Refinement of Primary Carbides in GCr15 Bearing Steel During Solidification Process: A Review

High‐end bearing steels are increasingly critical in sophisticated equipment manufacturing fields, and GCr15 bearing steel is widely used in the production of high‐performance bearings. However, due to the high carbon and chromium content in GCr15 bearing steel, the large‐size primary carbides tend to be easily precipitated during its solidification process, which severely deteriorates the service life of bearing steels. Therefore, this paper aims to summarize previous research on the refinement of primary carbides in GCr15 bearing steel during solidification process, which includes the formation of primary carbides in steels, influence of adjustment of alloying elements, solidification cooling rate, and special smelting processes on primary carbides in steels. Although some significant improvement on the refinement of primary carbides is achieved through the application of above methods, the study about the influence of above methods on primary carbides in GCr15 bearing steel is still scarce. This paper summarizes the challenges identified in this study and outlines potential future research directions, which could provide the theoretical guidance for refinement of primary carbides in GCr15 bearing steel during solidification process.