Grain boundary films in Al–Zn alloys after high pressure torsion

In ultra-fine grained Al–Zn alloys after high pressure torsion Al/Al grain boundaries (GBs) completely, partially or pseudopartially wetted by Zn in the solid state have been observed using analytical and high resolution electron microscopy. In the latter case the solid Zn particles in the triple joints form a non-zero contact angle θ = 80–160° with Al/Al GBs. Simultaneously, a 2–10 nm thick uniform Zn-rich layer is present in the Al/Al GBs.