Friction Stir Welded Aluminum Machining Preforms

The process of procuring large sections of aluminum plate or forgings for machined aircraft structures is often cost prohibitive and lead times are long. One way to minimize this problem is to construct a preform out of several smaller sections that is similar in size and shape to the end product. The challenges that arise from this method of creating aircraft parts from preforms include: joining the sections to create the preform, maintaining adequate material properties, and machining a part with close-tolerance features from a preform with multiple joints. Friction Stir Welding is a cost effective joining technique that can provide sufficient material properties for aircraft structural components. Remmele Engineering, Inc. (Remmele) will team with Lockheed Martin Aeronautics (Lockheed) to develop and demonstrate a method by which preforms can be constructed, thereby reducing the overall size (width, length, and thickness) of the raw material stock needed. The machining time as well as the lead time and cost of the stock plate or forging can be reduced significantly by constructing preforms.