Evolution of grain boundary structure in submicrometer-grained Al-Mg alloy

This paper presents high-resolution electron microscopy studies of grain boundary structures in a submicrometer-grained Al-3%Mg solid solution alloy produced by an intense plastic straining technique. The studies include the effect of static annealing on the grain boundary structure. Many grain boundaries are in a high-energy nonequilibrium state in the as-strained sample. The nonequilibrium character is retained on some grain boundaries in samples annealed at temperatures below the onset of significant grain growth. The effect of electron irradiation on the grain boundary structure also is examined.