Diffusion of Iron, Cobalt, and Nickel in Single Crystals of Pure Copper

The rates of diffusion of radioactive tracers of Fe, Co, and Ni in single crystals of pure copper have been measured as a function of temperature from about 700 to 1075°C. The results, obtained by the tracer-sectioning technique, are as follows: $D_{\mathrm{Fe}\to \mathrm{Cu}}=1.4\mathrm{}\exp (-\frac{51 800}{\mathrm{RT}}); D_{\mathrm{Co}\to \mathrm{Cu}}=1.93\mathrm{}\exp (-\frac{54 100}{\mathrm{RT}}); D_{\mathrm{Ni}\to \mathrm{Cu}}=2.7\mathrm{}\exp (-\frac{56 500}{\mathrm{RT}});$ all in units of ${\mathrm{cm}}^2$/sec. An exploratory measurement for a Mn tracer in copper was made at 1069°C with the result $D=1.49\mathrm{}\times {10}^{-8\mathrm{}}$ ${\mathrm{cm}}^2$/sec.