An experimental method was described for the separation of the effects of the various grain boundaries that were present in a sample, and for the effect of segregation upon grain boundary diffusion profiles. It was shown that, in the case of Ag diffusion in pure Cu, curved penetration plots were due to segregation effects. For pure Cu, the resultant activation energy and pre-exponential factor of the triple-product were 90kJ/mol and 3.7 x 10-14m3/s, respectively. In the case of the Cu-Ag alloy, the equivalent values were 119.4kJ/mol and 2.1 x 10-12m3/s, respectively. The activation energy for grain boundary segregation was estimated to be 37kJ/mol.

J.Bernardini, Z.Tökei, D.L.Beke: Philosophical Magazine A, 1996, 73[1], 237-47