Recent developments in the weldability of lithium-containing aluminium alloys

The weldability of aluminum-lithium alloys is reviewed, with emphasis on alloys that are being commercialized: 2090, 8090 and Weldalite 049. These alloys are weldable, although hot-cracking susceptibility has been reported for 2090 and 8090 when welded with certain conventional filler alloys. Mechanical property data from weldments made by several techniques are emphasized. Weld-zone porosity problems have largely been controlled by proper weld-pretreatment and gas shielding. Interest in the weldability of aluminum-lithium alloys has taken on increased significance because of their potential to reduce the weight of space launch systems, whose fabrication most often involves welding. (Author)