A Critical Review on the Development of Heat-Resistant Aluminum Alloys for Aerospace Applications

In recent years, the widespread adoption of Al alloys in the automotive and aerospace sectors can be attributed to their exceptional mechanical characteristics, lightweight, castability, and corrosion resistance. The enhancement of strength in commercial Al alloys is typically achieved through the formation of precipitates such as Al 2 CuMg, MgZn 2 , Mg 2 Si, and Al 2 Cu, employing the precipitation hardening mechanism. Despite these advantages, many Al alloys face limitations for high-temperature applications, as their strength diminishes above 200°C due to the coarsening and dissolution of precipitates at elevated temperatures. Research efforts in this domain predominantly concentrate on stabilizing phases and understanding their mechanical properties at room temperature. Some Al alloys, incorporating elements like Zr, Sc, and Ti, have demonstrated improved performance at higher temperatures, attributed to the formation of Al 3 M precipitates. Nevertheless, inconsistencies exist regarding alloy fractions, aging conditions, the operational temperature range, and high-temperature properties, thereby constraining the potential of these promising alloys.