FINITE ELEMENT SIMULATION OF PROCESS AND SPRINGBACK OF FRICTION AIDED DEEP DRAWING USING TAPERED BLANK HOLDER DIVIDED INTO EIGHT SEGMENTS

In this paper, a novel technique on friction aided deep drawing using tapered blank holder divided into eight segments is proposed to overcome defect of friction aided deep drawing using four segments tapered blank holder technique. A taper blank holder is designed to be of two parts: stationary part with 5 degree taper angle and moving parts divided into eight tapered segments. The main function of this tapered blank holder device is adopting the frictional force between the blank and the blank holder segments to work in the useful drawing direction. At first, the drawing mechanism of eight segments tapered blank holder technique and inflow of material in the flange portion of blank are investigated and compared with four segments tapered blank holder technique by ABAQUS software to show the merits of the proposed process. Then, the finite element analysis of springback is investigated by the ABAQUS software. Effect of different process parameters such as initial blank thickness, punch profile radius, blank holder force, friction coefficient and hardening models on springback prediction are studied. A successful deep cup with drawing ratio up to 3.67 can be produced without any defect by using this new technique only in one die set. The cost and time of die fabrication in this technique are less than the conventional deep drawing.