Effects of different shot peening parameters on residual stress, surface roughness and cell size

• Published in: Surface & coatings technology 2020-09, Vol.398, p.126054, Article 126054
• Main Authors: Lin, Qinjie, Liu, Huaiju, Zhu, Caichao, Chen, Difa, Zhou, Shuangshuang
• Format: Article
• Language: English
• Subjects: Compressive properties; Constitutive equations; Constitutive relationships; Dislocation cell size; Dislocation density; Mathematical models; Parameters; Residual stress; Shot peening; Surface roughness; Velocity
• ISSN: 0257-8972; 1879-3347
• DOI: 10.1016/j.surfcoat.2020.126054

Shot peening is widely used to strengthen the surface of metal parts, and its effect is affected by various parameters, such as shot peening coverage, peening intensity, peening velocity, shot size and shot material. In this study, a random multi-shots model which incorporated dislocation density-based constitutive equations was established. With the developed model, the effects of peening velocity, peening coverage and double peening on the surface integrity in terms of the residual stress, surface roughness and dislocation cell size were analyzed. The simulated results show that increasing the peening velocity can significantly thicken the refining layer and the compressive residual stress layer (CRSL), and deepen the location of the maximum compressive residual stress (MCRS). Meanwhile, increasing the peening coverage can heighten the magnitude of MCRS in subsurface, but hardly affects the surface compressive residual stress (SCRS) and the thickness of CRSL. Compared to simply pursuing the improved peening velocity and enhanced coverage, the use of an appropriate double peening process can induce a larger SCRS while reduce the surface roughness slightly. •A random multi-shots model is established.•Dislocation density-based constitutive equations are adopted in the model.•Increasing shot velocity can thicken refinement layer and compressive stress layer.•Increasing coverage can heighten the maximum compressive stress in subsurface.•Double shot peening can induce larger surface compressive stress.