Measurements of Co diffusion in the a-phase were performed by using radio-tracer and direct sectioning techniques (table 141). The Arrhenius plot which was obtained was straight for temperatures ranging from 619 to 823K, and could be described by:

D (m2/s) = 3 x 10-6 exp[-127(kJ/mol)/RT]

The results agreed closely with previous data for temperatures ranging from 871 to 1135K, thus suggesting that there was no ultra-fast impurity effect for diffusion in the a-phase matrix.

R.A.Pérez, F.Dyment: Philosophical Magazine A, 1995, 71[5], 965-73

Table 141

Diffusion of 60Co in a-Ti