Experimental investigation and computational study of atomic mobility in fcc ternary Co-Cr-W alloys

The interdiffusion coefficients in fcc Co-Cr-W alloys at 1373 K have been determined from the concentration profiles across the solid-solid diffusion couples using the Whittle and Green method. On the basis of the experimental interdiffusion coefficients in this work, together with the critically reviewed experimental diffusivities available in the literature, atomic mobilities of Co, Cr and W in fcc Co-Cr-W alloys were assessed as a function of temperature and composition by means of DICTRA (DIffusion Controlled TRAnsformation) software. Comprehensive comparisons between the calculated results and the experimental data indicate that the presently obtained atomic mobilities can reasonably reproduce most of the diffusivities, concentration profiles and diffusion paths in binary and ternary systems.