Enhanced surface properties and contact fatigue performance of Cr4Mo4V bearing steel subjected to ultrasonic surface rolling processing

Abstract The paper presents the experimental studies on the enhanced comprehensive properties of Cr4Mo4V bearing steel using ultrasonic surface rolling process. Considerable improvements in mechanical properties and rolling contact fatigue performance are achieved in the present study, accompanied by the characterization of surface microstructures. The ultrasonic surface rolling process promotes the formation of fine nanocrystalline structures and nano‐sized elongated grains with severe deformation, leading to the increasing residual stress, micro‐hardness and high temperatures hardness. The crack propagation and delamination pit in the surface after ultrasonic surface rolling process is inhibited, further enhancing the rolling contact fatigue life of Cr4Mo4V bearing steel.