Influence of Shot Peening on Surface Characteristics of Case Hardened SAE9310 Gear Material

Abstract

The shot peening is the cold working process by which the compressive residual stresses are induced in the component, and that increases surface hardness, which can be helpful to avoid the fatigue failure of the component. Shot peening process is using to improve the fatigue life of the automobile and aerospace components. Effectiveness of the shot peening in surface characteristics can be measured by the Almen Intensity, Surface hardness and Surface roughness. The impact of shot peening on case-hardened differential bevel gear is defined in this study. In the shot peening process, the surface of the gear rammed by the small hardened cut wire shots with high velocity and overlapping indentations are created on the gear surface. Hence, thecharacteristics of surface of the gear can be greatly improved by shot peening. For bevel gears, bending fatigue crack is the major failure mode. This study is discussed to enhance the mechanical and surface properties of SAE9310 bevel gear by using the shot peening process. The optimization of shot peening process is done by including multi-performance characteristics i.e. Intensity, Surface hardness and surface roughness of the bevel gear. The analysis includes air pressure, nozzle distance, shot flow rate, exposure time as process parameters. The main objective of this study to decide the optimized shot peening process parameters for required performance characteristics and most influencing factors on surface layer characteristics. The experiments have been conducted using Taguchi’s L9 orthogonal array design techniques.