Microstructure and magnetic properties in melt-spun and annealed Mn_(0.89)Cu_(0.11)CoGe ribbons

摘要

The melt-spun and annealed Mn_(0.89)Cu_(0.11)CoGe ribbons were prepared and the microstructure, magnetic and magnetocaloric properties in these ribbons were investigated. A single phase with the hexagonal Ni_2In-type structure was confirmed in both ribbons by XRD means at room temperature. A second-order magnetic transition was achieved for both ribbons, but the transition temperature had a slight decrease (~8 K) after annealing. The annealed ribbons present the antiferromagnetic exchange interaction and the spin-reorientation-like transition. A moderate magnetic entropy changes (AS) in the low magnetic field change were obtained for these ribbons, but a bit reduction of AS was revealed in annealed ribbons.