Effect of shot size in surface improvement via shot peening; analytical, modeling and experimental approaches

Abstract

This paper discusses about the surface engineering improvement by means of shot peening. Shot peening improves the surface engineering quality by eliminating the tool marks, such as machining, grinding, stamping and other surface defects. Most importantly, the improvements of shot peening are produced by combination of compressive stress and cold work. Compressive stresses are beneficial in increasing resistances to fatigue failures, while the cold work effects of shot peening treatments can increase the surface hardness. It employs a steel shot media running at high speed to smash the material’s surfaces systematically, which results in a compressed and condensed surface. Several factors influence the effectiveness of shot peening. They are namely shot nature, shot size, shot hardness, Almen intensity, shot angle and coverage. The focus of this research is finding the influence of the shot size. The approaches used are analytical, computational, and experimental studies. The center of the study is the influence of shot size in the generation of the compressive residual stress. Through analytical, computational and experimental approaches, it is confirmed that the shot size has influence on the depth of the peak residual stress rather than the surface residual stress. This research reaffirms the qualitative understanding with quantitative and comprehensive approaches that can also be used for further in depth research in surface engineering improvement especially via shot peening.