Investigation into the effect of Clearance-thickness Rratio (RC) on the hole-flanging produced by punch in AA5754-H22 Aluminum alloy Sheet

The hole-flanging process is one of the metal forming processes. In this research, hole-flanging was done on AA5754-H22 aluminum alloy sheet with the initial hole of 30 mm aimed to achieve a flanged hole with 45 mm in diameter with RC equal to 1.3, 1, 0.7, and 0.4. The results showed that the best ratio for hole-flanging in the ironing range is Rc =0.7 and in the bending range is Rc=1. Due to the ironing operation, the more height can be achieved in Rc =0.7. The maximum achievable height between the produced flanges is related to the one produced in Rc =0.7 with an initial hole of 30 mm which has reached a height of 6.8 mm with a hole expansion ratio equal to 1.5. The results from the hole-flanging were such that, reducing RC requires more force for flanging.

Keywords:

Hole-flanging , clearance-thickness ratio (Rc) , AA5754-H22 aluminum alloy sheet , force–displacement diagram