Effects of tool radius on formability during deep drawing of AZ31 magnesium alloy sheets

Abstract

In previous studies, it is known that forming products with practical depth made of AZ31 magnesium alloy sheets can be obtained by applying the warm-deep drawing, where a heated die, blank holder and water-cooled punch are used. However, in‰uence of tool radius, which is one of signiˆcant factors on deep drawing formability, has not been examined systematically under the practical forming speed condition in which hydraulic or mechanical press machine forming are assumed. In this study, we systematically examined eŠects of tool radius and forming speed on the forming limit of warm-deep drawing for the cylinder and square cups. Furthermore, we studied the possibility of the reform of a square cup with small shoulder and corner radii by sizing, as it is di‹cult to form by only deep drawing.

Study of Forming Limit for Rotational Incremental Sheet Forming of Magnesium Alloy Sheet

“…It was revealed that an AZ31 magnesium sheet becomes isotropic and recrystallizes above 200°C. In the case of deep drawing magnesium alloy sheets, the effect of local cooling, [11] the punch radius, [12] tool coating, [13] and blank holding force were also analyzed to assure formability. Due to the difficulty of magnesium sheet forming at room temperature, Won et al [10] and Choo et al [14] studied the formability of magnesium alloy sheets at high temperatures and concluded that a temperature over 200°C was required to achieve the safe forming of magnesium alloy sheets.…”