抄録
In order to improve the accuracy of both shape and dimension for a cylindrical cup, and reduced the production energy, stretch-draw forming processes were carried out using pure aluminium sheets and pure titanium sheets of 2mm in thickness. The stretch-draw forming processes were carried out by using a blank holder with a stepped holding face. The blank holder consists of four periodical sections to compress the flange of the blank and four stepped sections which are incompressible areas. The shape accuracy for a cylindrical cup is improved by changing the depth of steps of the blank holder and the blank holding force. The optimum conditions in order to improve the shape accuracy for cylindrical cups were also found.
