Influence of variable drawbead height and variable contact pressure in Al alloy sheet strip drawing process

Abstract

An electro-hydraulic computer controlled device was created for the realization of the sheet metal strip drawing test. Its main property is realization of contact pressure and drawbead height as different functions dependent on stripe travel or time. In addition, it is also possible to measure drawing force, pressure, drawbead displacement etc. Experimental study of chosen drawbead height and contact pressure functions influence in strip sliding test are presented in this paper. The strips are made of Al alloy sheet metal AlMg4.5Mn0.7 of 0,9 mm thickness. Strip dimensions are 250 x 30 mm. Drawbead geometry, with rounding radii of 2 and 5 mm, is also varied. Drawbead thickness is 10 mm. On contact surfaces mineral oil was applied. The results indicate that acting of combined action of constant pressure with variable drawbead height and constant drawbead height with variable contact pressure, in addition to other conditions, can influence substantially the plastic flow process.