On the determination of the magnetic entropy change in materials with first-order transitions

AbstractSome compositions of Ni-Mn-X (X = Ga, In, Sn) ferromagnetic shape memory alloys exhibit a first order magnetostructural phase transition. Magnetic entropy change ΔSm in the vicinity of this transition has been studied by magnetization and heat capacity measurements. Comparison of these results point to a large difference in magnitudes of ΔSm obtained from magnetization and heat capacity data. It is suggested that this discrepancy originates from overestimation of \Delta S_m determined from the magnetization measurements and underestimation of ΔSm obtained from the heat capacity measurements.

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Study of Magnetocaloric Properties of Ni-Mn-X (X = Ga, In) Heusler Alloys by Monte Carlo Technique

MRS Proceedings ◽

10.1557/proc-1200-g09-06 ◽

2009 ◽

Vol 1200 ◽

Author(s):

Vasiliy Buchelnikov ◽

Vladimir Sokolovskiy ◽

Sergey Taskaev ◽

Peter Entel

Keyword(s):

Experimental Data ◽

Phase Transition ◽

Monte Carlo ◽

Magnetic Entropy Change ◽

Heusler Alloys ◽

Entropy Change ◽

Magnetic Contribution ◽

Magnetic Entropy ◽

First Order ◽

Magnetocaloric Properties

AbstractTwo theoretical Monte Carlo models have been presented for description of the positive and negative magnetocaloric effects of Heusler Ni-Mn-X (X = Ga, In) alloys undergoing first order coupled magnetostructural phase transition. For both models all quantities such as temperature dependence of the magnetic contribution to the total specific heat, magnetization and isothermal magnetic entropy change are in qualitative agreement with the available experimental data.

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Large magnetic entropy change associated with the weakly first-order paramagnetic to ferrimagnetic transition in antiperovskite manganese nitride CuNMn3

Journal of Applied Physics ◽

10.1063/1.4890223 ◽

2014 ◽

Vol 116 (3) ◽

pp. 033902 ◽

Cited By ~ 5

Author(s):

C. Yang ◽

P. Tong ◽

J. C. Lin ◽

S. Lin ◽

D. P. Cui ◽

...

Keyword(s):

Magnetic Entropy Change ◽

Entropy Change ◽

Magnetic Entropy ◽

First Order ◽

Manganese Nitride

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Magnetic Phase Transition and Magnetic Proporties of LaFe11.6Si1.4Bx Compounds

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.750-752.919 ◽

2013 ◽

Vol 750-752 ◽

pp. 919-922

Author(s):

Kun Xie ◽

Yin Liu ◽

Mei Qing Cao ◽

Peng Cheng Xia ◽

Li Jie Yue

Keyword(s):

Phase Transition ◽

Curie Temperature ◽

Magnetic Phase Transition ◽

Magnetic Entropy Change ◽

Magnetic Phase ◽

Magnetic Transition ◽

Entropy Change ◽

Magnetic Entropy ◽

First Order ◽

Melt Spun

The magnetic phase transition and magnetic entropy change of melt-spun LaFe11.6Si1.4Bx(x=0.0, 0.3, 0.5, 0.7) ribbons were investigated by measuring the magnetization as the function of temperature. Comparing with LaFe11.6Si1.4, the NaZn13-type structure of LaFe11.6Si1.4Bxdid not change after introducing B atoms, while the amount of α-Fe phase in the ribbons significantly decreased. The Curie temperature slightly changes after the addition of B. The LaFe11.6Si1.4Bx(x=0.3, 0.5) exhibits first-order magnetic transition and large magnetic entropy change as observed in LaFe11.6Si1.4compound.

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