Contribution a l'etude du systeme AL/O/N II: Retention d'azote dans les produits d'oxydation de l'oxynitrure d'aluminium γ

Abstract

This study confirms the retention phenomenon of nitrogen during the oxidation of γ aluminium oxynitride up to 1400°C. ESCA spectroscopy analysis of oxidised samples shows that the nitrogen is discharged during the reaction; its electronic state is nearly the same as that of atomic nitrogen. The structure of aluminium oxynitride and that of its oxidised product have been established by neutron diffraction. The γ Aluminium oxynitride phase presents an ideal spinel structure with disordered cationic vacancies in octahedral sites. Its oxidised product, so called γ′ alumina, also has a spinel structure with nitrogen atoms discharged in the anionic sites and cationic vacancies in the octahedral sites.