The Phase Evolution, Microstructure, and Magnetocaloric Behavior of Gd100−xSnx Alloys (x = 5, 10, 15 and 20 At Pct) Alloys

This work examines the structure, microstructure, and magnetocaloric effect of binary Gd 100− x Sn x alloys ( x = 5, 10, 15, and 20). The X-ray diffraction (XRD), Mössbauer spectroscopy, and scanning electron microscopy (SEM/EDX) analyses confirmed a biphasic structure built by Gd(Sn) and Gd 5 Sn 4 phases. Magnetization (M) vs temperature (T) curves revealed changes in the Curie point of the identified phases. The temperature dependence of magnetic entropy change revealed one minimum for the Gd 95 Sn 5 , Gd 85 Sn 15 , and Gd 80 Sn 20 alloys; two maxima were detected for the Gd 90 Sn 10 alloy. The analysis of the exponent n from the phenomenological relation of the maximum value of magnetic entropy change ΔS Mmax vs magnetic field μ 0Hmax (ΔS Mmax = C( μ 0 H max ) n , C is a temperature-dependent constant) confirmed the biphasic structure of the Gd 90 Sn 10 alloy sample.