Tribological Properties of a Mesh-Like Nanostructured Diamond-Like Carbon (DLC) Lubricated with a Fully Formulated Oil at DLC/Steel Contacts under Boundary Lubrication

Coatings

Shinya Sasaki¹  Seiya Watanabe¹  Daisuke Iba²  Hikaru Okubo²  Ichiro Moriwaki²  Hideki Moriguchi³  Yuuki Tokuta⁴ 

[1] Department of Mechanical Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan;Mechanical Engineering, Kyoto Institute of Technology, Goshokaidou-chou Matsugasaki Sakyo-ku Kyoto, Kyoto 606-8585, Japan;Nippon ITF Corporation, 575, Kuzetonoshirocho, Kyoto Minami-ku, Kyoto 601-8205, Japan;Tokyo Metropolitan Industrial Technology Research Institute, 2-4-10, Aomi, Koto-ku, Tokyo 135-0064, Japan;

关键词: diamond-like carbon;    a-C;    a-C:H;    boundary lubrication;    in situ observation;   

DOI  :  10.3390/coatings11070746

来源: DOAJ

【 摘 要 】

The present paper describes the tribological properties of a mesh-like nanostructure of diamond-like carbon (DLC) in a formulated engine oil at DLC/steel contacts. This novel nanostructured DLC was characterized as a non-hydrogenated amorphous carbon (a-C) with a nano-mesh structure layer at the outermost surface, herein named NM-a-C. From the results of our friction tests, we observed that the NM-a-C/steel tribopair exhibited lower friction and higher wear-resistance than the a-C:H/steel tribopair, though the mechanical properties were nearly identical. The analytical result indicated that the tribofilm formation process and the chemical composition of the tribofilm varied depending on the types of the DLC. In particular, thicker MoS₂-rich tribofilms formed on the NM-a-C surface. Hence, the NM-a-C structure promoted the formation of MoS₂ under the lubrication with the fully formulated oil, leading to lower friction and high wear-resistance at the DLC/steel contact under boundary lubrication conditions.

【 授权许可】

Unknown