Influence of Friction Stir Welding Parameters on Mechanical and Metallurgical Properties in Lap Joints of 5456Aluminum Alloy

The research is based on experimental tests, lap joint welding of 5456 aluminum alloy was carried, so that the hard working H321 sheet with the thickness of 5 mm was placed on an annealed sheet with the thickness of 2.5 mm and has been investigating the simultaneous effects of parameters such as rotation speed and welding speed on metallurgical and mechanical properties in friction stir welding process. The results showed that increasing of rotation speed and reducing of welding speed (increase of welding step) causes increased heat input, increase vertical flux, increase hook height and reduction in effective Sheet thickness and it is causing the failure from the thermomechanical zone where the maximum heat input applied also, increasing of welding speed causes reduction in the material mixing and hook height and it causes an interface failure. It was observed with an examination of the results due to the differences in thickness of the sheets, existence of hook defect and its appropriate height and orientation is useful in this joint and causes an increase in strength and failure was in the base metal of the sheet with a thickness 2.5 mm in a tensile test.