The Effect of Tool Rotation Speed on the Formation of Eutectic Structure during Friction Stir Welding of Aluminum to Magnesium

Friction stir welding (FSW) is a solid-state process capable of joining wide range light metals. However, liquation and solidification may occur during dissimilar metals which leads to eutectic formation. This article aims discover the influence tool rotation speed on formation structure friction aluminum magnesium. To do so, was performed at 600 950 rpm join pure ECO-AZ91 magnesium alloy in lap configuration. In order investigate speed, speeds 23.5 37.5 mm/min were also chosen. Scanning electron microscopy (SEM) used study microstructure joints. A shear-tensile test evaluate joints’ strengths. The fracture surfaces studied by SEM. results revealed that changing directly affects formation, whereas had no influence. lower resulted thin, continuous intermetallic layer, higher led massive Mg-Al12Mg17 microstructure. eutectic, as an indicative liquation, affect material flow due decreasing coefficient between material. macrostructure analyses showed phase evolution well mechanism are highly affected liquation.