The migration of H in undoped and B-doped samples was studied, at 588 to 1214K (table 16, figure 12), by monitoring the out-gassing of H-charged spheres. The diffusivity data were shown to fall into 2 groups which reflected the existence of a structural discontinuity at about 770K. In both cases, the H diffusivity obeyed the Arrhenius equation. The presence of 0.02at%B had no appreciable effect upon the H diffusivity. The latter was relatively high and, at 300K, approached that for H in body-centered cubic Fe at this temperature.

The Diffusion of Hydrogen in Ni3Al. Yang, L., McLellan, R.B.: Journal of the Physics and Chemistry of Solids, 1996, 57[2], 233-6

Figure 12

Diffusivity of H in Ni3Al