Original Article

Industrial-scale fabrication and thermal-buffer process optimization of a modified 7xxx aluminum alloy for hot stamping applications

¹ College of Civil Engineering and Architecture, Guangxi Electrical Polytechnic Institute, Nanning 530007, PR China
² Guangxi Key Laboratory of Marine Environmental Science, Guangxi Academy of Marine Sciences, Guangxi Academy of Sciences, Nanning 530007, PR China
³ Guangxi Hongrui Technology Co., Ltd., Baise 533000, PR China
⁴ Nanning Aluminum Fabrication Co., Ltd., Nanning 530031, PR China

^* e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Received: 6 January 2026
Accepted: 29 April 2026

Abstract

Hot-stamped 7xxx aluminum components usually exhibited poor mechanical uniformity due to microstructural inhomogeneity and high quench sensitivity. In this work, an industrially scaled modified alloy was developed by substituting Cr with Zr, increasing Zn/Mg ratio and reducing the contents of Mn, Cu, Fe and Si, combined with three-stages homogenization. This resulted in a homogeneous microstructure and low quench sensitivity. In addition, the thermal-buffer forming temperature of the alloy was determined using DSC analysis, tensile tests, and phase transformation modeling. The results showed that the optimal forming temperature was 500 °C, which preserved solute supersaturation during transfer. After T6 aging, the ultimate tensile strength, yield strength and elongation of the components reached over 540 MPa, 470 MPa, and 14%, respectively. Moreover, the mechanical properties were highly uniform: the hardness variation was within 3 HV, strength dispersion was less than 13.5%, and elongation difference was no more than 1%, satisfying the safety requirements for automotive structural components.