Iron self-diffusion in nanocomposite FeZr alloy was investigated using a neutron reflectometry technique as a function of applied compressive stress. A composite target of Fe+Zr and 57Fe+Zr was alternatively sputtered to deposit chemically homogeneous multilayer structure [natFe75Zr25∕57Fe75Zr25]10. The multi-layers were deposited onto a bent Si wafer using a three-point bending device. Post-deposition, the bending of the substrate was released which resulted in an applied compressive stress on to the multilayer. In the as-deposited state, the alloy multilayer forms an amorphous phase, which crystallizes into a nanocomposite phase when heated at 373K. Bragg peaks due to isotopic contrast were observed from chemically homogeneous multi-layers when measured by neutron reflectivity, while X-ray reflectivity showed a pattern corresponding to a single layer. Self-diffusion of Fe was measured with the decay of the intensities at the Bragg peaks in the neutron reflectivity pattern after thermal annealing at different temperatures. It was found that the self-diffusion of Fe slows down with an increase in the strength of applied compressive stress.

Iron Self-Diffusion in FeZr∕57FeZr Multilayers Measured by Neutron Reflectometry - Effect of Applied Compressive Stress. M.Gupta, A.Gupta, S.Chakravarty, R.Gupta, T.Gutberlet: Physical Review B, 2006, 74[10], 104203 (10pp)