Phase relations in the system Sm-Fe-Ti and the consequences for the production of permanent magnets

Phase relations in the Fe-rich corner of the Sm-Fe-Ti system were investigated by means of microstructural examinations, EDX, and thermal and thermomagnetic analyses. Between 1000 degrees C and 800 degrees C, equilibria of Sm(Fe, Ti)/sub 12/ with the phases alpha -Fe, Fe/sub 2/Ti, and Sm(Fe, Ti)/sub 9/ were found, which are all ferromagnetic. The nonferromagnetic Sm(Fe, Ti)/sub 11/ is not in equilibrium with Sm(Fe, Ti)/sub 12/ because of the equilibrium Fe/sub 2/Ti+Sm(Fe, Ti)/sub 9/ (>or=900 degrees C) or Fe/sub 2/Ti+Sm/sub 2/(Fe, Ti)/sub 17/ (<900 degrees C). The Sm/sub 5/(Fe, Ti)/sub 17/ compound, having an extremely high anisotropy field, forms part of the stable system. It is in equilibrium with several ferromagnetic phases as well.<
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