The effect of short-term heat-treatment on the tribological characteristic of heat-treatable aluminum alloys

In recent years, the interaction of lightweight construction and a decent compromise, between strength and formability, lead to high interest in heat-treatable aluminum alloys of the group 6xxx. An improvement of the formability, due to a local softening, is possible through a partial short-term heat-treatment (SHT) on the semi-finished aluminum material. In order to protect the aluminum surface during transport and to support the tribological conditions at the forming process, a dry lubricant (DL) is often applied to the material. The findings from this research show the enhancement of formability induced by a partial SHT and the simultaneous effect of a decomposed DL by the SHT. Therefore, a deep-drawing tool was used to compare different sheet thickness distributions between the formed parts. For a controlled partial SHT, a contact heating tool was developed, to ensure a homogeneous temperature distribution and short heating time. Furthermore, the increasing friction between blank and tools, caused by the decomposed DL, is demonstrated by using a validated simulation model.