Research On Numerical Simulation For Low Carbon Steel Welding Stracture

With the rapid development of automobile industry, the resistance spot weldingtechnology has been widely used in car body, the quality of spot welding technologydetermines the safety of cars. The number of spots in a car generally up to more than5thousand, and they gurantee the car s safety. Spot welding connection technology iswidely used in auto parts manufacturing, its connection properties will bring animportant effect on later working procedure. Therefore it is a critical issue to do aseries researches on spot welding. In this study, we mainly focus on the research andrealization of low carbon steel structure s spot welding. Finite element analysis (FEA)and experiments were used to study the yield limit and plastic modulus of the plasticring in spot welding structure. The corresponding effect on the whole spot weldingstructure that caused by the yield limit and plastic modulus were also investigated.The main conclusions are as follows:(1) The model of spot welding structure is established and analyzed by FEA. It isfound from the results that the stress concentration area is the plastic ring that on thewelding position. In this region, the normal stress and normal strain in X direction andY direction and the shear stress and shear strain in XY direction are relatively large.The phenomenon reveal that the plastic ring is the structure s weak position, and theresults also reveal that the elastic-plastic strain of the plastic ring has a virtual effecton the whole structure.(2) The angular distortion from the tensile experiment shows the same trend with thatform FEA analysis. The consistency of results illustrates the reasonability of usingFEA to simulate the spot welding structure s areas including nuclear, plastic ring andbase material.(3) The curve of angle deformation with load is gained through the elastic-plasticFEA simulation of the spot welding structure. By compared experiments, the valuesof yield limit and plastic modulus of plastic ring in FEA are adjusted to ensure theconsistency of the angle curves that gained throuth experiment and FEA simulationrespectively. Thereby the FEA parameters of yield limit and plastic modulus are obtained. The researchs can provide a reference for future research.