Magnetic Properties and Magnetocaloric Effect of Nd_(0.7)Gd_(0.3)Mn_2Si_2 Alloy

摘要

In this work, crystal structure, magnetic properties and magnetocaloric effect of Nd_(0.7)Gd_(0.3)Mn_2Si_2 alloy were studied by X-ray diffraction (XRD), Physical Property Measurement System (PPMS) and Differential Scanning Calorimetry (DSC). Nd_(0.7)Gd_(0.3)Mn_2Si_2 crystallizes in ThCr_2Si_2-typed structure with space group I4/mmm, in which the Nd, Gd, Mn and Si atoms occupy 2a (0, 0, 0), 2a (0, 0, 0), 4d (0, 1/2, 1/4) and 4e (0, 0, 0.38261) position, respectively. The Curie temperature (Tc) of Nd_(0.7)Gd_(0.3)Mn_2Si_2 alloy is 42 K, while the spin reorientation temperature (T_(SR)) is 26 K and the Nel temperature (T_N) is 410 K. The Tc and T_N were determined using PPMS and DSC, respectively. The maximum value of the magnetic entropy change (-S_(max)) in the field change of 0-5 T is 11.862 J/kg K, while the value of relative cooling power (RCP) in Nd_(0.7)Gd_(0.3)Mn_2Si_2 alloy is 69.666 J/kg under the field change of 5 T.