A comprehensive electromagnetic forming approach for large sheet metal forming

By exploiting the potential advantages of electromagnetic forming, a comprehensive approach has been developed for large sheet metal forming. In this study, this approach was applied to form an aluminum alloy sheet into partial-ellipsoid shape. The sheet is with a diameter of 1378 mm, and a thickness of 3.945 mm. Compared to conventional forming process, the forming facility is very light-weight, and has following dimension: a width of 1840 mm, a length of 1840 mm, and a height of 1800 mm. An experiment was performed to evaluate the forming quality obtained by the proposed facility. The profile of the formed sheet was measured and fitting with the die profile to assess the deviation between the formed sheet and the desired shape. About 60% of the sheet area has the deviation with the desired shape less than 1 mm. The thickness was measured to evaluate the thinning of the formed sheet. The maximum thinning over the ellipsoid surface of the formed sheet is only about 9.48%. This study proves the feasibility of the proposed process, which provides a cost-effective method for large sheet metal forming.