激光冲击处理1Cr11Ni2W2MoV不锈钢

对1Cr11Ni2W2MoV马氏体不锈钢进行了激光冲击处理(LSP)的基础性研究。激光器最大输出能量为50J,激光功率密度3.7～7.5GW/cm2。吸收层和约束层分别选取Al箔和均匀流水层,激光束采用倾斜入射方式,实验对单光斑试样、搭接光斑试样、疲劳试样分别进行冲击。通过表面形貌、显微硬度和残余应力等检测,验证了激光功率密度对冲击区性能的影响。三组疲劳试件进行对比表明,先冲击后打孔试件的疲劳性能最好,其表面高幅值的残余压应力层能很好地抑制疲劳裂纹的萌生和延长裂纹扩展的速率。实验证明激光冲击处理可以有效提高马氏体不锈钢的疲劳性能。

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.