Friction Stir Welding : Current State of the Art and Future Prospects

This paper focuses on Friction Stir Welding (FSW), a fairly recent technique, invented by The Welding Institute (TWI) in 1991, that utilizes a non-consumable rotating welding tool to generate frictional heat and plastic deformation at the welding location; thereby, affecting the formation of a joint while the material is in the solid state. In particular, FSW can be used to join high-strength aerospace aluminum alloys and other high temperature metallic alloys that are hard to weld by conventional fusion welding. FSW is considered to be the most significant development in metal joining in a decade. This work addresses the current state of understanding and development of the FSW process. The principles of weld formation, welding parameters, design principles, process speed and application areas of FSW for improved welding are discussed. Since FSW is a leap forward in manufacturing technology, some of the typical industrial applications of FSW in aerospace, shipbuilding and auto industries have also been presented.