Thermomagnetic Correlation in La0.85-xBixNa0.15MnO3 Soft Ferromagnet due to Nonmagnetic Bi3+ Substitution

AbstractWe report the structural, magnetic, and magnetocaloric properties of Bismuth (Bi)-substituted manganite La0.85-xBixNa0.15MnO3 (x=0, 0.1, 0.2, 0.25, and 0.3). X-ray diffraction data implicates the rhombohedral structure with $$ R\overline{3}c $$ R 3 ¯ c space group. Bi2O3 has helped in ensuring phase pure, densified compounds even at low sintering temperature and hence avoiding the evaporation of volatile sodium. The increase in grain size and decrease in magnetic transition temperature (TC) are due to the Bi chemical activity and electronic structure. The samples have shown indirect magnetic transformation from soft ferromagnet to canted ferromagnet/antiferromagnet with Bi. Griffiths phase-like behavior in the inverse magnetic susceptibility was observed for x=0.1; with further increase in Bi, the samples are found to develop the antiferromagnetic competing phase. The phenomenological model was used to model the thermomagnetic behavior of all the samples. The sample with x=0.1 shows an increase in magnetic entropy change upon Bi substitution and the maximum of magnetic entropy change is seen at 275K emphasizing its potential in room temperature magnetic refrigeration.

Download Full-text

Magnetocaloric Properties of Rapidly Solidified Ni51.1Mn31.2In17.7 Heusler Alloy Ribbons

MRS Proceedings ◽

10.1557/proc-1200-g07-05 ◽

2009 ◽

Vol 1200 ◽

Author(s):

Jose Sánchez Llamazares ◽

Blanca Hernando ◽

Víctor Prida ◽

Carlos García ◽

Caroline Ross

Keyword(s):

Melt Spinning ◽

Magnetic Entropy Change ◽

Magnetic Transition ◽

Entropy Change ◽

Single Step ◽

Magnetic Entropy ◽

Refrigerant Capacity ◽

Magnetocaloric Properties ◽

Room Temperature Magnetic Refrigeration ◽

Rapidly Solidified

AbstractMagnetic entropy change and refrigerant capacity have been determined for a field change of 20 kOe around the second-order magnetic transition of austenite in as-quenched Ni51.1Mn31.2In17.7 alloy ribbons produced by melt spinning technique. Samples crystallize in a single-phase austenite with the highly ordered L21-type crystal structure and a Curie temperature of 275 K. The material shows a maximum magnetic entropy change of ΔSMmax= - 1.7 Jkg-1K-1, an useful working temperature range of 78 K (δTFWHM) and a refrigerant capacity of RC=132 Jkg-1 (RC= │ΔSMmax│ x δTFWHM). The considerable RC value obtained together with the fabrication via a single-step process make austenitic Ni-Mn-In ribbons of potential interest as magnetic refrigerants for room temperature magnetic refrigeration.

Download Full-text

The Magnetocaloric Properties of Gd5Si4 Alloy Prepared by the New Method

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v4i3.6963 ◽

2014 ◽

Vol 4 (3) ◽

pp. 595-600 ◽

Cited By ~ 1

Author(s):

Z. Momeni Larimi

Keyword(s):

Magnetic Entropy Change ◽

Entropy Change ◽

New Method ◽

Second Phase ◽

Arc Furnace ◽

Magnetic Entropy ◽

Orthorhombic Structure ◽

X Ray Diffraction ◽

X Ray ◽

Magnetocaloric Properties

We report on a new method for preparation the magnetocaloric alloy Gd5Si4. By mechanical alloying under argonatmosphere and then melting sample by arc furnace, we produced the Gd5Si4 alloy. The structure and magnetothermalproperties of the alloy have been investigated with the help of powder X-ray diffraction and magnetization measurements.This compound crystallized in the orthorhombic structure with space group pnma. In X-ray powder diffraction pattern, aminor orthorhombic GdSi2 phase was observed as a second phase. For this compound, the second order phase transitionwas observed. The maximum isothermal magnetic entropy change of the Gd5Si4 compound at 348K was found to be -10J/(kg K) in an applied field of 0.5T.

Download Full-text

Untypical Temperature Dependence of the Magnetocaloric Effect in the Dy(Co1-xFex)2 (x = 0.10; 0.15) Compounds

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.233-234.247 ◽

2015 ◽

Vol 233-234 ◽

pp. 247-250 ◽

Cited By ~ 5

Author(s):

Maksim S. Anikin ◽

Evgeniy N. Tarasov ◽

Nikolay V. Kudrevatykh ◽

Aleksander V. Zinin

Keyword(s):

Magnetic Field ◽

Temperature Dependence ◽

Magnetic Entropy Change ◽

Magnetic Transition ◽

Iron Concentration ◽

Entropy Change ◽

Cooling Power ◽

X Ray Diffraction ◽

Magnetocaloric Properties ◽

Ordered State

A study of crystalline structure, magnetic and magnetocaloric properties of Dy(Co1-хFeх)2 (х = 0.10, 0.15) intermetallic compounds was undertaken. Phase composition was controlled by X-ray diffraction analysis. Magnetic properties were measured with a help of SQUID magnetometer in magnetic fields up to 7 Т in the temperature range from 4.2 K to 400 K. Magnetic transition temperatures from paramagnetic to magnetically ordered state were inferred as 288 K and 350 K, respectively. It is shown that at an increase of iron concentration and/or magnetic field intensity, a considerable maximum broadenings on a temperature dependence of magnetic entropy change is observed. The calculated value of the relative cooling power (RCP) of Dy(Co0.90Fe0.10)2, in a magnetic field of 1.7 T is equal to 152 J/kg that is close to that for Gd metal with RCP = 181 J/kg at μ0Н = 2 T.

Download Full-text

Exchange interactions and magnetocaloric effects of the Heusler alloys Ni–Mn–In–R (R = Fe, Co)

Modern Physics Letters B ◽

10.1142/s0217984918501464 ◽

2018 ◽

Vol 32 (14) ◽

pp. 1850146 ◽

Cited By ~ 1

Author(s):

Yan-Ru Li ◽

Hui-Ling Su ◽

Ji-Bing Sun ◽

Ying Li

Keyword(s):

Monte Carlo ◽

Transition Temperature ◽

Ab Initio ◽

Magnetic Entropy Change ◽

Magnetic Transition ◽

Heusler Alloys ◽

Entropy Change ◽

Magnetic Interactions ◽

Magnetic Entropy ◽

Magnetic Transition Temperature

The magnetic interactions and magnetocaloric effects in Ni2Mn[Formula: see text]In[Formula: see text]R[Formula: see text] (x = 0–0.2) (R = Fe, Co) Heusler alloys are investigated by the first-principles and Monte Carlo method. The ab initio calculations provide a basic understanding of the competition of ferromagnetic and antiferromagnetic interactions due to the chemical disorder of the alloy compositions. The thermodynamic properties including magnetization, specific heat and magnetic entropy change are calculated by the finite-temperature Monte Carlo simulations using the exchange couplings and magnetic moments from ab initio calculation as input parameters. The results show that the Fe or Co doping in Ni2Mn[Formula: see text]In[Formula: see text] leads to an increase of magnetic moment and magnetic entropy change but a decrease of magnetic transition temperature with the increase in the Fe or Co contents. This indicates that the transition temperature and magnetocaloric properties of Ni2Mn[Formula: see text]In[Formula: see text] alloy can be tuned by substituting In atom by Fe or Co with different contents.

Download Full-text

Magnetocaloric properties of Gd(Co1-xFex)2 compounds, with x ≤ 0.60

EPJ Web of Conferences ◽

10.1051/epjconf/201818505009 ◽

2018 ◽

Vol 185 ◽

pp. 05009

Author(s):

Maksim Anikin ◽

Evgeniy Tarasov ◽

Nikolay Kudrevatykh ◽

Aleksander Zinin

Keyword(s):

Phase Composition ◽

Diffraction Analysis ◽

Temperature Dependence ◽

Magnetic Entropy Change ◽

Entropy Change ◽

Specific Magnetization ◽

Magnetic Entropy ◽

X Ray Diffraction ◽

X Ray ◽

Magnetocaloric Properties

In this paper the results of specific magnetization and magnetocaloric effect (MCE) measurements for Gd(Co1-xFex)2 system upon the Co substitution by Fe for the x = 0 ÷ 0.60 range are presented. Phase composition was controlled by X-ray diffraction analysis. MCE has been studied within the temperature range of 300-850 K in magnetic fields up to 17 kOe by the magnetic entropy change calculation (ΔSm). It was found that in contrast to the previously studied R(Co-Fe)2 compounds where R = Dy, Ho, Er, an ordinary symmetrical peak of ΔSm(T) in the vicinity of TC is observed for presented samples. Additionally, the MCE comparison of Gd(Co0.88Fe0.12)2 with that for the isostructural Gd(Ni0.88Fe0.12)2 compound having a plateau-like ΔSm temperature dependence is given. The obtained results are discussed.

Download Full-text

The Magentocaloric Effect of Gd5Si2Ge2-XZnX Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.299-300.525 ◽

2011 ◽

Vol 299-300 ◽

pp. 525-529

Author(s):

Xue Ling Hou ◽

Jie Xiang ◽

Zhi Zeng ◽

Jian Huang ◽

Xue Zhen Wang ◽

...

Keyword(s):

Phase Structure ◽

Magnetic Entropy Change ◽

Entropy Change ◽

Vibrating Sample Magnetometer ◽

Magnetic Entropy ◽

X Ray Diffraction ◽

X Ray ◽

Type Phase ◽

Structural And Magnetic Properties ◽

Addition Amount

The structural and magnetic properties of arc-melted alloys of Gd5Si2Ge2-xZnxin vacuum were investigated by powder x-ray diffraction and Vibrating Sample Magnetometer. When the addition amount of Zn substituted for Ge is less than or equal to 0.05, the alloys have monoclinic Gd5Si2Ge2-type phase structure, the magnetic entropy change of Gd5Si2Ge2-xZnx alloys rapidly increase, When x=0.05, the alloy has the excellent magnetic entropy change (|SM|). When the addition amount of Zn substituted for Ge is more than 0.05, the alloys have the orthorhombic Gd5Si4-type phase structure, the magnetic entropy change of Gd5Si2-xGe2-xZnxalloys rapidly decreases. The Curie temperature (Tc) of Gd5Si2Ge2-xZnx alloys linearly increases and the peak of |SM| is broader with the Zn amount substituted for Ge in Gd5Si2Ge2-xZnxalloys in x range from 0-0.15.

Download Full-text

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.

Download Full-text

Magnetic, Magnetocaloric and Magnetoresonance Properties of (1-x)La0.7Sr0.3MnO3/xGeO2 (x=0, 0.15)

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.289.170 ◽

2019 ◽

Vol 289 ◽

pp. 170-176

Author(s):

Tatiana Gavrilova ◽

Ildar Gilmutdinov ◽

Ivan Yatsyk ◽

Tatiana Chupakhina ◽

Julia Deeva ◽

...

Keyword(s):

Magnetic Resonance ◽

Magnetic Entropy Change ◽

Magnetic Ordering ◽

Entropy Change ◽

Magnetic Entropy ◽

Anisotropic Particles ◽

X Ray Diffraction ◽

Absolute Value ◽

X Ray ◽

Magnetic Resonance Spectra

0.85La0.7Sr0.3MnO3/0.15GeO2composite material and pure La0.7Sr0.3MnO3were investigated by X-ray diffraction, scanning electron microscopy, magnetometry and magnetic resonance methods. It was observed that both samples demonstrate the ferromagnetic properties, while the absolute value of the magnetization, the magnetic entropy change and the magnetic ordering temperature decrease in composite in comparison with pure La0.7Sr0.3MnO3. The magnetic resonance spectra of investigated (1-x)La0.7Sr0.3MnO3/xGeO2(x=0, 0.15) can be attributed to the superposition of magnetic resonance spectra from magnetically anisotropic particles with different orientations.

Download Full-text

MAGNETOCALORIC EFFECT IN THE INTERMETALLIC COMPOUND Gd3Ni8Al

Modern Physics Letters B ◽

10.1142/s0217984912501679 ◽

2012 ◽

Vol 26 (25) ◽

pp. 1250167 ◽

Cited By ~ 1

Author(s):

M. X. WANG ◽

H. FU ◽

Q. ZHENG ◽

J. TANG

Keyword(s):

Intermetallic Compound ◽

Magnetocaloric Effect ◽

Single Phase ◽

Magnetic Entropy Change ◽

Magnetic Measurements ◽

Entropy Change ◽

Magnetic Entropy ◽

X Ray Diffraction ◽

X Ray ◽

Refrigerant Capacity

The magnetic properties and magnetocaloric effect of the polycrystalline Gd 3 Ni 8 Al intermetallic compound are studied in this paper. Powder X-ray diffraction shows that the alloy is CeNi 3-type single-phase structure. The magnetic measurements indicate that the compound is ferromagnetic and undergoes a second-order phase transition at 62 K. The maximum of magnetic entropy change reaches 11 J/kg K for the field change from 0 to 50 kOe and the refrigerant capacity of the titled compound is found to be 4.8×102 J/kg.

Download Full-text

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.

Download Full-text