Manufacturing Technologies Inc have produced this video explaining the fundamentals of friction stir welding. A colleague of mine in the Aerospace industry directed me to this process as one that has allowed significant optimization in the aircraft manufacturing industry. As he explained to me the technology has been implemented in select areas aircraft manufacturing in lieu of painstaking process of riveting components together including some joints in the Airbus A380.
As MTI’s video explains the process of friction stir welding starts with a rotating pin tool that is plunged into the work pieces that are to be joined. This creates heat at the interface from the friction and the material on both parts softens. Axial pressure is applied until the tool reaches its shoulder in the material. The heat from the friction has now softened the material at the starting point and the tool can move along the seam that is to be joined.
As the tool moves material from both parts is swept from the leading edge to the trailing edge. Material is now left at the trailing edge and hardens as the friction stir weld tool moves away leaving the two pieces joined as one.
Unfortunately MTI’s video doesn’t show the start and finish of the complete loop and other videos I have seen for this process don’t show the weld starting and finishing at the same point. I will continue to scour the internet for a better video of the weld process being run in a complete loop.