Abstract
A deep drawing apparatus, in which piezoelectric actuators are incorporated, is designed and manufactured for ultra thin aluminium alloy sheets. In order to improve limit drawing ratio (LDR), which is the ratio of the maximum diameter of the drawable blank to the punch diameter, actuators are oscillated. By this, cyclic blank-holding pressure is applied to the blank and the blank can be easily drawn without any deffects such as wall breakage and flange wrinkle. (1) LDR is increased from 1.57 to 1.79 with oscillating frequency 200Hz. (2) For reduction in the drawing force, it would be better that the actuators are oscillated throughout the drawing process. (3) Either frequency or amplitude also increases the drawing ratio. (4) It is verified that the oscillation of the actuators contributes to the drastic reduction in coefficient of friction.
