本研究目的在探討石墨烯添加至不同潤滑油對磨潤性能的改善情形，分別將不同濃度的石墨烯添加至針車油(Spindle Oil, SP)、聚烷基二醇合成油(Poly Alkylene Glycol, PAG)、礦物油(Mineral Oil, MN)中製成試驗用之混合油。在不同油溫及磨耗週期分別進行往復式與四球迴轉式之滑動磨耗試驗，以試片磨痕大小評估試驗用油之磨潤性能。此外，在針車油中添加分散劑用以探討分散劑對石墨烯分散穩定性之效果。並比較磷系極壓添加劑與石墨烯的耐極壓能力，並且探討此二種添加劑的相容性。其中，不同層數石墨烯對潤滑油磨潤性能的影響亦將詳細分析。
實驗結果顯示，添加適當濃度的石墨烯能有效改善潤滑油之磨潤性能，且於高油溫環境(100℃)下較為顯著。相反地在油溫較低(40℃)時，潤滑油黏度高，較易因油阻效應(Oil Clogging Effect)導致較高的磨耗量。並且，石墨烯濃度過高時較易結團而堵在進油口導致油阻現象，造成嚴重的磨耗行為。長週期的磨耗測試，發現石墨烯於針車油中可能因團聚行為而明顯衰退，並且添加適當濃度之分散劑可以抑制石墨烯之團聚現象，使其磨潤性能的衰退行為減緩。

The purpose of this study is to explore the improvable effect of the tribological performance of graphene added to different lubricants. Different concentrations graphene blended with various based oils, such as spindle oil (SP), poly alkylene glycol (PAG), and mineral oil (MN), individually, to make the test mixed oils. Wear test was individually conducted by reciprocating or four-ball rotary sliding methods at different oil temperatures and duration of wear test to evaluate the tribological performance of the mixed oils based on the size of the wear scar. In addition, a dispersant was added to the spindle oil to investigate the effect of the dispersant on graphene dispersion stability. Additionally, the extreme pressure performance of phosphorous based extreme pressure additives was compared with the graphene, and then the compatibility of these two additives was explored. Among them, the influence of the graphene with different layers on the lubricating oil tribological performance was also analyzed in detail.
The experimental results showed that adding appropriate concentration of the graphene to the oil could effectively improve the tribological performance of the mixed oil, and the improving effect was more significant in a high oil temperature environment (100℃). Conversely, when the oil temperature is low (40℃), the viscosity of the lubricating oil is high that made higher probability to cause serious wear due to the oil clogging effect. In addition, when the concentration of graphene in the oil was too high, the graphene was easier to agglomerate, and then block at the oil inlet, causing serious wear behavior by oil clogging effect. Long-period wear test found that the tribological performance of graphene might decay due to agglomeration behavior of graphene in spindle oil. A proper concentration of dispersant added to the mixed oil could inhibit the agglomeration of graphene and slow down its tribological performance declining behavior.

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