The lattice diffusion of 63Ni was studied, at 1070 to 1500K, by using serial sectioning and residual activity techniques. It was found that the lattice diffusion coefficients could be described by:

D (m2/s) = 8.62 x 10-5 exp[-255.9(kJ/mol)/RT]

Segregation and mass transport studies of the tracers along the grain boundaries were also carried out at 750 to 1080K. The grain boundary diffusion coefficients were obtained by using the Whipple and Suzuoka methods, and were found to be in good agreement. The grain boundary diffusivities could be described by:

D (m2/s) = 3.82 x 10-5 exp[-156.40(kJ/mol)/RT]

M.C.Naik, A.R.Paul, K.N.G.Kaimal, K.S.Venkateswarlu: Journal of Materials Science, 1990, 25[3], 1640-4

Table 170

Bulk Diffusion of Fe in Incoloy 800