Laser shock processing on 1Cr11Ni2W2MoV martensite steel

The foundational study of laser shock processing (LSP) for 1Cr11Ni2W2MoV martensite stainless steel is presented in this paper. Capability of the laser system is 50 J per pulse, LSP experiment under water confinement regime perform at laser power density of 3.7-7.5 GW/cm². Aluminum film is used as the absorption layer and restriction layer, and uniform water flow. The laser beam is incidence by oblique way. Different samples are shocked for the following study. The measurement for laser shocked zone include surface profile, micro-hardness and residual stress, and the result confirm that laser power density has influence on the performance of laser shocked zone. Comparing the fatigue result of three types sample, the sample with drilling after shock show the best fatigue performance, because the intense compressive residual stress that around the surface of hole can restrain the initiation of the fatigue crack and retard the propagation of fatigue crack. Laser shock processing is a available method for enhancing the high cycle fatigue of martensite stainless steel via this investigation.