Quantitative analysis of galling in cold forging of a commercial Al-Mg-Si alloy

Abstract

Multiple upsetting-sliding tests are performed at sliding velocities in the range of 20-200 mm.s-1 and at different plastic deformations to reproduce the local contact conditions experienced at the tool/workpiece interface during cold forging of a 6082 aluminium alloy. An original approach, able to evaluate accurately the volume of galled aluminium by means of surface topography acquisitions and energy dispersive spectrometry analyses, is presented. Galling is observed whatever the testing conditions and two types of regimes are underlined according to the sliding velocity. An interesting and strong correlation between the wear volumes and the friction ratio is also highlighted.