Effects of Aging Temperature on Microstructure and Mechanical Properties of an Al-Cu-Li-Mg-Ag Alloy

Abstract

The third generation of aluminum alloy demonstrates considerable potential for advancement in the aerospace industry, primarily due to its outstanding mechanical properties. However, the inclusion of additional elements and the application of diverse heat treatment processes result in a complex precipitation sequence. This study investigates the microstructural evolutions of 2195 aluminum alloy, a third-generation Al-Li alloy, aged under different temperatures. The mechanical properties were elucidated in relation to the microstructural features. The evolution and interactions of composite precipitates such as δ’/θ’/δ’ and δ’/GPI/δ’ with other strengthening phases were observed. Ultimately, the precipitation sequence of the Al-Cu-Li-Mg-Ag alloy at different temperatures was discussed.

Keywords: Al-Cu-Li-Mg-Ag alloy, precipitation sequence, hardness evolution, aging temperature