Journal of Materials Science

, Volume 29, Issue 3, pp 652–659 | Cite as

Experimental and theoretical studies on phase separations in the Fe-Al-Co ordering alloy system

  • T. Kozakai
  • T. Miyazaki


Phase separations in iron-rich Fe-Al-Co ternary alloys were investigated by means of transmission electron microscopy, differential thermal analysis and magnetization measurement. Two kinds of phase separations have been found at 923 K; A2+B2 and B2+B2*. The former occurs in a tongue-shaped composition region ranging from Fe-12 at % Al-15 at % Co to Fe-35 at % Al-45 at % Co and the latter appears in the small region bordering on the Fe-Al binary side of the A2+B2 field. These two-phase fields have theoretically been evaluated on the basis of the so-called Bragg-Williams-Gorsky model taking account of not only chemical but also magnetic interactions. The magnetic ordering accounts for the expansion of the A2+B2 coexistent region. In the measurement of magnetic properties, large increases in coercive force, Hc, and residual magnetic flux density, Br, were observed in the two-phase microstructures.


Microstructure Transmission Electron Microscopy Magnetic Property Thermal Analysis Phase Separation 
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Copyright information

© Chapman & Hall 1994

Authors and Affiliations

  • T. Kozakai
    • 1
  • T. Miyazaki
    • 1
    • 2
  1. 1.Centre for Cooperative ResearchNagoya Institute of TechnologyNagoyaJapan
  2. 2.Department of Materials Science and EngineeringNagoya Institute of TechnologyNagoyaJapan

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