Fe/洋葱状富勒烯作为润滑油添加剂的摩擦性能

Tribological properties of Fe/onion-like fullerenes as lubricant additives

采用化学气相沉积法(CVD)以二茂铁为催化剂,乙炔为碳源制备了Fe/洋葱状富勒烯(Fe/onion-like fullerenes,Fe/OLFs),通过场发射扫描电子显微镜(FESEM)、高分辨透射电镜(HRTEM)和X射线衍射(XRD)分析了Fe/OLFs的晶体结构和形貌。结果表明,所制备的Fe/OLFs是由同心封闭壳层组成的准球形颗粒,其层间距为0.349nm,与石墨的层间距0.336nm相接近。在MRS-10A型四球摩擦试验机上考察了Fe/OLFs作为长城牌SE级15W-40汽油机油的添加剂的摩擦性能。摩擦试验表明,Fe/OLFs作为润滑油添加剂表现出优良的抗磨减摩性能,并能显著改善基础油的承载能力,当添加量为0.02%(质量)左右时,润滑油的抗磨减摩性能最佳,与基础油相比摩擦系数下降40.8%;在相同的质量分数和载荷下Fe/OLFs作为润滑油添加剂在减摩性能上均优于CNTs。

Fe/onion-like fullerenes （Fe/OLFs） were synthesized by chemical vapor deposition （CVD） from acetylene with ferrocene as catalyst.Field-emission scanning electron microscopy （FESEM）,high-resolution transmission electron microscopy （HRTEM） and X-ray diffraction （XRD） techniques were used to characterize the morphologies and microstructures of the Fe/OLFs.The results indicated that the Fe/OLFs were quasi-spherical particles with closed concentric shells.The distance between the shells was approximately 0.349 nm that closely matched the lattice parameter d002 （0.336 nm） of bulk graphite.Furthermore,Fe/OLFs were added to base lubricant and the tribological properties of Fe/OLFs were investigated with a four-ball type tribometer.The tribological results showed that Fe/OLFs as lubricant additives exhibited good friction-reducing ability at different additive concentrations and applied loads.Meanwhile,they could also strikingly improve the load-carrying capacity of base lubricant.The optimum content of Fe/OLFs was 0.02%（mass） for improving the friction-reducing ability of base lubricant,while the maximum reduction of friction coefficient was about 40.8%.Both Fe/OLFs and carbon nanotubes （CNTs） had friction-reducing ability,while the friction reduction of Fe/OLFs was better than CNTs with the same mass fraction and applied load.