Optimization of Blank Holder Force to Control Wrinkling and Fracture of Cylindrical Cups in Deep Drawing

摘要

The Predominantfailure modes in sheetmetal parts (deep drawingprocess) are wrinkling,fracture. In many cases these defects may be eliminated by appropriate control of the blank holding force (BHF). This papersummarizes the results of a resent study on the formability of rectangularor cylindricalparts fromExtra Deep Draw (EDD) steels. Wrinkling,fracturelimits have been determined and BHF control methods have been developed to eliminate defects, improve part quality, and increase the draw depth.The prediction and prevention of wrinkling and fracture areextremely important in thedesign of tooling and process parameters in deep drawing process. Forming process of Extra Deep Draw (EDD)Steel alloy sheets can be investigated by using deep drawing process. When the BHF is 70-80N/mm2the steel sheets with a thickness 5mm can be produced in the cups without any defects such as wrinkling, tearing.