Study on the effects of material hardening on the development of high-speed rail corrugation

To investigate the effect of material hardening on corrugation development, a theoretical model for corrugation development is proposed, which incorporates the consideration of material properties’ variation. Experiments were conducted to reproduce the corrugation phenomenon, and the mechanical properties of the hardened layer in corrugated rail were obtained utilizing Nano-indentation experiment. The corrugation depth gradually increased and eventually stabilized with the increase of rolling cycles, and the corrugation troughs exhibit greater material hardening compared to the peaks. The numerical algorithm for the corrugation development model was developed and the processes of corrugation development under conditions with and without material hardening were simulated. The growth of corrugation calculated using the model without material hardening exhibits a continual exponential increase with the number of wheel passages, which does not agree with what was observed in experiments and in the field. However, when considering material hardening, the development process of corrugation could be accurately reproduced.