Effect of Surface Laser Shock Processing on Ultra-high Cycle Bending Fatigue Properties of Titanium Alloy

Laser shock processing was carried out on TC17 titanium alloy surface, and the residual stress distribution was analyzed. The influences of laser shock processing on ultra-high bending cycle fatigue properties of TC17 titanium alloy were investigated by means of ultra-high bending cycle fatigue tests for specimens before and after strengthening and observation of fracture morphology of fatigue specimens. The result show that the fatigue cracks appeared in the sub surface of TC17 titanium alloy after laser shock processing, which were distributed in the surface and sub surface before laser shock process, and its ultra-high bending cycle fatigue properties doubled after laser shock processing.