Effects on residual stresses of Ti6Al4V electron beam welding line by laser shock processing

Laser shock processing radiates metals by high power density (GW/cm2), short pulse (ns level) laser beam to produce the high strength impact wave and become residual stress of hundreds MPa. Moreover, Laser shock processing has been shown to harden the surface and improve the mechanical properties of some structural metal components. The surface of Ti6Al4V titanium alloy welding line by electron beam welding (EBW) was processed by repetition-rate Nd: glass laser and repetition-rate Nd: glass laser and mechanical peening. Effects on residual stress of the Ti6Al4V alloy welding line by two technicses have been analyzed. The results are shown that residual stress distributions of the Ti6Al4V alloy welding line by two technicses are clearly improved, and residual stress distributions the latter are more clearly. In particular compressive residual on the subsurface increased with the increase of depth, maximum residual stress appears at the depth of 20-30 μm apart from surface.