The purpose of this study was to investigate the influence of solid lubricants on the friction and wear behavior of Cu-based thermal-sprayed coatings. The ultimate goal was to identify the friction coefficient behavior of these systems as well as establish an understanding of the interfacial processes. Experiments were conducted using a flat-on-flat apparatus with uncoated pins against Cu-based thermal-sprayed systems with and without molybdenum disulfide (MoS 2 ) as the solid lubricant. The results showed that the coefficient of friction for the samples with Cu-Al was similar to that of the uncoated system. The unlubricated systems (i.e., Cu-Al coated and uncoated) showed higher friction values compared with the one with the MoS 2 lubricant. Additional testing with re-application of the MoS 2 lubricant was also performed and overall showed the lowest steady-state friction. The wear behavior of the different configurations correlated well with the friction coefficient observations. In addition, ex situ cross-sectional analysis by means of focused ion beam/scanning electron microscopy was performed to capture the third body phenomena and explain the difference in the friction and wear behavior.

中文翻译：

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深入了解极端接触条件下铜基涂层的摩擦学特性

本研究的目的是研究固体润滑剂对铜基热喷涂涂层摩擦磨损行为的影响。最终目标是确定这些系统的摩擦系数行为，并了解界面过程。使用带有无涂层针的平对平装置对有和没有二硫化钼 (MoS 2 ) 作为固体润滑剂的铜基热喷涂系统进行实验。结果表明，Cu-Al 样品的摩擦系数与未涂层系统的摩擦系数相似。与使用 MoS 2 润滑剂的系统相比，未润滑系统（即，Cu-Al 涂层和未涂层​​）表现出更高的摩擦值。还进行了重新应用 MoS 2 润滑剂的额外测试，总体上显示出最低的稳态摩擦。不同配置的磨损行为与摩擦系数观察结果密切相关。此外，通过聚焦离子束/扫描电子显微镜进行非原位横截面分析以捕获第三体现象并解释摩擦和磨损行为的差异。