金属热处理 ›› 2024, Vol. 49 ›› Issue (2): 166-171.DOI: 10.13251/j.issn.0254-6051.2024.02.025

• 工艺研究 • 上一篇    下一篇

水热环境下Al-9.2Zn-2.4Mg-1.5Cu铝合金挤压板的固溶时效行为

刘阳1, 亓海全1, 秦翔智2, 韩向楠1, 李天然1   

  1. 1.桂林理工大学 材料科学与工程学院, 广西 桂林 541000;
    2.昆山晶微新材料研究院有限公司, 江苏 昆山 251301
  • 收稿日期:2023-08-13 修回日期:2023-12-11 出版日期:2024-03-27 发布日期:2024-03-27
  • 通讯作者: 亓海全,副教授,硕士生导师,E-mail:alexander_qi@163.com
  • 作者简介:刘 阳(1997—),男,硕士研究生,主要研究方向为金属材料及其热处理工艺,E-mail:1241870284@qq.com。

Solution and aging behavior of Al-9.2Zn-2.4Mg-1.5Cu aluminum alloy extrusion sheet in hydrothermal environment

Liu Yang1, Qi Haiquan1, Qin Xiangzhi2, Han Xiangnan1, Li Tianran1   

  1. 1. School of Materials Science and Engineering, Guilin University of Technology, Guilin Guangxi 541000, China;
    2. Kunshan Jingwei New Material Research Institute Co., Ltd., Kunshan Jiangsu 251301, China
  • Received:2023-08-13 Revised:2023-12-11 Online:2024-03-27 Published:2024-03-27

摘要: 对挤压后的Al-9.2Zn-2.4Mg-1.5Cu合金进行固溶时效处理,其中时效处理在水热环境下完成。采用光学显微镜、扫描电镜、显微硬度计和万能材料试验机等研究了各状态下合金的微观组织和力学性能。结果表明,Al-9.2Zn-2.4Mg-1.5Cu铝合金挤压板经固溶后合金未发生再结晶,晶粒仍呈纤维状,但晶内出现大量亚晶结构,且随着固溶温度的升高,亚晶结构数量也在增加。其次,由于合金Zn含量较高,均匀化后仍残留较多低熔点T相,挤压后低熔点T相沿挤压方向呈链状分布,固溶后部分低熔点T相回溶。当合金固溶温度为475 ℃时,水热环境下随着时效时间的增加,合金的抗拉强度先增加随后减小,水热时效时间10 h时达到峰值,其抗拉强度为733.53 MPa,屈服强度为694.83 MPa,伸长率为13.00%。

关键词: Al-9.2Zn-2.4Mg-1.5Cu铝合金, 固溶时效, 水热环境, 微观组织, 力学性能

Abstract: The Al-9.2Zn-2.4Mg-1.5Cu aluminum alloy after extrusion was solution treated and aged, where the aging was completed in hydrothermal environment. The microstructure and mechanical properties of the alloy were studied by optical microscope, scanning electron microscope, microhardness tester and universal material tester. The results show that there is no recrystallization in the Al-9.2Zn-2.4Mg-1.5Cu aluminum alloy extrusion sheet after solution treatment, and the grains are still fibrous, though in which there are a lot of subgrain structures and the number of subgrains increases with the increase of solution treatment temperature. Secondly, due to the high content of Zn in the alloy, there are still more low-melting point T phase remaining after homogenization. After extrusion, the low-melting point T phase is distributed in chains along the extrusion direction, and part of the low-melting point T phase redissolves after solution treatment. When the solution treatment temperature is 475 ℃, the tensile strength of the alloy increases first and then decreases with the increase of aging time in hydrothermal environment, the hydrothermal aging time for the peak of the alloy is 10 h, the tensile strength is 733.53 MPa, the yield strength is 694.83 MPa, and the elongation is 13.00%.

Key words: Al-9.2Zn-2.4Mg-1.5Cu aluminum alloy, solution treatment and aging, hydrothermal environment, microstructure, mechanical properties

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