Effects of laser shock peening on corrosion fatigue behavior of 2Crl3 stainless steel

摘要

Effects of laser shock peening (LSP) with different coverage layers on corrosion fatigue (CF) resistance of 2Crl3 stainless steel were investigated by residual stress measuring, corrosion fatigue testing and fatigue fracture morphology observing. The results show that LSP can induce high compressive residual stress on the surface of 2Crl 3 stainless steel, and the value of surface compressive residual stress increases with the increase of LSP coverage layer. The CF life of LSP specimens is much larger than that of as-machined specimens, and it increases with the increase of LSP coverage layers; the CF crack growth rate of LSP specimens decrease compared with that of as-machined specimens, and it decreases with the increase of LSP coverage layers. After the analysis, we can conclude that the fatigue fracture surface of as-machined specimens is flat and contains few secondary cracks. However, for LSP specimens, due to high surface compressive residual stress induced by LSP, the growth of corrosion fatigue crack is effectively restrained, resulting in a river pattern morphology.