Determination of the interfacial heat transfer coefficient between AA7075 and different forming tools in hot stamping processes

The interfacial heat transfer coefficient (IHTC) is an important thermo-physical parameter in hot stamping processes, for achieving the desired post-form mechanical strength of formed components. In the present study, the temperature evolutions of specimens under hot stamping conditions were measured using a novel IHTC test facility. The effects of contact pressure and tool material on the IHTC were subsequently investigated between the hot AA7075 specimens and different forming tools. In order to predict the IHTC evolutions, a mechanism based IHTC model was developed to represent the effects of contact pressure and tool material on the IHTC.