Experimental determination of the switching field and its temperature dependence of isotropic polycrystalline hard magnets

The single particle switching field and its temperature dependence of an isotropic sintered NdFeB hard magnet are determined by a new method using both the perpendicular and the parallel component of the susceptibility related to the applied field. The results can be fitted by a simple 1/cos /spl thetav/ law for /spl Theta/<60/spl deg/, indicating an anisotropy field in the activation volume not too strongly reduced with respect to that of the /spl Phi/ phase Nd/sub 2/Fe/sub 14/B.<
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