Simulation Of The Influence Of Physical Drawbead On Forming Quality Of High Strength Steel And Optimization Of Its Sturcuture Parameters

The installation of drawbead was one of the most effective means to balance the material flowing in the sheet forming. As the unique rule of high strength steel which was different from ordinary steel in shaping property, it became inaccurate by using the equivalent drawbead to simulate the influence of the drawbead in the numerical simulation. It became feasible by using the physical drawbead in the numerical simulation as the swift development of computer technology. The function of physical drawbead was studied to find its influence on the forming rule of high strength steel. Rules were used to optimize the structure parameters. All above could be used to direct the design of physical drawbead during the forming of high strength steel.The differences of shaping property between high strength steel and ordinary steel were analysed in this paper. To study the influence of physical drawbead in the forming of high strength steel, the parameters related to the size and structure of the drawbead were considered as the research goals. Through the orthogonal experimental design method, a mass of simulation were carried out and the original dates about various parameters influencing the forming of high strength steel were obtained. Combining the analysis results, the influences of various parameters of physical drawbead to the sheet thickness after forming and the springback were provided. Furthermore, the main factors of physical drawbead influencing the forming of high strength steel were obtained. All these conclusions could not only be the guidance in the design of drawbead and be the referenced dates in the modification of drawbead.In order to further study the law of drawbead design, the multivariate nonlinear regression function was used to investigate the effects of the parameters of drawbead on the resistance. The uniformity of the sheet thickness was optimized as the target to solve the problems which existed in the thickness difference and the insufficient deformation of the formed sheet around the corners. Through the simulation it showed that the method of multivariate nonlinear regressing can fit the relationship between the thinning rate of sheet and parameters of drawbead accurately. This method can also set up a restricted mathematical model of forming quality. From the simulation results by comparing before and after the optimization, it came to a conclusion that the method of multivariate nonlinear regressing was feasible. It provided an optimization method for the design of drawbead in actual production.