Magnetic properties, magnetocaloric effect and refrigeration performance in RE ₆₀Al₂₀Ni₂₀ (RE = Tm, Er and Ho) amorphous ribbons

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 T_C∼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 T_C) 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 ΔT_lift (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.