Numerical modeling considering initial gradient mechanical properties and experiment verification of residual stress distribution evolution of 12Cr2Ni4A steel generated by ultrasonic surface rolling

Ultrasonic surface rolling process is a promising surface strengthening technique which can improve the fatigue performance of metallic components by introducing reasonably compressive residual stress field. It is of great significance to accurately predict the residual stress distribution of parts in the simulation of ultrasonic surface rolling process. In this paper, a numerical model considering initial gradient mechanical properties (residual stress and micro-hardness) is proposed to predict the residual stress distribution of 12Cr2Ni4A carburized and quenched steel. Moreover, a method is proposed to calculate the ultrasonic surface rolling coverage based on Hertz contact theory, which can guide the optimization of process parameters. The effects of static load, rolling tool radius, amplitude and feed rate on residual stress distribution are investigated. The simulated results and measured results are compared and proved to be in good agreement, which validates the accuracy of the model proposed in this paper.