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Rare-earth based amorphous alloys with promising glass forming ability (GFA) and considerable magnetocaloric effect (MCE) are extensively exploited for magnetic refrigeration (MR) materials. Here, the GFA, magnetic properties, MCE, and refrigeration performance of RE60Al20Ni20 (RE = Tm, Er, and Ho) amorphous ribbons were investigated. A magnetic phase transition (paramagnetic to ferromagnetic, second-order) with ignorable field and thermal hysteresis was found around TC ∼ 4.4 K for Tm60Al20Ni20, ∼9.5 K for Er60Al20Ni20, and ∼17.9 K for Ho60Al20Ni20. For a field change ΔH = 50 kOe, the MCE parameters of the maximal magnetic entropy change (around their own TC) and relative cooling power are 14.1 J/kg K and 235 J/kg for Tm60Al20Ni20, 14.3 J/kg K and 372 J/kg for Er60Al20Ni20, and 12.4 J/kg K and 460 J/kg for Ho60Al20Ni20. In addition, the temperature averaged entropy change at ΔTlift (temperature span) of 2 K and 5 K is investigated, very close values and similar field dependence with magnetic entropy change indicating that RE60Al20Ni20 (RE = Tm, Er, and Ho) has potential applications in cryogenic magnetic refrigeration. [ABSTRACT FROM AUTHOR]

In this paper, a detailed investigation with respect to the structural, cryogenic magnetic properties and magnetocaloric performances of RE 2 CuMnO 6 (RE = Gd, Dy, Ho and Er) double perovskite (DP) compounds has been performed. All the RE 2 CuMnO 6 compounds are confirmed to B -site disordered and crystallized in the GdFeO 3 -type structure (Pnma space group, N 62, oP20). The magnetic transition temperatures (T M) are found to be ~7.5 K for Gd 2 CuMnO 6 , ~12.1 K for Dy 2 CuMnO 6 , ~12.2 K for Ho 2 CuMnO 6 , and ~3.6 K for Er 2 CuMnO 6 , respectively. Moreover, for checking the magnetocaloric performances several vital parameters including -Δ S M max (peak value of magnetic entropy change, -Δ S M), TEC (3) (temperature averaged -Δ S M) and RCP (relative cooling powers) are evaluated to be 7.84, 7.73 J/kgK and 151.1 J/kg for Gd 2 CuMnO 6 , 5.69, 5.59 J/kgK and 180.9 J/kg for Dy 2 CuMnO 6 , 7.12, 7.05 J/kgK and 192.4 J/kg for Ho 2 CuMnO 6 , as well as 9.92, 9.60 J/kgK and 195.9 J/kg for Er 2 CuMnO 6 under the magnetic field change Δ H = 5 T, respectively. [ABSTRACT FROM AUTHOR]

Abstract It is well known that rare earth (RE) based intermetallic compounds reveal various interesting magnetic properties depending on the crystallized structures and the constituent elements, paving the way for potential applications in different fields. Recent progresses regarding magnetic properties and magnetocaloric effect (MCE) in ternary rare earth RE 2 T 2 X (RE = Gd-Tm; T = Cu, Ni, Co; and X = Cd, In, Ga, Sn, Al) intermetallic compounds are reviewed in this paper. Some of them exhibit excellent MCE performances which make them attractive in the field of magnetic refrigeration at low temperature. With the aim of understanding the magnetocaloric characteristics of RE 2 T 2 X compounds, the crystal structure, magnetism and magnetic phase transition are also focused. The origin of the MCE together with the physics behind and the potential application of RE 2 T 2 X compounds are thoroughly considered. Highlights • Magnetic and magnetocaloric properties in RE 2 T2X compounds are reviewed. • The RE 2 T2X compounds show four types of crystallize structures. • Some of them exhibit excellent cryogenic magnetocaloric performances. • The origin of magnetocaloric effect in RE 2 T2X compounds is discussed. [ABSTRACT FROM AUTHOR]

The magnetic properties and magnetocaloric effect (MCE) in antiferromagnetic non-superconducting TbNiBC compound have been investigated in detail. Under low magnetic field changes and at low temperatures, the studied compound shows an inverse MCE which is due to the fact of antiferromagnetic ground state, whereas a normal reversible MCE under high magnetic field changes is observed which is related to the field-induced first-order metamagnetic transition from antiferromagnetic to ferromagnetic states. For the magnetic field change of 0-7 T the values of maximal magnetic entropy change ( $-\Delta S_{\mathrm {M}}^{\max } )$ , refrigerant capacity (RC) and relative cooling power (RCP) for the present TbNiBC are evaluated to be 11.1 J/kg/K, 225 J/kg and 296 J/kg, respectively. [ABSTRACT FROM AUTHOR]

The magnetic and magnetocaloric properties in GdNiBC compound have been investigated by magnetization and heat capacity measurements. The compound exhibits a paramagnetic to ferromagnetic transition at TC\sim 15 K. A large reversible magnetocaloric effect has been observed and accompanied by a second-order magnetic phase transition at TC . The maximum magnetic entropy change ( -\Delta SM^{\mathrm {max}} ) and adiabatic temperature change ( \Delta T\mathrm {ad}^{\mathrm {max}} ) are 24.9 J/kg K and 13 K, for a magnetic field change of 0–7 T, respectively. The corresponding relative cooling power is 801 J/kg. [ABSTRACT FROM AUTHOR]