Hossein Eskandari

Friction stir processing (FSP) has attracted much interest to process ultrafine-grained Al alloys and Al-matrix nanocomposites. In the present study, multiple-pass overlapping FSP was employed to fabricate Al-metal matrix hybrid nanocomposites with addition of micro-sized and nano-sized TiB2 and Al2O3 ceramic particles through the AA8026 aluminum alloy. The microstructural features and mechanical properties of the nanocomposites were investigated. The type and combination of reinforcement nanoparticles were altered and the formation of nanocomposites with different characteristics was elaborated. Variations in the grain structure dependent on the composition and FSP pass number were also examined. Finally, the strengthening mechanisms were elaborated by dislocation models and microstructure-mechanical strength relationship was examined