Effects of Different R Ratios on Fatigue Crack Growth in Laser Peened Friction Stir Welds
The influence of laser peening on the fatigue crack growth behavior of friction stir welded (FSW) Aluminum Alloy (AA) 7075-T7351 sheets was investigated. The surface modification resulting from the peening process on the fatigue crack growth of FSW was assessed for two different R ratios. The investigation indicated a significant decrease in fatigue crack growth rates resulting from using laser shock peening compared with unpeened, welded and unwelded specimens. The slower fatigue crack growth rate was attributed to the compressive residual stresses induced by the peening.
Changhee Lee, Jong-Bong Lee, Dong-Hwan Park and Suck-Joo Na
O. Hatamleh et al., "Effects of Different R Ratios on Fatigue Crack Growth in Laser Peened Friction Stir Welds", Materials Science Forum, Vols. 580-582, pp. 675-680, 2008