A bearing cage refers to a bearing part that partially wraps all or part of the rolling elements and moves with them to isolate the rolling elements, usually guide the rolling elements and keep them in the bearing.
When the bearing works, the bearing heats up and wears due to sliding friction. Especially under high temperature operating conditions, the action of inertial centrifugal force intensifies the friction, wear and heat. In severe cases, the cage will be burned or broken, resulting in the bearing not working properly. Therefore, in addition to a certain strength, the material of the cage is required to have good thermal conductivity, small friction factor, good wear resistance, strong impact toughness, low density, and a linear expansion coefficient close to that of the rolling element. In addition, the stamping cage needs to withstand more complicated stamping deformation, and the material is also required to have good processing properties. There will be a layer of silver on some extremely demanding cages.
The types of cage materials are: low carbon steel/stainless steel cage, bakelite/plastic (nylon) cage,brass/bronze/aluminum alloy cage, etc.