Highly Corrosion Resistant Aluminum Alloys: Innovative Processing Methods to Enhanced Corrosion Resistance (e.g., layered structures, etc.)

Two different approaches will be investigated for producing aluminum alloys with a layer structure that have mechanical properties similar to Al 7050-T7 and Al 7075-T6 and greatly improved corrosion resistance. Layered aluminum alloys will be produced using the Novelis-Fusion™ casting process. This process is very cost effective and has been demonstrate on commercial products. The other approach is to use the spray metal forming process to apply a corrosion resistant aluminum alloy to a high strength aluminum alloy. Microstructure analysis and mechanical property and corrosion tests will be performed to characterize the materials. It is anticipated that these processes will produce layer aluminum structures that have properties comparable to 7050-T7, with a 3x improvement in corrosion fatigue and alloys that have the mechanical properties of 7075-T6 and a stress corrosion cracking threshold stress >75% of the alloy’s yield strength.