A review of creep-resistant aluminum alloys: Control of primary strengthening phases

Aluminum alloys have become critical lightweight materials in aerospace, defense equipment, and new energy vehicles due to their advantages such as low density and high specific strength. With equipment advancing toward high performance and integration, more stringent demands are imposed on the high-temperature creep resistance of aluminum alloy structural components. This review proposes optimization strategies for creep resistance based on the control of primary strengthening phases, systematically provides a comprehensive discussion of representative systems (Al-Cu, Al-Si, Al-RE, and AMCs) for different strengthening phases, incorporating perspectives such as processing techniques, microalloying, and multidimensional design. This review not only clarifies and substantiates the optimization strategies based on the control of strengthening phases, but also identifies a universal design principle: constructing strengthening phases featuring higher thermal stability, increased content, refined structure, and multi-level barriers. Ultimately, based on these strategies and principles, forward-looking research directions warranting further in-depth investigation for future extreme service conditions are presented. • The critical role of primary strengthening phases in high-temperature creep-resistant alloys is reviewed. • The creep-optimization strategies based on the control of primary strengthening phases are proposed. • The common design principles for creep-resistant aluminum alloys are summarized.