Friction Stir Welding (FSW) is a solid-state joining process, during which a constantly rotated tool with specially designed shoulder and pin is plunged into the work piece. Fictional heat is generated by friction between the tool and welding material, causing the stirred material thermo-plasticized. While the tool moves along the welding interface, plasticized material is swept from the leading edge of the tool and deposited at the trailing edge, thus realizing solid-state joining of work pieces after mechanical forging process by the tool.

Advantages: Stable and reliable welding, less deformation, products can work under high pressure (normal >2MPa, optimized >4MPa)