Inside bead forming of aluminum tube by electro-magnetic forming

Abstract In this paper, the inside bead forming of aluminum tube (A6063TD) by electro-magnetic forming (EMF) is reported experimentally and numerically. The shape of the bead was affected by the change of the discharge voltage and the dimensions of a groove at a beading die which have a width and a shoulder radius. With the increase of the discharge voltage and the shoulder radius, the bead height increased due to the increasing of the bending moment. On the discharge voltage of over 4 kV (400 μF), the bead height rapidly increased so that the aluminum tube entered the groove at the beading die from both sides. Therefore the thickness strain at the top of the bead increased, the longitudinal strain of the aluminum tube saturated, and a necking appeared at the bead near the shoulder part of the beading die. Also, the simulation of the bead forming was carried out by using MARC and compared with the experimental results.