A class of promising permanent-magnet materials with an appreciable high-temperature coercivity of 8.6 kOe at 500°C is reported. The Sm-Co-Cu-Ti magnets are prepared by arc melting and require a suitable heat treatment. Magnetization measurements as a function of temperature and x-ray diffraction patterns indicate that the samples are two-phase mixtures of 2:17 and 1:5 structures. Depending on heat treatment and composition, some of the magnets exhibit a positive temperature coefficient of coercivity. The promising high-temperature behavior of the coercivity is ascribed to the temperature dependence of the domain-wail energy, which affects the curvature of the walls and the pinning behavior.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)