Magnetic properties and magnetocaloric effect in the HoNi1−Cu In (x=0, 0.1, 0.3, 0.4) intermetallic compounds

Abstract The magnetic properties and magnetocaloric effect (MCE) in HoNi 1− x Cu x In ( x =0, 0.1, 0.3, 0.4) compounds have been investigated. With the substitution of Cu for Ni, the Ho magnetic moment will cant from the c -axis, and form a complicated magnetic structure. These compounds exhibit two successive magnetic transitions with the increase in temperature. The large reversible magnetocaloric effects have been observed in HoNi 1− x Cu x In compounds around T ord , with no thermal and magnetic hysteresis loss. The large reversible isothermal magnetic entropy change (−Δ S M ) is 20.2 J/kg K and the refrigeration capacity (RC) reaches 356.7 J/kg for field changes of 5 T for HoNi 0.7 Cu 0.3 In. Especially, the value of −Δ S M (12.5 J/kg K) and the large RC (132 J/kg) are observed for field changes of 2 T for HoNi 0.9 Cu 0.1 In. Additionally, the values of RC are improved to 149 J/K for the field changes of 2 T due to a wide temperature span for the mix of HoNi 0.9 Cu 0.1 In and HoNi 0.7 Cu 0.3 In compounds with the mass ratio of 1:1. These compounds with excellent MCE are expected to have effective applications in magnetic refrigeration around 20 K.