Analysis of fracture toughness and microstructure of Al-Zn-Mg-Cu alloy in overaged condition

被引：0
|
作者：
Lin L. [1 ,2 ]
Liu Z. [2 ]
Han X. [1 ,2 ]
机构：
[1] School of Mechanical and Electronic Engineering, East China University of Technology, Nanchang
[2] School of Materials Science and Engineering, Central South University, Changsha
来源：
Zhongnan Daxue Xuebao (Ziran Kexue Ban)/Journal of Central South University (Science and Technology) | 2020年 / 51卷 / 02期
基金：
中国国家自然科学基金;
关键词：
Aluminum alloy; Fracture toughness; Overaging; η; phase;
D O I：
10.11817/j.issn.1672-7207.2020.02.004
中图分类号：
学科分类号：
摘要：
The mechanical properties and fracture behavior of an overaged Al-Zn-Mg-Cu alloy were investigated by tensile test, fracture toughness test, scanning electron microscopy and transmission electron microscopy. The relationship between the fracture toughness and yield strength of the studied alloy was studied, and the mechanism that the precipitates affected the fracture toughness was revealed. The results show that the fracture toughness of alloy is approximately inversely proportional to yield strength. With the increase of aging time, the precipitates within grain and on grain boundary becomes coarse and the work hardening exponent increases. Furthermore, the discrepancy of strength between the grain boundary and matrix diminishes with the coarsening of matrix precipitates, which promotes the homogeneity of deformation and therefore increases the fracture toughness. © 2020, Central South University Press. All right reserved.
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页码：301 / 308
页数：7
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