Amorphous phase grain-boundary reinforce random nanocrystals molybdenum disulfide endows the film with high service life and load-bearing capacity

Molybdenum disulfide (MoS 2 ) is a widely used solid lubricant material, but its sensitivity to moisture and inherent softness with self-sacrificing nature for lubrication have given rise to challenges in its applications. The recently emerged HiPIMS technology, featuring a high plasma ionization rate, can endow the deposited films with high adhesion and high density. In this work, this technology was employed to produce isotropic MoS 2 films with high density and high hardness up to 4.6 GPa. The tribological tests under a high load of 30 N in both ambient air and vacuum showed a common low fiction coefficient <0.03 along with low wear, which showed substantially improved tribological robustness for film in changing environments under high loads than those of traditional sputtered MoS 2 films tested under the same condition. Raman, SEM, and TEM analyses of the MoS 2 layers before and after the friction tests indicated parallel re-orientation of the MoS 2 along the sliding direction for tests in both air and vacuum without significant oxidation, where MoS 2 layers from tests in air sharing morphological features more similar to those of the as deposited film due to friction. This work provides new guidelines for depositing pure MoS 2 films with high load bearing capacities and superior tribological performance across vacuum and ambient air.