Trends in rare earth permanent magnets

A brief description is given of trends in research and development of permanent magnet materials, these trends being dictated on the one hand by industrial needs, on the other hand by limitations of the physical and crystal chemical properties of the intermetallic phases concerned. Recent results are discussed of materials based on Nd/sub 2/Fe/sub 14/B, solid solutions of interstitial N and C atoms in Sm/sub 2/Fe/sub 17/, ThMn/sub 12/ type compounds and alloys consisting primarily of Fe/sub 3/B.<
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