CT-based detection of material flow in friction stir welding of dissimilar Al/Mg alloys with and without ultrasonic assistance
Tao Wang, Chuansong Wu, Lei Shi
Abstract
Comparative experiments of friction stir welding (FSW) of Al/Mg alloys were conducted with and without ultrasonic assistance. The copper powders were preset inside the workpieces as the marker material, and computer tomography technique was employed to obtain the three-dimensional information of material flow around the tool. The top view of copper powders distribution inside the weldments shows that the distribution zones of marker material at the retreating side and the trailing side were all widened by the exerted ultrasonic vibration (UV). The front view and side view of marker material distribution demonstrated that UV also enhanced the vertical material flow. Such detection results are helpful to elucidate the mechanism of ultrasonic-assisted FSW of dissimilar Al/Mg alloys.