A study was made of T grain-boundary diffusion in the stainless steels, at temperatures ranging from -78 to 185C, by using direct measurements of T concentration profiles. The T was injected via transmutation of a surface blanket of 6LiF, the specimens were heated isothermally in order to establish a T diffusion gradient, and layers which contained the rapidly-diffusing grain-boundary component were removed by machining or electropolishing. The data were analyzed by using both the Fisher and Suzuoka models for grain-boundary diffusion, and similar diffusion parameters were obtained:

Fisher:     D (cm2/s) = exp[8.85] exp[-0.45(eV)/kT]

Suzuoka:    D (cm2/s) = exp[8.55] exp[-0.43(eV)/kT]

Grain Boundary Diffusion of Tritium in 304- and 316-Stainless Steels. R.D.Calder, T.S.Elleman, K.Verghese: Journal of Nuclear Materials, 1973, 46[1], 46-52