Ion implantation and diffusion annealing methods were used to study surface Co diffusion in 5N-purity specimens at 110 to 300C. The results could be described by:

D (cm2/s) = 9.0 x 10-3 exp[-46.4(kJ/mol)/RT]

K.Kusunoki, S.Nishikawa: Scripta Metallurgica, 1978, 12[7], 615-6