Strengthening Al-Zn-Mg Alloys via Ultra-Fine Lamella Structures Containing a High Density of Dislocations and Clusters

被引：3

作者：

Qin, Yonggui ^{[1
]}

Lin, Sicong ^{[1
]}

Jin, Shenbao ^{[1
]}

Liu, Jizi ^{[1
,2
,3
]}

机构：

[1] Nanjing Univ Sci & Technol, Sch Mat Sci & Engn, Mat Characterizat & Res Ctr, Nanjing 210094, Jiangsu, Peoples R China

[2] Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China

[3] Nanjing Univ Sci & Technol, Sch Mat Sci & Engn, Nano & Heterogeneous Mat Ctr, Nanjing 210094, Jiangsu, Peoples R China

来源：

METALS | 2019年 / 9卷 / 02期

基金：

中国国家自然科学基金; 国家重点研发计划;

关键词：

Al-Zn-Mg alloy; UFG; lamella structure; thermo-mechanical processing; dislocation; precipitate; RESOLUTION ELECTRON-MICROSCOPY; MECHANICAL-PROPERTIES; PRECIPITATION SCENARIOS; ALZNMG(CU) ALLOYS; 7075; ALUMINUM; DUCTILITY; BEHAVIORS;

D O I：

10.3390/met9020140

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

A new method of thermo-mechanical processing has been designed by introducing pre-aging before general cold rolling for an Al-Zn-Mg alloy. This process results in an increase of 200 MPa in yield strength compared to that of the peak-aged samples. The microstructures were examined by transmission electron microscope and X-ray diffraction. It has been found that the enhanced strength is mainly contributed to by ultra-fine lamella structures containing a high density of dislocations pinned by nanoprecipitates. Extra strength is provided by the "interlocking" of precipitates and dislocations. Fractographic features analysis shows that crack propagation along the interface of the lamella structures is the direct reason for resulting in fracture, due to intra-granular strength exceeding grain boundary cohesion.

引用

页数：9

共 24 条

[21] X-RAY LINE BROADENING FROM FILED ALUMINIUM AND WOLFRAM [J].