In the present research, Al-Ni/Al 2 O 3 nanocomposite was in-situ synthesized by combination of Accumulative Roll-Bonding (ARB) and Friction Stir Processing (FSP). To do this, first Accumlative Roll-Bonding (ARB) was utilized to get Al/Ni/NiO composite. Therefor, five cycles of ARB were performed on aluminum sheets and nickel foils (15 wt%) containing a uniform dispersion of nickel oxide powders (1 wt%) on them. In the second part of the research, three passes of friction stir processing (FSP) with a linear speed of 12.5 mm/min and a rotational speed of 2000 rpm were performed on the Al/Ni/NiO composite. FSP was intended to fabricate Al-Ni/Al 2 O 3 nanocomposite through in-situ reactions between Al, Ni and NiO. As a comparison, Al-Al 3 Ni composite was produced under same conditions in the absence of oxide powder. Identification of the phases was done by x-ray diffraction (XRD) and energy dispersive spectroscopy (EDS). Microstructural features of the specimens were studied by scanning electron microscope (SEM) and optical microscope (OM). No intermetallic compound was found in the XRD patterns of the specimens after five cycles of ARB. On the other hand, FSP was successful in the formation of Al 3 Ni compound through in-situ reaction of Ni particles with Al matrix. Hardness values of the ARB samples were higher than the annealed aluminum sample and still lower than Al/Al 3 Ni-Al 2 O 3 and Al/Al 3 Ni composites. A significant improvement in the wear performance of the FSP samples compared to ARB samples, was observed. Due to the results of the tensile tests, the in-situ synthesized nanocomposites yield higher strength than ARB samples. Keywords: Alumium Matrix Nanocomposite, Nickel Aluminaids, Accumulative Roll-Bonding, Friction Stir Processing
