Analysis of the Rolling Contact Residual Stresses and Cyclic Plastic Deformation of SAE 52100 Steel Ball Bearings

Abstract

Measurements of the cyclic stress-strain hysteresis loop shapes of hardened, HRC-62, SAE 52100 bearing steel, derived from torsion tests are presented. These are reduced to 3-parameter, elastic-linear-kinematic hardening-plastic (ELKP) representations. The ELKP behavior and properties of the steel are employed in an elastic-plastic finite element model of two dimensional, rolling contact. The distortion of the rim and the distribution and magnitude of the residual stresses and cyclic plasticity for repeated contacts at a Hertzian pressure of p0 = 3636 MPa (528 ksi), are calculated. The results are compared with the residual stresses and other features observed in the inner raceway of SAE 52100 steel, deep grooved ball bearings. The calculations predict the modest residual stresses observed in the early life: N ≲ 106 contacts. The much higher levels of residual stress that develop in later life: 108 ≲ N ≲ 1010 , are shown to be connected with metallurgical changes and an attending volume expansion that are cyclic strain induced. The origins of these stresses and their effect on bearing life are discussed.