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Friction Stir Spot Joining

Friction stir spot joining is a form of solid-state joining where overlapping sheets are joined by a plunging tool. It produces high-strength spot joints without melting.

Physicochemical mechanism of action

The tool stirs the metal at the joint, causing local plastic deformation. This joins the sheets mechanically and forms a strong spot joint.

Metallurgical relevance & risks during welding

Insufficient stirring can lead to missing joints or weak points, while excessive stirring can damage the material and reduce strength. It is important to set the correct pressure and rotation speed of the tool.

Workshop practice & action instructions

Use a plunging tool of the right size for the material. Run it at a pressure of 100 to 200 N/cm² and a rotation speed of 500 to 1000 rpm. Make sure the sheets are clean and overlap well.

MetallurgieSchweißtechnik

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