Effect of die casting temperature on the microstructure and properties of the ZX01 zinc-aluminum alloy

Abstract

This study examines the effect of die casting temperature on the microstructure, mechanical properties, and corrosion resistance of the ZX01 zinc-aluminum alloy. The ZX01 zinc-aluminum alloy samples were produced using different die casting temperatures, and their microstructural characteristics were analyzed using a scanning electron microscope, X-ray diffractometer, transmission electron microscope, and electrochemical workstation. The results demonstrate that as the die casting temperature increases, the volume fraction of the primary η-Zn phase initially decreases. However, it is followed by a gradual increase in the fraction of the η-Zn + α-Al eutectoid structure. The flake spacing distribution of this eutectoid structure also becomes increasingly uniform. In particular, the ZX01 zinc-aluminum alloy die cast at 540 ℃ exhibits a highly uniform size distribution of the primary η-Zn phase, and the η-Zn + α-Al eutectoid structure shows a fine and consistent morphology. The recorded tensile strength, elongation, impact toughness, and hardness of the ZX01 zinc-aluminum alloy are 320.37 MPa, 10.07%, 79.28 J/cm², and 96.56 HV, respectively. Furthermore, the self-corrosion potential and polarization resistance of the ZX01 zinc-aluminum alloy die cast at 540 ℃ were measured at -1.441 V and 593 Ω, respectively. Based on a comprehensive analysis of the microstructure and properties, it can be concluded that the optimal die casting temperature for preparing the ZX01 zinc-aluminum alloy is 540 ℃.