Grain-boundary and interphase-boundary diffusion was investigated in the Ag/Ni system by using the radiotracer serial-sectioning technique. The Ni segregation in Ag grain boundaries was strongly temperature-dependent, and led to the conclusion that Ni atoms were located mainly in the bulk planes adjacent to the grain boundary. From interphase boundary-diffusion measurements in (110)-oriented Ag/Ni interphase boundaries, it was deduced that the structure of this interphase boundary was incoherent. The Arrhenius relationship for 63Ni grain boundary diffusion in Ag polycrystals was:

D (cm2/s) = 3.1 x 10-2 exp[-26.2(kcal/mol)/RT]

C.Minkwitz, C.Herzig, B.Straumal, W.Gust: Materials Science Forum, 1999, 294-296, 541-4