关键词: 成形性能, 电磁成形, 镁合金, 温成形

Abstract: Due to the requirements of energy-saving and environmental protection, lightweight dominates the modern structural design. As the lightest structural metal, magnesium (Mg) is attracting more and more interests from both industrial and academic circles. However, magnesium alloy parts are mainly manufactured by die casting due to the poor sheet formability at room temperature. Warm forming becomes popular since Mg alloy sheets show excellent formability around 200～400 ℃. Electromagnetic forming (EMF) is an effective impact forming process (strain rate >103～104 s–1) without needing lubricant, thus can improve the formability of metal sheets. Warm and electromagnetic hybrid forming (WEMF), is presented to improve the formability of Mg alloy sheet. The effects of voltage, capacity and temperature on the bulging height of Mg alloy sheets are investigated. The results show that the bulging height of sheets increasing with the moderate discharging energy; in order to increase the bulging height, enhancing discharging voltage is more efficient than simply increase the capacity. And if the discharging energy is kept constant, bulging height decreases first (<150 ℃) and then increases (>150 ℃) from 25 ℃ (room temperature) to 230 ℃; the higher the temperature is, the better the formability of Mg alloy will be, but the forming efficiency of WEMF becomes lower.

Key words: Electromagnetic forming, Formability, Magnesium alloy, Warm forming