Effect of Friction Stir Welding Parameters on Mechanical Properties and Microstructure of AA2195 Al–Li Alloy Welds

In this paper, effect of friction stir welding process parameters on mechanical properties and microstructure of AA2195 welds were studied. Five levels of tool rotation speed from 400 to 1000 rpm and three levels of travel speed from 100 to 300 mm/min were considered. These parameters affected heat input generation in the welds, thereby influencing stir zone geometry, grain size evolution in stir zone, tensile properties and hardness of the weld. Low tool rotation speed and high travel speed resulted in finer grain size. Travel speed significantly affected the tensile properties compared to rotation speed. Processing window to achieve defect-free welds was identified, and maximum weld efficiency was obtained at 400 rpm rotation speed and 300 mm/min travel speed.