Interlocking Electrode Resistance Spot Welding Numerical Simulation

Resistance spot welding is one of the most widely used technology in engineering field,which has advantages of low cost,high efficiency and wide application.Based on the research of the traditional resistance spot welding,this paper puts forward a new kind of interlocking connection type electrode resistance spot welding method,combining the resistance spot welding and riveting,melting connection and mechanical interlock phase composite connection mechanism,greatly improve the quality of the welded joint.However,resistance spot welding is a highly nonlinear,multi-factor coupling effect involving thermal power,which is influenced by a large number of random factors.At the same time,the nucleation process of invisibility and instantaneity of spot welding process will be caused great difficulties to the researches on the mechanism of the spot welding,simply by the method of theory or experiment is difficult to the preloading process and mechanism of nucleation process to conduct a comprehensive in-depth study.In this paper,by using ABAQUS finite element analysis software to establish 3 d axisymmetric numerical model,numerical simulation with finite element analysis method of aluminum steel heterogeneous metal interlock type electrode contact resistance spot welding preloading process and electricity and hot melt nuclear forming process are numerically simulated.The welding process mechanism is studied by the distribution state of contact stress and the distribution state of temperature field at each moment of the contact surface during the pre-pressure phase of the simulation results.Firstly,the numerical model is established according to the actual electrode structure,and the necessary pretreatment and the determination of the parameters and contact parameters are carried out.Secondly,numerical simulation analysis is carried out for the pre-pressure contact process of aluminum steel heterogeneous metal interlocking electrode resistance spot welding,and the distribution of stress field at each moment is analyzed to determine the initial conductive area.Then,for aluminum steel heterogeneous metal interlock type electrode resistance spot welding current phase nucleation process numerical simulation analysis,analysis of molten form electric potential distribution and the temperature field distribution in the process of each time,to study the forming law melt nuclear and determine the shape and size of the molten nuclear;Finally,under the condition of the parameters of the numerical simulation of interlock type electrode welding experiment,the experimental results compared with the results of simulation analysis,to determine the reliability of the numerical simulation analysis and errorsource,through the way of combining experiment and simulation to explore the mechanism of welding.The numerical simulation results show that the stress field and temperature field of the interlocking electrode have the characteristics of its structure in comparison with the traditional spot welding.The stress distribution on each contact surface is uneven,and there is obvious stress concentration and stress peak at the edge of the concave electrode.The contact stress peak of the upper electrode and the steel plate is the maximum,the lower electrode and the aluminum plate are second,the contact stress peak between the steel plate and the aluminum plate is the minimum;Steel plate and aluminium plate uniform contact surface area in the center of the welding temperature distribution,temperature on the edge of the interlock type electrode convex parts will appear has skyrocketed and the peak temperature,melt nuclear in convex edge first,as the electricity the extension of time,gradually to the internal diffusion,along the axial and radial growth gradually form the final molten core.Comparing the experimental results with the numerical simulation results,the shape and size of the final fusion core are basically consistent,and the reliability of the numerical simulation results is further verified.This article through to the aluminum steel heterogeneous metal interlock type electrode resistance spot welding numerical simulation,to explore the contact spot welding preloading process and melt welding mechanism of formation of nuclear electricity at the same time for the spot welding quality of real-time control model to provide theoretical basis for the research.