Polytypic phase formation in DyAl sub 3 by rapid solidification

Amorphous ribbons of Al{sub {ital x}}Dy{sub 100{minus}{ital x}}, 93{gt}{ital x}{gt}85, were obtained by melt spinning. During crystallization, in addition to Al, four different metastable crystalline phases of DyAl{sub 3} were observed. These phases are, in order of appearance, the high-pressure fac...

Full description

Saved in:
Bibliographic Details
Published in:Applied physics letters 1991-01, Vol.58:2
Main Authors: Xu, Y., Altounian, Z., Muir, W.B.
Format: Article
Language:English
Subjects:
360102 - Metals & Alloys- Structure & Phase Studies
ALLOYS
ALUMINIUM ALLOYS
CRYSTAL STRUCTURE
CRYSTAL-PHASE TRANSFORMATIONS
CRYSTALLIZATION
DIAGRAMS
DYSPROSIUM ALLOYS
LATTICE PARAMETERS
MATERIALS SCIENCE
PHASE DIAGRAMS
PHASE TRANSFORMATIONS
RARE EARTH ALLOYS
SOLIDIFICATION
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Amorphous ribbons of Al{sub {ital x}}Dy{sub 100{minus}{ital x}}, 93{gt}{ital x}{gt}85, were obtained by melt spinning. During crystallization, in addition to Al, four different metastable crystalline phases of DyAl{sub 3} were observed. These phases are, in order of appearance, the high-pressure face-centered cubic phase, {gamma}-DyAl{sub 3} and three polytypic rhombohedral phases, {beta}-DyAl{sub 3}, {beta}{prime}-DyAl{sub 3}, and {alpha}{prime}-DyAl{sub 3}. It is the first time that the {beta}{prime} phase in rare-earth trialuminides and the {alpha}{prime} phase in Dy-Al alloy system have been observed. It is shown that all these phases are associated with the polytypic packing of the hexagonal DyAl{sub 3} atomic layers. The relative stability of the phases is found to be related to the hexagonal to cubic stacking ratio in the structure.
ISSN:0003-6951
1077-3118
DOI:10.1063/1.104948