A Method for Improving Fatigue Life of Compressor Blades by Laser Shock Peening and Shot Peening

Taking the TC6 blades as the research object, three kinds of surface strengthening methods were used to improve the surface integrity of the blades, including shot peening (SP), laser shock peening (LSP) and laser shock peening and shot peening (LSP+SP), which fully considered the advantages of LSP and SP. The surface integrity and fatigue life of the blades with different surface states were tested. LSP+SP blades produced the most significant residual compressive stress on the blades surface and had the best fatigue life improvement effect, with the fatigue life increased by 231.8% compared with the as-received blades. After polishing the blades, the fatigue life of LSP+SP blades were further enhanced, reaching 269.9%. The results of sensitivity analysis of surface integrity parameters showed that surface residual stress had the most significant effects on blades fatigue life, which confirmed the superiority of LSP+SP and polishing for improving blades fatigue life.