Morphology of Oxide Scales on Ni3Al Exposed to High Temperature Air

Microscopic observations of oxide scale growth on Ni₃Al-based alloys are described to explain the effect of temperature on scale morphologies and the beneficial effect of 8% chromium on oxidation properties at 600 to 760°C. These observations are also used to examine the role of internal oxidation processes and remedial effects of chromium on the susceptibility of Ni₃Al to grain boundary embrittlement in air at 600 to 760°C.