Metallurgical Nature at the Interface between Tool Shoulder and Workpiece during Friction Stir Welding
Knowledge on the contact condition at the tool/workpiece interface is essential for understanding many aspects of FSW. In the present study, FSW experiments were conducted using aluminium alloys followed by metallographic examination focusing on the tool shoulder-workpiece interface region. It was observed that an interfacial intermetallic layer and hence metallurgical sticking/soldering readily formed. Temperature measurements have suggested the presence of interface liquid, hence suggesting a mechanical sliding contact condition dominant. This has been supported by the observation on material flow within the shear layer.
Deliang Zhang, Kim Pickering, Brian Gabbitas, Peng Cao, Alan Langdon, Rob Torrens and Johan Verbeek
Z. W. Chen et al., "Metallurgical Nature at the Interface between Tool Shoulder and Workpiece during Friction Stir Welding", Advanced Materials Research, Vols. 29-30, pp. 43-46, 2007