Self-Diffusion in Cobalt

Abstract

The self-diffusion of cobalt has been measured using radioactive ${\mathrm{Co}}^{60}$. The radioactive ${\mathrm{Co}}^{60}$ was evaporated onto the surface of pure cobalt samples. The absorption coefficient in cobalt of the complex spectrum of the radioactive isotope was required in the mathematical analysis used. This was determined under conditions similar to those present in the diffusion samples. The data at 1050°C, 1150°C, and 1250°C, indicate that the self-diffusion coefficient for cobalt is given approximately by $D=0.37\mathrm{}{e}^{-\frac{67000}{\mathrm{RT}}}$ ${\mathrm{cm}}^2$-${\sec }^{-1\mathrm{}}$.