金属热处理 ›› 2021, Vol. 46 ›› Issue (9): 187-192.DOI: 10.13251/j.issn.0254-6051.2021.09.034

• 组织与性能 • 上一篇    下一篇

高合金化Al-9Zn-2Mg-2Cu-0.3Ce合金均匀化过程中的组织演变

张倩1, 史丹丹2, 李彩琼1, 赵志国1,2, 史先利2   

  1. 1.烟台南山学院 工学院, 山东 烟台 265713;
    2.航鑫材料科技有限公司, 山东 烟台 264006
  • 收稿日期:2021-03-24 出版日期:2021-09-25 发布日期:2021-12-09
  • 通讯作者: 赵志国,副教授,E-mail:zhaozhiguohappy@163.com
  • 作者简介:张 倩(1987—),女,副教授,硕士,主要研究方向为材料加工性能与微观组织,E-mail:zqtaian@163.com。
  • 基金资助:
    龙口市科技研发计划(2019KJJH010,2019KJJH021);烟台市校地融合发展项目平台建设类(2020XDRHXMPT18);2020年烟台南山学院青年基金(Q202015)

Microstructure evolution of a high alloying Al-9Zn-2Mg-2Cu-0.3Ce alloy during homogenization

Zhang Qian1, Shi Dandan2, Li Caiqiong1, Zhao Zhiguo1,2, Shi Xianli2   

  1. 1. College of Engineering, Yantai Nanshan University, Yantai Shandong 265713, China;
    2. Hangxin Material Technology Co., Ltd., Yantai Shandong 264006, China
  • Received:2021-03-24 Online:2021-09-25 Published:2021-12-09

摘要: 采用光学显微镜(OM)、扫描电镜(SEM)、电子探针显微分析(EPMA)、X射线衍射(XRD)以及差示扫描量热仪(DSC),研究了一种高合金化Al-9Zn-2.0Mg-2Cu-0.3Ce(质量分数,%)合金的铸态微观组织,以及其均匀化过程中微观组织的演变,获得了较优的单级均匀化工艺。结果表明:铸态时,合金晶粒内部枝晶网络发达,Zn、Mg、Cu元素偏聚严重,合金中主要的非平衡凝固相为T(AlZnMgCu) 相和θ(Al2Cu)相。经过470 ℃×48 h均匀化热处理后,合金中的枝晶网络基本消除,凝固相T逐渐回溶至基体中,主要的残留相为耐高温相Al2CuMg、Al8Cu4Ce和Al7Cu2Fe。扩散动力学分析表明,470 ℃退火48 h的单级均匀化工艺足以使合金中的非平衡相回溶至基体中。

关键词: Al-Zn-Mg-Cu合金, Ce, 均匀化, 微观组织

Abstract: As-cast microstructure and microstructure evolution during homogenization of highly alloying Al-9Zn-2.0Mg-2Cu-0.3Ce alloy were studied by means of optical microscope (OM), scanning electron microscope (SEM), electron probe microanalysis (EPMA), X-ray diffraction (XRD) and differential scanning calorimeter (DSC), and a rather optimal single-stage homogenization process was obtained. The results show that in the as-cast alloy, the dendrite network is well developed with serious segregations of Zn, Mg and Cu, and the main non-equilibrium solidification phases are T(AlZnMgCu) phase and θ(Al2Cu) phase. After homogenization heat treatment at 470 ℃ for 48 h, the dendrite network in the alloy is basically eliminated and the solidification phase T gradually dissolves into the matrix. The main residual phases are high temperature resistant phases Al2CuMg, Al8Cu4Ce and Al7Cu2Fe. Diffusion kinetic analysis shows that the single-stage homogenization process of annealing at 470 ℃ for 48 h is sufficient to make the non-equilibrium phase in the alloy to re-dissolve into the matrix.

Key words: Al-Zn-Mg-Cu alloy, Ce, homogenization, microstructure

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