Numerical Simulation On Fusion Welding Residual Stress In Steel-structure

Welding is widely used in construction, machinery, aerospace navigation and energy engineering. Mostly, residual stresses can induce the failure of the welding structure. Currently, the finite element method is an effectively method which is used in the residual stresses simulation to ensure the welding quality.As yet, many studies have been done in residual stresses, but the study on influence of material physical parameters in steel-structure welding simulation is still rare. Therefore, in this paper, based on the ANSYS software, fusion welding residual stresses are discussed by numerical analysis. In particularly, influences of material physical parameters on steel-structure welding simulation are focused on.Firstly, the basic theories and numerical analysis methods of the welding residual stress field are described in this paper. Secondly, since the thermal and the structure are bilateral coupling, the thermal-structure coupling function of ANSYS software and direct coupling are chosen in the process of numerical calculation. In order to improve the solution accuracy, the paper chooses the birth and death function moving source modal and uses ANSYS APDL language to apply moving heat source load in the process of numerical calculation. The phase transition, which is solved by ANSYS software, is also discussed in this paper. During the simulated calculation, the influences of the specific heat capacity C, the densityρ, and the enthalpy H, which are changed with temperature, are analyzed.The numerical results show that the influences of different physical parameters which are changed with temperature on numerical analysis are not identical. The density and the specific heat capacity have a great influence on the simulation results, but the enthalpy has little impact. Therefore, the enthalpy can be simplified properly. On the different ways of welding, the influences of the same physical parameters which are changed with temperature are not identical. The impact of single-sided welding is less than the double-sided welding. During the study on influence of the enthalpy, with SS316L stainless steel and 20 steel, it is show that the impact of SS316L stainless steel is less than that of 20 steel.