Induced anisotropy in fine particles for magnetic recording

An automatic apparatus allows fast studies of magnetic annealing and thermal variations of coercive force and remanent magnetization in cobalt substituted gamma -Fe/sub 2/O/sub 3/ particles for magnetic recording. Experimental results are interpreted with Neel's model (1954) of directional order. The model and results permit an understanding of the origin of surface anisotropy of surface cobalt doped particles.<
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