Microstructure manipulation and high-temperature service performance enhancement of nickel-based superalloys

Nickel-based superalloys play a vital role in advanced aero-engines and gas turbines due to their exceptional high-temperature strength, oxidation resistance, and microstructural stability. The high content of alloying elements in these nickel-based superalloys significantly improves their strength, creep resistance and oxidation performance. This review summarizes the roles of various alloying elements in solid solution strengthening, precipitation strengthening and grain boundary reinforcement in nickel-based superalloys. Nevertheless, challenges such as elemental segregation during fabrication and limitations in high-temperature performance have hindered their widespread application. Therefore, microstructural evolution mechanisms during thermal deformation and the effects of heat treatment—including homogenization, solution treatment, and aging—on conventional and additively manufactured alloys are analyzed. The improvement of the high-temperature stability of nickel-based superalloys through improving the microstructure by the incorporation of ceramic particles is also discussed. In addition, high-throughput computing and machine learning-assisted design of alloy composition provide a new approach for achieving superalloys of high performance is emphasized. It is expected that this review will provide valuable guidance for the development of high-efficiency, high-performance nickel-based superalloys.