Phenomenological Modeling of Thermomagnetic Properties and Magnetocaloric Effect of (Mn$$_{0.6}$$Fe$$_{0.4}$$)NiSi$$_{1-x}$$Al$$_{x}$$ ($$x = 0.07$$ and 0.08) Alloys

We present a mean-field analysis, using the two-sublattice model, for the thermomagnetic and magnetocaloric properties of the R2Fe17C compounds, where R=Dy, Nd, Tb, Gd, Pr, Ho, Er and C is carbon. The dependence of magnetization, magnetic heat capacity, magnetic entropy and isothermal entropy change ∆Sm, are calculated for magnetic fields up to 5T and for temperatures up to 700 K . Direct magnetocaloric effect is present for all compounds with maximum ∆Sm between 6.13-10.95 J/K. mole for an applied field change of 5T. It is found that Pr2Fe17C compound has the highest ∆Sm of 10.95 J/K. mole at ∆H=5T and Tc=375 K. The inverse MCE is found in ferrimagnetic compounds, e.g. Gd2Fe17C, with ∆Sm= J/K mol at critical temperature Tc=623K and ∆Sm= J/K mol at Neel temperature TN=136 K. The calculated Arrott plots confirmed that the magnetic phase transitions in these compounds are of second order. The mean-field model proves its suitability for calculating the properties of the compounds under study.

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Phenomenological Modeling of Magnetocaloric Effect in La0.7SrxMnO3−δ

Journal of Superconductivity and Novel Magnetism ◽

10.1007/s10948-018-4605-z ◽

2018 ◽

Vol 31 (10) ◽

pp. 3357-3360 ◽

Cited By ~ 8

Author(s):

Adly H. El-Sayed ◽

Mahmoud A. Hamad

Keyword(s):

Magnetocaloric Effect ◽

Phenomenological Modeling

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Thermomagnetic properties and magnetocaloric effect of FeCoNiCrAl-type high-entropy alloys

AIP Advances ◽

10.1063/1.5079394 ◽

2019 ◽

Vol 9 (3) ◽

pp. 035010 ◽

Cited By ~ 5

Author(s):

Suok-Min Na ◽

Paul K. Lambert ◽

Hyunsoo Kim ◽

Johnpierre Paglione ◽

Nicholas J. Jones

Keyword(s):

Magnetocaloric Effect ◽

High Entropy Alloys ◽

High Entropy ◽

Thermomagnetic Properties

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Thermomagnetic Properties and Magnetocaloric Effect of R2Fe17C (R=Dy, Nd, Tb, Gd, Pr, Ho, Er) Compounds

International Journal of Computational Physics Series ◽

10.29167/a1i1p168-278 ◽

2018 ◽

Vol 1 (1) ◽

pp. 268-278

Author(s):

Ahmed Nagy ◽

Samy H. Aly ◽

Sherif Yehia ◽

Tareq Hammad

Keyword(s):

Magnetocaloric Effect ◽

Mean Field ◽

Entropy Change ◽

Field Analysis ◽

Magnetic Phase Transitions ◽

Mean Field Model ◽

Magnetocaloric Properties ◽

The Mean ◽

Thermomagnetic Properties ◽

Critical Temperature Tc

We present a mean-field analysis, using the two-sublattice model, for the thermomagnetic and magnetocaloric properties of the R2Fe17C compounds, where R=Dy, Nd, Tb, Gd, Pr, Ho, Er and C is carbon. The dependence of magnetization, magnetic heat capacity, magnetic entropy and isothermal entropy change ∆Sm, are calculated for magnetic fields up to 5T and for temperatures up to 700 K . Direct magnetocaloric effect is present for all compounds with maximum ∆Sm between 6.13-10.95 J/K. mole for an applied field change of 5T. It is found that Pr2Fe17C compound has the highest ∆Sm of 10.95 J/K. mole at ∆H=5T and Tc=375 K. The inverse MCE is found in ferrimagnetic compounds, e.g. Gd2Fe17C, with ∆Sm= J/K mol at critical temperature Tc=623K and ∆Sm= J/K mol at Neel temperature TN=136 K. The calculated Arrott plots confirmed that the magnetic phase transitions in these compounds are of second order. The mean-field model proves its suitability for calculating the properties of the compounds under study.

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