激光冲击TC4残余应力场的试验及有限元分析  

Experiment and finite element analysis on residual stress field in laser shock processing TC4 titanium alloy

作　　者：张永康[1] 周立春[1] 任旭东[1] 李杨 鲁金忠[1] 

机构地区：[1]江苏大学机械工程学院,江苏镇江212013 [2]江苏财经职业技术学院机电工程系,江苏淮安223001

出　　处：《江苏大学学报（自然科学版）》2009年第1期10-13,18,共5页Journal of Jiangsu University：Natural Science Edition

基　　金：国家自然科学基金资助项目(50735001,50705038);江苏省高校自然科学研究项目(07KJB460012);江苏大学博士创新基金资助项目(CX07B-02X)

摘　　要：为提高钛合金的疲劳强度,采用Nd:Glass强脉冲激光对TC4钛合金表面进行冲击强化处理,采用X射线应力仪对冲击区的残余应力场进行测试,并采用ABAQUS有限元仿真软件对其残余应力场进行分析计算.结果表明,激光冲击使材料表面残留较大幅度的残余压应力,当激光功率密度为3 GW.cm-2时,表面残余压应力值高达400 MPa,残余压应力层的深度约为0.6 mm.有限元分析结果与试验测试值有较好的一致性.不同激光功率密度下残余应力场的有限元分析结果表明,激光功率密度大于1.6 GW.cm-2,冲击区将产生残余压应力,随着功率密度的增加,残余压应力增加并趋于饱和,分析结果可为激光冲击工艺参数的优化提供理论依据.To improve the fatigue strength of TC4, Nd ： Glass pulse laser was used to shock the surface of TC4. X-ray stress analyzer was used to test the residual stress of the shocked area, and calculation was done by finite element software ABAQUS. The results show that there is a large residual stress on the surface of shocked material. When the power density is 3 GW · cm^-2, the amplitude of the residual compressive stress reaches to 400 MPa and the depth of residual stress layer reaches to 0.6 mm. There is good accordance between calculations and experimental tests. The results of finite element analysis with different power density show that when the power density is larger than 1.6 GW · cm^-2, there will be residual stress on the shocked area. As the power density increases, the residual compressive stress will also increase, until saturation. The results can be used as theoretical basis for optimizing the process parameters in laser shock processing.

关 键 词：激光冲击 残余应力 功率密度 钛合金 有限元分析 

分 类 号：TG113[金属学及工艺—物理冶金]