Effect of Combined Forming and Aging Processes on the Mechanical Properties of the Precipitation-Hardenable High-Strength Aluminum Alloys AA6082 and AA7075

Abstract

The recently increasing demand for hot stamped aluminum components in the automotive and aerospace industries explains the necessity of designing efficient and resource-conserving thermo-mechanical processes. Within the thermo-mechanical process, the simultaneous effect of deformation and temperature accelerate the precipitation kinetics. Therefore, this study focuses on the combined effect of forming and aging processes on the mechanical properties of high-strength aluminum alloys AA6082 and AA7075. For this aim, two different thermo-mechanical aging process strategies after solution heat treatment and quenching in a water-dilutable polymer quenchant are proposed. The superpositioning of the forming step is either performed at the beginning or continuously during the aging treatment. The resulting mechanical properties are characterized using tensile tests. With increasing the plastic elongation, there is an increase in yield and tensile strength, which is accompanied by a significant decrease in strain after failure. Both thermo-mechanical aging strategies reveal mechanical properties similar to the conventional T6 peak aged condition with a significant reduction in process time from 24 h to 5 h.