MoS2/C复合薄膜多环境摩擦学行为的研究

Tribological Behavior of MoS2/C Composite Films in Multiple Environments

目的考察不同摩擦环境(真空、PAO、不同对磨副和温度)对MoS2/C复合薄膜摩擦性能的影响,并探究其摩擦磨损机理。方法使用直流磁控溅射技术(DCMS)和高功率脉冲磁控溅射技术(HiPIMS)在高速钢和硅基底上沉积MoS2/C复合薄膜。利用多功能摩擦试验机表征薄膜在空气、PAO、不同温度条件下的摩擦学行为。利用真空摩擦试验机表征薄膜在真空及不同对磨副条件下的摩擦性能。利用场发射扫描电子显微镜(SEM)、能谱仪(EDS)及共聚焦激光拉曼光谱仪,分析摩擦测试后,薄膜和对磨副上的形貌、磨屑成分等。结果真空下,除氧化锆外,其他对磨副均使薄膜迅速失效。MoS2含量超过50%时,薄膜可以在真空中维持较低的摩擦系数,约为0.1。PAO环境下,边界润滑阶段摩擦系数为0.08,流体润滑阶段摩擦系数最高为0.1。随着温度从25℃升高至450℃,薄膜摩擦系数由0.09降低至0.026,450℃下,薄膜在700 s时失效。结论真空下,氧化锆和氧化铝作为对磨副可以降低MoS2/C复合薄膜的粘着性,且复合薄膜中MoS2含量超过50%,可以展示出更好的摩擦性能。PAO油润滑环境下,摩擦行为主要取决于PAO的性质。高温环境下,更高的石墨化程度与MoS2再结晶可以降低薄膜的摩擦系数。

The work aims to study the influences of different environment (vacuum, PAO, different counterparts and tem-perature) on tribological properties of MoS2/C composite films, and explore the friction mechanism. MoS2/C composite films were deposited by direct current magnetron sputtering (DCMS) and high power impulse magnetron sputtering (HiPIMS) on high-speed steel and silicon substrate. Tribological behavior of the composite films in air, PAO, and different temperature were tested with a multifunction tribometer, and tribological properties of the composite films in the vacuum and different counterparts were evaluated with a vacuum tribometer. The morphologies and chemical composition of films and wear debris were analyzed by field emission scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and confocal laser Raman spectroscopy. In vacuum, all films were worn out, except ZrO2 counterparts. Films with MoS2 content more than 50% could maintain low friction coefficient in the vacuum, about 0.1. In PAO, the friction coefficient was 0.08 in the boundary lubrication stage, and was 0.1 in hydrodynamic lubrication. The friction coefficient decreased from 0.09 to 0.026 with the temperature increasing from 25 ℃ to 300 ℃, but the film failed at 450 s at 700 ℃. In vacuum, ZrO2 and Al2O3 can reduce the adhesion of MoS2/C composite film as counterparts and the composite films with MoS2 content more than 50% exhibit better tribological properties. In PAO lubricating oil, the tribological property mainly depends on the properties of PAO. In high-temperature, severe graphitization and recrystallization of MoS2 in the films can reduce the coefficient of friction of the film.