Effect of shot peening intensity on surface integrity of 18CrNiMo7-6 steel

The surface integrity of components treated by shot peening is determined by many influencing factors, which are generally divided into shot peening process parameter, procedure parameter and machine parameter. To understand the influencing relationship of these parameters, and thereby obtain the appropriate peening intensity for the engineering practice, this study experimentally examined the effect of different shot peening parameters on the peening intensity, and further explored the influence of which on surface integrity parameters of carburized steel rollers. It is found that the intensity is mainly affected by the shot diameter (36.73%), air pressure (32.07%) and shot flow rate (23.11%). The maximum compressive residual stress and surface hardness increase linearly as the intensity increases, reaching −1250 MPa and 785 HV at the intensity of 0.55 mmA, respectively. Surface roughness parameter Sq can be used to predict the surface hardness due to the approximately linear relationship between them. • Examined the effect of different shot peening parameters on the peening intensity. • Influence of shot peening intensity on detail evolution of surface integrity is investigated. • Sq can be used to predict the surface hardness after shot peening due to approximately linear relationship between them.