Deep Drawing Processing of Thick Blank with Bore Expanding.

With a view to regarding deep drawing as a new process for fabricating bottomless tubular elements, a deep drawing test was conducted with thick aluminum material. For the purpose of making the formed cup as high as possible, a combined-type processing of bore expanding and deep drawing was adopted, and the effects of the blank pre-bore diameter on the deep drawability and the formed cup height were investigated by means of an experimental approach. The deep drawability was improved by the combined processing, and the pre-bore diameter had the optimum value for the best deep drawability. Because of the improvement of deep drawability, the combined processing improved the cup height too.