摘要
Abstract
Addressing the risk of tensile tearing failure of laser-welded joints in car seats under collision impact,a refined fi-nite element modeling method is proposed to enhance the accuracy of failure prediction and guide process optimization.Based on the engineering application needs of high-strength steel(DP980/QSTE420TM),the limitations of traditional rigid connection(Rigids)and tied contact(Tied)modeling methods are compared.The node merging connection method is ad-opted,and through mapping mesh division and tolerance control,a one-to-one mapping and fusion of nodes in the welding area is achieved.According to the maximum principal strain failure criterion,the maximum Mises tensile strain is used as an evaluation index.By comparing the material elongation rate,failure judgment standards are established.At the same time,the key modeling parameter of reasonable contact stiffness is studied,suggesting a range between 3～5.Finally,a low-risk laser-welded joint shape scheme is selected.On this basis,the absence of tearing failure in laser welds is verified through high-risk rear impact test conditions,effectively achieving risk prediction of laser welding failure.The research indicates that this model can effectively predict the dynamic failure behavior of laser welding,providing methodological support for the lightweight design of car seats and the simulation of dissimilar material welding.关键词
激光焊/精细化建模方式/失效标准/接触刚度/有限元仿真Key words
laser welding/refined modeling method/failure criteria/contact stiffness/FEM分类
矿业与冶金
