Laser peening and shot peening for titanium alloy blade

Abstract

The characteristic of laser peening (LP) and shot peening (SP) was introduced in this paper, then LP and SP for titanium alloy was studied respectively, including the surface profile and residual stress and fatigue properties. The results show that there was shocked zone with the laser spot size and 10~20 µm depth on the surface of the titanium alloy after LP, the max. residual stress is about −600 MPa, which correspond to the result of SP, but the intensity of plastic deformation was much more than that of SP which only gain depression of 1~2 µm, further more, Suitable laser parameters and overlap rate can gain better roughness of surface. LP was chosen for titanium turbine blade, and there were obvious marks and no cracks on the shock zone of dual beam laser peening.