Friction Stir Welding-What is it?

Friction stir welding was invented by Wayne Thomas at TWI in 1991, with patents filed in Europe, the USA, Japan and Australia. Further work to study the process was undertaken at TWI in 1992 with the project titled, ‘Development of the New Friction Stir Technique for Welding Aluminum.’ Industrial production using FSW was in progress by the mid-1990s, making it one of the shortest time periods for any welding process to go from invention to widespread use. The non-consumable tool, with a profiled probe and shoulder, is rotated and plunged into the interface between two work pieces. It then traverses along the joint line, causing the material to heat and soften. The shoulder also acts to contain this plasticized material, which is mechanically mixed to create a solid phase weld.