FE-57 AND SN-119 MOSSBAUER SPECTROMETRY STUDIES ON NANOCRYSTALLINE FE-SN SOLID-SOLUTIONS

Fe1-xSnx (0.04 less than or equal to x less than or equal to 0.124) so lid solutions with nanometer-sized grains were prepared by mechanical alloying. Broad spectral components are ascribed to Fe and Sn atoms at grain boundaries (GB) of the as-milled materials. The mean hyperfine fields at the nuclei of atoms at GB are smaller than they are for atom s in grains. By measuring the grain size and the fraction of atoms ato ms at grain boundaries, the effective thicknesses of the grain boundar ies could be estimated to be similar to 1 nm. Previously-reported Moss bauer spectra of Sn-119 atoms at GB of coarse-grained iron are discuss ed.