Mechanical properties and microstructural characteristics of friction stir welded AA2014-T6 aluminium alloy joints

The quality of friction stir welded joints depends upon the working parameters such as rotational speed, welding speed, shoulder diameter, tilt angle; etc. Each process parameter has a significant effect on the formation of joint strength. This investigation attempts to understand the effect of friction stir welding parameters on microstructural characteristics and tensile strength of AA2014-T6 aluminium alloy. This is performed by changing any one of the process parameters from minimum to maximum and keeping others constant. The joint fabricated from a rotational speed of 1500 rpm, welding speed of 40 mm/min, shoulder diameter of 6 mm and tilt angle of 1.5 degrees yielded superior tensile properties compared to their counter joints. Due to the formation of defect-free weld, balanced material flow and uniform distribution of strengthening precipitates in the stir zone is achieved.