Aluminum-Lithium Alloys for Aerospace Applications Workshop

Aluminum-Lithium (Al-Li) alloys are the new generation of lightweight, high modulus alloys some of which also have high strength and high fracure toughness. These alloys offer high strength-to-weight ratios which make them attractive for aerospace applications. The purpose of the workshop was to disseminate to the propulsion community results emerging from government laboratories, industry and universities actively engaged in research, development and testing of Al-Li alloys. In all, 32 papers were presented and discussed, covering a wide range of topics: Al-Li alloy development, processing, physical metallurgy, analytical techniques, mechanical properties, corrosion and stress corrosion cracking, texture and anisotropy, fracture toughness, welding and joining, and forming. Most of the workshop focused on the latest generation of Al-Li alloys, i.e., the high strength, Weldalite family of alloys, such as 2195 alloy that has been selected for fabricating the super lightweight external tank of the Space Shuttle. Presentations illustrated that 2195 alloy has good corrosion resistance, excellent fatigue properties, can be near net shape formed and, with proper precautions, can be adequately welded. However, further research is needed to optimize processing to ensure required combination of strength and toughness in the final product.