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

To address the performance limitations of molybdenum disulfide (MoS 2 ) in high-temperature environments, we fabricate a sandwich-like nanomultilayer film composed of alternating MoS 2 and tungsten diboride (WB 2 ) nanolayers, with Ta dopants , using unbalanced magnetron sputtering . This architecture demonstrates superior mechanical properties over a wide temperature range (25–400 °C), achieving a high hardness-to-elastic modulus (H/E) value of 0.084 at 400 °C. The film also maintains a low friction coefficient of 0.06 at 300 °C under high contact stress, enabled by the formation of a friction-induced tribofilm consisting of oxide nanoparticles (e.g., MoO 3 , WO 3 , Ta 2 O 5 ) encapsulated by MoS 2 (002) nanosheets . This design provides a promising strategy for developing high-performance lubricants capable of withstanding extreme operating conditions.