Research On The Forming Process Of Vehicle Left-right Rear Wheel Cover

The quality of auto-body panel is affected by many factors,like shape and dimension of blank,clearance of punch and mold,holder force,layout of drawbeads,friction coefficient and so on.An inappropriate setting of the process parameters will cause quality defects such as crack,wrinkle,springback and so on,which in turn may affect the performance and the appearance of auto-body panel.Conventional approaches to tackling this problem mainly depend on the experience of designers.The suitable parameters is obtained and modified by tryout and modification.It is hard to obtain the optimum parameters because it has no quantitative analysis for the above-mentioned method.Meanwhile it will prolong the development cycle and increase the cost of production.Optimization of blank shape,dimension and deep drawing process as well as control of springback were performed based on the finite element simulation combined with orthogonal test and optimization algorithm.The deep drawing mold was designed and tested based on the optimized process parameters.Eventually satisfactory drawn parts were obtained,proving the reasonable design of molds and process parameters could be applied to the production.The main research results of this paper are as following.1.According to structure features of the panel of R/L rear wheel of auto-body,the stamping process scheme was designed.It involved in testing of the negative angle and setting of the stamping direction by AUTOFORM software.The die was designed by the principle of binder and addendum.The influences of drawbead parameters on restrict resistance and minimum holder force were investigated.The drawbeads were designed and assigned.2.The drawbeads and the blank were designed by AUTOFORM software.The influences of drawbead parameters on restrict resistance and minimum holder force were investigated.The shape and dimension of the blank was optimized through inverse-forward simulating optimization method of blank shape according to features of structure and contour profile.3.In order to obtain the most important process parameters,the crack and wrinkle were set as optimization objectives.In this paper,the range analyses of the key factors of the deep drawing(holder force,drawbeads resistance and friction coefficient)wereperformed using orthogonal test.Equal diameter test was used to establish the crack index,the quadratic response surface model between the crack index and process parameters,respectively.MATLAB software was used to search the quadratic nonlinear restraint optimization limit value.The appropriate parameters were obtained.4.According to the results of springback analysis,the springback compensation scheme was applied to resolve the big post-drawing springback problem.The springback was controlled under 1.5mm.The deep drawing molds were designed and used in production.