为探究稀土处理对贝氏体/马氏体轴承钢摩擦磨损性能的影响，本工作通过油润滑滑动摩擦磨损实验系统评估了贝氏体/马氏体(B/M)轴承钢的摩擦磨损性能，并分析了稀土处理对其性能的调控作用。同时，采用接触式轮廓仪、白光干涉仪(WLI)、SEM、TEM、EBSD、透射菊池衍射(TKD)和XPS等多种表征手段，对含/无稀土的B/M轴承钢磨痕表面形貌及截面区域的组织演化进行了全面表征和深入分析。结果表明，稀土处理能够显著提高B/M轴承钢的耐磨性，将其磨损量减少25%以上，达到与马氏体轴承钢相近的水平。在20 min的摩擦时间内，含/无稀土的B/M轴承钢的磨损机制均为磨粒磨损。稀土轴承钢中小尺寸马氏体/奥氏体块和较少的残余奥氏体相变减弱了磨面下的显微组织演化，与较高占比的二次碳化物协同作用，使得磨屑更易断裂，从而减少大尺寸磨屑的生成，进而减小磨屑引起的应力和犁削的磨损量，提高钢的耐磨性。当磨擦时间延长至1 h时，含/无稀土的B/M轴承钢主要磨损机制均转变成氧化磨损。稀土处理有利于硬度高且与基体结合强的Fe₃O₄氧化膜的生成，使得稀土轴承钢表现出优异的抗氧化磨损性能。

Bainite/martensite (B/M) multiphase bearing steel has become a research focus owing to its superior combination of strength and toughness compared with conventional martensite bearing steel. Our previous study confirmed the significantly improved toughness and fatigue properties of B/M bearing steel and demonstrated that rare-earth (RE) element incorporation can enhance its overall mechanical properties, highlighting the promising application potential of RE-incorporated B/M bearing steel. However, reports on the tribological properties of B/M bearing steel remain limited. Therefore, it is necessary to investigate the friction and wear behavior of B/M bearing steel and the effect of the RE element on the behavior. In this study, oil-lubrication sliding wear tests were conducted to evaluate the friction and wear behavior of B/M bearing steel and the effects of RE element incorporation. After the wear tests, the surface morphology and microstructural evolution beneath the wear tracks of the B/M bearing steels with and without RE elements were comprehensively characterized and analyzed using contact profilometry, a white-light interferometer, SEM, TEM, EBSD, transmission Kikuchi diffraction, and XPS. The results indicated that RE element incorporation significantly enhanced the wear resistance of B/M bearing steel, reducing material loss by >25% and achieving performance comparable to that of conventional martensite bearing steel. During the initial 20 min of the sliding wear test, B/M bearing steel with and without RE elements exhibited abrasive wear. The presence of smaller martensite/austenite blocks and a reduced fraction of retained-austenite transformation in the RE-containing steel inhibited microstructural evolution beneath the wear surface, reduced the generation of large wear debris, and decreased the debris-induced stress and plowing-induced wear volume, improving wear resistance. When the sliding duration was extended to 1 h, the primary wear mechanism for B/M bearing steel with and without RE elements transitioned to oxidative wear. RE element incorporation facilitated the formation of hard Fe₃O₄ oxide films with strong adhesion to the matrix, resulting in the excellent resistance of the RE-containing steel to oxidative wear.