Effects of Environmental Gas and Trace Water on the Friction of DLC Sliding with Metals

Micromachines

Yoshihiro Kurahashi¹  Hiroyoshi Tanaka²  Masaya Terayama²  Joichi Sugimura³ 

[1] Department of Hydrogen Energy Systems, Graduate School of Engineering, Kyushu University, Fukuoka 819-0395, Japan;Department of Mechanical Engineering, Kyushu University, Fukuoka 819-0395, Japan;Research Center for Hydrogen Industrial Use and Storage, Kyushu University, Fukuoka 819-0395, Japan;

关键词: DLC;    friction;    gas;    trace water;    aluminum;    FT-IR;    laser Raman spectroscopy;   

DOI  :  10.3390/mi8070217

来源: DOAJ

【 摘 要 】

This paper describes an experimental study on the friction of a-C:H diamond-like carbon (DLC) and ta-C DLC coatings in gas with different concentration of trace water. Pin-on-disk sliding experiments were conducted with DLC coated disks and aluminum pins in hydrogen, nitrogen, and argon. Trace oxygen was eliminated to less than 0.1 ppm, while water in the gas was controlled between 0 and 160 ppm. Fourier transform infrared spectroscopy (FT-IR) and laser Raman spectroscopy were used to analyze the transfer films on the metal surfaces. It was found that trace water slightly increased friction in hydrogen gas, whereas trace water caused a significant decrease in the friction coefficient in nitrogen and argon, particularly with a-C:H DLC. The low friction in hydrogen was brought about by the formation of transfer films with structured amorphous carbon, but no differences in the structure and contents of the films were found in the tests with and without trace water. In nitrogen and argon, the low friction with a-C:H DLC was achieved by the gradual formation of transfer films containing structured amorphous carbon, and FT-IR spectra showed that the films contained CH, OH, C–O–C, and C–OH bonds.

【 授权许可】

Unknown