Dislocation pile-ups at β1 precipitate interfaces in Mg-rare earth (RE) alloys

被引：38

作者：

Huang, Zhihua ^{[1
]}

Yang, Chaoming ^{[1
]}

Qi, Liang ^{[1
]}

Allison, John E. ^{[1
]}

Misra, Amit ^{[1
]}

机构：

[1] Univ Michigan, Dept Mat Sci & Engn, Ann Arbor, MI 48109 USA

来源：

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING | 2019年 / 742卷

关键词：

Magnesium; in situ transmission electron microscopy (TEM); Dislocation; ND; MAGNESIUM; ENERGY;

D O I：

10.1016/j.msea.2018.10.104

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

The local confinement of slip in a magnesium matrix by arrays of planar prismatic beta(1) precipitates in a dilute, over-aged Mg-Nd alloy is studied using transmission electron microscopy (TEM). In situ indentation in TEM shows that matrix dislocations pile-up at precipitate interfaces in the confined regions. Analysis of the images from the in situ experiments as well as post mortem TEM of bulk compression samples reveals that, in the presence of a dislocation pile-up of sufficient intensity, slip is transmitted through the beta(1) precipitates. This impediment to dislocation motion from planar precipitate facets is analyzed using dislocation theory and density functional theory calculations. It is shown that the beta(1) precipitate "walls" result in a strong but not impenetrable barrier to slip transmission.

引用

页码：278 / 286

页数：9

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