Analysis And Experimental Research On Large Area Thin-Wall Plate Welding Of Residual Stresses

The welding process is a permanent connection caused by the binding and diffusion between atoms or molecules of two or more materials.As an important technology of steel strcture,which related to the quality of projects and the stability of structure.Because of high centralized instantaneous heat input,a great deal of residual stress and deformation should be brought in the process of the welding,which can influence the capability of welding structure.Therefore it is essential to calculate and analyze the residual stress in welding structure.Based on summing up other's experience,employing numerical calculation method, this paper researcher systemically discusses the ANSYS analytical system of the welding process by realizing the dynamic simulation of welding temperature field and stress field. The best way to reduce the welding residual stress was made, providing the theoretical basis for the promotion of a thin steel plate.The main researches conclusions are listed as follows:(1) The FEA model of thin-wall plate was established.An arrangement method of weld bead element was developed according to the coordinates of weld bead element figure center,with which the element of weld bead were activated step by step to simulate welding desposition process effectively in the welding process.(2) The welding residual stresses and distortions were measured by the hole stress release method.The results show that,vertical deformation plays a dominant role in the welding residual stress,the results and the actual residual stress distributions are consistented.(3) Compared the different welding residual stress,get the best method for theoretical analysis of welding residual stress and provide information of practical value to welding process.(4) This paper researches that how to realize the 3-D dynamic simiation of welding temperature and residual stress field, then uses the research results to simulate the welding process of the welded joints with different plate.The residual stress after welding are predicted.(5) The welding residual stresses and distortions were measured.The distributive patterns of residual stresses and the fitting parameters of actual welding deformation matched well with the results of numerical simulation,which testified the results of the numerical simulation.