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In this investigation, special consideration was given to observe the influence of the acquired ultra-fine-grain (UFG) structure through friction stir processing (FSP) on mechanical and damping properties. As the mechanical behaviour of the composites are intensely related to their microstructure. For deeply understanding the possible mechanism and detailed microstructural observations at a longitudinal cross-section of friction stir processed pure aluminium and several composites reinforced with bare SiC, Al2O3 coated SiC and ZnAl2O4 coated SiC were investigated through EBSD analysis. The mechanical as well as thermal cyclic (from −100 to 400 C) damping performance of the friction stir processed composites were studied, respectively. Our first principles calculations show that the storage modulus of the resultant composite SiC/ZnAl2O4/Al was enhanced by a factor of ∼1.9 after FSP as compare to parent Al. The ultimate tensile strength (UTS) of the friction stir processed SiC/ZnAl2O4/Al composite was enhanced by a factor of 3.3 and the acquired microhardness was almost doubled as compare to parent FS processed pure aluminium mainly because of significant grain refinement according to Hall–Petch relationship. Finally, improved properties, attributable to stabilization, enhanced distribution of the tailored SiC particles, improved load transferring capacity and better interface bonding between encapsulated reinforcements and matrix of FS processed composites were obtained with potential application in aerospace and automobile industries. Keywords: Ultra fine grain (UFG), Electron back scattered diffraction (EBSD), Inverse pole figure (IPF), Internal friction/damping, Mechanical characterization