纳秒脉冲激光诱导冲击波作用下TC17钛合金高应变率本构模型参数辨识  

Parameter Identification of Constitutive Model at High Strain Rate for TC17 Titanium Alloy Under Shock Wave Induced by Nanosecond Pulsed Lasers

作　　者：游熙 聂祥樊[1] 何卫锋[1] 李东霖[1] 

机构地区：[1]空军工程大学等离子体动力学重点实验室,陕西西安710038

出　　处：《中国激光》2016年第8期102-109,共8页Chinese Journal of Lasers

基　　金：国家973计划(2015CB057400);国家自然科学基金(51505496;51305456)

摘　　要：基于Johnson-Cook(J-C)本构模型,提出了基于有限元模型和修正Levenberg-Marquard(L-M)算法的参数辨识方法。对TC17材料进行不同参数、不同工艺的激光冲击,得到了高应变率条件下的残余应力场分布;利用霍普金森压杆得到了中应变率条件下TC17材料的动态响应曲线;将上述两个测试结果作为辨识目标。引入低应变率条件下材料的响应曲线作为约束条件,辨识得到了TC17钛合金高应变率条件下的J-C本构模型参数。实验和计算结果对比验证表明,辨识得到的参数能比较准确地描述TC17钛合金材料高应变率条件下的动态响应规律,并预测激光冲击条件下材料的残余应力场分布。On the basis of the Johnson Cook （J C） constitutive model, one parameter identification method based on the finite element model and the modified Levenberg Marquard （L-M） algorithm is proposed. When TC17 materials are under laser shocking with different parameters and processes, the residual stress field distribution at high strain rate is obtained and the dynamic response curve at intermediate strain rate is obtained by the Hopkinson pressure bar. The above two test results are taken as the targets of identification. The response curve at low strain rate is introduced as a constraint condition and the J-C constitutive model parameters at high strain rate are identified. The comparison between the experimental and calculated results indicates that the parameters obtained by identification can be used to accurately describe the dynamic response law of TC17 titanium alloys at high strain rate and to predict the residual stress field distribution of materials under laser shocking.

关 键 词：激光器 本构模型 纳秒脉冲激光 TC17钛合金 高应变率 参数辨识 

分 类 号：V261.93[航空宇航科学与技术—航空宇航制造工程] TG135[一般工业技术—材料科学与工程]