INVESTIGADORES
DAMONTE Laura Cristina
artículos
Título:
NANOCRYSTALLINE HfN PRODUCED BY MECHANICAL
Autor/es:
M. A. BAB; L. A.MENDOZA-ZÉLIS; L. C. DAMONTE
Revista:
ACTA MATERIALIA
Editorial:
Elsevier
Referencias:
Año: 2001 vol. 49 p. 4205 - 4213
ISSN:
1359-6454
Resumen:
Nanocrystalline HfN powders were obtained by mechanically assisted gassolid reaction. An
analysis of the reaction kinetics under different milling frequencies and gas pressure is presented. The results
shown the formation of an interstitial solid solution a-Hf, prior to its transformation to cubic HfN. Rietveld
refinements of the X-ray diffraction data were done in order to analyze the progress of the structural change.
The short range order was characterized by perturbed angular correlations, which indicated a random distribution
of N around Hf. The reaction kinetics were obtained from the measured value of absorbed nitrogen
per Hf (n). Two main features were evident: the reaction advance dependence on the dose of mechanical
energy and a slowing down in the reaction kinetics for n0.5 associated with the saturation of surface sites.
These findings are discussed taking into account the structural change and the role of surface adsorption and
volume diffusion.a-Hf, prior to its transformation to cubic HfN. Rietveld
refinements of the X-ray diffraction data were done in order to analyze the progress of the structural change.
The short range order was characterized by perturbed angular correlations, which indicated a random distribution
of N around Hf. The reaction kinetics were obtained from the measured value of absorbed nitrogen
per Hf (n). Two main features were evident: the reaction advance dependence on the dose of mechanical
energy and a slowing down in the reaction kinetics for n0.5 associated with the saturation of surface sites.
These findings are discussed taking into account the structural change and the role of surface adsorption and
volume diffusion.n). Two main features were evident: the reaction advance dependence on the dose of mechanical
energy and a slowing down in the reaction kinetics for n0.5 associated with the saturation of surface sites.
These findings are discussed taking into account the structural change and the role of surface adsorption and
volume diffusion.n0.5 associated with the saturation of surface sites.
These findings are discussed taking into account the structural change and the role of surface adsorption and
volume diffusion.