Grain boundary engineering process for nano reinforced aluminum matrix composites

It is challenging to obtain a balance of strength and ductility for alloys and their composites. They are expected to exhibit good comprehensive properties by adjusting the grain boundary character and/or in-troducing twin structures. However, for coarse grained aluminum with high stacking fault energies, twin structures are rarely found. In this study, a grain boundary engineering process was carried out on coarse grained aluminum containing nano-reinforcements via an alternated compression deformation, followed by an annealing treatment. The effects of the thermo-mechanical process and alloy elements on the mi-crostructures of the composites were analyzed. The mechanical properties and inter-granular corrosion properties of the composites were evaluated. Twin structures could be generated in these alloys. After thermo-mechanical process, the composites exhibited good plasticity as well as higher strength. A E3 twin boundary hindered inter-granular corrosion crack propagation. The formation mechanism of the twin structures and the strengthening mechanism are discussed.(c) 2023 Elsevier B.V. All rights reserved.

Automated summary

This study performed a grain boundary engineering process on coarse grained aluminum with nano-reinforcements through alternated compression deformation and annealing treatment. The effects of thermo-mechanical process and alloy elements on the microstructures were analyzed, and the mechanical properties and inter-granular corrosion properties were evaluated. Twin structures could be generated in these alloys, resulting in improved plasticity and higher strength. The formation mechanism of the twin structures and the strengthening mechanism are discussed.