Effect of alloying on activation energy of hydrogen diffusion in palladium alloys

The paper gives the results of experimental investigations and theoretical calculations of the activation energy of the process of hydrogen diffusion in palladium-based binary alloys. The anomalies of the temperature and concentration dependence of hydrogen diffusion in alloyed palladium are discussed. The theoretical analysis is made within the framework of the hardsphere model. The activation energy is estimated from the elastic deformation of atoms of the matrix and at the equilibrium and saddle points. An expression is derived for any activation energy from the concentration of the alloying elements as a function of the elastic moduli and the lattice constant of the alloy. The theoretical expression is compared with the experimental data.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 7–12, November, 1979.