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Effects of thermal forcing on morphology of disordered binary metallic alloys: local equilibration and modification of near-surface elemental composition
Y. W. Kim and R. P. Cress

Thermophysical properties of disordered metallic alloy specimens have been found to evolve in time under thermal forcing. Two characteristic features underlying the evolution are: local equilibration of constituent elements within nano-crystallites; and enrichment of the more mobile atoms near alloy surfaces. We present an experimental examination of the roles played by the specific modes of thermal forcing, i.e., radiant versus Ohmic heating, in modifying the morphology of 80 W%Ni-20 W%Cr Nichrome specimens. Alloy modeling in terms of the size distribution of nano-crystallites is discussed. We also present findings from an experiment that simulates the heating of a disordered binary alloy as a randomly close-packed (RCP) bed of spheres at two diameters.

Keywords: Thermal forcing; disordered binary alloy; random close packing; thermal diffusivity; nichrome alloy; modeling by simulation of heating.

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