Diffusivity in amorphous and crystalline samples was measured, using evolution methods, at temperatures of between 300 and 600K. It was found that the diffusion coefficients of H and D in crystallized Pd80Si20 and Pd70Ni10Si20 alloys were some 1.5 to 2 times larger than those in the equivalent amorphous alloys (figures 31 and 32). In the case of Pd50Ni30Si20, the diffusion coefficients were the same for both amorphous and crystalline samples. In general, the activation energies for H and D diffusion increased with increasing Ni content. Also, the difference between the activation energies for H and D diffusion in the amorphous and crystalline samples usually decreased with increasing Ni content. The difference changed sign in the case of amorphous Pd50Ni30Si20.

Diffusivities of Hydrogen and Deuterium in Amorphous and Crystallized Pd-Si Based Alloys. Y.Takagi, K.Kawamura: Transactions of the Japan Institute of Metals, 1981, 22[10], 677-85

Figure 31

Diffusivity of D and H in Pd80Si20

(open squares: D in crystalline samples, filled squares: H in crystalline samples,

filled circles: D in amorphous samples, open circles: H in amorphous samples)