Computer simulations and irradiation in a 1000kV electron microscope were used to study radiation-induced solute segregation and point defect flow in typical austenitic alloys. The calculations involved the solution of the coupled rate equations for solute and defect concentrations, and consideration of the Kirkendall effect at a moving grain boundary sink. It was found that redistribution of Ni and Cr near to the grain boundaries, together with simultaneous grain boundary migration, occurred during irradiation. The degree of Ni enrichment at a grain boundary was especially marked, when compared with the degree of Cr depletion. It was suggested that grain boundary migration could contribute to flow of the under-sized Ni atoms towards the boundary.

S.Watanabe, N.Sakaguchi, N.Hashimoto, M.Nakamura, H.Takahashi, C.Namba, N.Q.Lam: Journal of Nuclear Materials, 1996, 232[2-3], 113-8