Friction stir welding of Al/Mg2Si metal matrix cast composite

in this research, friction stir weldability of 15 wt % Mg2Si particulate aluminum matrix cast composite and effects of tool rolation speed microstructure and mechanical properties of the joints were investigated. Microstuctural observations were carried out by employing optical and scanning electron mieroscopy of the cross sections perpendicular to the tool travrse direction. mechnaical properites inclding hardness existing in eutectic were evaluated in detail. the results showed fragmentation of Mg2Si paricles and MgSi needles existing in eutectic sturcture stir zone. also. homogeneous distribulion of Mg2Si particles was obseved in the stir zone as a result of strring with high plastic strains . tension test results indicated that tensile strength of the jonint had an opimium at 1120 rpm tool rotation speed. Hardness of the jonint increased due to modofication of solidification micostructure of the base composite, this research indicates that friction stir welding is a good candidate for joning of 15 wt % Mg2Si aluminum matrix composite castings.

Keywords:

fiction stir welding , metal matrix cast composite , mechanial properties , microstructure.