Results of a quantitative analysis of fluorescence extended X-ray absorption fine structure are presented obtained at the Fe and Ni K absorption edges of a beta-NiAl sample microalloyed with iron. The concentration of Fe was 0.2 at.% substituting for Ni. The quantitative analysis results in a suggestion of a local structure model for the neighbourhood of Ni as well as of Fe atoms. Results show that Fe atoms at this low content do not occupy Ni sites in the B2 structure nor sites in clusters of alpha-Fe. They rather indicate that small clusters of Fe-Ni are formed which crystallize similar to either the Cu type or to the ordered phase FeNi3 in the Cu3Au type. [References: 26]
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