TIME-DOMAIN STUDY OF FE-57 DIFFUSION USING NUCLEAR FORWARD SCATTERINGOF SYNCHROTRON-RADIATION

Diffusion of Fe-57 in the intermetallic alloy Fe3Si was investigated u sing nuclear forward scattering of synchrotron radiation parallel to t he [113] crystal direction with the aim to demonstrate the feasibility of a diffusion study in a crystalline solid. The jumps between differ ent sites on a lattice, corresponding to a finite residence time on on e and the same lattice site, cause a loss of coherence of scattered sy nchrotron radiation. This gives rise to a decay of the forward scatter ed intensity which is faster than under static conditions. From the ti me dependence of the decay diffusivities of iron are derived.