抄録
A new process for friction aided deep drawing has been developed in which a metal blank holder divided into four segments is used instead of the elastic ring normally employed in punchless drawing. This blank holding device consists of four drawing segments, which can move radially inwards and outwards depending on the blank holding pressure. The drawing process can be efficiently performed using an assistant punch, which partially supports the deformation of the b1ank as well as improving the shape and dimensional accuracy of the drawn cup. The blank is rotated around the punch following every second drawing step to achieve a uniform thickness distribution of the product sidewalls. Deep drawing experiments have been carried out using soft aluminum sheets 0.5 mm in thickness to clarify the details of blank deformation and metal flow in the proposed drawing process. The potential of the proposed process has been confirmed by successfully producing deep cups with a drawing ratio of 4.0.
