EBSD characterization of Al7075/graphene nanoplates/carbon nanotubes composites processed through post-deformation annealing

The effects of the post-deformation annealing on the microstructural evolution of hot rolled Al7075 matrix composites reinforced with CNTs and GNPs were investigated. The multi-pass hot rolling was applied on the stir cast samples. Annealing was then applied to the composites at 450 °C for 4 h. Microstructural evolution was examined by SEM, EDS, and EBSD techniques. EBSD data showed that the addition of 0.87 vol.% (GNPs + CNTs) significantly inhibited the occurrence of recrystallization. Also, in the composite with 0.96 vol.% CNTs, recrystallization was partially inhibited. Whereas, in composites with 0.92 vol.% of GNPs, the occurrence of recrystallization through particle stimulated nucleation (PSN) mechanism was significantly accelerated. The volume fraction of recrystallized grains depends significantly on the occurrence of PSN in the presence of reinforcements. The intensity and type of the main components of the texture as well as the FCC fibers depend on the type of reinforcement.