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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]

The magnetic cooling utilizing magneto-caloric effect is recognized as promising energy efficiency and environmentally friendly technology. Here we report a systematical study on the microstructures, magnetic properties and cryogenic magneto-caloric performances of the Gd20Ho20Tm20Cu20Ni20 amorphous ribbons. It is found that the ribbons reveal a second-order phase transition and are accompanied by a table-shaped magneto-caloric effect. The calculated magnetic-entropy-change maximum |ΔSM|, temperature averaged entropy change (i.e., TEC(10)), and refrigerant capacity reach 13.9 J/kg⋅K, 13.84 J/kg⋅K and 740 J/kg with magnetic field change of 0–7 T, respectively, indicating that the present Gd20Ho20Tm20Cu20Ni20 amorphous ribbons are good candidates for magnetic cooling. [ABSTRACT FROM AUTHOR]

We present a detailed investigation of the crystal structure, magnetism and magneto-caloric performances of RE Co 2 B 2 C (RE = Gd, Tb and Dy) compounds. All compounds are described with a LuNi 2 B 2 C-type crystallographic structure (I 4/ mmm space group). A second-ordered paramagnetic to ferromagnetic (PM-FM) transition is observed in RE Co 2 B 2 C compounds around their Curie temperatures (T C) of 17.2, 5.3 and 7.7 K, and induced a considerable magneto-caloric effect (MCE) for GdCo 2 B 2 C, TbCo 2 B 2 C and DyCo 2 B 2 C, respectively. The magneto-caloric performances for RE Co 2 B 2 C were characterized by the isothermal magnetic entropy (- Δ S M max) , temperature averaged entropy change (TEC) with three different temperature lifts (3, 5 and 10 K), and relative cooling power (RCP). The corresponding values of - Δ S M max , TEC (3 K) and RCP under the magnetic field change (Δ H) of 0–5 T, are 10.34 J/kg-K, 10.23 J/kg-K, and 238.1 J/kg for GdCo 2 B 2 C, 18.09 J/kg-K, 17.83 J/kg-K, and 438.2 J/kg for TbCo 2 B 2 C, as well as 17.79 J/kg-K, 17.72 J/kg-K, and 480.1 J/kg for DyCo 2 B 2 C, respectively. • Magnetic properties and MCE in RE Co 2 B 2 C compounds were studied. • Large values of -ΔS M max, TEC, RC and RCP were observed at low temperature. • RE Co 2 B 2 C compounds are competitive for cryogenic magnetic cooling. [ABSTRACT FROM AUTHOR]

In this work, polycrystalline oxides viz., Ho 2 CrMnO 6 (HCMO) and Er 2 CrMnO 6 (ECMO), were prepared using the sol-gel process, and their crystal structure, magnetic properties, and magnetocaloric effects (MCEs) were studied. X-ray refinement results demonstrate that both oxides exhibited the B -site disordered perovskite type structure (Pbnm space group). A ferromagnetic-paramagnetic phase transition as well as large reversible MCEs was also observed at Curie temperatures (T C) of ~6.1 and ~5.2 K for HCMO and ECMO, respectively. For a magnetic field change (ΔH) of 0–7 T, the maximum magnetic entropy change (-Δ S M), temperature-averaged entropy change (TEC 3), and relative cooling power (RCP) were estimated to be 11.03 J/kgK, 11.02 J/kgK, and 322.7 J/kg for HCMO, and 12.94 J/kgK, 12.80 J/kgK and 277.5 J/kg for ECMO. [ABSTRACT FROM AUTHOR]

• The RE 2 Ga 2 Mg (RE = Tm, Er, Ho) compounds were fabricated. • The magnetic and magnetocaloric properties were investigated. • Large conventional and inverse magnetocaloric effects were observed. • The Tm 2 Ga 2 Mg is considerable for cryogenic magnetic cooling. The Mo 2 FeB 2 -type compounds RE 2 Ga 2 Mg (RE = Tm, Er, Ho) (space group P 4/ mbm) exhibit a large magnetocaloric (MC) effect which makes them promising for use in cryogenic magnetic cooling applications. They exhibit low temperature metamagnetic nature below their Néel temperatures of 6.8, 11.7 and 18.4 K for Tm 2 Ga 2 Mg, Er 2 Ga 2 Mg and Ho 2 Ga 2 Mg, respectively. The magnetic entropy change, the temperature-averaged entropy change (3 K-lift), and the relative cooling power under a magnetic field change of 0–7 T are 15.6, 15.4 J/kgK and 275.8 J/kg for Tm 2 Ga 2 Mg; 13.2, 13.0 J/kgK and 268.0 J/kg for Er 2 Ga 2 Mg; as well as 9.1, 9.0 J/kgK and 223.0 J/kg for Ho 2 Ga 2 Mg, respectively. [ABSTRACT FROM AUTHOR]