Magnetic properties and magnetocaloric effect in Dy 1− xSc xNi 2 solid solutions

Abstract

X-ray diffraction, magnetization, magnetic susceptibility, and heat capacity data are reported for the solid solutions Dy 1− x Sc x Ni 2 (0 ≤ x ≥ 1). All the Dy 1− x Sc x Ni 2 solid solutions are single phase with the C15 cubic Laves phase superstructure. The alloys with x ≤ 0.8 are ferromagnets with a low (below 22 K) Curie temperature that decreases from 21.1 K for DyNi 2 to 4.5 K for Dy 0.2Sc 0.8Ni 2. Dy 0.1Sc 0.9Ni 2 and ScNi 2 have no long-range magnetic order down to 2 K. At high temperatures, all the Dy 1− x Sc x Ni 2 solid solutions, except ScNi 2, are Curie–Weiss paramagnets. The Debye temperature, phonon and conduction electron contributions as well as a magnetic contribution to the heat capacity have been determined from heat capacity measurements. The magnetocaloric effect for selected solid solutions was determined in magnetic fields up to 3 T.