Influence of deformation microstructure on the precipitation behaviors of an Al-4Mg-0.3Cu alloy.

To provide insight into the effect of deformation microstructure on the precipitation behavior, an Al-4Mg-0.3Cu alloy was processed by high-pressure torsion followed by subsequent in-situ heating in a transmission electron microscope. Structural characterization revealed significant differences in the size, composition and spatial distribution of the precipitates in the alloy subjected to different strains. Different grain sizes led to various dislocation substructures and grain boundary volume fractions, which in turn governed precipitation behaviors. In addition, the composition of the precipitates along the grain boundaries varied with the grain size due to the change of the grain boundary volume fraction and diffusion behavior. [ABSTRACT FROM AUTHOR]