Experimental Investigations of Microstructure of Al 1100 Alloys Welded by Friction Stir Welding Process

Friction stir welding (FSW) is a relatively new solid-state joining process. This joining technique is energy efficient and environment friendly. In this paper, hardness and tensile properties of welded zone of aluminum 1100 alloys by friction stir welding process was investigated and the effects of rotational and traverse speeds of tool on these parameters were studied. According to the results of this research, the hardness of weld material is higher than the base material and is increased by decreasing the rate of rotational speed to traverse speed. Also the yield strength of the weld material is 70% of the base material in best condition due to the weak thermo mechanically affected zone around weld nugget. Although in some samples the tensile strength of the weld material is equal to the base material.