Categorization of Boundary Layers Formed by Adsorption of a Couple of Additives and Its Tribological Property

2019 Fiscal Year Final Research Report

• Project/Area Number: 17H03167
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Design engineering/Machine functional elements/Tribology
• Research Institution: Kyoto University (2019); Doshisha University (2017-2018)
• Principal Investigator: Tomoko Hirayama 京都大学, 工学研究科, 教授 (00340505)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: トライボロジー / 潤滑 / 複数添加剤 / 固液界面分析

Outline of Final Research Achievements

Categorization of boundary layers formed by MoDTC and organic friction modifier (OFM) was examined from the viewpoint of the interfacial structure. In addition, their nanotribological properties were evaluated by atomic force microscopy with colloidal probe. The obtained results showed that OFM was made condensing at the interface by the existence of MoDTC, and that the coefficient of friction was the lowest when the OFM was mixed with MoDTC in lubricant. A series of experiments proved that the formation of thick and sustainable boundary layer is important, resulting in the lower coefficient of friction by a new mechanism.

Free Research Field

トライボロジー

Academic Significance and Societal Importance of the Research Achievements

形成される厚く密度の高い境界潤滑層がどのような化学構造および形態となっているのかに関しては多少疑問が残るものの、実摺動系における更なる摩擦低減への新規的なアプローチとして極圧剤と油性剤の併用が有効であることを界面構造および力学特性の両者から示すことができた。現在、さまざまな機器で同様となる極圧剤と油性剤の併用が検討されており、そのさきがけとなる実験結果の創出に成功したことから、今後、本研究の結果に即した添加剤の併用事例はますます増えるであろうことが期待できる。