本論文使用分子動力學模擬邊界潤滑狀態下不同潤滑劑含石墨
烯之磨潤行為。並且針對不同分子鏈長的潤滑劑中含不同層數的石墨
烯對磨潤行為的影響進行分析。此外，探討不同層數的石墨烯在不同
的溫度和負載下對磨潤性能的影響。並且，探討石墨烯長度對於磨潤
性能的影響。
結果顯示在未加入石墨烯的條件下，試片進行相對滑動時，
C32H66潤滑劑具有較佳的磨潤行為。烷烴分子隨著分子鏈長越長，黏
度越高，使得潤滑劑之承載能力較好，促使粗糙峰(asperity)的干涉量
降低，具有較佳的磨潤性能。
在相同負載下，含有四層石墨烯的潤滑劑，在摩擦過程中滑動面
之間的間隙相對較大，石墨烯較易進入粗糙峰之間，後續滑動過程的
剪切行為則發生在四石墨烯的層與層之間，使摩擦力明顯減小而有較
好的磨潤行為。
油溫較高時，潤滑劑的黏度和承載能力均下降，導致粗糙峰的干
涉量增加，使磨潤性能下降。較長的石墨烯在潤滑劑中，所承受潤滑
劑流動所產生的拖曳力增加，較易進入粗糙峰之間，防止粗糙峰直接
接觸，避免磨潤行為加劇，能提升磨潤性能。負載較低時含石墨烯潤
滑劑，因上下粗糙峰之間的間隙較大，粗糙峰的干涉量較小，使得摩
擦阻抗下降。

In this paper, molecular dynamics is used to simulate the grinding
behavior of graphene in different lubricants under boundary lubrication.
And the influence of graphene with different layers in different lubricants
on the grinding behavior was analyzed. In addition, the effects of different
layers of graphene on the grinding performance at different temperatures
and loads were explored. Furthermore, the effect of graphene length on the
grinding performance was investigated.
The results show that the C32H66 lubricant has better grinding behavior
when the test piece slides relatively without adding graphene. The longer
the hydrocarbon chain length is, the higher the viscosity, which makes the
bearing capacity of the lubricant better, reduces the interference amount of
the rough peak, and has better grinding performance.
Under the same load, for the lubricant containing four-layer graphene,
the gap between the sliding surfaces is relatively large during the friction
process, and the graphene is easier to enter between the rough peaks, and
the shear behavior of the subsequent sliding process occurs in the fourgraphene Between the layers, the friction force is significantly reduced and
there is a better grinding behavior.
When the oil temperature is higher, the viscosity and load-carrying
capacity of the lubricant decrease, resulting in an increase in the amount of
interference of the asperity peaks and a decrease in the lubricating
performance. Longer graphene in the lubricant increases the drag force
generated by the flow of the lubricant, and it is easier to enter between the
rough peaks, preventing the direct contact between the rough peaks,
avoiding the aggravation of the grinding behavior, and improving the
grinding performance. When the load is low, the graphene lubricant
contains a large gap between the upper and lower rough peaks, and the
interference amount of the rough peaks is small, which reduces the friction
resistance.
Keywords:Molecular Dynamics, Graphene, Hydrocarbon chain,
Adhesion-slip, Boundary Lubrication

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