Magnetic properties and magnetocaloric effect in the aluminide RENiAl2 (RE = Ho and Er) compounds.

Two single-phased aluminide RE NiAl 2 ( RE = Ho and Er) compounds have been synthesized by an arc-melting method. The magnetic properties and magnetocaloric effect (MCE) of HoNiAl 2 and ErNiAl 2 have been studied by magnetization measurements. A second-order paramagnetic (PM) to ferromagnetic (FM) phase transition together with a considerable reversible MCE were observed around the Curie temperature T C ∼7.5 K and 5.0 K for HoNiAl 2 and ErNiAl 2 , respectively. Under the magnetic field change (Δ H ) of 0–5 T, the maximal values of magnetic entropy change, refrigerant capacity and relative cooling power are 14.0 J/kg K, 171 J/kg, 213 J/kg for HoNiAl 2 and 21.2 J/kg K, 267 J/kg, 357 J/kg for ErNiAl 2 , respectively. [ABSTRACT FROM AUTHOR]