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This work examines the necessary process parameters for die quenching (DQ) during hot stamping and subsequent age hardening and paint bake cycle (PBC) response for two alloys: AA7075 and a developmental 7xxx alloy (referred to as AA7xxx), with a lower Chromium content, higher Zirconium content and higher Zinc-to-Magnesium ratio in comparison to AA7075. For both alloys, a minimum solutionizing time of 8 minutes was found to be required, along with a minimum quench rate of 56°C/s and 27°C/s for AA7075 and AA7xxx, respectively. Two-step aging treatments, leveraging a paint bake cycle (PBC) of 177°C for 30 minutes as the second step, were considered after die quenching and were devised to achieve T6-or T76-level strengths. For AA7075, an aging treatment of 120°C for 8 hours, followed by the paint bake cycle (PBC) produced strength levels similar to a T6 temper. DSC experiments showed that the microstructure from this heat treatment was similar to a peak-aged T6 temper. For AA7xxx, a treatment of 100°C for 4 hours and followed by the paint bake produced a strength similar to a T76 temper, while 120°C for 3 hours followed by the paint bake yielded T6 strength levels. The properties of the custom aging treatments were validated through tensile tests. The resulting stress-strain curves show that it is possible to achieve T6 or T76 properties using a custom aging treatment incorporating the PBC that is 65-83% shorter than standard T6 or T76 treatments.

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