Model Building Technique Study Of Weld Residual Stress And Distortion

The un-uniform temperature field during welding caused the residual stress which is the most important factor effect the welded structure and welded assembly performance, so it is very important to get the welding residual stress distribution for designer, maker and user, through know the distribution, designer can do scientific and proper design, also can make use of the distribution to get the prime engineering structure.The welding numerical simulation is using finite element method to calculate the welding process then analysis and evaluation test size, environmental condition, welding parameter overall get the various factors effect the welding residual stress and regulation of distribution.This paper using the FEM software Marc, for the 50 and 60 degree V groove of flat plate butt joint simulate the one-layer and three layers welding, finish each welding and cooling it down to room-temperature then start the next welding true represent process and get the temperature field, residual deformation and welding residual stress, according to the theory analysis and empirical equation verified the temperature field and residual deformation all correct, comparison with experiment verified the welding residual stress regularity and correctly. During welded seam the longitudinal residual stress is stretching stress depart the weld a little express compression stress. Based on the experimental results adjust the factors which effect distribution of the welding residual stress, such as element length, welding speed, heat radius, film boundary condition, get some regularity and supply some reference governing.