Integral corrosion protection of friction stir welded joints

摘要

A zone of corrosion-resistant material covering a friction stir welded joint surface is provided by applying a layer of corrosion-resistant material over one or both surfaces of the workpieces being joined so that the layer covers at least the weld zone which will be rendered plastic during a friction stir welding operation. The corrosion-resistant material layer is contacted by the friction stir welding tool, and the tool causes shearing and plastic flow of the corrosion-resistant material along the surface of the welded joint. The corrosion-resistant material thus metallurgically bonds with portions of the plasticized metal so as to form a corrosion-resistant zone protecting the welded joint from exposure to corrosive environments. IMAGE