Published online by Cambridge University Press: 22 February 2011
The effect of Y and Zr on the oxidation behaviour of NiAl has been investigated using high resolution SIMS and analytical TEM. 18O tracer experiments in conjunction with SIMS showed that Y and Zr reduce the outward transport of cations during the growth of the AI2O3 scale. Complementary STEM-EDS measurements revealed segregation of Y and Zr at the metal/oxide interface as well as the grain boundaries in the AI2O3 scale. The amounts of segregation at both the interface and grain boundary were calculated to be less than one monolayer.