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Title: Strain development during the phase transition of La(Fe,Mn,Si){sub 13}H{sub z}

Abstract

We use powder X-ray diffraction to evaluate the temperature dependence of the crystalline properties during the magnetic phase transition of La(Fe,Mn,Si){sub 13}H{sub z} as a function of the Fe/Mn/Si ratio. Both the paramagnetic and ferromagnetic phases were observed as peak overlaps in the patterns around the Curie temperature (T{sub C}) occurring continuously in a temperature range of about 5 K around T{sub C.} Using the Williamson-Hall method, we evaluate the strain developing in the crystallites during the transition and find that it is associated with the growth of the paramagnetic phase as the transition occurs. Based on our measurements and microstructure analyses, we propose that cracking during the phase transition is due to or aggravated by the small content of a La-rich phase.

Authors:
; ; ; ;  [1];  [2]
  1. Department of Energy Conversion and Storage, Technical University of Denmark, Frederiksborgvej 399, DK-4000 Roskilde (Denmark)
  2. Department of Chemistry, Technical University of Denmark, Anker Engelunds Vej, DK-2800 Lyngby (Denmark)
Publication Date:
OSTI Identifier:
22594393
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 5; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CRACKING; CURIE POINT; IRON; LANTHANUM COMPOUNDS; MANGANESE; MICROSTRUCTURE; PARAMAGNETISM; PEAKS; PHASE TRANSFORMATIONS; POWDERS; SILICON; STRAINS; TEMPERATURE DEPENDENCE; TEMPERATURE RANGE; X RADIATION; X-RAY DIFFRACTION

Citation Formats

Neves Bez, Henrique, E-mail: hnbe@dtu.dk, Nielsen, Kaspar K., Smith, Anders, Norby, Poul, Bahl, Christian R. H., and Ståhl, Kenny. Strain development during the phase transition of La(Fe,Mn,Si){sub 13}H{sub z}. United States: N. p., 2016. Web. doi:10.1063/1.4960358.
Neves Bez, Henrique, E-mail: hnbe@dtu.dk, Nielsen, Kaspar K., Smith, Anders, Norby, Poul, Bahl, Christian R. H., & Ståhl, Kenny. Strain development during the phase transition of La(Fe,Mn,Si){sub 13}H{sub z}. United States. doi:10.1063/1.4960358.
Neves Bez, Henrique, E-mail: hnbe@dtu.dk, Nielsen, Kaspar K., Smith, Anders, Norby, Poul, Bahl, Christian R. H., and Ståhl, Kenny. 2016. "Strain development during the phase transition of La(Fe,Mn,Si){sub 13}H{sub z}". United States. doi:10.1063/1.4960358.
@article{osti_22594393,
title = {Strain development during the phase transition of La(Fe,Mn,Si){sub 13}H{sub z}},
author = {Neves Bez, Henrique, E-mail: hnbe@dtu.dk and Nielsen, Kaspar K. and Smith, Anders and Norby, Poul and Bahl, Christian R. H. and Ståhl, Kenny},
abstractNote = {We use powder X-ray diffraction to evaluate the temperature dependence of the crystalline properties during the magnetic phase transition of La(Fe,Mn,Si){sub 13}H{sub z} as a function of the Fe/Mn/Si ratio. Both the paramagnetic and ferromagnetic phases were observed as peak overlaps in the patterns around the Curie temperature (T{sub C}) occurring continuously in a temperature range of about 5 K around T{sub C.} Using the Williamson-Hall method, we evaluate the strain developing in the crystallites during the transition and find that it is associated with the growth of the paramagnetic phase as the transition occurs. Based on our measurements and microstructure analyses, we propose that cracking during the phase transition is due to or aggravated by the small content of a La-rich phase.},
doi = {10.1063/1.4960358},
journal = {Applied Physics Letters},
number = 5,
volume = 109,
place = {United States},
year = 2016,
month = 8
}
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