| Drawbead is a important factor in drawing forming of Auto cover panel. Drawbead is able to control the distortion size and distributing of forming area in a relatively large range. It is also able to restrain many defects in drawing process, such as wrinkle, crack and springback. Therefore, In many cases, a successful sheet metal forming process depend on if there is a reasonable designing for drawbead.Thanks to the resource and environmental problem, Automotive circles expend great deal of energy on lightening car's weight saving oil. In order to meet the requests of saving oil, improving security and driving stably at the same time, high strength steel is being widely applied. Compared with ordinary steel, high strength steel have a poor formability, Thus a reasonable design for drawbead if significantly more important.In this paper, first of all, using the method of finite element simulation to study formability law in different drawbead parameters and types of a T-shape part. Author used the finite element simulation software Dynaform to study the formability law of the T-shape part in different drawbead radius, height and types, in order to improve the formability of the T-shape part.Secondly, using the conclusion coming from the studying of the T-shape part into the practical production for car's B pillar part. a target function is founded first as the estimating standard of formability, and then through the method of finite element analysis, compared the formability affected by three different kinds of drawbead types, validated that the Run-out Drawbead is effective to control wrinkle and crack in the B pillar's forming, excelled the other two drawbead types. Base on these, done a further research on formability affected by different open distance in Run-out Drawbead. Obtained the conclusion that it is more propitious to the forming process with a reasonable open distance. Finally, the most reasonable type of drawbead is ascertained, and applied the optimized result to practical manufacturing.In this paper, because of the B pillar part which is hard to be formed has been studied by the method of finite element simulation, so it is possible to forecast the defects in forming process. Therefore, design parameters can be modified timely till find the best one, and the corporation's cost in designing and producing can be reduced significantly. It is a greatly increase for corporation's R & D capabilities and market competitiveness. At the same time, this paper has a certain significance for processes optimizing of similar part in practical producing. |
