For the most demanding industrial applications, the performance and operating life of rolling bearings can be optimized by a wide choice of material and heat treatments for rolling bearings. As a significant increase in the rolling bearings demand, it’s common to see bearing application under extreme conditions. It’s become vital that provide a long operating life and optimum performance under conditions as lubricant starvation, highly corrosive and high temperature.
Here is TBB tips to help you selecting material for rolling bearings.
First of all is standard rolling bearing steels. For ordinary industrial applications, standard through hardened rolling bearing steel (100Cr6) is sufficient. Case hardened steel (St4) in rolling bearing quality has good forming characteristics and provides high hardness and wear resistance, as well as good resistance to over-rolling. A slight variation on the above is bainitic hardened 100Cr6 steel. With this material, there is a considerable reduction in the risk of crack formation, even with surface damage. Typical applications for these bearings include wheelset bearings for bucket wheel excavators and trams.
Often bearings manufacturers are required to provide special materials and heat treatments for certain applications or industry sectors. The aerospace sector, for example, specifies M50 steel (martensitic hardened) for many applications such as main shaft bearings and turbine rotor bearings on aircraft engines. This material provides excellent thermal stability (up to 400 deg C) and increased toughness, even at high bearing operating speeds. Offering even higher hardness (up to 70 HRC) are duplex hardened M50NiL steels. These are used if the bearings are subjected to high loads, very high rotational speeds and if a high tolerance to damage is required.