Diffusion coefficients were measured in the α-phase of Fe-free binary Zr-(1 or 2.5)at%Nb alloys at 830 to 1100K. The diffusivity values for the 2 alloys were essentially indistinguishable and were little different to diffusion coefficients for Hf in Fe-free polycrystalline samples of α-Zr. The temperature dependence of the diffusivity in the alloys was characteristic of that in the bulk of intrinsic α-Zr:

D(m2/s) = 5 x 10-7exp[-2.7(eV)/kT]

H.Zou, G.M.Hood, J.A.Roy, R.J.Schultz, J.A.Jackman: Philosophical Magazine A, 1995, 71[4], 901-6