论文部分内容阅读
数值模拟是预测激光冲击残余应力场、研究激光冲击参数对残余应力场影响的一种有效方法。采用显式动力有限元软件ANSYS/LS-DYNA对激光冲击处理(LSP)40Cr钢残余应力场进行三维数值模拟;建立了激光冲击处理40Cr钢残余应力场有限元分析(FEA)模型,实现了激光冲击处理40Cr钢残余应力场的数值模拟;模拟研究了激光功率密度、激光脉冲持续时间、激光光斑尺寸对40Cr钢残余应力场的影响。数值模拟结果表明,残余应力模拟值与实测值之间有着较好的一致性;在激光脉冲持续时间一定的条件下,要想获得最大的表面残余压应力,存在一个最佳的激光功率密度;在激光功率密度一定并且脉宽大于45ns的情况下,表面残余压应力随激光脉冲持续时间的增加而减小;在激光功率密度、激光脉冲持续时间一定的条件下,表面残余压应力随光斑直径增大而增大。
Numerical simulation is to predict the impact of laser shock residual stress field, laser impact parameters of residual stress field is an effective method. The finite element software ANSYS / LS-DYNA was used to carry out three-dimensional numerical simulation of the residual stress field of 40Cr steel by laser shock treatment (LSP). The finite element analysis (FEA) model of residual stress field of 40Cr steel by laser shock treatment was established. Impact simulation of 40Cr steel residual stress field numerical simulation; simulation study of laser power density, laser pulse duration, laser spot size 40Cr steel residual stress field. The results of numerical simulation show that there is a good agreement between the simulated residual stress and the measured value. Under the condition of certain laser pulse duration, the best laser power density exists in order to obtain the maximum residual compressive stress on the surface. Under certain laser power density and pulse width greater than 45ns, the surface residual compressive stress decreases with the increase of laser pulse duration. Under the conditions of laser power density and laser pulse duration, the surface residual compressive stress decreases with spot diameter Increase and increase.