Large magnetocaloric effect in rapidly quenched Mn50− x Co x Ni40In10 nanomaterials

Abstract

The effect of Co addition on magnetic hysteresis, martensitic transformation temperature, and magnetic entropy change of rapidly-quenched Mn_50−x Co _x Ni₄₀In₁₀ alloy nanomaterials has been investigated. The melt-spun Mn₅₀Ni₄₀In₁₀ sample exhibits a small magnetic hysteresis which is further reduced by Co doping as measured between 0 and 2 T. The martensitic transformation temperature increases linearly with the electron concentration in the alloy from 195 K for Mn₅₀Ni₄₀In₁₀ to 378 K for Mn₄₅Co₅Ni₄₀In₁₀. The Mn₄₇Co₃Ni₄₀In₁₀ alloy, which has phase-transition temperature close to room temperature, exhibits a substantial peak entropy change of 29.7 J kg⁻¹ K⁻¹ at magnetic field change of 2 T. Our results demonstrate that Mn₄₇Co₃Ni₄₀In₁₀ nanomaterial exhibits promising magnetocaloric properties for near-room-temperature magnetic refrigeration.