The diffusion of Ni was measured by using radiotracers and precision grinding.

It was found that Ni exhibited fast-diffusion behavior, in that its diffusivity was 4 orders of magnitude higher than that of Ti. The diffusion data could be described by:

D (m2/s) = 1.76 x 10-5 exp[-195(kJ/mol)/RT]

The high mobility of these solutes, which had relatively small atomic radii, suggested that some type of interstitial diffusion was occurring.

J.Breuer, T.Wilger, M.Friesel, C.Herzig: Intermetallics, 1999, 7[3-4], 381-8