The present work concentrates on exploiting electron backscatter diffraction (EBSD) and transmission electron microscope (TEM) to investigate the effect of nano-SiC on the microstructure of Al-SiC composites fabricated by friction stir processing (FSP). With the introduction of nano-SiC, the average grain size and the proportion of low angle grain boundaries (LAGBs) decreased to 3.9 μm and 19.3 %, respectively, while the proportion of ∑3 and ∑9 grain boundaries increased slightly. The intensity of the main texture components in Al-SiC composite is reduced compared to FSPed Al. The Schmid factor of the Al-SiC composite decreased to 0.455, and the microhardness increased from 80.0 HV of FSPed Al to 100 HV. During the FSP process, the introduction of nano-SiC not only generates more randomly oriented grains in the composite, but also facilitates the occurrence of dynamic recrystallization.
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