Effect of wet shot peening on Ti-6Al-4V alloy treated by ceramic beads
(1. School of Materials Science and Engineering, Dalian University of Technology, Dalian 116085, China;
2. Beijing Aeronautical Manufacturing Technology Research Institute, Beijing 100024, China)
2. Beijing Aeronautical Manufacturing Technology Research Institute, Beijing 100024, China)
Abstract: Ti-6Al-4V alloy was processed by wet shot peening with ceramic beads. The effects of the shot peened intensity on the microstructure, surface morphology, and residual stress were investigated. A tensile-tensile fatigue test was performed and the fracture mechanism was proposed. The results demonstrate that the surface roughness after wet shot peening is obviously lower than that after dry shot peening. With the increase of the shot peened intensity, the depth of the residual stress layer increases to 250 μm, and the maximum stress in this layer increases to -895 MPa. The fatigue strength also increases by 12.4% because of the wet shot peening treatment. The dislocation density of the surface layer is significantly enhanced after the wet shot peening with ceramic beads. The microstructure of the surface layer is obviously refined into ultra-fine grains.
Key words: Ti-6Al-4V alloy; wet shot peening; microstructure; residual stress; fatigue property