Oxidation of φ'-aluminium oxynitride

cited By 4International audienceThe oxidation in air of single crystal φ'-aluminium oxynitride (AlON) grains has been characterized by thermogravimetry and X-ray diffraction in the 1273-1673. K range. Two oxidation stages have been observed, suggesting the formation of a transitional phase. Below 1473. K, oxidation results in the apparition of platelets and noodle-like crystals on the surface of the initially faceted single crystals. Above 1473. K, low density α-alumina polycrystals start forming on the grain surface and grow towards the grain core with increasing temperature or time. Their low density is mainly due to the presence of a network of nano-porosities. © 2010 Elsevier Ltd