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New (Er1 –xYx)0.8Sm0.2Fe2 multicomponent alloys with a substitution parameter of x = 0, 0.2, 0.4, 0.6, 0.8, and 1.0 are synthesized and their atomic crystal structure and magnetic properties are studied. It is shown that full magnetic compensation can be expected in the region of 0.2 < xcomp < 0.4. Er0.8Sm0.2Fe2 alloy exhibits temperature-dependent magnetization compensation at Tcomp = 400 K. [ABSTRACT FROM AUTHOR]

The structural and magnetic properties of the multicomponent R–Fe–H compounds with a high content of Fe and H are reported. The process of synthesis of the hydrides (R,R′)2Fe14BH5.5 [where R and R′ are light (Nd) and heavy (Dy, Ho, Er, Tm) rare earth metals, respectively] with a maximum hydrogen content is described in detail. The paper also provides insights into the synthesis of single-crystalline hydrides using the example of the R2(Fe,Co)14BH3 series. The hydrides (R,Nd)2Fe14BH5.5, R2(Fe,Co)14BH3, R2(Fe,Al)17H3 have a significantly increased volume as compared to the parent materials. High-field magnetization results of both parent and hydrogenated compounds at low temperatures are presented. Spin–reorientation phase transitions induced by an external magnetic field are observed. The parameter of the intersublattice exchange interaction and the influence of hydrogen on it are estimated within the framework of the mean field theory. The magnetocaloric effect of the compounds with a magnetic compensation point is studied with a special emphasis placed on the change of the sign of the effect. [ABSTRACT FROM AUTHOR]

The magnetic properties of rare-earth ferrimagnetic compounds Dy2Fe10Al7 and Ho2Fe10Al7 with a Th2Zn17 crystal structure have been studied. The temperature dependences of the magnetization and magnetocaloric effect have been examined in the temperature range of 4.2‒300 K in magnetic fields of up to 70 and 18 kOe, respectively. The temperatures of magnetic compensation of the magnetization of the rare-earth and iron sublattices have been determined. The magnetocaloric effect has been determined by the direct method. It has been found that the sign of the effect changes near the magnetic compensation point. This phenomenon has an application potential. [ABSTRACT FROM AUTHOR]

The paper presents the results of the synthesis, structural studies, and investigation of the magnetic and magnetostriction properties of new multicomponent alloys based on heavy rare-earth metals (R Yx)0.8Sm0.2Fe2, where R = Tb, Gd, Dy, and Er, х = 0, 0.2, 0.4, 0.6, 0.8, and 1. It was found that alloys of these systems (except for the system with Tb) are single-phase and have the cubic С15 Laves structure. The lattice parameters for all systems were shown to change linearly with increasing х. The main magnetic characteristics of the alloys were determined. The following practically important phenomena were found: the magnetic compensation of the sublattice magnetization, the spin reorientation, and the sign inversion of magnetostriction constants. [ABSTRACT FROM AUTHOR]

Highly effective materials are created for solid-state magnetic cooling in the range below room temperature (120–280 K). An investigation is performed of new (R,R')(Co,T)2 and R(Mn,T)Si (T = Fe, Co, Al) compounds and hydrides based on them that have a notable magnetocaloric effect (MCE) in the region of the Curie temperature. Main patterns of the behavior of an MCE depending on composition are revealed. [ABSTRACT FROM AUTHOR]

An investigation of the Y2Fe17 compound belonging to the class of intermetallic alloys of rareearth and 3d-transition metals is presented. The magnetization, magnetostriction, and thermal expansion of the Y2Fe17 single crystal were studied. The forced magnetostriction and magnetostriction constants were investigated in the temperature range of the magnetic ordering close to the room temperature. The giant field induced volume magnetostriction was discovered in the room temperature region in the magnetic field up to 1.2 T. The contributions of both anisotropic singleion and isotropic pair exchange interactions to the volume magnetostriction and magnetostriction constants were determined. The experimental results were interpreted within the framework of the Standard Theory of Magnetostriction and the Landau thermodynamic theory. It was found out that the giant values of the volume magnetostriction were caused by the strong dependence of the 3delectron Coulomb charge repulsion on the deformations and width of the 3d-electron energy band. [ABSTRACT FROM AUTHOR]

Synthesis of nanocrystalline and microcrystalline dysprosium was carried out. Temperature and field dependences of magnetocaloric effect were performed by direct method in field up to 1.2 T and temperature range 80-190 K. It was found that the nanocrystalline state leads to a significant reduction of the magnetic phase transition temperatures and to a small increase of the maximum value of the magnetocaloric effect in dysprosium. It is associated with the large amount of interface atoms in nanocrystalline Dy ribbons with a lower number of the nearest-neighbor atoms, causing the magnetic phase transition temperature decrease. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Highlights: [•] Systematic study of structure and magnetic properties of Y2(Fe,Mn)17-H systems was carried out. [•] Main regularities of magnetic behavior of hydrides were determined. [•] Hydrogen reinforces the Fe–Fe exchange interactions and, on the contrary, weakens the Fe–Mn and Mn–Mn ones. [ABSTRACT FROM AUTHOR]