Influence of Tool Pin Profile and Welding Parameter on Tensile Strength of Magnesium Alloy AZ91 During FSW

AbstractMagnesium is flammable material and to avoid its limitation of fusion welding solid state welding process, called friction stir welding (FSW), is applied for joining two plates together. The friction stir welding uses a non-consumable tool for joining abutting plates of magnesium alloy AZ91 having 6mm thickness. FSW process joins the plates with advantages such as low distortion, no shielding gas required, and fine recrystallized microstructure. In Friction stir welding, process parameters such as welding speed, tool rotation speed, tool dimensions and axial force play an important role during welding. In the present work, the 6mm thick plates of the said alloy are joined at welding speed of 28mm/min to 56mm/min with tool rotation speed ranging from 710rpm to 1400rpm. Tensile testing was carried out to know the best parameter from the selected ones. Observations are also made for any defects by using fluorescent penetrant testing and photo micrographs