Friction Stir Welding (FSW) is a solid state joining process, meaning frictional heat is generated between the wear-resistant welding tool shoulder and pin, and the material of the work pieces. This heat, along with the heat generated by the mechanical mixing process and the adiabatic heat within the material, cause the stirred materials to soften without reaching the melting point (hence cited a solid-state process). This process is primarily used in industry for the production of long, straight welds in aluminum alloy plates, extruded aluminum profiles, and tailored blanks. Originally invented by The Welding Institute (TWI) in 1991, FSW has rapidly become known as a robust process which industries want to utilize due to its cost savings and improved performance.
