Magnetocaloric Effect of Alloys Gd(Al1 - x Cox)2

The magnetocaloric effect in alloys Gd(Al1 - xCox)2 with x = 0, 0.05, and 0.10 were investigated using X-ray diffraction (XRD) and magnetization measurements. It was found that three alloys crystallized in a single phase with MgCu2-type structure. The lattice parameter and Curie temperature decreased with increasing Co content, whereas the magnetic-entropy change increased. With a magnetic-field change of 2 T, the maximum of the magnetic-entropy change reached 4.6 J · kg−1 · K−1 near Curie temperature at approximately 95 K in the alloy GdAl1.8Co0.2, which appeared to be an alternative candidate for active magnetic refrigerants working in the temperature range centered at 100 K.