How deep is the tool inserted into the material?

The depth of tool penetration is one of the main parameters of the FSW process to ensure the quality of the weld. For this purpose, it is necessary to carry out prototype tests in order to define the welding parameters as well as possible. One of these indicators is the force exerted (in kN) on which the penetration depth of the tool depends.
The penetration depth will depend on the force exerted during the welding operation but also on the thickness of the parts to be welded.
It is essential that the pin of the FSW tool penetrates the entire length of the workpiece. This ensures that the shoulder rubs against the workpiece and generates the heat required for mixing.
The penetration depth is the lowest point of the shoulder below the surface of the welded part. The depth must be correctly set to ensure the necessary downward pressure for the FSW tool to fully penetrate the welded joint.
A precise study will define the penetration depth of the FSW tool according to its application to ensure an optimal weld.