Research Progress on Microstructure Control and Computational Design of Strengthening Phases in High-Speed Steel

High-speed steels (HSS) occupy an important position in industrial cutting and roll applications due to their excellent hardness, red hardness, and comprehensive mechanical properties. Their service behavior is essentially determined by the type, morphology, distribution, and intrinsic properties of the strengthening phases. This review systematically summarizes research progress on the main strengthening phases in HSS, focusing on three aspects: (i) the types and crystal structure characteristics of strengthening phases such as carbides, borides, and nitrides in HSS; (ii) the current status of morphology and distribution control of strengthening phases through modification treatment, hot deformation, heat treatment, and deep cryogenic treatment; (iii) research on intrinsic properties and interfacial behavior of strengthening phases based on first-principles calculations and materials genome engineering. On this basis, it is pointed out that combining first-principles calculations, high-throughput thermodynamic simulations, and machine learning to construct an integrated design framework of composition-process-microstructure-property for HSS is an important approach to promote HSS from macroscopic properties to atomic-scale precise regulation, providing a theoretical basis for composition optimization and process development of new HSS.