Effects of Sheet Thickness on the Coefficient of Friction Determined by the Draw Bead Simulator (DBS) Test 1999-01-0998
This study addresses the effects of sheet metal thickness on the frictional forces which develop when a strip of sheet metal is pulled through a draw bead configuration. This situation is represented by the draw bead simulator (DBS) test. Sheet steels of various thicknesses in the range 0.5-1.5 mm (0.02-0.06 inches) were used for the analysis. Generally, the coefficient of friction decreases with increasing sheet thickness when the conventional expression for coefficient of friction (μ) is used. A correction factor is proposed which normalizes the μ-value over a range of thicknesses. Also, suggested uses, limitations and improvements for the device are made.