摘要： 【目的】提升聚四氟乙烯复合涂层在风电滑动轴承的严苛工况下的适用性。【方法】通过引入改性碳化硼（ B₄C）和六方氮化硼（ h-BN），制备了一种聚四氟乙烯（ PTFE）基复合涂层，采用喷涂 -热固化法制备于锡青铜基材表面，并研究了填充材料比例对涂层摩擦学性能的影响。【结果】  B₄C通过硅烷偶联剂 KH550改性处理后，提高了颗粒分散性和与基体的相容性，而 h-BN作为固体润滑剂，凭借其层状结构在摩擦界面形成稳定的润滑转移膜，两者共同作用改善了复合涂层表面的润湿性、热稳定性和力学性能。添加 4%h-BN和 6%改性  B₄C的复合涂层表现出最佳的摩擦学性能，摩擦系数降低了 35%，磨损质量降低了约 50%。通过三维轮廓图、超景深显微镜和扫描电子显微镜（SEM）分析，发现添加的B₄C和 h-BN有效降低了磨损表面的裂纹密度和磨粒堆积。此外，改性 B₄C颗粒的高硬度增强了涂层的承载能力，而 h-BN的润滑作用显著减少了黏着磨损和磨粒磨损。复合涂层中观察到的主要磨损机制是磨粒磨损和黏着磨损。【结论】建立了基于多种颗粒增强和润滑膜保护的减摩耐磨机理，为 PTFE基复合涂层在风电滑动轴承领域扩大应用提供了理论支持和技术参考。

关键词: 聚四氟乙烯, 六方氮化硼, 改性碳化硼, 自润滑涂层, 摩擦学性能

Abstract: ［Objective］To enhance the applicability of polytetrafluoroethylene（PTFE）composite coatings in the severe working conditions of wind turbine plain bearings.［Methods］ A polytetrafluoroethylene（PTFE）-based composite coating was developed by incorporating modified boron carbide（B₄C）and hexagonal boron nitride（h-BN）. The coating was prepared on a tin-bronze substrate using a spray-thermal curing process，and the effects of filler content on its tribological performance were investigated.［Results］B₄C was surface-modified with the silane coupling agentKH550 to enhance its dispersion and compatibility with the matrix. Meanwhile，h-BN，acting as a solid lubricant，formed a stable lubricating transfer film at the frictional interface due to its layered structure. The synergistic interaction between the two fillers enhanced the wettability，thermal stability，and mechanical properties of the composite coating. Experimental results showed that the composite coatingcontaining 4% h-BN and 6% modified B₄C exhibited the best tribological performance，achieving a35% reduction in the coefficient of friction and approximately a 50% decrease in wear rate. Analysis via3D profilometry，ultra-depth optical microscopy，and scanning electron microscopy（SEM）revealed that the addition of B₄C and h-BN effectively reduced crack density and abrasive particle accumulationon the worn surface. Furthermore，the high hardness of the modified B4C particles enhanced the load-bearing capacity of the coating，while the lubricating effect of h-BN significantly mitigated adhesiveand abrasive wear. The dominant wear mechanisms observed in the composite coating were abrasivewear and adhesive wear.［Conclusion］ This work proposes a friction-reducing and wear-resistantmechanism based on multi-particle reinforcement and lubricating film protection，providing theoreticalsupport and technical reference for the extended application of PTFE-based composite coatings in windturbine sliding bearings.

Key words: polytetrafluoroethylene（PTFE）, hexagonal boron nitride（h-BN）, modified boron carbide（B₄C）, self-lubricating coating, tribological property

中图分类号: 

• TQ637