Hot compression behaviors and microstructural evolution of high-Mg crossover Al–Mg–Zn based alloys

TY - JOUR

T1 - Hot compression behaviors and microstructural evolution of high-Mg crossover Al–Mg–Zn based alloys

AU - Guo, Chun

AU - Fan, Mengzhuo

AU - Li, Jinyue

AU - Li, Yang

AU - Qian, Feng

AU - Pan, Shiwei

AU - Yan, Hongwei

AU - Li, Xiwu

AU - Cheng, Xingwang

N1 - Publisher Copyright: © 2025 Elsevier B.V.

PY - 2025/7/20

Y1 - 2025/7/20

N2 - Newly developed high-Mg crossover Al–Mg–Zn-based alloys offer low density, excellent mechanical properties and high corrosion resistance. However, as wrought Al alloys, the industrial application of Al–Mg–Zn alloys faces challenges due to their complex hot deformation behaviors, which result from the increased Mg content (∼7%) and the dynamic precipitation of the T- [Figure presented] phase during hot deformation. This work investigates the hot deformation behaviors of a novel high-Mg crossover Al–Mg–Zn based alloy through hot compression tests conducted at different deformation temperatures (320–420 °C) and strain rates (0.001–10 s−1). A constituve model is developed and hot processing maps are established to predict deformation behaviors. Three distinct regions are identified in the processing map: the optimal processing region (360–410 °C/0.001–0.01 s−1) with the highest energy dissipation factor (>55%), the practical processing region (392–420 °C/0.01–0.13 s−1) characterized by moderately high strain rates and the flow instability region (320–420 °C/0.13–10 s−1, 360–385 °C/0.02–0.13 s−1). Microstructural analysis reveals that the dynamic softening mechanisms are primarily governed by dynamic recovery and continuous dynamic recrystallization, with partial discontinuous dynamic recrystallization. Another key finding is the significant role of the T- [Figure presented] phase, which dynamically precipitates during hot deformation. At low strain rates (0.001 s−1), it remains finely dispersed (20.0 ± 2.1 nm), whereas at high strain rates (10 s−1), severe coarsening occurs (244.7 ± 24.7 nm), inhibiting dynamic softening, leading to localized flow instability and reducing hot workability. This study provides insights into the hot deformation mechanisms of high-Mg Al–Mg–Zn based alloys.

AB - Newly developed high-Mg crossover Al–Mg–Zn-based alloys offer low density, excellent mechanical properties and high corrosion resistance. However, as wrought Al alloys, the industrial application of Al–Mg–Zn alloys faces challenges due to their complex hot deformation behaviors, which result from the increased Mg content (∼7%) and the dynamic precipitation of the T- [Figure presented] phase during hot deformation. This work investigates the hot deformation behaviors of a novel high-Mg crossover Al–Mg–Zn based alloy through hot compression tests conducted at different deformation temperatures (320–420 °C) and strain rates (0.001–10 s−1). A constituve model is developed and hot processing maps are established to predict deformation behaviors. Three distinct regions are identified in the processing map: the optimal processing region (360–410 °C/0.001–0.01 s−1) with the highest energy dissipation factor (>55%), the practical processing region (392–420 °C/0.01–0.13 s−1) characterized by moderately high strain rates and the flow instability region (320–420 °C/0.13–10 s−1, 360–385 °C/0.02–0.13 s−1). Microstructural analysis reveals that the dynamic softening mechanisms are primarily governed by dynamic recovery and continuous dynamic recrystallization, with partial discontinuous dynamic recrystallization. Another key finding is the significant role of the T- [Figure presented] phase, which dynamically precipitates during hot deformation. At low strain rates (0.001 s−1), it remains finely dispersed (20.0 ± 2.1 nm), whereas at high strain rates (10 s−1), severe coarsening occurs (244.7 ± 24.7 nm), inhibiting dynamic softening, leading to localized flow instability and reducing hot workability. This study provides insights into the hot deformation mechanisms of high-Mg Al–Mg–Zn based alloys.

KW - Al–Mg–Zn alloy

KW - Constitutive model

KW - Deformation behavior

KW - Hot processing map

KW - Microstructure evolution

UR - https://www.scopus.com/pages/publications/105009696413

U2 - 10.1016/j.jallcom.2025.181741

DO - 10.1016/j.jallcom.2025.181741

M3 - Article

AN - SCOPUS:105009696413

SN - 0925-8388

VL - 1036

JO - Journal of Alloys and Compounds

JF - Journal of Alloys and Compounds

M1 - 181741

ER -