The surface diffusion coefficients were deduced from measurements of the neck size and neck curvature during the sintering of two spheres. The spheres were machined from single crystals. It was found that the results could be described by:

D (m3/s) = 0.015 exp[-518.7(kJ/mol)/RT]

P.Sajgalik, Z.Panek, M.Uhrik: Journal of Materials Science, 1987, 22[12], 4460-4