Blank holder pressure is generally 0.7 to 1.0% of the total sum of the yield and ultimate tensile strength of the sheet metal. Too high a blank holder force (BHF) will cause to tearing of the cup wall. Flange wrinkling will occur if BHF is too low. The relationship between the BHF and the cup heights (CH) is studied in this paper. The effects of sheet properties on the formability of (cold and hot rolled) AA 1017 during cup forming are presented. The results of the study indicate a linear relationship between BHF and CH for thinner gauge hot rolled material (0.7 to 0.9 mm thick). The CH increases slowly as the BHF rises. This could be attributed to substantial recovery obtained during annealing process. However, CH increases significantly with BHF when the material is hot worked prior to annealing.
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