采用尺寸为0.5~4µm 的层片状蛇纹石粉末，通过高能球磨对其进行油基细化、改性和分散，然后添加到基础油(CD 15W/40柴油机润滑油)中制成含油溶性蛇纹石微粉的润滑剂。借助环–块摩擦磨损试验机研究蛇纹石颗粒作为润滑油添加剂对类轴–轴瓦摩擦副表面的自修复效应，并探讨其作用机理。结果表明：在载荷为600 N、蛇纹石颗粒含量(质量分数)为0.5%时，润滑油具有最佳的摩擦学性能及自修复性能，摩擦因数和磨痕宽度分别较基础油润滑时降低约9.7%和40.7%；磨损表面较平整光滑，其上形成厚约0.68µm 的自修复层。修复层主要由铁的多种氧化物、石墨、有机残留物及少量 FeS 组成，具有较高的力学性能；蛇纹石颗粒对摩擦副表面具有精细研磨作用，不仅能降低表面的粗糙度，而且在高压闪温条件下释放更多的活性氧参与摩擦界面的氧化反应，促进保护膜的形成并与石墨及有机残留物产生协同作用，实现摩擦表面的润滑与原位自修复。%The oil-soluble serpentine powders were prepared out of the flaky serpentine powders with particle size of 0.5~4 µm using the integral process of oil-based refinement, modification and dispersion with high-energy ball-milling method. The as-prepared additive was added to the Great Wall CD 15W/40 diesel oil to form various lubricants and their self-restoration effects on the tribosurfaces analogue of shaft-bushing contact were investigated using the ring-on-block friction and wear tester. In addition, the corresponding mechanism was discussed. Results indicate that the oil with 0.5%content of serpentine particles shows most excellent tribological properties and self-restoration performance at 600N. The friction coefficient and width of wear trace decrease by 9.7% and 40.7% relative to those of the base oil, respectively. The worn surface is smooth with a restoration film approximating 0.68 µm. The film with higher mechanical properties mainly consists of multiple iron oxides, graphite, residual organics and a small amount of iron sulfide. The serpentine particles present fine grinding effects on the tribosurface, which contributes to the decrease in surface roughness and the release of more active oxygen atoms from serpentine particles to participate of the oxidation reactions at the friction interface and promote the formation of protective film with the local high pressure and flash temperature. Moreover, the film has synergistic effects with the graphite and residual organics, which is responsible for the lubrication and in situ self-restoration effect on the friction surface.
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