Effect of hardness distribution in rolling contact fatigue performance of high-speed train axlebox bearings

To investigate the effect of hardness distribution on rolling contact fatigue (RCF) properties of axlebox bearings under deeper carburizing conditions, a two-dimensional finite element model based on continuum damage mechanics was developed. A method combined with an artificial neural network and genetic algorithm was used to search the hardness distribution with the longest RCF lifetime within the process parameters. The results showed that a hardness distribution with high surface hardness and proper carburized case depth had a higher RCF lifetime. The surface hardness of 693 HV and case depth of 1.71 mm were more suitable. It is expected that the results could promote the understanding of the heat-treatment process of carburized bearings and ensure more reliable carburized bearings production.