Experimental study on the mechanism of wheel-rail steels crack initiation and wear growth under rolling contact fatigue

Abstract

A twin-roller fatigue test rig was used to reproduce the process of the coexistence of fatigue crack initiation and wear growth in the specimens from rail specimens. Based on the test rig situation, a prediction model was established according to the prediction method for coexistence of crack initiation and wear growth in rail. Both the results, including wear, crack initiation position and crack length in the specimens by the test and simulation were analyzed for verifying prediction model. The results show that there are many states such as micro-pores and micro-cracks on the contact surface at the same time. The crack initiation position is about 0.031mm from the worn contact surface, which is basically consistent with the experimental observation results. The surface crack length distribution is basically the same, distribution in 0.10~0.35mm. The predicted method of the coexistence of the crack initiation and wear growth is feasible.