Aluminum alloys (6XXX series) are widely used in the structural components of automotive and construction industries as they show a good combination of formability, corrosion resistance, weldability, and final mechanical properties. In this study two different welding processes have been considered: a conventional tungsten inert gas (TIG) and a relatively new solid state welding known as friction stir welding. Friction stir welding is carried out using automatic milling machine under five different welding speeds of (25-50-80-100-125 mm/min) and five different tool rotation speeds of...