Compositional Dependence of Curie Temperature and Magnetic Entropy Change in the Amorphous Tb–Co Ribbons

The Curie temperature (Tc) and magnetic entropy change (−ΔSm), and their relationship to the alloy composition of Tb–Co metallic glasses, were studied systematically in this paper. It was found that, in contrast to the situation in amorphous Gd–Co ribbons, the dependence of Tc on Tb content and the maximum −ΔSm vs. Tc -2/3 plots in Tb–Co binary amorphous alloys do not follow a linear relationship, both of which are supposed to be closely related to the non-linear compositional dependence of Tb–Co interaction due to the existence of orbital momentum in Tb.

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Effect of Co/Ni Substituting Fe on Magnetocaloric Properties of Fe-Based Bulk Metallic Glasses

Metals ◽

10.3390/met11060950 ◽

2021 ◽

Vol 11 (6) ◽

pp. 950

Author(s):

Jia Guo ◽

Lei Xie ◽

Cong Liu ◽

Qiang Li ◽

Juntao Huo ◽

...

Keyword(s):

Metallic Glasses ◽

Amorphous Alloys ◽

Magnetic Entropy Change ◽

Bulk Metallic Glasses ◽

Entropy Change ◽

Magnetic Entropy ◽

Glass Forming ◽

Magnetic Refrigerant ◽

Magnetocaloric Properties ◽

Curie Temperature Tc

In this work, Fe80-xMxP13C7 (M = Co, Ni; x = 0, 5 and 10 at.%) bulk metallic glasses (BMGs) were prepared, and the effect of the Co/Ni elements substitution for Fe on the magnetocaloric properties of Fe80P13C7 BMG has been investigated systematically. The Curie temperature (TC) of the present Fe-based BMGs increases with the substitution of Fe by Co/Ni. The magnetic entropy change (ΔSM) of the present Fe-based BMGs increases first and then decreases with the increase of Fe substituted by Co, but monotonically decreases with the increase of Fe substituted by Ni. Among the present Fe-based BMGs, the Fe75Co5P13C7 BMG exhibits the maximum ΔSM value of 5.21 J kg−1 K−1 at an applied field of 5 T, which is the largest value among Fe-based amorphous alloys without any rare earth elements reported so far. The present Fe-based BMGs exhibit the large glass forming ability, tunable TC and enhanced ΔSM value, which are beneficial for magnetic refrigerant materials.

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Enhanced Curie temperature and magnetic entropy change of Gd50Co50−xNix amorphous alloys

Modern Physics Letters B ◽

10.1142/s0217984920500505 ◽

2019 ◽

Vol 34 (04) ◽

pp. 2050050 ◽

Cited By ~ 1

Author(s):

M. N. Song ◽

L. W. Huang ◽

B. Z. Tang ◽

D. Ding ◽

Q. Zhou ◽

...

Keyword(s):

Magnetic Properties ◽

Amorphous Alloy ◽

Curie Temperature ◽

Binary Alloy ◽

Metallic Glasses ◽

Amorphous Alloys ◽

Magnetic Entropy Change ◽

Entropy Change ◽

Magnetic Entropy ◽

Ni Addition

Small amount of Ni was added in the [Formula: see text] binary alloy to replace the Co element for improving the formability and magnetic properties of the binary amorphous alloy. It was found that the glass formability of the [Formula: see text] amorphous alloy was significantly improved by Ni addition. The Curie temperature [Formula: see text] of the [Formula: see text] metallic glasses decreases with the Ni addition, and the maximum magnetic entropy change [Formula: see text] was also improved. The mechanism for the effect of adding a small quantity of Ni on the [Formula: see text] and [Formula: see text] of the [Formula: see text] amorphous alloy was studied.

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Formability and Magnetic Properties of the Binary Nd-Co Amorphous Alloys

Metals ◽

10.3390/met11111730 ◽

2021 ◽

Vol 11 (11) ◽

pp. 1730

Author(s):

Qiang Wang ◽

Ding Ding ◽

Lei Xia

Keyword(s):

Magnetic Properties ◽

Metallic Glasses ◽

Amorphous Alloys ◽

Melt Spinning ◽

Magnetic Entropy Change ◽

Glassy State ◽

Entropy Change ◽

High Coercivity ◽

Compositional Dependence ◽

Co Alloys

In this paper, binary Nd-Co alloys with compositional range from Nd72.5Co27.5 to Nd50Co50 were successfully vitrified into glassy state by a melt-spinning method. The glass formability of the metallic glasses (MGs) was studied and the best glass former in the binary Nd-Co alloys was obtained. Magnetic properties of the MGs were measured. The compositional dependence of Curie temperature of the MGs was observed. The mechanism for the spin-glass-like behaviors and high coercivity at low temperature, and their influence on the magnetic entropy change of the MGs, were investigated.

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Magnetic properties of the non-stoichiometric TbCo2Nix alloys

EPJ Web of Conferences ◽

10.1051/epjconf/201818504021 ◽

2018 ◽

Vol 185 ◽

pp. 04021

Author(s):

Alexander Inishev ◽

Evgeny Gerasimov ◽

Nikolay Mushnikov ◽

Pavel Terentev ◽

Vasily Gaviko

Keyword(s):

Magnetic Properties ◽

Curie Temperature ◽

Concentration Dependence ◽

Magnetic Moment ◽

Magnetic Entropy Change ◽

Entropy Change ◽

Magnetic Entropy ◽

Thermodynamic Relation ◽

Temperature Dependences

The magnetic and magnetothermal properties of the non-stoichiometric TbCo2Nix (0 ≤ x ≤ 0.2) alloys were studied. It was found that the concentration dependence of the Curie temperature and magnetic moment of the 3d-sublattice have a maximum at x = 0.025. The obtained experimental magnetic properties of the TbCo2Nix alloys were discussed under assumption that the Co magnetic moment in the compounds changes with increasing x. The magnetic entropy change was determined using the temperature dependences of the magnetization and Maxwell’s thermodynamic relation. The obtained results for TbCo2Nix were compared with those for the ErCo2Mnx alloys.

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Study of Magnetic Transition and Magnetocaloric Effect in La1-xSrxMnO3 (0.20≤ x ≤0.35) Compounds

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.378.225 ◽

2013 ◽

Vol 378 ◽

pp. 225-229 ◽

Cited By ~ 1

Author(s):

Yeong Seung Jeong ◽

M.S. Anwar ◽

Faheem Ahmed ◽

Seung Rok Lee ◽

Bon Heun Koo

Keyword(s):

Curie Temperature ◽

Magnetic Entropy Change ◽

Perovskite Phase ◽

Magnetic Transition ◽

Entropy Change ◽

Solid State Reaction Method ◽

Magnetic Entropy ◽

Conventional Solid State Reaction ◽

Ionic Radii ◽

The Difference

We report the magnetic transition and large magnetic entropy change in Sr doped lanthanum manganites. Polycrystalline La1-xSrxMnO3(0.20x0.35) samples were prepared using the conventional solid-state reaction method. The results of X-ray diffraction indicates perovskite phase without any impurity. The magnetic study has revealed that the Curie temperature is influenced by Sr-concentration. The doping of Sr at La site affects the Mn-O bond length and Mn-O-Mn bond angle due to the difference in their ionic radii, consequently, the Curie temperature changed. A large magnetic entropy change has been observed for La0.8Sr0.2MnO3sample, the value of the maximum entropy change (SMmax) increases from 1.42 to 2.74 J/kgK as magnetic field increases from 1 to 2.5 T. This investigation suggests that La1-xSrxMnO3can be used as a potential magnetic refrigeration material.

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Study on Influence of Ca2+ Ions Doping at a Site on Magnetic Properties and Magnetocaloric Effect of Nominal Compositions La1.4Sr1.6-xCaxMn2O7

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1120-1121.406 ◽

2015 ◽

Vol 1120-1121 ◽

pp. 406-413 ◽

Cited By ~ 1

Author(s):

Yun Zong ◽

Di Kang

Keyword(s):

Curie Temperature ◽

Manganese Oxides ◽

Magnetic Entropy Change ◽

Entropy Change ◽

Xrd Analysis ◽

Layered Perovskite ◽

Magnetic Entropy ◽

Doping Amount ◽

Space Group ◽

Room Temperature Magnetic Refrigeration

Polycrystalline layered perovskite manganese oxides La1.4Sr1.6-xCaxMn2O7 (x=0,0.2,0.4,0.8,1.0,1.4,1.6) samples is prepared using solid state reaction.The XRD analysis shows that La1.4Sr1.6-xCaxMn2O7 (0 ≤ x ≤ 0.8) samples are Sr3Ti2O7-type tetragonal structure with space group I4/mmm and forms a layered perovskite structure; for the 1.0≤ x ≤1.6 series of samples the main phase is ABO3 type orthorhombic structure with space group Pbnm.For small amount of Ca2+ ion-doped sample (x= 0.2,0.4), induce serious Jahn-Teller(J-T) distortion of MnO6 octahedral.For a large number of doping (1.0≤ x ≤1.6) samples, ferromagnetic - paramagnetic transition occurs near the Curie temperature (Tc) from low to high temperatures.With increasing doping amount, the magnetization reached maximum at x=1.4 samples.Maximum magnetic entropy change of the three samples(x=1.0,1.4,1.6) reaches 0.84, 1.20 and 2.28 J kg-1 K-1 at 320,268 and 215K near the Curie temperature, respectively. The large magnetic entropy change effect under low magnetic field of the sample makes it an optimal candidate of room temperature magnetic refrigeration materials.

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Field Dependence of the Refrigerant Capacity for La0.6Ca0.4MnO3 Manganite

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.154.163 ◽

2009 ◽

Vol 154 ◽

pp. 163-168 ◽

Cited By ~ 1

Author(s):

R.A. Szymczak ◽

Aleksandra Kolano-Burian ◽

Roman Kolano ◽

R. Puzniak ◽

V.P. Dyakonov ◽

...

Keyword(s):

Magnetic Field ◽

Curie Temperature ◽

Statistical Model ◽

Magnetic Entropy Change ◽

Entropy Change ◽

Relative Cooling Power ◽

Cooling Power ◽

Magnetic Entropy ◽

Refrigerant Capacity ◽

Jahn Teller

The magnetocaloric effect in La0.6Ca0.4MnO3 manganite has been investigated. The isothermal magnetization versus applied magnetic field at various temperatures in the vicinity of Curie temperature was measured, and the temperature dependence of magnetic entropy change was determined using Maxwell’s relation. This value is comparable to that in Gd. Nevertheless, the relative cooling power of La0.6Ca0.4MnO3 was shown to be considerably lower than that of Gd. The experimental results have been analyzed in frames of a phenomenological statistical model. This model considers explicitly Jahn-Teller interactions and allows prediction of the field dependences of the magnetic entropy change and the relative cooling power.

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