A1100P-O and A1100P-H14 of 0.5, 1.0 and 1.5mm in thickness were punched with the die hole diameters of 10, 15, 20, 25 and 30mm. Cutout is generally completed after two steps of fracture. Cutout is impossible in the following three cases from various die thickness conditions. (1) Td>Dd, (2) Td_??_Dd and (3) Td_??_Dd, where Td is die thickness and Dd is die hole diameter. If Td_??_Dd, the primary fracture does not occur. The length of shear droop in the horizontal orientation on the edges of punched products is nearly equal to the sheet thickness. The ratios of fracture surface to sheet thickness of A1100P-O and A1100P-H14 are from 20 to 30% and from 30 to 40% respectively.
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