Site occupation preference of fe in Ni₃Al: An atom-probe study

The substitution behaviour of Fe in Ni₃Al has been studied by atom-probe microanalysis for Fe concentrations from 0·4 to 1·9 at%. Effects of the matrix composition and annealing temperature have also been examined. Fe atoms have been found to occupy mostly Al sites, regardless of the Fe concentration and the matrix composition. The present observation and the experimental results for higher Fe levels reported in the literature are discussed in the light of the site preference predicted by various empirical rules and theories.