Resolution of Cu Atoms in a GP[1] Zone in Al–Cu by FIM and Determination of the GP[1] Structure

Abstract

By FIM the atomic arrangement of a GP[1] zone in an aged Al–Cu alloy is resolved into isolated spots on the {024} planes. These resolved spots are identified as the images produced by individual Cu atoms of the GP[1] zone protruding on the {024} surfaces. By observing the position and shape formed by the spots corresponding to the Cu atoms during the successive field evaporation, it is concluded that a GP[1] zone consists of a single layer of Cu atoms on the {002} planes.