中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 31 No. 10 October 2021 |
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Nonferrous Metal Materials Science and Engineering of Ministry of Education,
Central South University, Changsha 410083, China）
Abstract:The evolution of microstructure and properties of Al-5.87Zn-2.07Mg-2.42Cu alloys during non-isothermal aging was studied. The mechanical properties of the alloy were tested by stretching at room temperature. The results show that in the non-isothermal aging process, when the alloy is cooled to 140 °C, the ultimate tensile strength of the alloy reaches a maximum value of 582 MPa and the elongation is 11.9%. The microstructure was tested through a transmission electron microscope, and the experimental results show that the GP zones and η'''' phases are the main strengthening precipitates. At the cooling stage, when the temperature dropped to 180 °C, the GP zones were precipitated again. Besides, the experimental results show that the main strengthening phase during non-isothermal aging is η'''' phases.
Key words: Al-Zn-Mg-Cu aluminum alloy; non-isothermal aging; η'' phases; mechanical properties
