Effects of Mechanical and Structural Properties in Plane on Fatigue Strength of DLC Films -For Super Long Life-

• Project/Area Number: 18K03906
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 18040:Machine elements and tribology-related
• Research Institution: Doshisha University (2019-2020); Kyoto Institute of Technology (2018)
• Principal Investigator: Nakamura Morimasa 同志社大学, 理工学部, 准教授 (00464230)
• Co-Investigator(Kenkyū-buntansha): 小畠 淳平 地方独立行政法人大阪産業技術研究所, 和泉センター, 主任研究員 (00566424)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2020: ¥390,000 (Direct Cost: ¥300,000、Indirect Cost: ¥90,000); Fiscal Year 2019: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2018: ¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000)
• Keywords: 硬質皮膜 / ドライコーティング / 力学特性 / 破壊 / DLC / 強度 / ラマン / 物性

Outline of Final Research Achievements

This research aimed to obtain information about deposition of Diamond-Like (DLC) films having higher fatigue strength. So that, mechanical and the other properties of DLC films were investigated. 3 types of cyclic indentation test rigs were developed, second one was improved to solve some problems of first one, and third one was fabricated to indent with much higher frequency using the Langevin type ultrasonic transducer.
In the indentation impression generated by the cyclic indentation tests, Raman spectroscopy was carried out to various locations in the impressions. And intensity ratio of D peak to G peak and G peaks shift were investigated. As a result, it was found that there are a certain area in that diagram where damaged films in this area could be evaluated as fine and could be used.

Academic Significance and Societal Importance of the Research Achievements

DLC膜の疲労強度と，膜に内在する力学的特性，物性の分布との相関性に着目したことが独自性である．この取り組みはDLC膜のみならず多くの硬質皮膜種にも有益な知見を与えると考えている．一方，将来，他種の皮膜において長寿命，高疲労強度を有する硬質皮膜が開発された場合にも，10の7乗回を超えるいわゆる超寿命領域での損傷形態を把握できる試験法が必要になる．このことから先行して試験法，評価法に着眼し，開発しておくことは独創的であり，学術的ばかりでなく工業的，社会的にも大きな波及効果が期待できる．

Research Products

• [Journal Article] Relationships between Raman parameters obtained from cyclic indentation impressions on DLC coatings (2020)
  • Author(s): Takagawa Yuka、Nakamura Morimasa、Miura Ken‐ichi、Kobata Junpei
  • Journal Title: Surface and Interface Analysis Volume: 2020 Issue: 12 Pages: 1-5
  • DOI: 10.1002/sia.6780
  • Peer Reviewed
• [Presentation] ボイスコイルモータを用いたDLC膜の繰返し押付け試験機の開発および圧痕の評価 (2021)
  • Author(s): 木村一貴，中村守正，松岡敬
  • Organizer: 日本機械学会関西支部第96期定時総会講演会（オンライン）
• [Presentation] ボイスコイルモータを用いたDLC膜の繰返し押付け試験機の開発 (2020)
  • Author(s): 木村一貴，中村守正，松岡敬
  • Organizer: 第22回関西表面技術フォーラム（オンライン）
• [Presentation] 超音波振動子を用いたギガサイクル繰返し押付け試験機によるDLC膜の損傷評価 -損傷形態に及ぼす成膜条件の影響- (2020)
  • Author(s): 山元拓真，中村守正，松岡敬，三浦健一，小畠淳平
  • Organizer: 第22回関西表面技術フォーラム（オンライン）
• [Presentation] 超音波振動子を用いたギガサイクル繰返し押付け試験によるDLC 膜の損傷評価 (2020)
  • Author(s): 山元拓真，中村守正，松岡敬
  • Organizer: 2020年度砥粒加工学会学術講演会，秋田（オンライン）
• [Presentation] Relationships between Raman parameters obtained from cyclic indentation impressions on DLC coatings (2019)
  • Author(s): Takagawa Yuka、Nakamura Morimasa、Miura Ken‐ichi、Kobata Junpei
  • Organizer: 18th European Conference on Applications of Surface and Interface Analysis
  • Int'l Joint Research
• [Presentation] 繰り返し球圧子押し付け後のDLC膜構造変化 (2018)
  • Author(s): 髙川祐加，中村守正
  • Organizer: 日本塑性加工学会関西支部 平成 30 年度 関西支部 若手技術交流会 兼 関西支部 第 36 回先端塑性加工技術コロキウム