Abstract No single lubricant can provide effective lubrication in various environments. In this study, both graphene (RGO) and WS2 were added to the Cu matrix to prepare self-lubricating composites that can adapt to different environments. Three kinds of Cu-based composites containing different volume ratios of lubricants were fabricated by a hot-pressing method. The physical and mechanical properties of the composites were measured. The tribological behaviors of the composites were tested using a ring-on-disc wear tester in air and vacuum environments. Scanning electron microscopy, 3D laser scanning confocal microscopy, and X-ray photoelectron spectroscopy were used to characterize the worn surface of the composites. Monolayer RGO was prepared, and the ID/IG ratio of RGO was 0.85. The fabricated composites were mainly a mechanical mixture of Cu/RGO/WS2. The total volume of lubricant was constant in the composites, and the hardness increased and thermal conductivity decreased with increasing volume ratio of WS2 to RGO. In air, Cu-RGO exhibited the lowest friction coefficient and wear rate, and Cu-WS2 showed the highest. In a vacuum, Cu-WS2 demonstrated the lowest friction coefficient and wear rate, whereas Cu-RGO was worn through. RGO played the lead role in wear reduction and self-lubrication in air, whereas WS2 was dominant in a vacuum. Cu-RGO-WS2 had greater potential applications due to its low sensitivity to different environments.

中文翻译：

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Cu/RGO/WS2复合材料在空气和真空环境中的摩擦学行为

摘要 没有一种润滑剂可以在各种环境下提供有效的润滑。在这项研究中，石墨烯 (RGO) 和 WS2 都被添加到 Cu 基体中，以制备能够适应不同环境的自润滑复合材料。采用热压法制备了三种含有不同体积比润滑剂的铜基复合材料。测量了复合材料的物理和机械性能。在空气和真空环境中使用环盘磨损测试仪测试复合材料的摩擦学行为。扫描电子显微镜、3D 激光扫描共聚焦显微镜和 X 射线光电子能谱被用来表征复合材料的磨损表面。制备单层RGO，RGO的ID/IG比为0.85。制造的复合材料主要是 Cu/RGO/WS2 的机械混合物。复合材料中润滑剂的总体积不变，随着WS2与RGO体积比的增加，硬度增加，导热系数降低。在空气中，Cu-RGO 表现出最低的摩擦系数和磨损率，而 Cu-WS2 表现出最高。在真空中，Cu-WS2 表现出最低的摩擦系数和磨损率，而 Cu-RGO 被磨损。RGO 在空气中减少磨损和自润滑方面起主导作用，而 WS2 在真空中起主导作用。Cu-RGO-WS2由于其对不同环境的敏感性较低而具有更大的潜在应用。Cu-RGO 表现出最低的摩擦系数和磨损率，Cu-WS2 表现出最高。在真空中，Cu-WS2 表现出最低的摩擦系数和磨损率，而 Cu-RGO 被磨损。RGO 在空气中减少磨损和自润滑方面起主导作用，而 WS2 在真空中起主导作用。Cu-RGO-WS2由于其对不同环境的敏感性较低而具有更大的潜在应用。Cu-RGO 表现出最低的摩擦系数和磨损率，Cu-WS2 表现出最高。在真空中，Cu-WS2 表现出最低的摩擦系数和磨损率，而 Cu-RGO 被磨损。RGO 在空气中减少磨损和自润滑方面起主导作用，而 WS2 在真空中起主导作用。Cu-RGO-WS2由于其对不同环境的敏感性较低而具有更大的潜在应用。