Bearing steel performance and requirements
Rolling bearing materials include rolling bearing parts and cages, rivets and other auxiliary materials.
Rolling bearings and their parts are mostly made of steel, and the steel for rolling bearings is usually high carbon chromium steel and carburized steel. With the development of modern science and technology and the increasing use of rolling bearings, the requirements for bearings are becoming higher and higher, such as high precision, long life and high reliability. For some special-purpose bearings, the bearing materials are also required to have high temperature resistance, corrosion resistance, non-magnetic properties, ultra-low temperature, and radiation resistance. In addition, bearing materials include alloy materials, non-ferrous metals and non-metallic materials. In addition, bearings made of ceramic materials are now used in locomotives, automobiles, subways, aerospace, aerospace, chemical and other fields.
The basic requirements for the material of a rolling bearing depend to a large extent on the performance of the bearing. Choosing the right material for the rolling bearing will have a major impact on its performance and longevity. In general, the main failure modes of rolling bearings are fatigue spalling under alternating stress and loss of bearing accuracy due to frictional wear. In addition, there are cracks, indentations, rust and other causes of abnormal damage to the bearing. Therefore, the rolling bearing should have high resistance to plastic deformation, less friction and wear, good rotation accuracy, good dimensional accuracy and stability, and long contact fatigue life. And many of these properties are determined by the combination of materials and heat treatment processes.
Since the basic requirements of the rolling bearing for the material are determined by the failure mode of the bearing, the material required to manufacture the rolling bearing should have the following properties after a certain heat treatment in the post process:
a high contact fatigue strength
Contact fatigue damage is the main form of normal bearing damage. When the rolling bearing is running, the rolling elements roll between the raceways of the bearing and the outer ring, and the contact part is subjected to periodic alternating load, and many of them can reach hundreds of thousands of times per minute. Under the repeated action of periodic alternating stress, the contact surface Fatigue peeling occurs. When the rolling bearing begins to peel off, the bearing vibration and noise increase and the working temperature rises sharply, resulting in the final damage of the bearing. This form of damage is called contact fatigue damage. Therefore, steel for rolling bearings is required to have high contact fatigue strength.
