Advances in surface modification technologies for high-performance bearing steels: wear-resistant, fatigue and corrosion resistant

Abstract

Bearing steel, as the core material of key transmission and support components, has its surface performance directly determining the reliability, stability, and service life of the bearing system. To address this, research has established four major surface modification technology systems: surface mechanical strengthening, surface heat treatment strengthening, surface coating strengthening, and hybrid strengthening. This review systematically summarizes the progress of these four systems, focusing on their strengthening mechanisms, microstructural evolution, and effects on the service performance of bearings. Surface mechanical strengthening improves the surface layer’s resistance to crack initiation and propagation through grain refinement induced by plastic deformation, dislocation multiplication, and residual compressive stress, significantly enhancing the rolling contact fatigue life, but the strengthened layer is shallow and may cause surface roughening. Surface heat treatment strengthening, by regulating the phase composition, microstructure, and hardness gradient, forms a high-hardness layer and a favorable residual stress, achieving the synergistic improvement of wear and fatigue resistance, yet faces challenges such as microstructural uniformity and thermal deformation. Surface coating strengthening, by constructing protective layers with high hardness, low friction, and corrosion resistance, achieves friction isolation and interface protection, and has advantages in improving wear resistance and extreme environment adaptability, but its long-term reliability is constrained by interfacial bonding, residual stress, and coating failure. Single strengthening methods thus exhibit limitations in layer depth, surface integrity, interfacial stability, and hardness–toughness matching, making it difficult to meet the requirements of long life and high reliability for bearings under extreme conditions. In contrast, hybrid strengthening technologies, through the synergistic coupling of plastic deformation, microstructural regulation, and coating protection, achieve the optimization of surface microstructure, residual stress, and interfacial characteristics, providing a solution to break through these performance bottlenecks. This review therefore highlights hybrid strengthening as the central thread that unifies the four technology systems, clarifies the current status and future trends from the perspectives of strengthening mechanisms and performance control, and provides insights for surface design and engineering application of high-performance bearing steel.