SHORT-RANGE ORDER IN BETA-NIAL MICROALLOYED WITH IRON

Results of a quantitative analysis of fluorescence extended X-ray abso rption fine structure are presented obtained at the Fe and Ni K absorp tion edges of a beta-NiAl sample microalloyed with iron. The concentra tion of Fe was 0.2 at.% substituting for Ni. The quantitative analysis results in a suggestion of a local structure model for the neighbourh ood of Ni as well as of Fe atoms. Results show that Fe atoms at this l ow content do not occupy Ni sites in the B2 structure nor sites in clu sters of alpha-Fe. They rather indicate that small clusters of Fe-Ni a re formed which crystallize similar to either the Cu type or to the or dered phase FeNi3 in the Cu3Au type.