Patent ID: 8225984

Claim:
A method of forming a weld joint between a first longitudinal element and a second longitudinal element where the first and second longitudinal elements are made of dissimilar materials, said method comprising the steps of: moving the first and second longitudinal elements longitudinally relative to a support assembly, said moving step including the step of abutting the first and second longitudinal elements along laterally opposed first and second facing edge surfaces of the dissimilar materials; plasticizing a continuous longitudinal interface between the opposed first and second facing edge surfaces of the dissimilar materials, said plasticizing step including the step of heating the opposed first and second facing edge surfaces of the dissimilar materials to a plasticizing temperature as the first and second longitudinal elements are longitudinally moved longitudinally relative to the support assembly; mixing, with an elongate mixing tool extending into the plasticized dissimilar materials of the first and second facing edge surfaces, the dissimilar plasticized materials of the first and second facing edge surfaces as the first and second longitudinal elements are moved relative to the support assembly whereby a longitudinal weld joint of the dissimilar materials of the opposed first and second facing edge surfaces is formed downstream from the mixing tool; and forging, with first and second containment forging elements provided on the support assembly downstream of the mixing tool and positioned on first and second sides of the first and second longitudinal elements, the first and second longitudinal elements as the first and second longitudinal elements are longitudinally moved between and relative to the forging elements, said forging step including the step of containing the moving first and second longitudinal elements during mixing of the dissimilar materials of the first and second facing edge surfaces by the mixing tool.