Experimental studies were made of the effect of grain boundary Cu diffusion fluxes upon the creep behavior of coarse-grained or sub-microcrystalline Ni. It was found that, for both grain sizes, the creep rate was accelerated by the diffusional fluxes of Cu in the grain boundaries. This effect occurred within a lower temperature range in the case of finer-grained material. The Cu grain boundary diffusion coefficients in sub-crystalline material were measured experimentally at temperatures of 423 and 573K. A grain size dependence of the creep acceleration behavior was attributed to a higher diffusivity in the finer-grained material.

J.R.Kolobov, G.P.Grabovetskaya, I.V.Ratochka, E.V.Kabanova, E.V.Naidenkin, T.C.Lowe: Annales de Chimie, 1996, 21[6-7], 483-91