TC11合金表面MLG/Fe2O3纳米颗粒摩擦层的稳定性

使用MPX-2000型摩擦磨损实验机对TC11合金在不同载荷和纳米润滑材料条件下进行摩擦磨损实验。使用SEM、EDS、XRD等手段对其磨损表面和剖面的形貌、成分、结构进行了对比观察和分析。结果表明:将不同种类的纳米材料添加到摩擦副的滑动界面,在TC11合金磨损表面均能形成纳米颗粒摩擦层,摩擦层的稳定性取决于其组成和各组分的含量。只含MLG的摩擦层因承载能力差而具有较低的稳定性,极易破坏。只含Fe2O3的摩擦层在低载时稳定性较高,能减少磨损但是不能降低摩擦。同时含MLG和Fe2O3的双层摩擦层兼具良好的润滑性和承载能力,稳定性强,使TC11合金的摩擦磨损性能显著提高。添加富Fe2O3纳米复合材料的双层MLG/Fe2O3纳米颗粒摩擦层具有更高的稳定性,能更有效地提高钛合金的摩擦学性能。

Stability of MLG/Fe2O3 Nano-particulate Tribo-layer on TC11 Ti-alloy

The tribological behavior of TC11 Ti-alloy was studied via an MPX-2000 type friction and wear tester with TC11Ti-alloy as pin and GCr15 steel as disc in conditions of applying different loads and incorporating various nano-lubricants onto the interface of pin/disc. The surface morphology, cross-section morphology, composition and structure of worn TC11 Ti-alloy were comparatively characterized by means of scanning electron microscopy with energy dispersive spectroscope and X-ray diffractometer. The results show that tribo-layer of nano-particulates could form on the worn surface of TC11 Ti-alloy when different type of nanomaterials were incorporated onto the sliding interface of the tribo-pairs. The stability of the tribo-layer depends on its composition and the relative content of each component. The multi-layered graphene (MLG) containing tribo-layer possessed poor stability and readily damaged because of its low load-bearing capacity. The Fe₂O₃ containing tribo-layer possessed good stability under lower loads, resulting in the reduced wear and increased friction. The double-layered tribo-layer composed simultaneously of MLG and Fe₂O₃ possessed high stability, which can be ascribed to the good lubrication and load-bearing capacity. As a result, the friction and wear performance of TC11 Ti-alloy was markedly enhanced. Especially the double-layered MLG/Fe₂O₃ nano-particulate tribo-layer with Fe₂O₃-rich nanocomposite possessed higher stability and thus the tribological properties of TC11 Ti-alloy could be much effectively improved.