Grain Boundary Diffusion and Segregation of Co and Cr in Zr-Based Alloys

摘要

~(51)Cr and ~(60)Co diffusion along grain boundary (GB) in polycrystalline α-Zr and β-Zr-20%Nb were measured by means of the radiotracer technique in an overall temperature range [380-1000] K. The use of Harrison's C and B kinetics resulted in direct data of the GB diffusivity (D_(gb)) and the apparent GB diffusivity (P_(gb)). The analyzed temperatures involved those of power reactors service. The GB segregation factors s were determined or evaluated in the limit of very dilute solute concentration.