MoS2基复合薄膜真空高温摩擦学性能及其机理研究

采用闭合场非平衡磁控溅射技术分别制备了纯MoS2薄膜以及MoS2-Ti和MoS2-Ti-TiB2复合薄膜，利用真空高温摩擦试验机对比考察三种薄膜在真空环境中25~300 ℃下的摩擦学性能，通过拉曼光谱(Raman)、X射线衍射(XRD)和透射电镜(TEM)等分析复合元素对薄膜结构的影响以及摩擦前后薄膜结构的变化，探讨摩擦磨损机理. 结果表明：纯MoS2薄膜以(002)和(100)晶面取向生长，结构疏松，硬度低，在真空不同温度下摩擦寿命很短；Ti和TiB2复合后，薄膜呈现致密的非晶结构，硬度升高；MoS2-Ti薄膜在低温下(25和100 ℃)下具有优异的摩擦学性能，当温度达到200 ℃以上时，摩擦寿命急剧降低；MoS2-Ti-TiB2复合薄膜在25~300 ℃全温度范围内都保持低的摩擦系数和磨损率，这与其致密的非晶结构、摩擦界面MoS2 (002)晶面有序化以及高硬度耐高温TiB2掺入有关；低温下薄膜以磨粒磨损为主，高温下以擦伤为主.Pure MoS₂ thin films, MoS₂-Ti composite thin films and MoS₂-Ti-TiB₂ composite thin films were respectively prepared via closed-field unbalanced magnetron sputtering. The tribological properties of the three films were comparatively investigated at 25–300 ℃ in vacuum using a vacuum high-temperature friction tester. The effects of composite elements on the film microstructure and the structural changes of the films before and after friction tests were analyzed via Raman spectroscopy (Raman), X-ray diffraction (XRD) and transmission electron microscopy (TEM), and the friction and wear mechanisms were discussed. The results show that: Pure MoS₂ thin films grow with (002) and (100) crystal plane preferred orientations, feature loose microstructures and low hardness, and exhibit short friction lifetimes at various temperatures in vacuum. After incorporating Ti and TiB₂, the composite films form dense amorphous microstructures with improved hardness. The MoS₂-Ti thin films demonstrate excellent tribological properties at low temperatures (25 and 100 ℃), but their friction lifetimes decrease sharply when the temperature rises above 200 ℃. The MoS₂-Ti-TiB₂ composite thin films maintain low friction coefficients and wear rates across the full temperature range of 25–300 ℃, which is attributed to their dense amorphous microstructure, the ordering of MoS₂ (002) crystal planes at the friction interface, and the incorporation of high-hardness, high-temperature-resistant TiB₂. At low temperatures, the wear mechanism is dominated by abrasive wear, while at high temperatures, scuffing wear is the main wear mode.