片状纳米MoS2的制备及其在油润滑中的减摩抗磨性能研究

Preparation of Flaky Nano-MoS_2 and Its Anti-friction and Anti-wear Performance in Oil

目的探究片状纳米MoS_2的制备工艺及其在油润滑中的减摩抗磨性能。方法以钼酸钠和硫脲为原料,采用水热反应法在220℃条件下制备片状纳米MoS_2,利用红外(FT-IR)、X射线衍射仪(XRD)、透射电镜(TEM)、高分辨透射电镜(HRTEM)、能量色散谱仪(EDS)表征纳米颗粒的化学成分、晶体结构等理化性质。使用硅烷偶联剂(KH570)对其进行表面包覆改性,并使用超声处理将其分散到石蜡油中,形成润滑油分散体系。采用球-盘式摩擦磨损试验机对其作为添加剂在润滑油中的减摩抗磨性能进行考查,通过SEM、EDS等结果建立理论模型,并探究其减摩抗磨机理。结果制备出粒径在30~100 nm的片状纳米级MoS_2。石蜡油中添加片状纳米MoS_2可以显著改善其摩擦学性能。当添加量为1.0%(质量分数)时,摩擦系数比用纯石蜡油低约53.4%,磨斑直径比用纯石蜡油降低约41.1%。当用纯石蜡油作为润滑剂时,对偶盘磨损表面表现出了明显的犁沟磨损,而当用纳米润滑油作为润滑剂时,对偶盘的磨痕宽度最高降低了43.9%。结论片状纳米MoS_2可随润滑油流动进入摩擦接触界面,并随着界面的相对滑动吸附在摩擦表面形成沉积膜,从而达到减摩耐磨的效果。

The work aims to study the preparation method of Flaky nano-MoS2 and its tribological applications in oil lubrication.Flaky nano-MoS2 was prepared by hydrothermal reaction at 220℃with sodium molybdate and thiourea as raw materials.The chemical compositions,crystal structure and other physicochemical properties of the nano-sheets were characterized by FT-IR,XRD,HRTEM and EDS,respectively.After the surface was coated and modified by silane coupling agent(KH570),KH-MoS2 was dispersed into the paraffin oil through ultrasonic treatment to form the lubrication oil disperse system.Further,the tribological properties of nano-sheets in the composite lubrication oil as additives were tested on a ball-on-disk tribometer.The theoretical model was established according to the results of SEM,EDS,etc.And the tribological properties were investigated.The flaky nano-MoS2 with the sizes of 30~100 nm was prepared.The tribological performance of paraffin oil could be significantly improved after the surface-coated MoS2 was added.When the additive amount of MoS2 was 1.0 wt%,the coefficient of friction(COF)was 53.4%lower than that of pure paraffin oil and the diameter of the wear tracks was 41.1%less than that of pure paraffin oil.Besides,obvious furrows could be observed on the surface of the disk when pure paraffin oil was used as lubricant.The width of wear track with nano-oil as lubricant decreased by 43.9%to the maximum extent.KH-MoS2 can flow into the frictional contact interface along with the lubricant and form a deposited film on the contact region by being attached to the friction surface as the interface slides relatively to achieve excellent friction-reducing and wear-resisting effect.