Friction Stir Welding (FSW) is a solid-state joining process that uses a rotating, non-consumable tool to generate frictional heat and mechanically mix the materials at the joint line without melting.
- Benefits for Aluminum:
- High Strength: Joints often approach the strength of the base material, with excellent fatigue properties.
- No Melt-Related Defects: Avoids porosity, hot cracking, and distortion common in fusion welding of aluminum.
- Excellent for Extrusions: Ideal for joining long, straight seams (e.g., for making large panels from profiles).
- Environmentally Friendly: No fumes, spatter, or shielding gases required.
- Weldable Alloys: Can weld alloys considered “unweldable” by conventional means (e.g., 2xxx and 7xxx series).
It’s used in shipbuilding, aerospace (e.g., SpaceX rocket tanks), railcar manufacturing, and for creating large heat exchanger panels.