Research On Multi-objective Process Optimization And Springback Control Of Automobile Strengthened Panel

As a pillar industry of the country,the rapid development of the automotive industry has prompted the manufacture of automobiles to a higher standard,with safety and light weight issues of particular importance in their manufacture.In this context,higher requirements are placed on the forming quality of cover parts.However,defects such as rupture,wrinkling and springback often occur in the stamping and forming process of high-strength steel.This paper takes the reinforcement plate of a model as the research object,and analyzes the forming and and springback of the parts through the combination of finite element numerical simulation technology and mathematical optimization to solve the defects generated in the forming process of the parts.The process analysis and the corresponding process design were carried out for the forming characteristics of the reinforcement plate,and the stamping and forming simulation analysis was carried out by DYNAFORM software.The results show that the forming effect is better with the setting of extension bars and the trimming analysis and springback analysis are done on the basis of this forming.For the problem of forming defects arising from the reinforcement plate,this paper uses the response surface method based on numerical simulation technology to optimize the maximum thinning rate and maximum springback of the part as the final optimized target quantity,and the four process parameters,namely crimping force,friction coefficient,resistance coefficient of the stretching bar,and die closing gap of the concave and convex die,as the optimized variables,and a 4-factor,3-level BBD test is designed using the software.A multi-objective response model was established and tested and the effect law of single variable and bivariate on the target quantity was analyzed.The response surface model was solved using Design-expert 13.0software to obtain the optimal combination of process parameters after optimization.DYNAFORM software was applied to import and numerically simulate this combination of process parameters,and the maximum thinning rate of 23.984% and the maximum springback of 7.829 mm were obtained for the reinforced plate part.The optimized amount of springback still did not meet the assembly requirements and further control of springback was required.The springback compensation module of the simulation software was used to control the springback of the mold profile.After three iterations,the springback of the part is less than 2 mm,which basically meets the requirements.After applying the compensated mold and the optimized process parameters to the simulation analysis,the thinning rates of the simulated part and the real part were 23.516% and 23.31%,respectively.The thickness and thinning rate of the simulated part and the real part were compared at the same position,and the thickness and thinning rate of the real part were similar to those of the simulated part,which verified the accuracy of the optimization scheme and was of great significance for the subsequent production processing.