Portable Friction Stir Welding Technology for Aluminum Fabrication

In Phase I, technical and commercial feasibilty has been demonstrated for low force FSW processes that could be implemented onto a flexible and portable robotic system. The processes were implemented on a standard industrial robot, which could be integrated into a portable FSW system for fabrication of aluminum modules for ship superstructure. Two approaches were demonstrated, including a low force standard FSW process for welding 5xxx alloys and a self-clamping, self-reacting process. In addition, potential designs were shown that could enable FSW to be used for various assembly operations, including assembly of modules. This would allow FSW to be used throughout the shipbuilding process and not just for panel fabrication, allowing the benefits of FSW to be realized throughout the assembly process. Phase II seeks to further develop the low force processes, by continuing research and develompment to optimize the processes. Production capable processes will be developed. In addition, hardware and software development will occur to allow integration of a flexible, but yet portable robotic FSW system capable of adapting to the variation that is inherent in ship construction. A complete system will be integrated to demonstrate the ability to fabricate wide panels, attach stiffeners and girders, attach corners, and assemble panels into modules. A typical module used on a Littoral Combat Ship will be fabricated for demonstration purposes.