不同热输入激光拼焊接头非均匀变形与损伤研究  

Study on non-uniform deformation and damage of laser tailor welded joints with different heat inputs

作　　者：赵琳 石东杰 陈致君 刘高鹏 黄荣学 郭建超 ZHAO Lin;SHI Dong-jie;CHEN Zhi-jun;LIU Gao-peng;HUANG Rong-xue;GUO Jian-chao(College of Mechanical and Control Engineering,Guilin University of Technology at Nanning,Chongzuo 532100,China)

机构地区：[1]桂林理工大学南宁分校机械与控制工程学院,广西崇左532100

出　　处：《塑性工程学报》2024年第5期139-145,共7页Journal of Plasticity Engineering

基　　金：广西科技重大专项(桂科AA22117006);广西壮族自治区中青年教师基础能力提升项目(2023KY0268)。

摘　　要：建立了模拟横向接头拉伸变形的Gurson-Tvergarrd-Neeedleman(GTN)损伤模型,采用有限元反推法确定了接头各分区的损伤参数,对不同热输入激光拼焊接头进行了有限元模拟,分析了其变形与失效行为。结果表明,软化区断裂接头早期应力三轴度较低,随着软化区中部材料发生塑性损伤,后期变形发展快速增加,最终产生软化区断裂模式;当母材区域优先发生塑性损伤后,软化区不再发生变形,最终产生母材断裂失效模式;中热输入横向接头软化区SH22以外其他点孔洞体积分数与高热输入相比有所增加;数值模拟的斜向变形PE 13对应宏观断口的剪切唇区;GTN损伤模型不仅能够反映非均匀接头的变形过程,还能准确反映接头的塑性断裂趋势。The Gurson-Tvergaard-Needleman(GTN)damage model was established to simulate the tensile deformation of transverse joint.The damage parameters of each subarea of joints were determined by the finite element(FE)reverse derivation method.The deformation and failure behavior of laser tailor welded joints with different heat inputs were analyzed by FE simulation.The results show that the stress triaxiality of the fracture joint in the softening zone is low in the early stage.With the plastic damage of the material in the middle of the softening zone,the deformation develops rapidly in the later stage,and the fracture mode in the softening zone is finally generated.When the plastic damage occurs preferentially in the base metal zone,the softening zone no longer deforms,resulting in fracture failure mode in base metal.Compared with the high heat input,the void volume fraction at other points except for softening zone SH22 of the middle heat input transverse joint increases.The numerical simulation of oblique deformation PE 13 corresponds to the shear lip zone of macroscopic fracture.The GTN damage model can not only reflect the deformation process of non-uniform joints,but also accurately reflect the plastic fracture trend of joints.

关 键 词：热输入 GTN损伤模型 应力三轴度 非均匀变形 断裂失效 

分 类 号：TG407[金属学及工艺—焊接]