THE DIFFUSION OF HYDROGEN AT LOW-TEMPERATURES IN PD-ER-H TERNARY SOLUTIONS

An electrolytic technique has been used to measure the temperature var iation of the diffusivity of hydrogen in Pd-Er solid solutions contain ing up to 8 at.% Er. The diffusivities were measured in the temperatur e range 270-340 K. The diffusion data for a given Pd-Er binary solvent conform to the Arrhenius representation. However the apparent activat ion energies Q(a) exhibit a non-linear variation with Er content. The Q(a) values show an initial increase with Er content and then a decrea se after a maximum at approximately 5 at. % Er. This behavior has been interpreted in terms of a statistical model based upon classical jump theory.