Time-variant reliability analysis of angular contact ball bearing considering the coupled effect of rolling contact fatigue damage and wear

Rolling contact fatigue (RCF) damage and wear of angular contact ball bearing (ACBB) are time-varying and coupled, which are competing failure mechanisms affecting each other. Therefore, to more reasonably and accurately evaluate the reliability of ACBB under different number of cycles, a physical model for ACBB reliability analysis considering the coupled effect of RCF damage and wear is proposed. First, the load distribution of ACBB is obtained by performing force analysis on the ball and inner ring separately. The octahedral shear stress, which is the key factor affecting RCF damage, is obtained utilizing Hertzian contact theory. Subsequently, based on damage mechanics theory, a damage evolution equation is applied to describe RCF damage degree. The classical Archard wear model is applied to calculate the wear amount of ACBB. To establish the coupled effect between RCF damage and wear, a geometric constraint equation considering the wear depth of ACBB is proposed. Additionally, to avoid expensive computational effort caused by excessive calls to the performance function, the modified instantaneous response surface (t-IRS) method is used to evaluate the time-varying reliability of ACBB. Eventually, a practical example of ACBB is given to verify the validity and accuracy of the proposed model and method.