Interfacial structure of MgO and MgAl2O4 with pure Al and their nucleation behavior

被引：0
|
作者：
Zhang D. [1 ]
Wang L. [1 ]
Xia M.-X. [1 ]
Li J.-G. [1 ]
机构：
[1] School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai
来源：
Xia, Ming-Xu (mingxu.xia@sjtu.edu.cn) | 2017年 / Central South University of Technology卷 / 27期
基金：
中国国家自然科学基金;
关键词：
AlMg; Interfacial reaction; Nucleation; Oxide;
D O I：
10.19476/j.ysxb.1004.0609.2017.08.01
中图分类号：
学科分类号：
摘要：
The nucleation behavior of common oxides MgO and MgAl2O4 in AlMg alloys were investigated by scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The results show that, at high temperatures, Al melt would react with MgO and MgAl2O4 substrates to formed Al2O3 at contacting interface. Among them, the reaction of Al/MgO is a multi-step reaction and MgAl2O4 is an intermediate reaction product. The interfacial reaction layer Al2O3 hinders liquid Al from contacting MgO or MgAl2O4 substrates, inhibiting their interfacial reaction to some extent. The interfacial reaction corrodes the exposed planes of original substrates, leading to scattered growth orientations of the new grains. TEM results of three detected nucleation interfaces Al/Al2O3, Al/MgO and Al/MgAl2O4 indicate that either new formed Al2O3 or original MgO and MgAl2O4 could all act as effective heterogeneous substrates to trigger nucleation process of Al, but with different nucleation potencies. © 2017, Science Press. All right reserved.
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页码：1535 / 1541
页数：6
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