摘要
目的探究具有超薄结构的二维纳米片状MoS2的制备方法及其在发动机润滑油中的减摩抗磨性能。方法以七钼酸铵和硫脲为反应前驱物,油胺为反应溶剂,采用原位表面法制备出表面修饰有油胺分子的二维纳米片状MoS2。利用透射电镜(TEM)、红外光谱分析仪(FT-IR)、X射线光电子能谱仪(XPS)表征纳米片状MoS2的形貌特征、表面状态及化学组成。采用球盘式摩擦磨损试验机对其作为润滑添加剂在发动机润滑油中的摩擦学性能进行考察,并通过三维共聚焦表面形貌仪、扫描电镜和X射线光电子能谱仪对磨痕进行分析。结果所制备的具有超薄结构的二维纳米片状MoS2在发动机润滑油中具有良好的减摩和抗磨性能,当其添加量为3%时,摩擦系数降低27.1%,磨斑直径降低17.17%。在150℃高温下,使用纯发动机润滑油进行润滑时,摩擦初始阶段的摩擦系数高达0.5,出现润滑失效现象。然而,使用添加有3%二维纳米片状MoS2的润滑油进行润滑,150℃高温下的摩擦系数在整个实验过程中都比较平稳,磨损体积和最大磨痕深度为纯发动机润滑油润滑时的23.44%和28.53%。结论在摩擦过程中,两摩擦表面处于边界润滑状态,所制备的二维纳米片状MoS2随润滑油进入摩擦接触区,发挥良好的润滑效果。特别是在高温下,当发动机润滑油润滑失效时,二维纳米片状MoS2在摩擦表面生成富含MoS2的摩擦化学反应膜填充修复磨损表面,起到润滑作用。
The aim of this paper was to explore the preparation method of two-dimensional MoS2 nanosheets with ultra-thin structure and their friction-reducing and anti-wear properties in engine oils.In this paper,two-dimensional MoS2 nanosheets with surface modified by oleylamine molecules were prepared by in-situ surface method using ammonium heptamolybdate and thiourea as reaction precursors and oleylamine as the reaction solvent.The morphology,surface state,and chemical composition of the prepared MoS2 nanosheets were characterized by transmission electron microscopy(TEM),infrared(FT-IR),and X-ray photoelectron spectroscopy(XPS),respectively.Further,the tribological property of the fabricated two-dimensional nanosheet MoS2 as lubricating additives in engine oils was tested on a ball-on-disk tribometer,and the wear scars were analyzed by a white-light interference profilometer,scanning electron microscope(SEM)and XPS.Results showed that the prepared twodimensional MoS2 nanosheets with ultra-thin structure has good anti-friction and anti-wear properties in engine oils.The friction coefficient was decreased by 27.1%and the wear scar diameter was reduced by 17.17%after adding 3wt%two-dimensional MoS2 nanosheets into oils.It was worth pointing out that at the high temperature of 150℃,the friction coefficient suddenly increased to 0.5 at the initial stage of friction,and lubrication failure occurred when the pure engine oil was used for lubrication.However,for the case lubricated with two-dimensional MoS2 nanosheets,the friction coefficient was relatively stable during the whole friction process at the high temperature of 150℃.In addition,the wear volume and maximum wear scar depth were only 23.44%and 28.53%of these lubricated with the pure engine oil,respectively,at the high temperature of 150℃.During the friction test,the two friction surfaces were in the boundary lubrication region,and the two-dimensional MoS2 nanosheets with ultra-thin structure entered the friction contact area with lubricating oil,which exerted a good lubrication effect.Especially,when the lubrication of the pure engine oil failed at high temperature,the two-dimensional MoS2 nanosheets could form MoS2-based tribochemical reaction film on rubbing surfaces that filled and repaired the worn surfaces,which acted the lubrication effect.
作者
胡贇
廖智忠
易美荣
HU Yun;LIAO Zhi-zhong;YI Mei-rong(Key Laboratory of Tribology,School of Mechatronics Engineering,Nanchang University,Nanchang 330031,China)
出处
《表面技术》
EI
CAS
CSCD
北大核心
2020年第9期61-71,共11页
Surface Technology
基金
清华大学摩擦学国家重点实验室开放基金资助项目(SKLTKF19B06)。
关键词
超薄二维纳米片状MoS2
油胺修饰
润滑添加剂
减摩抗磨性能
磨损机制
边界润滑
ultra-thin two-dimensional MoS2 nanosheets
oleylamine modified
lubricating additives
friction-reducing and anti-wear properties
wear mechanism
boundary lubrication
