Review on Heat Treatment and Surface Modification Technology of High‐Strength Bainite Steels

Bainite steels with high strength, high toughness, and excellent wear resistance are gradually used in railway crossing, rail and wind power bearing, and other fields. The rapid development of modern industry has made the service environment of bainite steel in the heavy industry more and more harsh, which requires not only good overall performance of bainite steel matrix but also excellent surface properties. A lot of research work has been carried out to improve the properties of the bainite steel matrix and surface. In this review, the development of heat treatment technology of high‐strength bainite steels is introduced, including austempering above and below martensite starting temperature, continuous cooling, and multistep austempering processes. Afterward, the surface modification technology of high‐strength bainite steel is summarized emphatically, including carburizing, surface alloying, laser cladding, and integrated strengthening technology. Finally, the future research direction of high‐strength bainite steel is prospected based on the current research status and application performance requirements.