A review of the precipitation strengthening in ultra-high strength martensitic steel

Martensite is a very important microstructure in ultra-high-strength steel materials, and enhancing the strength of martensitic steels often involves the introduction of precipitated phases within the martensitic matrix. Despite considerable research efforts have been devoted in this area, a systematic summary of these advancements is lacking. In this review, some prevalent precipitates observed in ultra-high strength martensitic steels are summarized, focusing primarily on carbides (e.g., MC, M2C, M3C) and intermetallic compounds (e.g., NiAl, Ni3X, Fe2Mo). The precipitation-strengthening effect of these precipitates on ultra-high strength martensitic steels is discussed from the aspects of heat treatment processes, the microstructure of precipitate-strengthened martensite matrix, and mechanical performance. Finally, a perspective on the development of precipitated phase strengthened martensitic steel is provided, aiming to contribute to the advancement of ultra-high strength martensitic steel. This review not only highlights significant findings but also underscores ongoing challenges and opportunities within the field of ultra-high strength martensitic steel development.