Magnetocaloric effect of GdCo2−xAlx compounds

The structure, magnetic property and magnetocaloric effect of GdCo2−xAlx ( x = 0 , 0.06, 0.12, 0.18, 0.24, 0.4) compounds have been investigated by X-ray diffraction (XRD) and magnetic measurement techniques. The experimental results show that the GdCo2−xAlx ( x ≤ 0.4 ) compounds are single phase with a Laves-phase MgCu2-type structure. The Curie temperature T c initially increases, and then decreases with increasing Al content. The maximum value of T c , 418 K, is reached for the compound with x = 0.06 . The magnetic entropy change, which is determined from the temperature and field dependence of the magnetization by the Maxwell relation, decreases almost linearly with increasing Al content.