Friction Stir Welding
Friction stir welding is a solid-state joining process where a profiled tool plasticizes and joins the material through friction heat.
Physicochemical Mechanism of Action
A rotating profiling tool rubs over the surface of the material. The mechanical energy is converted into frictional heat that plasticizes the material. This plasticized state allows a strong bond between the joint surfaces through kneading.
Metallurgical Relevance & Welding Risks
The right choice of tool and speed is crucial for a homogeneous structure. Too high speeds can lead to uneven plasticization, which causes stress exhaustion and possible cracks. Too low speeds slow the process and can lead to an insufficient bond.
Workshop Practice & Instructions
Use a profiling tool with the right rotational speed to achieve even plasticization. The optimal speed normally lies between 50 and 100 m/min. Make sure the material surface is clean to produce a homogeneous bond.