Modeling of drawbead used in sheet metal forming process.

Sheet metal shaping process is the basis of many industrial fields such as electronics, automotive, aviation and space. Together with the industrial developments the requirements of sheet metal parts such as dimensional preciseness, surface quality and shape complexity become more important day by day and they are being researched.Even if the suitable sheet materials fulfilling the required mechanical properties for forming operations are selected, problems are still being faced after forming. Wrinkle, tearing and springback are most well-known defects during sheet metal forming. The reason of these defects is the uncontrolled flow of sheet to the die cavity at an undesired ratio. In order to avoid or minimize the defects that may occur during forming of sheet material, control mechanisms such as blank holder force and drawbead that regulate the material flow are used.In this study, dual phase DP600 steel which is being used more and more in automotive industry in recent years due to high resistance and good formability properties. For the experiments, a hydraulic press with a capacity of 40tons is modernized. By using the obtained data, a mathematical model is developed in order to prediction the drawbead restraining force, radius of drawbead and amount of penetration. The results of the mathematical model and the experiment results are compared and the estimations regarding the drawbead restraining force are found to be in very good accordance with experiment results.