凹凸棒石润滑脂添加剂对45号钢的微动磨损及自修复性能研究

将不同质量分数经表面有机改性的凹凸棒石粉体分散在基础油中，作为添加剂添加至基础脂中，制备出凹凸棒石含量不同的3号锂基润滑脂。利用SRV微动摩擦磨损试验机考察凹凸棒石在3号脂中的最佳添加量、减摩性、抗磨性与对45#钢的自修复性能，并与未添加该材料的锂基基础脂进行对比。借助电子扫描电镜（SEM）、X射线能谱仪（EDS）、光电子能谱（XPS）分析试样磨损表面的形貌、元素组成及价态。结果表明：基础脂添加不同质量分数凹凸棒石，摩擦系数与磨损率均出现不同程度的下降，当添加量为0.8%时，效果最佳；摩擦表面较基础脂润滑光滑平整，没有明显的磨损特征，并在摩擦表面形成区别于基体材料含元素C、Fe、Mg、Al、O和Si的磨损修复层。

FRETTING WEAR AND SELF-REPAIRING PROPERTIES OF C45 STEEL UNDER LUBRICATION OF LITHIUM GREASE CONTAINING ATTAPULGITE POWDER

Different mass fractions of organic modified attapulgite powder scattered into the base oil as additive were added into lithium grease during the 3# grease preparation. The amount of attapulgite and the friction reduction, anti-wear and self-repairing properties of the lithium grease were evaluated using a SRV friction wear machine. As a comparison, the tribological properties of base lithium grease were also investigated. Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectroscopy (EDS) and X-ray Photoelectron Spectroscopy (XPS) were employed to analyze the worn surface topography and the elements on the worn surface. The results show that after adding different amount of modified attapulgite into lithium grease, the friction coefficient and the wear rates of the grease decline in different extent. When 0.8% attapulgite is added, the results are the best. The worn surface lubricated with grease containing attapulgite is smoother more than that lubricated with blank one and there were no obvious wear characteristics. There is a repairing film formed on the worn surface, which is different from substrate material and contains C, Fe, Si, Mg, O and Al elements.