Forming Process And Parameter Optimization Design Of Clinching Joints For Heterogeneous Plates For Vehicles

The clinching riveting joint technology has the unique advantages of body-in-white connector metal plate parts,and exists in the manufacturing process of various industrial products.The clinching riveting joint technology directly uses the plastic deformation of the plate material to form the mechanical self-locking result of the joint to achieve the purpose of a firm connection.This dissertation focuses on the clinching riveting process of Q235 steel and aluminum alloy 5754 materials commonly used in car bodies,to study the clinching joint process mechanism and related plastic deformation mechanics theory,the influence of mold parameters and the optimization of mold process parameters.The main contents and conclusions of this research are as follows:(1)Theoretical study of clinching riveting and mechanical tensile test of aluminum alloy 5754 sheet.First,Make a corresponding research into the selection of clinching riveting plates and the stress and strain properties of aluminum alloy 5754 and Q235 materials.And briefly analyze the clinching riveting process and related mechanical theory.Preliminary determination of the range of die parameters for the subsequent clinching riveting finite simulation analysis.(2)Finite element simulation analysis of clinching joints process.Establish the clinching riveting joints finite element simulation model of aluminum alloy 5754 and Q235 to simulate the forming process of clinching riveting joint of heterogeneous plates for vehicles by ABAQUS.Analysis of stress-strain distribution and punching load changes during the entire clinching riveting forming simulation process.Then analyze the influence trend of each mold process parameter on the joint feature size.Simulate the mechanical properties of clinching riveted joints in the failure mode.(3)Optimization design of process parameters for clinching riveting die.Orthogonal experimental design of process parameters of clinching riveting dies,and the range analysis and variance analysis of the finite element simulation results,qualitative and quantitative analysis to get the influence law of each die process parameters and joint feature size neck thickness value and embedment value.Established quadratic regression mathematical model as the objective function of the optimization algorithm,the optimal mold process parameter results of each mold process parameter of the joint are obtained based on the objective function optimized by the Pareto solution multi-objective genetic algorithm.(4)Experimental verification of clinching riveting die parameter optimization design scheme.According to the results of the optimal mold process parameters based on the Pareto solution multi-objective genetic algorithm,the mold required for the clinching riveting experiment is designed and processed.Then,Comparison of the neck thickness and embedment of the joint feature size obtained from clinching riveting experiment with the simulation results after optimization.Further,Tensile test of mechanical properties of the joint.The effectiveness of the optimization design is verified by comparing the experimental results of joint mechanical properties with the results of joint mechanical simulation after optimization design...