Angular dependence of coercivity in Sm(Co, Fe, Cu, Zr)z magnets

Abstract The angular dependence of coercivity in a Sm(Co 0.75 F 0.12 Cu 0.10 Zr 0.03 ) 7.6 alloy is studied as a function of temperature in order to probe possible indications of a change in the reversal mechanism. The results show a gradual change of the magnetization reversal mechanism from pinning (at room temperature) to nucleation (at 500°C) with a mixture of both mechanisms co-existing in a large temperature range. The relatively weak angular dependence does not agree quantitatively with the degree of grain misalignment calculated by refinement of X-ray diffraction data. Possible explanations are discussed.