The Tribological Behaviors of Self-Lubricating Composites as Filler in Copper Foam

A copper foam-based (CFB) self-lubricating composite was developed as a friction pair material. The composite consists of copper foam with three-dimensionally interpenetrated pores and solid lubricant fillers (polytetrafluoroethylene [PTFE] and MoS2). The thermal and electrical conductivity, bending strength, and tribological properties of the new composite were investigated. The friction and wear properties were investigated on a M-2000 model ring-on-block test rig. An electric field was imposed between the sample and ring to monitor the tribochemical reaction and formation of transfer film by means of contact resistance. Measurement of friction temperature was carried out by means of three thermocouples embedded in the material. The friction coefficients of the CFB composite decrease slightly, and the wear rate substantially decreased overall compared with that of the homologous polymers. The optical and scanning electronmicrographs (SEM) of the frictional surfaces show the worn surface of the CFB composite. The main wear mechanism was three-body abrasion, caused and promoted by plastic deformation, abrasive wear, and fatigue spalling. X-ray photoelectron spectroscopy (XPS) analysis showed that the reactions of MoS2 with Cu accompanied by their respective oxidation reactions are involved in the identifiable copper area.

开发了一种基于泡沫铜（CFB）的自润滑复合材料作为摩擦副材料。该复合材料由具有三维相互贯通孔隙的泡沫铜以及固体润滑剂填料（聚四氟乙烯[PTFE]和二硫化钼[MoS2]）组成。对这种新型复合材料的热导率、电导率、抗弯强度和摩擦学性能进行了研究。在M - 2000型环 - 块试验台上研究了其摩擦磨损性能。在样品和环之间施加电场，通过接触电阻来监测摩擦化学反应以及转移膜的形成。通过嵌入材料中的三个热电偶来测量摩擦温度。与同类聚合物相比，CFB复合材料的摩擦系数略有降低，总体磨损率大幅下降。摩擦表面的光学显微镜照片和扫描电子显微镜照片（SEM）显示了CFB复合材料的磨损表面。主要磨损机制是三体磨损，由塑性变形、磨粒磨损和疲劳剥落引起并促进。X射线光电子能谱（XPS）分析表明，在可识别的铜区域涉及二硫化钼与铜的反应以及它们各自的氧化反应。