Influence of multiaxial fatigue loading conditions on white etching crack formation

The rolling contact fatigue phenomenon “White Etching Cracks” (WEC) was investigated in this study. The load conditions in a rolling element bearing causing WEC formation were reproduced with a simplified testing setup, using cylindrical specimens and compression-torsion loads. In-phase and out-of-phase loads were tested. It was found that under the same equivalent stresses, the experimental results varied greatly between the two load cycles. Multiple characterisation techniques were used for comparing crack behaviour and microstructural evolution. It was found that only in-phase loading resulted in WEC-like structures. A critical plane approach was employed to find possible reasons for the differing results.