Hydrogen-Induced Enhancement of Interdiffusion in Cu-Ni Diffusion Couples

Abstract

Drastic enhancements of the interdiffusion were observed in Cu-Ni diffusion couples when samples were heated under high hydrogen pressures $(\ensuremath{\sim}5\mathrm{GPa})$. Interdiffusion coefficients measured between $600--800\ifmmode^\circ\else\textdegree\fi{}\mathrm{C}$ were increased by $\ensuremath{\sim}{10}^{4}$ times on the Ni-rich end and by $\ensuremath{\sim}10$ times on the Cu-rich end. The observation is explained in terms of superabundant vacancy formation in the presence of interstitial hydrogen atoms.