An ODS Fe-Al intermetallic alloy has been nitrided at low-energy high flux implantation diffusion at 400 degreesC leading to the formation of hexagonal Al-N and alpha-Fe segregation. Its high temperature behaviour is subsequently evaluated under isothermal oxidation at 800 degreesC. Microscopy techniques (SEM, TEM) will show that nitridation hinders aluminium outward diffusion and enhances iron outward diffusion giving rise to a layered structure. (C) 2004 Elsevier B.V. All rights reserved.