Relation Between High-Field Magnetization and Microstructure in Bulk SmCo $_2.5$ Cu $_2.5$

By varying the preparation, the microstructure of the rare-earth transition metal compound is modified. The samples were prepared by induction melting and, alternatively, by arc melting and at different annealing route afterwards. The occurring microstructure exhibits a phase separation within the hexagonal CaCu 5 -type structure. In a certain sample, a high-field transition was found. The temperature dependence of the transition field excludes the possibility of an itinerant electron metamagnetism. It could be shown that the microstructure is important for the field induced high-field transition