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 data were described by:

D(m3/s) = 3.7 x 10-14exp[-90(kJ/mol)/RT]

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