Structure and tribological properties of MoS₂low friction thin films

Abstract

Abstract. The main aim of the studies was the deposition of the AlCrN film, covered by molybdenum disulphide (MoS2) -based lubricant, on the austenitic steel substrate. The AlCrN and MoS2 layers were deposited by PVD lateral rotating ARC-cathodes (LARC) and magnetron sputtering technology on the X6CrNiMoTi17-12-2 respectively. Structural characterizations of the MoS2 thin films have been carried out using SEM (scanning electron microscopy) and AFM (atomic force microscopy) to determine the surface topography as well as HRTEM (high-resolution transmission electron microscopy) and Raman spectroscopy for structural investigations. The tribological wear relationships using ball-on-disc test were specified for surface layers, determining the friction co-efficient and mass loss of the investigated surfaces. Tests of the coatings' adhesion to the substrate material were made using the scratch test. HRTEM investigation shows an amorphous character of the MoS2 layer. In sliding dry friction conditions, the friction co-efficient for the investigated elements is set in the range between 0.4-0.5. The investigated coating reveals high wear resistance. The coating demonstrated a dense cross-sectional morphology as well as good adhesion to the substrate. The good properties of the PVD AlCrN+MoS2 coatings make them suitable in various engineering and industrial applications.

Molybdenum disulfide/carbon multilayer films achieve ultra‐low wear in vacuum

“…The Mo3d 5/2 peak is located at 236.1 eV and corresponds to Mo 6+ in the MoO 3 structure 30,31 . As shown in Figure 2C, the Mo3d 5/2 and Mo3d 3/2 double peaks are located at 229.8 and 233.0 eV, respectively, which correspond to the crystal structure of 2H‐MoS 2 , the 2H‐MoS 2 has a lubrication function 32,33 . Furthermore, as shown in Figure 2B,C, the C1s and O1s spectra exhibit several peaks that can be attributed to different chemical environments.…”

“…30,31 As shown in Figure 2C, the Mo3d 5/2 and Mo3d 3/2 double peaks are located at 229.8 and 233.0 eV, respectively, which correspond to the crystal structure of 2H-MoS 2 , the 2H-MoS 2 has a lubrication function. 32,33 Furthermore, as shown in Figure 2B,C, the C1s and O1s spectra exhibit several peaks that can be attributed to different chemical environments. The C1s spectrum exhibits two peaks that correspond to C-C and C-O bonds, respectively.…”

Tribological Evaluation of Lead-Free MoS2-Based Solid Film Lubricants as Environmentally Friendly Replacements for Aerospace Applications

“…Figure 8 shows the Raman spectroscopy on both the coatings for the worn and unworn surfaces. The peaks at Raman shift approximately 380 cm −1 and 400 cm −1 are clearly visible from Figure 8 which corresponds to crystalline MoS 2 [4,5,9]. For unworn surfaces of both, the green and non-green lubricants, (Figure 8b,d), the intensity of the peaks corresponding to MoS 2 was similar for both lubricants and relatively low, which could be due to the influence of the additional elements in the lubricant in the as deposited condition.…”

“…The main drawback of using MoS 2 is that its tribological behavior is very sensitive to environmental conditions. While pure MoS 2 performs well in vacuum conditions, it can exhibit higher friction and premature failure when operating in humid/ambient conditions, which is sometimes attributed to the formation of MoO 3 [5,6]. To overcome some of these challenges, MoS 2 is usually doped with metals/composites, such as Au, Ti, Ni, Ag, PbO, Sb 2 O 3 , WS 2 , WSe 2, etc.…”

Assessment of Tribological Properties of Low Friction Thin Layers Produced by Vacuum Methods

“…TiN, CrN, TiC, WC, CrC and DLC). These coatings improve the properties or adapt to the specific requirements of the regime frequently subjected to modification by additives of metals or non-metals or creation of the layer systems [5,10]. The lubrication mechanisms in these coatings depend mainly on their structure [7,8].…”