Superior high-temperature lubrication of MoS2/Ta/WB2 nanomultilayer film

To address the performance limitations of molybdenum disulfide (MoS2) in high-temperature environments, we fabricate a sandwich-like nanomultilayer film composed of alternating MoS2 and tungsten diboride (WB2) nanolayers, with Ta dopants, using unbalanced magnetron sputtering. This architecture demonstrates superior mechanical properties over a wide temperature range (25-400 degrees C), achieving a high hardness-to-elastic modulus (H/E) value of 0.084 at 400 degrees C. The film also maintains a low friction coefficient of 0.06 at 300 degrees C under high contact stress, enabled by the formation of a friction-induced tribofilm consisting of oxide nanoparticles (e.g., MoO3, WO3, Ta2O5) encapsulated by MoS2 (002) nanosheets. This design provides a promising strategy for developing high-performance lubricants capable of withstanding extreme operating conditions.