Friction Stir Welding (FSW) of an Al-13%Si alloy matrix reinforced with 0, 3 and 6 wt% Al2O3 nanoparticles (nAl2O3) is performed and the optical microstructures, tensile strength, hardness and sliding wear properties of friction stir welded joints are investigated and compared to those of base materials. Four different zones of distinct appearances were observed during FSW, which exhibited altered microstructures in the nugget zone (NZ), thermo mechanically affected zone (TMAZ), heat affected zone (HAZ), and base material zone (BMZ). The ultimate tensile strength of the base materials and their welded joints were found to be increasing with increased wt% of nano-alumina reinforcements. High joint efficiency of 89-97% was achieved in FSW. Hardness and wear resistance of friction stir welded joints were found to be better than those of the base materials.
 W. Thomas, E. Nicholas, J. Needham, M. Murch, P. Temple-Smith, C. Dawes. Frictionstir butt welding, International patent application no. PCT/GB92/02203, 1991.
 W. M. Thomas, E. D. Nicholas. Friction stir welding for the transportation industries, Materials and Design, 1997 (18), 269 - 273.
 S.W. Kallee, J. Davenport, E. D. Nicholas. Railway manufacturers implement friction stir welding, Welding Journal, 2002 (81), 47 - 50.
 M. R. Johnsen. Friction stir welding takes off at Boeing, Welding Journal, 1999 (78), 35 - 39.
 L. Ceschini, I. Boromei, G. Minak, A. Morri, F. Tarterini. Effect of friction stir welding on microstructure, tensile and fatigue properties of the AA7005/10vol.% Al2O3p composite, Composites Science and Technology, 2007 (67), 605 - 615.
 H. Uzun. Friction stir welding of SiC particulate reinforced AA2124 Al alloy matrix composite, Materials and Design, 2007 (28), 1440 - 1446.
 A. H. N. Byung-Wook, C. H. O. I. Don-Hyun, K. I. M. Yong-Hwan, U.N.G. Seung-Booj. Fabrication of SiCp/AA5083 composite via friction stir welding, Transactions of Nonferrous Metals Society of China, 2012 (22), 634 - 638.
 X.-G. CHen, M. D. Silva, P. Gougeon, L. ST-Georges. Microstructure and mechanical properties of friction stir welded AA6063-B4C metal matrix composites, Materials Science and Engineering: A, 2009 (518), 174 - 184.
 S. J. Vijay, N. Murugan. Influence of tool pin profile on the metallurgical and mechanical properties of friction stir welded Al-10wt.% TiB2 metal matrix composite, Materials and Design, 2010 (31), 3585 - 3589.
 H. Nami, H. Adgi, M. Sharifitabar, H. Shamabadi. Microstructure and mechanical properties of friction stir welded Al/Mg2Si metal matrix cast composite. Materials and Design, 2011 (32), 976 - 983.
 S. Gopalakrishnan, N. Murugan. Prediction of tensile strength of friction stir welded aluminium matrix TiCp particulate reinforced composite, Materials and Design, 2011 (32), 462 - 467.
 I. Dinaharan, N. Murugan. Effect of friction stir welding on microstructure, mechanical and wear properties of AA6061/ZrB2 in situ cast composites, Materials Science and Engineering: A, 2012 (543), 257 - 266.
 A. Vieirae, M. Ferrante. Prediction of rheological behavior and segregation susceptibility of semi-solid aluminium-silicon alloys by a simple back extrusion test, Acta Materialia, 2005 (53), 5379 - 5386.
 M. O. Shabani, A. Mazahery. Application of finite element method for simulation of mechanical properties in A356 alloy, Int J Appl Math Mech, 2011 (7), 89 - 97.
 H. Ye. An overview of the development of Al-Si-alloy based material for engine applications, Journal of Materials Engineering and Performance, 2003 (12), 288 - 297.
 S. Yigezub, D. Venkateswarlu, M. M. Mahapatra, P. K. Jha, N. R. Mandal. On friction stir butt welding of Al+12Si/10wt% TiC in situ composite, Materials and Design, 2014 (54), 1019 - 1027.
 A. Handa, V. Chawla. Experimental evaluation of mechanical properties of friction welded dissimilar steels under varying axial pressures, Journal of Mechanical Engineering - Strojnícky časopis, 2016 (66), No. 1, 27 - 36.
 R. Jančo, L. Écsi, P. Élesztős. FSW numerical simulation of aluminium plates by Sysweld - Part I, Journal of Mechanical Engineering - Strojnícky časopis, 2016 (66), No. 1, 47 - 52.