激光冲击强化残余应力的数值模拟研究  

Study on numerical simulation of residual stresses induced by laser shock processing

作　　者：刘子昂[1] 石伟[1] 汪诚[2] 

机构地区：[1]清华大学机械工程系,北京100084 [2]空军工程大学等离子体动力学重点实验室,西安710038

出　　处：《激光技术》2017年第1期1-5,共5页Laser Technology

摘　　要：为了获得激光冲击强化诱导的残余应力场,采用数值模拟的方法,建立了单次激光冲击强化35CD4合金钢厚板2维轴对称有限元模型,对激光冲击过程中材料内部的能量变化、表面动态应力进行了分析,验证了显式动态求解时间选取的合理性,并讨论了模型网格单元尺寸、冲击压力空间分布模型选取对残余应力模拟结果的影响。结果表明,为了得到收敛的模拟结果,选用的网格单元尺寸应为0.03mm左右。单次圆斑激光冲击的残余应力计算结果与已知的实验测量结果吻合得较好。In order to obtain the residual stress field induced by laser shock processing （ LSP ） , the numerical simulation method was used. A 2-D and axisymmetric finite element analysis（FEA）model of single laser shock processing on 35CD4 thick parts was established. History of the energies of material during dynamic analysis and surface dynamic stresses at different times were analyzed to validate the reasonability of the total time of dynamic analysis. The effect of mesh refinement and spatial distribution models of the loading on the simulation results were discussed. The results show that the element length should be around 0. 03mm to get convergent results. The predicted results for single LSP with round laser spot are consistent with the available experimental data.

关 键 词：激光技术 激光冲击强化 数值模拟 残余应力 

分 类 号：TG665[金属学及工艺—金属切削加工及机床]