Abstract: Preparation of bearing steel entails casting, solidification, and solid-state phase transformation, each crucial in controlling its microstructure evolution, particularly the precipitation behavior of carbides. This precipitation behavior represents a key technical bottleneck in enhancing rolling contact fatigue properties. After decades of research, the mechanisms by which strong magnetic fields influence phase transformations in steel are becoming increasingly understood, suggesting magnetic fields as a valuable tool for structural refinement in steel. Findings show that magnetic fields can enhance melt flow and solid particle migration by altering dendrite growth and morphology, resulting in improved hardness and wear resistance. Furthermore, during spheroidizing annealing, magnetic fields can promote carbide dissolution and uniform refinement, increase dislocation diffusion driving force, and optimize the formation of martensite and carbide precipitation during quenching and tempering processes. However, the response mechanisms of carbide electronic structures in strong magnetic fields remain unclear, with practical challenges such as high costs and limited processing capacity. Thus, further exploration is needed to make magnetic field applications in bearing steel and other high-performance steels more cost-effective and scalable.

Key words: bearing steel, magnetic field, carbides, solidification phase transformation, spheroidizing annealing, quenching and tempering