he objective of this work was to investigate the mechanical and metallurgical properties in order to demonstrate the feasibility of friction stir welding for joining A16061 and A16063 aluminum alloys Welding was performed on cylindrical parts with different thickness 2mm and 3mm, five rotational speeds,485,710,910,1120 and 1400 rpm and a traverse speed 4mm/min was applied. The tests were conducted for the study to determine the mechanical properties (maximum stress - the percentage of elongation) and hardness measurement along the welded sections using the Vickers method, was also studying the crystalline structure of welded joints .The FSW welds exhibited many advantages over traditional arc welding techniques.