Thermal Stability of Lamellar Eutectic Structure in Fe-Ti Alloy

Fe-Ti합금계에서의 충상공정조직의 열적안정성

  • Wey, Myeong Yong (Dept. of Materials Engineering, Chungbuk National University) ;
  • Hasebe, Mitsuhiro (Dept. of Materials Science and Engineering, Kyushu Institute of Technology)
  • Published : 1997.06.30

Abstract

In order to elucidate thermal stability of Fe-$Fe_2Ti$ eutectic structure, the initial several structures have been investigated in the changes of coarsening and spheroidization during prolonged annealing under the eutectic temperature. The results are as follows: 1) The rate constant of coarsening and spheroidization was formulated as $S^{-n}-S_0^{-n}=k{\cdot}t$, where S is the total area of the interface between ${\alpha}$ and C($Fe_2Ti$) per unit volume, $S_0$ is initial value and k is the rate constant. 2) The coarsening and spheroidization mechanism was described by Ostwald ripening and controlled by diffusion of Ti-atom in ${\alpha}$-phase. 3) The spheroidization rate constant in eutectic lamellar structures was depended upon annealing temperature and showed the Arrhenius relation. The activation energy for spheroidization of lamellar structure was 365 kJ/mole.

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Acknowledgement

Supported by : 충북대학교