requirement of bearing high contact stress (for ceramics, the compression strength are usually determined by the rupture modulus measured by three-point or four-point bending strength )

● High hardness and high toughness

Ceramics have high hardness and high toughness can achieve good surface smoothness, and can prevent the damage of impact and other outer particles.

● Good rolling fatigue performances

This performance is an absolutely necessary for bearings.

● Flaking failure pattern

If the rolling element fails in the working, it should be fatigue flaking, this pattern has sign before bearings being jammed, and is the least harmful failure pattern.

The ceramic bearings working in extreme conditions have some appended performances

● Resistance to elevated temperatures and stability

Ceramic bearings can keep their mechanical stability up to 800℃.

● Corrosion resistance

In the conditions of oxidation and corrosion, especially the contact zone where the oil film have been pushed off due to the repeat rotation, the material should have good oxidation and corrosion resistance.

Now we can produce two kinds of ceramic bearings: ZrO₂ ceramic bearings and Si₃N₄ ceramic bearings.

In the ceramic bearings produce deep ditch ball bearings are the main products, gauge 6000-6008 and 6200-6208, class P0 and P6.