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Title: Pressure-induced polyamorphism by quantitative structure factor and pair distribution function analysis in two Ce-based metallic glasses

Abstract

We utilized the pair distribution function method to characterize the pressure-induced polyamorphic transition in Ce60Al20Cu20 and Ce55Al45 metallic glass at room temperature. Using synchrotron high-energy x-ray diffraction we collected scattering information from a large Q-space coverage, which in turn gave a high resolution g(r) that provided accurate local structure information. We observed a sudden change in compressibility and the nearest neighbor distance at 3.50–6.32 GPa for Ce60Al20Cu20 and 2.20–6.89 GPa for Ce55Al45. The origin of the volume collapse seemed to be pressure-induced qualitative changes in bond shortening that corresponded to different coordination spheres. The polyamorphic transitions in these two systems from low-density glass (LDG) to high-density glass (HDG) are associated with local atomic rearrangements.

Authors:
ORCiD logo; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1409588
Report Number(s):
BNL-114640-2017-JA¿¿¿
Journal ID: ISSN 0925-8388
DOE Contract Number:
SC0012704
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Alloys and Compounds; Journal Volume: 695; Journal Issue: C
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; metallic glasses; pair distribution function; polyamorphism; high pressure

Citation Formats

Zhang, Linji, Sun, Fei, Hong, Xinguo, Wang, Junlong, Liu, Gang, Kong, Lingping, Yang, Hongwang, Liu, Xiuru, Zhao, Yong, and Yang, Wenge. Pressure-induced polyamorphism by quantitative structure factor and pair distribution function analysis in two Ce-based metallic glasses. United States: N. p., 2017. Web. doi:10.1016/j.jallcom.2016.10.246.
Zhang, Linji, Sun, Fei, Hong, Xinguo, Wang, Junlong, Liu, Gang, Kong, Lingping, Yang, Hongwang, Liu, Xiuru, Zhao, Yong, & Yang, Wenge. Pressure-induced polyamorphism by quantitative structure factor and pair distribution function analysis in two Ce-based metallic glasses. United States. doi:10.1016/j.jallcom.2016.10.246.
Zhang, Linji, Sun, Fei, Hong, Xinguo, Wang, Junlong, Liu, Gang, Kong, Lingping, Yang, Hongwang, Liu, Xiuru, Zhao, Yong, and Yang, Wenge. Wed . "Pressure-induced polyamorphism by quantitative structure factor and pair distribution function analysis in two Ce-based metallic glasses". United States. doi:10.1016/j.jallcom.2016.10.246.
@article{osti_1409588,
title = {Pressure-induced polyamorphism by quantitative structure factor and pair distribution function analysis in two Ce-based metallic glasses},
author = {Zhang, Linji and Sun, Fei and Hong, Xinguo and Wang, Junlong and Liu, Gang and Kong, Lingping and Yang, Hongwang and Liu, Xiuru and Zhao, Yong and Yang, Wenge},
abstractNote = {We utilized the pair distribution function method to characterize the pressure-induced polyamorphic transition in Ce60Al20Cu20 and Ce55Al45 metallic glass at room temperature. Using synchrotron high-energy x-ray diffraction we collected scattering information from a large Q-space coverage, which in turn gave a high resolution g(r) that provided accurate local structure information. We observed a sudden change in compressibility and the nearest neighbor distance at 3.50–6.32 GPa for Ce60Al20Cu20 and 2.20–6.89 GPa for Ce55Al45. The origin of the volume collapse seemed to be pressure-induced qualitative changes in bond shortening that corresponded to different coordination spheres. The polyamorphic transitions in these two systems from low-density glass (LDG) to high-density glass (HDG) are associated with local atomic rearrangements.},
doi = {10.1016/j.jallcom.2016.10.246},
journal = {Journal of Alloys and Compounds},
number = C,
volume = 695,
place = {United States},
year = {Wed Feb 01 00:00:00 EST 2017},
month = {Wed Feb 01 00:00:00 EST 2017}
}
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