From direct to inverse giant magnetocaloric effect in Co-doped NiMnGa multifunctional alloys
Result description
We report the magnetic and magnetocaloric properties in Co-doped Ni-Mn-Ga Heusler alloys around the Mn-rich composition Ni50Mn30Ga20. The presence of Co affects profoundly the critical temperatures and alters the exchange interactions of martensite and austenite to different extents by varying the composition it is possible to tune the critical temperatures and to induce a paramagnetic gap between the magnetically ordered martensite and magnetic austenite,thus giving rise to a reverse magnetostructuraltransformation.Contrary to the Co-free alloys,the saturation magnetization moment of austenite is strongly enhanced by Co with respect to the martensitic one:thus the magnetocaloric effect turns from direct into inverse.Remarkable values of the magneticproperties related to the magnetocaloric effect,e.g. the saturation magnetization jump at the transformation(DM) and the field dependence of the transformation temperature(dT/dH)are reported.
Keywords
Ni?Mn?Ga?Coferromagnetic shape memory alloysmagnetostructural transformationsmagnetic propertiesinverse magnetocaloric effect
The result's identifiers
Result code in IS VaVaI
Result on the web
DOI - Digital Object Identifier
Alternative languages
Result language
angličtina
Original language name
From direct to inverse giant magnetocaloric effect in Co-doped NiMnGa multifunctional alloys
Original language description
We report the magnetic and magnetocaloric properties in Co-doped Ni-Mn-Ga Heusler alloys around the Mn-rich composition Ni50Mn30Ga20. The presence of Co affects profoundly the critical temperatures and alters the exchange interactions of martensite and austenite to different extents by varying the composition it is possible to tune the critical temperatures and to induce a paramagnetic gap between the magnetically ordered martensite and magnetic austenite,thus giving rise to a reverse magnetostructuraltransformation.Contrary to the Co-free alloys,the saturation magnetization moment of austenite is strongly enhanced by Co with respect to the martensitic one:thus the magnetocaloric effect turns from direct into inverse.Remarkable values of the magneticproperties related to the magnetocaloric effect,e.g. the saturation magnetization jump at the transformation(DM) and the field dependence of the transformation temperature(dT/dH)are reported.
Czech name
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Czech description
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Classification
Type
Jx - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)
CEP classification
BM - Solid-state physics and magnetism
OECD FORD branch
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Result continuities
Project
Continuities
Z - Vyzkumny zamer (s odkazem do CEZ)
Others
Publication year
2011
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Acta Materialia
ISSN
1359-6454
e-ISSN
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Volume of the periodical
59
Issue of the periodical within the volume
1
Country of publishing house
GB - UNITED KINGDOM
Number of pages
8
Pages from-to
412-419
UT code for WoS article
000284789200042
EID of the result in the Scopus database
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Basic information
Result type
Jx - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)
CEP
BM - Solid-state physics and magnetism
Year of implementation
2011