DIRT-RESISTANT ROLLING ELEMENTS FOR ANTI-FRICTION BEARINGS

摘要

The invention relates to rolling elements for anti-friction bearings consisting of martensitic, fully hardenable steel. According to the invention, the internal pressure stresses at a radial depth of 4 % of the rolling element diameter lie between minus 400MPa and minus 1200 MPa and the hardness or hardness gradient of the finished rolling element has the following characteristics: a) a surface hardness of >=613HV (56 HRc); b) a core hardness of >=285HV (28 HRc); c) a differential (A) between the surface hardness and core hardness >= 150HV (9 HRc); d) the core hardness is achieved at a radial depth of between 8 % and 30 % of the rolling element diameter. This permits a particularly long service life under conditions of mixed friction and dirt retention in the anti-friction bearing.