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Electron-Optical Observations on the agr-Transformation in Troilite
Science (New York, N.Y.)
|November 1, 1974
Summary
The transformation from high to low troilite involves a continuous change to a transitional structure, followed by a discontinuous change to the low-temperature form, illustrating metastable behavior.
Area of Science:
- Mineral Physics
- Geochemistry
- Materials Science
Background:
- Troilite (FeS) exhibits phase transformations relevant to geological and materials science.
- Understanding these transformations is key to interpreting mineral behavior under varying conditions.
Purpose of the Study:
- To elucidate the mechanism of the high-to-low troilite transformation.
- To characterize the nature of the intermediate phase and its formation pathway.
Main Methods:
- High-resolution microscopy and diffraction techniques were employed.
- Thermodynamic and kinetic analyses were performed.
Main Results:
- The transformation proceeds through a distinct transitional structure.
- The transition to the intermediate state is continuous, while the final transformation to the low-temperature phase is discontinuous.
- This pathway highlights the potential for impeded nucleation of the low-temperature phase.
Conclusions:
- Troilite exhibits complex phase behavior, including continuous and discontinuous transformations.
- Metastable states are achievable in the troilite system due to nucleation barriers.
- The findings provide insights into the behavior of iron sulfides in diverse environments.
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