Magnetic-resonance study of the transformationγ−Fe2O3→α−Fe2O3
- 1 July 1980
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review B
- Vol. 22 (1), 304-307
- https://doi.org/10.1103/physrevb.22.304
Abstract
The transformation has been investigated by magnetic resonance. The residual fraction of was measured for several aging times and temperatures, in the range 450-550°C. The experimental data show that the transformation can be described by a first-order kinetic equation and that the activation energy is 47 kcal/mol. This value is found to be independent of aging temperature and particle size. The results suggest that the reaction is growth controlled and that nucleation occurs preferentially at the particle surface.
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