Precipitate crystal structure determination in melt spun Mg-1.5wt%Ca-6wt%Zn alloy

被引：53

作者：

Jardim, PM

Solórzano, G

Vander Sande, JB

机构：

[1] Pontificia Univ Catolica Rio de Janeiro, Dept Mat Sci & Met, BR-22452 Rio De Janeiro, Brazil

[2] MIT, Dept Mat Sci & Engn, Cambridge, MA 02139 USA

来源：

MICROSCOPY AND MICROANALYSIS | 2002年 / 8卷 / 06期

关键词：

crystal structure determination; transmission electron microscopy; Mg alloys; melt spinning; precipitation on dislocations; high-resolution electron microscopy; image simulation; electron-diffraction pattern simulation;

D O I：

10.1017/S1431927602010413

中图分类号：

T [工业技术];

学科分类号：

08 [工学];

摘要：

A melt-spun Mg-1.5%wtCa-6wt%Zn alloy was analyzed by means of transmission electron microscopy, energy dispersive X-ray spectroscopy, and scanning transmission electron microscopy. The as-solidified alloy exhibited both spherical matrix precipitates and elongated precipitates at the grain boundaries (grain-boundary films). After heat treatment, the alloy showed faceted precipitates (cuboidal shape), mostly on dislocations. It was found that the observed precipitates are the same compound, Ca2Mg6Zn3. As there was no crystallographic data for this compound in the literature, its crystal structure was investigated by comparison of experimental and simulated selected-area electron-diffraction patterns and high-resolution electron microscopy images. This study indicated that Ca2Mg6Zn3 is a trigonal compound with space group P((3) over bar)1c and lattice parameters a=0.97 nm, c=1.0 nm.

引用

页码：487 / 496

页数：10

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