Local cladding and alloying of advanced al alloys employing friction stir welding
In this research an advanced solid state cladding process, based on Friction Stir Welding (FSW) is researched. FSW is a relatively new solid-state joining technology for metals, see Figure 1. It shows no solidification-related joint imperfections which makes it utmost suitable for hard-to-weld highly alloyed aerospace aluminum grades, like AA 2xxx and 7xxx. The developed process during this research project is entitled Friction Surface Cladding, see Figure 2 for a configuration without a central probe. The FSC technology enables the deposition of a solid-state coating using filler material on a substrate with good metallurgical bonding.
Figure 1: Schematic representation of the friction stir welding process
Figure 2: Schematic representation of the friction surface cladding process (FSC)
The FSC technology has the following potential advantages:
- Protective coating against wear and corrosion (see Figure 3).
- Increase of the weld strength.
- Welding of geometries which require addition material.
- Filling of the end hole.
Figure 3: Cross section of an AA2024 cladded plate with an AA1050 coating.
Local cladding and alloying of advanced al alloys employing friction stir welding.