基于霍普金森拉杆试验的焊点焊核区动态本构关系确立  

Dynamic Constitutive Relationship in Spot Welding Area Based on Hopkinson Bar Test

作　　者：吴鑫[1] 钟原[2] 宋力[1] 

机构地区：[1]宁波大学机械工程与力学学院,浙江宁波315211 [2]中国汽车技术研究中心,天津300300

出　　处：《宁波大学学报（理工版）》2015年第4期129-132,共4页Journal of Ningbo University：Natural Science and Engineering Edition

基　　金：国家自然科学基金(60874083)

摘　　要：以DC53DZ为基板,进行焊点结构的焊核区力学特性研究.通过设计试验试件并利用MTS静态拉伸机及霍普金森拉杆（Split Hopkinson Tension Bar,SHTB）对其进行准静态拉伸及应变率600~1 600 S-1之间的动态拉伸试验,得到焊核区的力学特性,并确立了其基于CowperSymonds本构方程参数.利用数值仿真对焊核动态拉伸试验进行模拟,验证了设计试件的长宽比能使试件满足试验要求的轴向应力应变均匀状态.最后由模型中得到的焊核区应力-应变曲线与试验数据拟合,再现了焊核区材料特性试验曲线.验证了DC53DZ钢板的焊点焊核的本构方程参数的合理性.The mechanical characteristics of nugget zone of spot welding based on steel DC53DZ is investigated. The test using MTS quasi static tensile test is conducted. Dynamic tensile test with the strain rate between 600-1 600 S-t is carried out by applying Split Hopkinson Tension Bar （SHTP） to obtain the constitutive parameters of Cowper-Symonds model. Numerical simulation is carried out using LS-DYNA, and the result shows that both the stress and strain are uniformed within the specimen under the designed ratio of length-to-width. With the constitutive parameters obtained from the experiment, the simulated dynamic tensile test is in good agreement with the real-world test, indicating the validity of the dynamic tensile test in this paper.

关 键 词：霍普金森拉杆 车身焊点 焊核 Cowper-Symonds本构方程 

分 类 号：O341[理学—固体力学]