Laser-shock processing effects on mechanical properties of Ti-6Al-4V alloy

In this paper,laser shock processing technology was employed on Ti6AI4V and the change of mechani- cal properties was investigated.The experiments show that a uniform hardened layer with the thickness of al- most 0.25mm and hardness of 510Hv is obtained on the Ti6Al4V surface when we select proper technologic pa- rameters in laser shock processing.The influence of laser power density on residual stress in the titanium alloy was analyzed and it is found that the higher laser power density,the greater compressive residual stresses at the surface of the sample were obtained.The maximal compressive residual stresses at the surface of the sample is a- bout—264MPa and the distribution of the residual stresses below the surface increased to lmm,which are valu- able effects to aeronautic titanium alloy.With the increase of laser densities,the material tensile strength and hardness in shocked area increase,while the plastic property decreases.