GALLING BEHAVIOR IN SQUARE CUP DRAWING OF HIGH TENSILE STRENGTH STEEL SHEET

A series of experiments have been carried out to investigate the galling behavior in macro-scale in the square cup drawing of a high tensile strength steel sheet. On the die surface, galling occurs at the bottom of the boundary between the straight and corner, and grows upward with the number of drawing cycles. Galling on the drawn cup starts at the top of the same boundary and grows downward with the number of drawing cycles. With decreasing the blank holding pressure or increasing the sliding distance, galling becomes remarked. Galling behavior has been discussed based on the simulation result of FEM.