Customer requirements of the bearing is good accuracy, good performance, long service life, but the materials used properly or not, not only directly affect the bearing life, and affect the stability of size processing; therefore, the material selection and processing, manufacture of bearings is very important.
The 8.1 rings and rolling body material Material of rolling bearing rings and rolling bodies, each other in the contact area on tiny under a lot of contact stress, the rotational and repeatedly bear the stress. Therefore, the material must have high hardness, resistance to fatigue, abrasion resistance and size stability requirements etc.. In particular, relates to the larger effect of rolling contact fatigue life, such as steel Non metallic inclusions in. In the non metallic inclusions, high hardness of oxide inclusion, vulnerable to fatigue failure of starting point, therefore, the use of non metallic inclusions and less clean steel is necessary.
In general, the rolling bearing rings and rolling bodies, is not only the surface. Its interior also to be hardening, the so-called full hardening, the hardness can reach HRC58 ~ HRC65, the use of materials with high carbon chromium bearing steel. One of the most commonly used for bearing steel second (AfSl-52100; JlS-SUJ2; DlN 100 Cr 6), and the large bearing is bearing steel third (SUJ3), its chemical composition as shown in table 8-1.
8.2 cage material The cage material, must have the ability to live in turning the vibration, shock load intensity, the rolling friction body and a ferrule is small, light weight and can endure bearing operating temperature. Small, medium size bearing on the use of punching cage materials, in addition to using the 0.1% degree of low carbon cold-rolled or hot-rolled steel, as the use of need, use yellow copper or austenitic stainless steel plate.
Some punch holder considered for load change places, but with soft nitriding, the holder by salt bath later increased its impact resistance to.
In addition, the synthetic resin material can emit salty shape is also widely used in cage. The heat resistance of the glass fiber reinforced polyimide (Polyamide) resin. Synthetic resin material holder has the advantages of light weight, corrosion resistance, but also has excellent characteristics of attenuation and lubricating properties, chemical composition of the holder materials.