Sublimed fine-grained dysprosium: Significant magnetocaloric effect

As is known, rare-earth metals (REMs) are promising magnetocaloric materials. The magnitude of the magnetocaloric effect (MCE) of REMs significantly depends on their purity. This paper presents results of studies of the magnetic and magnetocaloric properties of sublimed dysprosium, prepared in the course of the present study, with an emphasis on its impurity and structure perfection. The comprehensive analysis of the chemical composition of sublimed dysprosium, which was performed for the first time by atom probe tomography, showed that the metal corresponds to high-purity rare-earth metals (3 N+). The MCE effect was studied using direct measurements of the adiabatic temperature change (ΔT_ad) in pulsed (up to 50 T) and steady (up to 14 T) magnetic fields. The studies of the MCE of polycrystalline sublimed Dy by direct method showed that the high ΔT_ad value for sublimed Dy are comparable with those obtained for single-crystal Dy in magnetic fields up to 5 T. The vacuum sublimation, which is more economical and technologically advanced in contrast to single crystal growing, can be used to create magnetocaloric REM-based materials with high MCE values.