Frictional heat between the rotating shoulder and the workpiece provides the required heat to join aluminum substrates.
The rotational pin motion creates a circulatory flow of plasticised material at the pin interface and generates enough deformation heat to form a weld nugget. The weld macro-shape depends of the pin shape. The rotation combined to the traverse movement of the pin subject the plasticized materials situated directly below the shoulder to extrusion mechanisms.
As the metal substrates do not melt and recast as such, internal porosities and solidification defects can be efficiently avoided.
Get Inside Metal Additive Manufacturing
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