High-entropy alloys have made significant progress in high mechanical properties, wear resistance, and corrosion resistance properties. Excellent tribological properties, especially high-temperature lubrication, have become another sought performance. In this work, VAlTiCrW high-entropy alloy film with body-centered cubic (BCC) structure was prepared on superalloy substrate by magnetron sputtering. It is found that the VAlTiCrW film shows very low friction coefficient of 0.15 and a low wear rate of 10⁻⁵ orders of magnitude at 800 °C. After 800 °C oxidation, the film can still obtain a friction coefficient of no more than 0.2 at 700 °C. XRD and TEM revealed the formation of ternary oxide AlV₃O₉ with preferred orientation of (002) crystal plane with large spacing of 0.71 nm on the wear surface of the film, a high-temperature lubricating phase that has not been reported, realizes the low friction coefficient. This AlV₃O₉ can be formed by tribochemical reaction under the thermal-mechanical action at 700 °C, but pre-oxidation at 800 °C is the prerequisite in order to form the precursors of V-rich and Al-rich oxide layer.

高熵合金在高机械性能、耐磨性和耐腐蚀性能等方面取得了重大进展。优异的摩擦学性能，尤其是高温润滑性能，已成为另一种追求的性能。本工作采用磁控溅射在高温合金基体上制备了体心立方（BCC）结构的VAlTiCrW高熵合金薄膜。发现 VALTiCrW 薄膜在 800 °C 下表现出非常低的 0.15 摩擦系数和 10 ^{-5个数量级的低磨损率。}800℃氧化后，薄膜在700℃时仍能获得不大于0.2的摩擦系数。XRD和TEM揭示了三元氧化物AlV ₃ O _9的形成（002）晶面在薄膜磨损面上具有0.71nm大间距的择优取向，一种尚未报道的高温润滑相，实现了低摩擦系数。这种AlV ₃ O ₉可以在700 ℃的热机械作用下通过摩擦化学反应形成，但800 ℃的预氧化是形成富V和富Al氧化物层前驱体的先决条件。