Portable Friction Stir Welding Technology for Aluminum Fabrication

This program is designed to development and implement portable friction stir welding for both repair and subassembly of Navy Al structures. This dual use requirement necessitates two different approaches. For example, subassembly implies relatively small structures and a moderate number of components. Further, subassemblies can be welded remote from their final assembly location and moved to, and final assembled, into the ship. A simple low-cost approach will be considered. Conversely, repair, by its nature implies at times one-offs, a multitude of geometries, and welding at a variety of locations. Access to the repair site and the ability to track a variety of paths requires a more versatile design. Components of the two systems can be the same and indeed interchangeable. However, the cost for a dedicated subassembly FSW system would be much less than that for a versatile repair system. Therefore, for eventual acquisition cost considerations, we are proposing to provide conceptual designs for both approaches. Further, studies will be completed to establish tool designs and weld parameters to minimize loads on the system. Program goals will be to make these systems robust, but lightweight and portable, and in the case of the repair FSW system, as versatile as possible.