Magnetostructural phase transitions and magnetocaloric effect in Tb-Dy-Ho-Co-Al alloys with a Laves phase structure

Journal Article · Thu Jul 07 04:00:00 EDT 2016 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4955047· OSTI ID:22597886

Chzhan, V. B. ^[1]; Tereshina, E. A. ^[2]; Khmelevskyi, S. ^[3]; Burkhanov, G. S. ^[1]; Ilyushin, A. S. ^[4]; Paukov, M. A.; Havela, L. ^[5]; Karpenkov, A. Yu. ^[6]; Cwik, J.; Koshkid'ko, Yu. S.; Miller, M. ^[7]; Nenkov, K.; Schultz, L. ^[8]

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1. Baikov Institute of Metallurgy and Material Sciences, Russian Academy of Sciences, Moscow 119991 (Russian Federation)
2. Institute of Physics CAS, Prague 18221 (Czech Republic)
3. Center for Computational Materials Science, IAP, Vienna University of Technology, Vienna A-1040 (Austria)
4. Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow 119991 (Russian Federation)
5. Faculty of Mathematics and Physics, Charles University, Prague 12116 (Czech Republic)
6. Physics Faculty, Tver State University, Tver 170100 (Russian Federation)
7. International Laboratory of High Magnetic Fields and Low Temperatures, Wroclaw 53-421 (Poland)
8. Leibniz-Institut fur Festkorper- und Werkstoffforschung, Dresden D-01171 (Germany)

The influence of simultaneous substitution within the rare earth (R) and Co sublattices on the structural, magnetic, and magnetocaloric properties of the Laves phase RCo{sub 2}-type compounds is studied. Main attention is devoted to the studies of the magnetostructural phase transitions and the transition types with respect to the alloy composition. Multicomponent alloys Tb{sub x}(Dy{sub 0.5}Ho{sub 0.5}){sub 1−x}Co{sub 2} and Tb{sub x}(Dy{sub 0.5}Ho{sub 0.5}){sub 1−x}Co{sub 1.75}Al{sub 0.25} were prepared with the use of high purity metals. Majority of the Tb{sub x}(Dy{sub 0.5}Ho{sub 0.5}){sub 1−x}Co{sub 2} alloys exhibit magnetic transitions of the first-order type and a large magnetocaloric effect. The substitution of Al for Co in Tb{sub x}(Dy{sub 0.5}Ho{sub 0.5}){sub 1−x}Co{sub 2} increases the Curie temperature (T{sub C}) but changes the transition type from first-to the second-order. The discussion of the physical mechanisms behind the observed phenomena is given on the basis of the first principles electronic-structure calculations taking into account both the atomic disorder and the magnetic disorder effects at finite temperatures. The advantage of Al-containing materials is that sufficiently high magnetocaloric effect values are preserved at T > T{sub C}.

• OSTI ID: 22597886
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 1 Vol. 120; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALUMINIUM ALLOYS
COBALT ALLOYS
CURIE POINT
DYSPROSIUM ALLOYS
ELECTRONIC STRUCTURE
HOLMIUM ALLOYS
IMPURITIES
LAVES PHASES
MAGNETIC PROPERTIES
PHASE TRANSFORMATIONS
RARE EARTHS
TERBIUM ALLOYS