Preparation of friction-free, multilayer DLC coatings

2014 Fiscal Year Final Research Report

• Project/Area Number: 26630033
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Design engineering/Machine functional elements/Tribology
• Research Institution: The University of Tokyo
• Principal Investigator: KATO Takahisa 東京大学, 工学(系)研究科(研究院), 教授 (60152716)
• Project Period (FY): 2014-04-01 – 2015-03-31
• Keywords: トライボロジー / ダイヤモンドライクカーボン / 積層膜 / フリクションフリー / フリクションフェイドアウト / イオン化蒸着法

Outline of Final Research Achievements

(sp2)/(sp3) ratio can be controlled by changing the hydrogen contents in diamond-like carbon (DLC)
Film. Using this, the project was conducted for the purpose of preparing multilayer DLC film exhibiting ultralow friction coefficient. Thickness of each layer was several nanometers. The film was prepared by vapor deposition method where hydrocarbon molecules are ionized by thermal electrons and pulled by negative bias voltage. Lower the absolute value of bias voltage, hydrogen contents can be increased. The layers of sp2-rich DLC film of 7.7 nm and sp3-rich DLC film of 7.0 nm are produced on Si substrate one after another. The friction tests show that the multilayer film exhibits the friction coefficient of 10-4, which we call friction fade-out (FFO).

Free Research Field

トライボロジー