Study on non-uniform deformation and damage of laser tailor welded joints with different heat inputs
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 de-formation 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 mid-dle of the softening zone,the deformation develops rapidly in the later stage,and the fracture mode in the softening zone is finally genera-ted.When the plastic damage occurs preferentially in the base metal zone,the softening zone no longer deforms,resulting in fracture fail-ure 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 PE13 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 re-flect the plastic fracture trend of joints.
万方数据
维普
