Stress And Strain Field Simulation And Deformation Control Of Low Carbon Steel Box

As a reliable,efficient and low cost processing technology in modern manufacturing,welding is widely used in the manufacturing industry.However,the welding residual stress and deformation produced in the welding process is harmful to the performance and service life of the welded workpiece.Therefore,it is of great significance to analyze the residual stress and deformation of the welding.In the welding simulation,the thermal elastoplastic finite element method can simulate the temperature field,the stress field and the deformation of welding workpiece in the welding process and welding cooling stage.However,during the simulation of welding process,thermo elastic plastic finite element method has complex computation process and long computation time,which requires very high workstations and is not suitable for many large structural components.Therefore,the thermal elastoplastic method is simplified in this paper,and a suitable calculation model is put forward to calculate the temperature field and the stress and strain field.In view of the characteristics of box welding,a suitable simulation method is found for calculation and analysis.The specific work is as follows:(1)The string heat source is improved,the segmental heat source model changes with time temperature is established.This model is applied to contrast with the transient moving heat source model for local angle welding model,verifies the consistency of the segmental heat source model calculation results in segments under different situations and transient moving heat source model calculation results the calculated results are verified by experiments.(2)The section model is applied to the body heat source model,analyzed the distribution of temperature and stress in the process of welding and cooling box model,and the welding deformation,and the experiment proves that the application of heat source model in the box calculation model on the feasibility.(3)The temperature field,stress field and welding deformation amount of the box model are analyzed under different welding sequence.The change laws of temperature field,stress field and welding deformation amount under different schemes are compared and analyzed.The research results show that the segmental heat source model can be applied to simulate the welding stress and strain field of low carbon steel box,and it can effectively indicate the welding process and the cooling process after welding.The results of this study can be used to guide the welding process parameters and the selection of welding sequence for low carbon steel box,and it is beneficial to effectively control the welding deformation of the box.