Oxidation behaviour of NiAl—II. Cavity formation beneath the oxide scale on NiAl of different stoichiometries

摘要: Abstract The formation of voids at the metal/oxide interface was observed after oxidation NiAl in temperature range 1173–1473 K. number and extent undermining scale increased with Ni content NiAl. growth to large cavities led loss adherence which fastest for Ni-rich materials. Calculations Al diffusion profiles were performed determine steady state surface concentration metal a cavity maximum evaporation rate Al. At high temperatures transport by is fast enough supply amount necessary growth. lower temperatures, e.g. 1173 K, insufficient during initial void may play role.