EXPERIMENTAL INVESTIGATION OF A SQUARE-CUP DEEP-DRAWING PROCESS

The analysis of the deep-drawing of a square cup has been carried out as part of an international bench-mark research program organised by t he NUMISHEET organising committee. Aluminum and mild steel have been e mployed in the experiments. The draw-in of the flange has been determi ned for a punch travel equal to 15 and 40 mm. A grid consisting of squ ares was electrochemically etched on the surface of the blanks, and th e principal strains were determined in three directions from grid meas urements for the above-mentioned punch travels. The thickness strains were determined also from direct measurements of the thickness, the th ickness strains so determined comparing favourably with the thickness strains determined from the grid measurements.