Microstructure and Mechanical Properties of a Highly Alloyed Al–Zn–Mg–Cu–Zr Alloy Under T6I4 and T6R6I4 Agings

• Published in: Metals and materials international Vol. 30; no. 4; pp. 857 - 871
• Main Authors: Li, Chen, Wei, Hong-Bo, Xu, Xiao-Jing, Zhou, Qingshan, Han, Meng-Nan, Sha, Shao-Hui
• Format: Journal Article
• Language: English
• Published: Seoul The Korean Institute of Metals and Materials 01.04.2024; Springer Nature B.V; 대한금속·재료학회
• Subjects: Aging (metallurgy); Aluminum base alloys; Characterization and Evaluation of Materials; Chemistry and Materials Science; Copper base alloys; Engineering Thermodynamics; Grain boundaries; Guinier Preston zone; Heat and Mass Transfer; Machines; Magnesium; Magnetic Materials; Magnetism; Manufacturing; Materials Science; Mechanical properties; Metallic Materials; Microstructure; Precipitate free zone; Precipitates; Processes; Solid Mechanics; Tensile strength; Zirconium; 재료공학; Mechanical properties; Aging treatment; Microstructure; Highly alloyed Al–Zn–Mg–Cu alloy
• ISSN: 1598-9623; 2005-4149
• DOI: 10.1007/s12540-023-01556-x

The microstructure and mechanical properties of a highly alloyed aluminum alloy Al-11.3Zn-3.1 Mg-1.6Cu-0.2Zr under four kinds of aging were investigated. The matrix precipitates were featured by η + η ' for T6 and RRA, GP zone for T6I4, and GP zone + η ' for T6R6I4 (T6 + Retrogression + T6I4), respectively. The grain boundary precipitates were featured by continuous GBPs for T6, and discontinuous GBPs for RRA, T6I4, and T6R6I4. The precipitate-free zone width exhibited a decreasing trend from RRA to T6, to T6R6I4, and finally to T6I4. The alloys subjected to T6I4 and T6R6I4 exhibited higher tensile strength and ductility. The precipitate strengthening of the four aged alloys was quantitatively analyzed and discussed in detail. T6I4 and T6R6I4 alloys exhibited a yield strength of 787 MPa and 751 MPa, ultimate tensile strengths of 792 MPa and 778 MPa, and elongation values of 7.8% and 8.3%, respectively. Graphical Abstract