Large Rotating Magnetocaloric Effects in Polycrystalline Ni-Mn-Ga Alloys

Polycrystalline Ni50.4Mn27.3Ga22.3 alloy with texture was prepared by conventional casting. The alloy exhibited enhanced magnetocrystalline anisotropy after superelastic training. Decent conventional magnetocaloric effect (MCE) with magnetic-field-induced entropy change ΔS = 9.2 J/kg·K under a magnetic field 30 kOe and inverse MCE with ΔS = 2.5 J/kg·K under 5 kOe were demonstrated when the field was applied parallel and perpendicular to , respectively. As a result, large rotating MCE with ΔS = 4.2 J/kg·K under a low field of 20 kOe was achieved at room temperature. This shows that polycrystalline Ni-Mn-Ga alloys may act as promising magnetic refrigerants.