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The magnetocaloric effect (MCE) and critical behavior in the RE PtMg (RE = Tb, Dy and Ho) intermetallic compounds around Curie temperatures T C were investigated by magnetization measurements. All the RE PtMg compounds exhibit pronounced MCE performance with the maximum magnetic entropy change (− Δ S M max ) values up to 5.1, 7.2, 10.2 J/kg K under the magnetic field change (Δ H) of 0–5 T around T C of 58, 29, and 20 K for RE = Tb, Dy and Ho, respectively. The reasonable and accurate critical exponents for the present RE PtMg series compounds for RE = Tb, Dy and Ho obtained by the Δ H dependence of Δ S M method are evaluated to be β = 0.4691, 0.4681, 0.4141, γ = 1.0412, 1.0482, 1.1067 and δ = 3.2196, 3.2393, 3.6728 around T C , which are verified by the Widom scaling law and scaling equations, respectively. • The magnetocaloric property in RE PtMg (RE = Tb, Dy and Ho) was studied. • A considerable reversible MCE was observed for all compounds. • The critical behavior in RE PtMg (RE = Tb, Dy and Ho) were studied. • The obtained critical exponents obey the Mean-field model. [ABSTRACT FROM AUTHOR]

Magnetic cooling (MC) by utilizing the magnetocaloric effect (MCE) has been considered as one of the most potential promising solid state alternative method to present well-used state-of-the-art gas compression cooling technique. In this work, the rare earth (RE)-rich indides Gd 6 Co 2.2 In 0.8 , Tb 6 Co 2.2 In 0.8 , Dy 6 Co 2.2 In 0.8 and Ho 6 Co 2.2 In 0.8 were fabricated and checked with respect to their crystal structure, magnetic properties and magnetocaloric performances. All the RE 6 Co 2.2 In 0.8 samples are crystallized with the orthorhombic Ho 6 Co 2 Ga-type structure and ordered magnetically. Considerable cryogenic magnetocaloric performances have been found. Around the magnetic transition temperatures of 76, 32, 50 and 18 K for Gd 6 Co 2.2 In 0.8 , Tb 6 Co 2.2 In 0.8 , Dy 6 Co 2.2 In 0.8 and Ho 6 Co 2.2 In 0.8 , the magnetic entropy change (Δ S M) peak values with a magnetic change (Δ H) equals to 0–70 kOe and the corresponding temperature averaged Δ S M (with 3 K-lift) are 11.84 and 11.82 J/kg-K, 8.96 and 8.80 J/kg-K, 9.59 and 9.54 J/kg-K, 20.83 and 20.38 J/kg-K for Gd 6 Co 2.2 In 0.8 , Tb 6 Co 2.2 In 0.8 , Dy 6 Co 2.2 In 0.8 and Ho 6 Co 2.2 In 0.8 , respectively. • The RE 6 Co 2.2 In 0.8 (RE = Gd, Tb, Dy, Ho) compounds are fabricated. • Magnetic properties and MCE in RE 6 Co 2.2 In 0.8 compounds were studied. • Considerable MCE parameters were observed at low temperature. [ABSTRACT FROM AUTHOR]

The layer-like RE 11 Ni 4 In 9 (RE = Gd, Dy and Ho) intermetallic compounds were successfully fabricated and systematically investigated concerning crystal structure, magnetic phase transitions and magnetocaloric effect (MCE). The RE 11 Ni 4 In 9 compounds crystallize in layer-like orthorhombic crystal structure (Cmmm space group) which is composed of CsCl-type and AlB 2 -type units with the ratio of 9 : 2. The RE 11 Ni 4 In 9 compounds present multiple magnetic phase transitions at low temperature. Except for the phase transition at low temperature region, the major phase transitions of the present series compounds are of second-ordered phase transitions (SOPTs). Around the magnetic phase transition temperatures at 91, 18 and 13.5 K for Gd 11 Ni 4 In 9 , Dy 11 Ni 4 In 9 and Ho 11 Ni 4 In 9 compounds, the values of peak magnetic entropy change (− Δ S M max) with magnetic flux density change Δ H = 0–7 T and the temperature averaged magnetic entropy change with 3 K lift are 3.58 and 3.55 J/kg-K, 6.02 and 5.94 J/kg-K, as well as 12.44 and 12.25 J/kg-K for Gd 11 Ni 4 In 9 , Dy 11 Ni 4 In 9 and Ho 11 Ni 4 In 9 compounds, respectively. The corresponding relative cooling power (refrigerant capacity) values are 269.0 (206.4), 194.9 (144.7), and 353.0 (269.2) J/kg, respectively. • The RE 11 Ni 4 In 9 (RE = Gd, Dy and Ho) intermetallic compounds are fabricated. • Magnetic properties and MCE in RE 11 Ni 4 In 9 amorphous ribbon were studied. • Considerable MCE parameters were observed at low temperature. [ABSTRACT FROM AUTHOR]

Abstract Polycrystalline double perovskite Y 2 CoMnO 6 oxides ceramics sintered at four different temperatures from 1000 °C to 1300 °C have been fabricated by conventional sol-gel method. All the Y 2 CoMnO 6 compounds are single phase with monoclinic structure (P 21 /n space group). The mean grain size grows significantly large and the shape becomes regular obviously with increasing sintering temperature. The effect of sintering temperature on magnetic properties of Y 2 CoMnO 6 compounds has been studied in detail. We found that the oxygen vacancies are introduced by sintering at high temperature has a certain influence on the magnetic properties. Moreover, the magnetic entropy changes (-∆ S M) as well as relative cooling power (RCP) in the double perovskite Y 2 CoMnO 6 oxides ceramics around paramagnetic to ferromagnetic transition were also investigated. [ABSTRACT FROM AUTHOR]

The rare-earths (RE) based materials with large magnetocaloric effect (MCE) have been recently recognized as potential candidates for practical solid-state magnetic refrigeration. In this work, the two light RE -based ternary RE Cu 2 Si 2 (RE = Nd and Pr) compounds were fabricated by arc-melting method and investigated the structural, magnetic and magnetocaloric properties. Both RE Cu 2 Si 2 compounds are found to crystallize in a ThCr 2 Si 2 -type layered crystal structure with the I 4/ mmm space group and undergo a field-induced first-ordered magnetic transition (MT) around 13.6 and 3.5 K for NdCu 2 Si 2 and PrCu 2 Si 2 , respectively. Large reversible MCE has been observed in both RE Cu 2 Si 2 compounds, and the magnetocaloric parameters of the maximum isothermal magnetic entropy change (-Δ S M max) and relative cooling power (RCP) with the magnetic field change (Δ H) of 0–7 T are determined to be 5.9 J/kg-K and 82.6 J/kg for NdCu 2 Si 2 compound and to be 8.0 J/kg-K and 67.2 J/kg for PrCu 2 Si 2 compound, respectively. • The ternary RE Cu 2 Si 2 (RE = Nd and Pr) compounds are synthesized. • Cryogenic magnetic properties in RE Cu 2 Si 2 were studied. • The magnetocaloric parameters in RE Cu 2 Si 2 compounds were determined. [ABSTRACT FROM AUTHOR]