基体表面粗糙度对MoS_(2)/Ti薄膜摩擦磨损性能的影响EI北大核心CSCD

为揭示基体表面粗糙度对MoS_(2)/Ti固体润滑薄膜摩擦磨损性能的影响规律,并探究其摩擦磨损机理,采用磁控溅射方法,在不同表面粗糙度的轴承钢基体上沉积MoS_(2)/Ti薄膜。通过划痕测试仪、X射线衍射仪、场发射扫描电子显微镜和粗糙度轮廓仪,分别评价MoS_(2)/Ti薄膜的膜基结合力、物相成分、表面微观形貌以及表面粗糙度,并采用球-盘摩擦磨损实验研究干摩擦、固体-油复合润滑和固体-脂复合润滑条件下,MoS_(2)/Ti薄膜的摩擦磨损性能。结果表明:随着基体表面粗糙度的增加,MoS_(2)/Ti薄膜的表面粗糙度逐渐增加;薄膜中(002)_(MoS_(2))和(100)_(MoS_(2))衍射峰的强度先减弱后增加;薄膜与基体的结合性能降低。当基体表面粗糙度为0.01μm时,干摩擦条件下MoS_(2)/Ti薄膜具有良好的润滑特性,平均摩擦因数为0.101,磨痕浅且小;随基体粗糙度的升高,样品的平均摩擦因数和磨损率均是先增大后减小,薄膜的主要磨损机制由磨粒磨损转变为屑片形成和破碎。当基体粗糙度较大时(R_(a)=0.26μm),分子间相互作用的影响大于机械啮合作用。采用固体-油复合润滑,高基体粗糙度的薄膜磨损表面不再出现片层剥落现象,磨痕较浅,平均摩擦因数最高可减小19%。固体-脂复合润滑条件下,样品摩擦磨损性能较差,基体粗糙度对摩擦因数的影响不显著。

Effect of substrate surface roughness on friction and wear properties of MoS2/Ti films

The effect of the substrate surface roughness on tribological properties of MoS₂/Ti films, and the friction and wear mechanism was studied. MoS₂/Ti films were deposited on bearing steel with different surface roughness by magnetron sputtering. The adhesion strength between the film and substrate, phase composition, surface morphology and surface roughness of MoS₂/Ti films were obtained respectively by scratch tester, X-ray diffractometer(XRD), scanning electron microscope (SEM) and roughness profiler. And the tribological properties of MoS₂/Ti films under dry friction, solid-oil composite lubrication and solid-grease composite lubrication were studied by a ball-on-disk tribometer. The results show that with the increase of the substrate surface roughness, the surface roughness of MoS₂/Ti films increases, the intensity of (002)_MoS2 and (100)_MoS2 diffraction peaks first decreases and then increases, and the adhesion strength between the film and substrate decreases. When the surface roughness of the substrate is 0.01 μm, the MoS₂/Ti films have good lubrication characteristics under dry friction condition. The average friction coefficient is 0.101, and the wear scar is shallow and small. With the increase of substrate roughness, the average friction coefficient and the wear rate of the samples increase first and then decrease. Meanwhile, the main wear mechanism of the film changes from abrasive wear to chip formation and fragmentation. And the effect of intermolecular interaction is greater than that of mechanical engagement, when the substrate roughness of the samples is large (R_a=0.26 μm). Under the condition of solid-oil composite lubrication, there is no fragmentation phenomenon on the worn surface with large substrate roughness. The wear scar is shallow, and the average friction coefficient is reduced by about 19%. Under the condition of solid-grease composite lubrication, the tribological properties of the samples are poor, and the effect of the substrate surface roughness on the friction coefficient is not significant.