Kawasaki Heavy Industries and its subsidiary Kawasaki Shipbuilding Corporation (hereafter referred to collectively as Kawasaki) recently succeeded in perfecting friction stir welding (FSW) technology for heavy type 5083 aluminum alloy plates, the first company in Japan to do so. FSW is a revolutionary welding technique patented by The Welding Institute (TWI) in Cambridge, England. FSW can be used to weld alloys together, or to wrought products, in such a way that they are stronger, lighter and more efficient.
Kawasaki introduced FSW techniques from TWI in the late 1990s and began developing its own welding equipment and working parameters (revolutions and speed) for use with a variety of alloys, with an eye to applying the technology to its own products. This past August, the company succeeded in welding the type 5083 plates with a maximum thickness of up to 50mm. The alloy, which is the strongest of the nonheat-treated alloys, possesses excellent seawater corrosion resistance and lowtemperature properties. Kawasaki Heavy Industries Ltd
Kawasaki's breakthrough paves the way for a wider range of FSW applications, particularly in the shipbuilding industry. The company plans to use the technology not only in the cargo tanks of LNG carriers, but also in the construction of new marine vessels, including Kawasaki's ultrahigh-speed Jet Foil passenger craft and Jet Piercer car ferry.
