Binding energy of self-interstitial atoms to grain boundaries: An experimental approach

• An experimental approach for measuring energy of interstitials at grain boundaries is elaborated.
• A broad energy spectrum for interstitials at grain boundaries in W is revealed.
• No preferential grain boundary diffusion of interstitials was revealed in radiation experiments.

The energies of formation and binding of self-interstitial atoms at grain boundaries in tungsten have been found out using the field evaporation phenomenon. The binding-energy distribution for interstitials at the high-angle GB of general type is characterized by a broad characteristic energy spectrum energy spectrum with a full width at half maximum of 1.98 eV. Our experimental results are compared with published theoretical data on the interaction of interstitials with grain boundaries and found to be qualitatively reliable.