The kinetics of pore coalescence in ensembles located at grain boundaries in Cu and Cu-5at%Sn were studied by means of optical and scanning electron microscopy at 500 and 800C. In the case of pure Cu, the evolution of the pore ensemble obeyed a kinetic law which was typical of a grain-boundary diffusion-controlled process. In the case of the alloy, the kinetic law obeyed a relationship which was characteristic of a reaction-controlled process. The reaction in question was the generation of vacancies on the surfaces of the pores. The importance of surface reaction-controlled mass-transfer in alloys was considered. The grain-boundary self-diffusivity, and the kinetic coefficients of the reaction, were determined.

Evolution of Pore Ensembles Located at the Grain Boundaries in Cu and Cu-5at%Sn. Y.S.Kaganovskii, L.Paritzskaya, V.Bogdanov, M.Maslov, W.Gust, W.Lojkowski: Interface Science, 1998, 6[4], 299-305