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Role of alloying elements in phase decomposition in alnico magnet alloys


Partition of alloying elements between the Fe-rich disordered a, and NiAl-rich ordered α2 phases in Fe-Ni-Al base systems has been studied by the diffusion couple technique. It has been revealed that Ti, Cu, Mn, and Co are distributed to the α2 phase rather than the α1 phase, while Si, V, Nb, Cr, and Mo are mostly distributed to the α1 phase. Ti remarkably narrows the miscibility gap between the α1 and α2 phases and shifts the summit point to the Fe-rich side. Cu promotes the diffusion rate of atoms in the α2 phase. On the basis of these experimental results, the role of alloying elements in the spinodal decomposition of Alnico magnets has been discussed.

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Hao, S.M., Ishida, K. & Nishizawa, T. Role of alloying elements in phase decomposition in alnico magnet alloys. Metall Mater Trans A 16, 179–185 (1985).

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  • Metallurgical Transaction
  • Diffusion Couple
  • Spinodal Decomposition
  • Magnet Alloy
  • Easy Magnetic Axis