二硫化钨纳米粉体作为锂基润滑脂添加剂的摩擦学研究

Tribology of Nano-Tungsten Disulfide Powder as an Lubricating Additive for Lithium Grease

制备了二硫化钨纳米粉体作为添加剂的锂基润滑脂,采用SRV-Ⅳ摩擦磨损试验机考察了二硫化钨对锂基润滑脂摩擦学性能的影响,利用扫描电子显微镜(SEM)、能量色散X射线光谱仪(EDAX)、X射线光电子能谱仪(XPS)对磨损表面的微观形貌、元素含量和价态进行了表征,分析了其润滑机理.结果表明:二硫化钨纳米粉体能够显著提高锂基润滑脂的摩擦学性能.摩擦过程中,二硫化钨纳米粉体在摩擦副表面产生吸附沉积,并在高温高负荷条件下生成含有Fe_2O_3、FeSO_4、WO_3和Fe_3O_4的化学反应膜,从而共同产生润滑作用.

Lithium grease with nano-tungsten disulfide as lubricating additive was prepared in this study. The optimal SRV- tribometer was employed to investigate the influence of nano-tungsten disulfide powder on the tribological properties of lithium grease. The micro-morphology, chemical composition and chemical state of worn surface were characterized by using scanning electron microscope, energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. And the lubricating mechanism was analyzed. The results show that the tribological performances of lithium grease were greatly improved by adding nano-tungsten disulfide powder. In the friction process, adhesion and deposition of the nano-tungsten disulfide powder on the tribo-surface gave birth to the tribo-chemical film composed of Fe2O3, FeSO4, WO3 and Fe3O4 at high local temperature and heavy load. The good tribological performance was contributed by the tribo-chemical film.