SELF AND SOLUTE DIFFUSION IN ZIRCONIUM. I. THE DIFFUSION OF $sup 60$Co IN $beta$ Zr.

The diffusion coefficient of 60Co in the b.c.c. β phase of 99.99% pure polycrystalline zirconium has been measured over the temperature range of 920 to 1700°c. The Arrhenius plot of log D versus 1/T shows some evidence of positive curvature above 1600°c but below that it is strictly linear and can be represented by: Anomalies in the concentration profiles were noted in experiments at temperatures below 1200°c. An account of their origin is suggested.