Effect of Strain Rate and Pulsed Electric Current on the Stretch Formability of AZ31 Sheets: Experimental Analysis Using Erichsen Cupping Test
摘要
In this study, the effects of strain rate and pulsed electric current on the biaxial stretch formability of rolled AZ31 Mg alloy are studied. The objective was to overcome the limited room-temperature formability through electric-assisted forming. Erichsen cupping tests without electric current were performed at displacement rates ranging from 10−4 to 10 mms−1. In electric-assisted tests, a pulsed current is applied (peak current 200–400 A, duty cycle 10–30%) during forming. Erichsen Index (EI) decreased from 3.56 to 2.67 mm as the punch speed increased. At 0.01 mms−1 and 400 A (30% duty cycle), the EI improved by approximately 60% (from 3.11 to 5.01 mm). It was evident that electric-assisted forming provides a highly energy-efficient alternative for Mg sheet forming.