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为了研究微尺度下激光冲击过程中冲击波对强化表面塑性变形的影响,进行不同能量和冲击次数下激光微冲击纯铜试样处理,并对冲击试样进行表面形貌测量。结果表明,微尺度下,激光诱导的等离子体冲击波引起的轴向和径向压力同时对冲击表面作用。轴向压力在光斑中心区域附近起主导作用,冲击区域深度方向上塑性变形量随着激光能量和冲击次数的增加而增大;光斑边缘附近,主要受径向压力作用,随着激光能量的增加,径向塑性变形影响区域增大。当激光能量超过70 m J时,单点塑性变形边缘区域明显凸起;径向塑性变形随着冲击次数的增加先增大后减小,冲击次数高于3次时,光斑边缘附近明显凸起。
In order to study the effect of shock wave on the plastic deformation of the strengthened surface during the laser shock process at micro-scale, the laser micro-impacted pure copper sample was treated under different energy and impact times, and the surface morphology of the impact sample was measured. The results show that at the microscale, both axial and radial pressure induced by laser-induced plasma shock waves act on the impinging surface at the same time. The axial pressure plays a leading role in the central region of the spot, and the plastic deformation in the depth direction of the impact zone increases with the increase of the laser energy and the number of impacts. The edge of the spot is mainly affected by the radial pressure. With the increase of the laser energy , The area affected by radial plastic deformation increases. When the laser energy exceeds 70 mJ, the area of single-point plastic deformation is obviously convex. The radial plastic deformation first increases and then decreases with the increase of impact times. When the number of impact is more than 3 times, .