Correspondence: Grain boundaries in thin-film bicrystals of surface-reactive metals prepared by vacuum welding

Abstract

A technique was developed for preparing thin-film bicrystal specimens of surface-reactive metals containing grain boundaries of controlled geometry. Epitaxial films were deposited on oriented substrates and were then welded together face-to-face in situ under vacuum. Low-angle twist boundaries in copper and aluminium prepared by this technique contained grids of primary dislocations as shown by transmission electron microscopy. Grids of secondary grain boundary dislocations were detected in high-angle 〈111〉 twist boundaries at twist angles near the high coincidence density σ = 3 misorientation. The potential use of the technique in the study of interphase intefaces was pointed out.