Radiotracer and serial sectioning methods were used to study the diffusion of 63Ni in the boundaries of 4N8-purity material at 641 to 1324K. The results could be described by:

δD (m3/s) = 4.4 x 10-11 exp[-187(kJ/mol)/RT]

P.Neuhaus, C.Herzig: Zeitschrift für Metallkunde, 1988, 79[9], 595-9