金属热处理 ›› 2020, Vol. 45 ›› Issue (3): 231-234.DOI: 10.13251/j.issn.0254-6051.2020.03.046

• 测试与分析 • 上一篇    下一篇

不同应变速率下5B70铝合金的拉伸断口分析

周巍1, 姜锋1,2,3, 赖松柏4, 方杰4, 童蒙蒙3   

  1. 1. 中南大学 轻合金研究院, 湖南 长沙 410083;
    2. 轻质高强结构材料重点实验室, 湖南 长沙 410083;
    3. 中南大学 材料科学与工程学院, 湖南 长沙 410083;
    4. 中国空间技术研究院 载人航天总部, 北京 100094
  • 收稿日期:2019-09-13 出版日期:2020-03-25 发布日期:2020-04-03
  • 通讯作者: 姜 锋,教授,博士,主要从事高性能有色金属新材料(铝钪合金、铜铬锆合金、铁基合金等)研究,E-mail:jfeng@csu.edu.cn
  • 作者简介:周 巍(1993—),男,硕士研究生,主要从事5B70铝合金研究,E-mail:jfeng2@csu.edu.cn。

Tensile fracture analysis of 5B70 aluminum alloy under different strain rates

Zhou Wei1, Jiang Feng1,2,3, Lai Songbai4, Fang Jie4, Tong Mengmeng3   

  1. 1. Light Alloy Research Institute, Central South University, Changsha Hunan 410083, China;
    2. Science and Technology on High Strength Structural Materials Laboratory, Changsha Hunan 410083, China;
    3. School of Materials Science and Engineering, Central South University, Changsha Hunan 410083, China;
    4. Beijing Institute of Manned Space System Engineering, China Academy of Space Technology, Beijing 100094, China
  • Received:2019-09-13 Online:2020-03-25 Published:2020-04-03

摘要:

研究了不同应变速率下5B70铝合金的拉伸断口。结果表明:随着应变速率的增加,合金的断后伸长率下降。断口分析表明,应变速率越低,断口中的韧窝数量多且深度深,表现出明显的高韧性断裂。随着应变速率的增加,出现准解理面,合金偏向于脆性断裂。随着应变速率的增加,合金断口侧面晶粒伸长减小,析出相的数量减少。

关键词: 5B70铝合金, 应变速率, 显微组织, 准解理断裂, 断口分析

Abstract:

Tensile fractures of 5B70 aluminum alloy at different strain rates were investigated. The results show that as the strain rate increases, the elongation of the alloy decreases. Fracture analysis shows that the lower the strain rate, the greater are the number of dimples in the fracture and the deeper depth, showing obvious high ductile fracture. With the increase of strain rate, the quasi-cleavage plane appears, the alloy is biased towards brittle fracture. Secondary cracks also occur at lower strain rates. As the strain rate increases, the grain elongation on the side of the alloy fracture decreases, and a fine precipitate phase appears.

Key words: 5B70 aluminum alloy, strain rate, microstructure, quasi-cleavage fracture, fracture analysis

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