A least-squares computational method for fitting experimental diffusion data to the Whipple-Suzuoka equations for grain-boundary diffusion was described. The basic equations were extended so as to include diffusion within the grain boundary and make the method applicable to Harrison's type-B and/or type-C kinetics. The new method involved no new approximations or assumptions, and required input data for the grain-boundary half-width, the volume diffusivity and the annealing time. The fitting parameters were the half-distance between parallel grain boundaries, and the diffusivity in the grain boundary. Experimental diffusion profiles in polycrystals and bi-crystals were analyzed.

A least-squares method for fitting diffusion data D.Shaw, T.L.Shaw: Journal of Applied Physics, 1998, 84[7], 3586-92