针对铝合金筒形件传统拉深成形中由于成形性差容易出现拉裂问题,采用拉深预成形和磁脉冲辅助成形相结合的方法对5052-O铝合金板材进行筒形件成形性试验研究,探索磁脉冲辅助冲压成形工艺提高材料成形性的可能性。并研究应用磁脉冲成形减小预成形筒形件圆角半径的工艺可行性。结果表明:与普通冲压相比,磁脉冲辅助冲压成形能够提高材料的成形性,且提高放电电压和增加放电次数能增强圆角的再变形能力,圆角变形更加均匀。普通拉深筒形件减薄最严重部位出现在筒壁和圆角相接处,而磁脉冲辅助冲压成形筒形件有两个减薄严重部位:侧壁与圆角相接处和筒底与圆角相接处。
In view of the crack problems easily occurring in the conventional cylindrical deep drawing process due to the lower formability of aluminum alloy sheet, the method involving pre-forming by conventional deep drawing and re-deformation by electromagnetic forming was designated and performed for experimental investigations on the formability problems of cylindrical parts deformed by 5052-0 aluminum alloy sheet. And the efficacy of enhanced formability for aluminum alloy using this method and the feasibility of decreasing corner radius by electromagnetic forming were discussed. Results show that electromagnetically assisted sheet metal stamping (EMAS) can significantly improve the formability of aluminum alloy sheet compared with conventional stamping process. With the increment of discharge voltage and discharge times, the re-deformation ability of bottom corner of cylindrical part can be remarkably enhanced. The most severe reduction region is existing at the joint of the side wall and bottom corner in conventional deep drawing process, while in EMAS of aluminum alloy cylindrical part, there exist two severe reduction regions: the joint ot7 the side wall and bottom corner and the joint of the bottom and corner region.