采用多靶射频磁控溅射方法,在Si(100)衬底上制备不同调制周期(Λ分别为54 nm、30 nm、18 nm)MoS2/类金刚石(DLC)多层薄膜.利用扫描电子显微镜、拉曼光谱仪、X射线衍射仪、透射电子显微镜、纳米压痕仪研究多层膜的形貌、微观结构及力学性能受调制周期的影响规律;利用球-盘摩擦试验机考察薄膜在大气环境下的润滑性能.结果表明:采用交替沉积MoS2/DLC多层膜可有效抑制溅射MoS2中柱状结构生长,制备的薄膜结构致密;多层膜硬度随调制周期的增加而增大.透射断面分析表明:多层膜层间界面不平整但周期性结构清晰且致密,其调制周期厚度与试验设定值基本一致.与纯MoS2薄膜相比,调制周期为54 nm的薄膜具有较好的法向承载及弹性恢复能力,其硬度最高,达7.15 GPa;法向载荷为5 N时,该薄膜在大气环境(相对湿度约30%)下具有最低的摩擦系数(0.09)和最低的磨损率[1.34×10–7 mm3/(N·m)].
A series of MoS2/diamond-like carbon(DLC) multilayer films with three different modulation periods(i.e. Λof 54 nm, 30 nm and 18 nm) were deposited on silicon wafers(100) using a multi-target radio frequency magnetron sputtering system. The influence of modulation periods on the morphology, microstructure and mechanical properties of multilayer films were investigated with scanning electron microscope, Raman spectrometer, X-ray diffractometer,transmission electron microscope and nanoindentation. The lubricating properties of the films were investigated by the ball-on-disk friction tester in ambient atmosphere. Results show that the alternative deposition MoS2/DLC multilayerfilms effectively suppressed the growth of columnar structure in sputtered Mo S2 and thus the produced films had compact structure. The hardness of multilayer films increased as the modulation period increased. Transmission analysis of cross-sectioned multilayer films revealed that the interface between layer was not smooth whereas the periodic structure was dense and well-defined. In addition, the thickness of modulation period was basically consistent with the initial set value. Compared with pure Mo S2 film, the multilayer film with modulation period of 54 nm had better loadbearing capacity and elastic recovery capacity, and the corresponding hardness reached the highest value(7.15 GPa).Furthermore, the film exhibited the lowest friction coefficient(0.09) and wear rate of 1.34×10–7 mm3/(N·m) under a normal load of 5 N in ambient atmosphere(with relative humidity of about 30%).