Effects of aging treatment processes on microstructures and mechanical properties of AZ63 casting magnesium alloy

• Published in: China foundry Vol. 20; no. 4; pp. 307 - 314
• Main Authors: Li, Chun-yu, Wei, Hao-bo, Ruan, Shi-hui, Chen, Jie-yi, Wu, Zong-gang, Yang, Ming-bo
• Format: Journal Article
• Language: English
• Published: Singapore Springer Nature Singapore 01.07.2023; Foundry Journal Agency
• Subjects: Analysis; Engineering; Machines; Magnesium Alloy; Magnesium alloys; Magnesium castings; Manufacturing; Materials Engineering; Mechanical properties; Metallic Materials; Processes; Specialty metals industry; Zinc compounds; A; magnesium alloys; Mg-Al based alloys; AZ63 alloy; aging treatment; heat treatment; TG146.22
• ISSN: 1672-6421; 2365-9459
• DOI: 10.1007/s41230-023-2169-4

The effects of three different aging treatment processes, namely single-stage, double-stage, and reverse double-stage aging treatment processes, on the microstructures and mechanical properties of the AZ63 (Mg-6Al-3Zn-0.25Mn) casting magnesium alloy were investigated and compared. The results indicate that the microstructures of all the aged alloys under the three treatment processes are mainly composed of α-Mg, Mg 17 Al 12 , and Al 4 Mn phases, indicating that the double-stage and reverse double-stage aging treatments have no obvious effect on the type of alloy phases. However, as compared with the single-stage and double-stage processes, the reverse double-stage process has a great effect on the quantity of the Mg 17 Al 12 phases. After the reverse double-stage aging treatment, which results in a stronger drive for decomposition of the supersaturated solid solution, the number of Mg 17 Al 12 phases precipitated in the grains significantly increases. In addition, as compared with the single-stage aged alloy, the tensile properties at room temperature for both the double-stage and reverse double-stage aged alloys are significantly improved. Among them, the reverse double-stage aged alloy achieves the highest tensile strength, yield strength, and elongation of 295 MPa, 167 MPa, and 8.6%, respectively.