Publication detail
Ab initio study of properties of Co- and Cu- doped Ni-Mn-Ga alloys
ZELENÝ, M. SOZINOV, A. BJÖRKMAN, T. STRAKA, L. NIEMINEN, R. M.
Czech title
Ab initio studium vlastností slitiny Ni-Mn-Ga dopované Co a Cu
English title
Ab initio study of properties of Co- and Cu- doped Ni-Mn-Ga alloys
Type
conference paper
Language
en
Original abstract
The influence of Co and Cu doping on Ni-Mn-Ga alloy is investigated using the first-principles exact muffin-tin orbital method in combination with the coherent-potential approximation. The energy difference between the austenite (A) and the nonmodulated (NM) martensite ΔE_A-NM depends linearly on the Cu concentration and distribution, with a minimum for all Cu at Mn sites and a maximum for all Cu at Ga sites. For alloys simultaneously doped by Co in Ni sublattice and Cu in Mn or Ga sublattice, the effects of the individual dopants on ΔE_A-NM and (c/a)_NM and are almost independent. The alloy with composition Ni46Co4Mn24Ga22Cu4 exhibits decreased equilibrium (c/a)_NM and increased ΔE_A-NM in comparison with Ni50Mn25Ga25, which is in agreement with the previous experimental results.
Czech abstract
Vliv Co a Cu dopování na Ni-Mn-Ga slitinu je studován pomocí výpočtů z prvních principů metodou exaktních muffin-tin orbitalů (EMTO) v kombinaci s aproximací koherentního-potenciálu (CPA). Energetický rozdíl mezi austenitem (A) a nemodulovaným (NM) martenzitem ΔE_A-NM závisí lineárně na koncentraci a distribuci Cu, s minimem pro všechny Cu aomy v Mn podmřížce a maximem pro všechny Cu v Ga podmřížce. U slitin současně dopovaných i Co v Ni podmřížce a Cu v Mn nebo Ga podmřížce jsou účinky jednotlivých příměsí na ΔE_A-NM a (c/a) _NM téměř nezávislé. Slitina s složení Ni46Co4Mn24Ga22Cu4 vykazuje menší rovnovážnný tetrafonální poměr (c/a)_NM a větší ΔE_A-NM ve srovnání se slitinou Ni50Mn25Ga25, což je v souladu s předchozími experimentálními výsledky.
English abstract
The influence of Co and Cu doping on Ni-Mn-Ga alloy is investigated using the first-principles exact muffin-tin orbital method in combination with the coherent-potential approximation. The energy difference between the austenite (A) and the nonmodulated (NM) martensite ΔE_A-NM depends linearly on the Cu concentration and distribution, with a minimum for all Cu at Mn sites and a maximum for all Cu at Ga sites. For alloys simultaneously doped by Co in Ni sublattice and Cu in Mn or Ga sublattice, the effects of the individual dopants on ΔE_A-NM and (c/a)_NM and are almost independent. The alloy with composition Ni46Co4Mn24Ga22Cu4 exhibits decreased equilibrium (c/a)_NM and increased ΔE_A-NM in comparison with Ni50Mn25Ga25, which is in agreement with the previous experimental results.
Keywords in English
Magnetic shape memory alloys; martensitic phase transitions; tetragonal deformation; ab initio calculations;
RIV year
2015
Released
06.11.2015
Publisher
Elsevier Ltd.
ISSN
2214-7853
Book
International Conference on Martensitic Transformations, ICOMAT-2014
Volume
2
Number
S3
Pages from–to
S601–S604
Pages count
4
BIBTEX
@inproceedings{BUT118032,
author="Martin {Zelený} and Alexei {Sozinov} and Torbjörn {Björkman} and Ladislav {Straka} and Risto M. {Nieminen},
title="Ab initio study of properties of Co- and Cu- doped Ni-Mn-Ga alloys",
booktitle="International Conference on Martensitic Transformations, ICOMAT-2014",
year="2015",
volume="2",
number="S3",
month="November",
pages="S601--S604",
publisher="Elsevier Ltd. ",
issn="2214-7853"
}