51Cr diffusion in α-Zr single crystals

Abstract

The volume diffusion coefficients of the fast-diffusing solute 51Cr have been obtained in oriented α-Zr single crystals, in the directions parallel and perpendicular to the c axis. The dependence of these diffusion coefficients on temperature was also measured between 750°C and 848°C.Single crystals were grown by thermal cycling through the α α β transformation temperature (862°C). Diffusion coefficients were measured using the “ thin film” method. In some experiments non-Gaussian penetration profiles were obtained and this behaviour is also analyzed.The diffusion of 51Cr is faster in the c axis direction, with Q∥(153 kj/mol) < Q⊥ (163 kj/mol). The anisotropy factor . This factor, the activation energies and frequency factors are discussed in comparison with those of other solutes.