Magnetocaloric Effect in Ni-Cu-Mn-Gd-Ga Alloy. XI Symposium of Magnetic Measurements

The magnetocaloric eect of the NiCuMnGdGa polycrystalline alloy was investigated.The nominal composition of the alloy was Ni50Cu6.25Mn16.75Ga25Gd2at.%.The X-ray diraction studies revealed presence of two phases at room temperature.This was conrmed by magnetic measurements conducted in low eld of 4 kA/m (50 Oe), which showed two Curie transition temperatures, one in vicinity and the other one well above the room temperature.The analysis of isothermal magnetic curves allowed the calculation of magnetic entropy change (∆SM ).Although the peak value of |∆SM | is relatively low, ≈1.1 J/(kg K), it is very broad.The adiabatic temperature change (∆T ) measured near room temperature is ≈0.49K.Such result is irrespective of the magnetizingdemagnetizing cycle frequency which varied from 2/min to 10/min.