FSW Process Principles
In FSW, a cylindrical shouldered tool with a profiled pin is rotated and plunged into the joint area between two pieces of sheet or plate material. The parts have to be securely clamped to prevent the joint faces from being forced apart. Frictional heat between the wear resistant welding tool and the workpieces causes the latter to soften without reaching melting point, allowing the tool to traverse along the welding line. The plasticized material, transferred to the trailing edge of the tool pin, is forged through intimate contact with the tool shoulder and pin profile. On cooling, a solid phase bond is created between the workpieces.
- Joining without melting
- No consumables
- Heat input due to friction between tool interface and material
- The rotating tool is forced against the workpiece.
- The plasticized material forms a homogeneous joint
FSW process Drawing courtesy of ©TWI