Investigation of different lubricant classes for aluminium warm and hot forming based on a strip drawing test. (April 2022) - Schell, L.
Abstract: Over the past 15 years, numerous tribological systems for warm and hot aluminium sheet metal forming have been investigated by various researchers. Two previously disregarded aspects will be examined in this paper with an enhanced strip drawing test: the temperature influence on friction and wear performance in an extensive comparison of different lubricant classes in tool lubrication and the bonding performance of different lubricants to the die surface. In depth analyses of the coefficient of friction (COF) and wear performance (wear-free draw-in) for nine different lubricants and additionally several different formulations / mixtures were carried out for sheet temperatures from 20 °C to 425 °C. Furthermore, approaches for future lubricant developments are given. Highlights: The flat die strip drawing test resolves detailed lubrication effects of temperature supported sheet metal forming. Oil-, wax-, polymer- and solid lubricants show distinct behaviours in temperature supported forming of aluminium sheets. Mixing different lubricant classes can greatly improve overall lubrication performance. Polymer based bonding agents play a key role in solving tribological challenges of tool lubrication.