Simulation Analysis And Research On Welding Process Of B-type Aluminum Alloy Metro Traction Buffer Beam

Welding is a very important manufacturing process in today’s society,which is widely used in manufacturing,railway,shipbuilding and other industries.It is an important pillar of national infrastructure construction.However,there will be some welding defects in the welding process,which not only reduces the safety and reliability of the product,but also increases the cost.In view of the effect of residual stress on train performance and quality in subway traction buffer beam welding,this paper analyzes the welding numerical simulation of the traction buffer beam in the base frame of the B-type aluminum alloy subway car based on the software of Simufact.welding.The main contents of this project are as follows:Firstly,in order to solve the problem of large error of shell element simulation results,hexahedral element is used to model the traction buffer beam structure to obtain the finite element model and in order to solve the problem of sudden change of material properties at high temperature,the database of materials needed in the welding process of traction buffer beam was established by the software of JMat Pro.Then,according to the structural characteristics of multi pass welding of traction buffer beam,based on the thermal elastoplastic finite element method,the finite element models of four kinds of welding joints under actual working conditions are created respectively,and the average thermal cycle curve of the four finite element models is extracted to replace the double ellipsoid heat source model.The effectiveness of this behavior can be proved by simulation calculation.Finally,the finite element model is simulated and analyzed by using the software of Simufact.welding,and the welding temperature field and stress field are obtained.In order to find a more excellent welding scheme,orthogonal experiments are designed for different welding sequence and welding process of welding simulation,and the simulation results after welding are cross compared.By comparison,it is found that the welding deformation of the new welding scheme is reduced by 13.1%,and the maximum residual stress is reduced by 6.3%,which meets the target requirements.This study accurately simulates the welding stress changes in the actual production,providing technical support for the welding of metro traction buffer beam.It has important significance for improving the welding quality of metro and has certain guiding significance for the simulation of some large structure weldments.