New Droplet Removal Polishing Method for Diamond-Like Carbon with Carbon Fiber Brush
Motoyuki Murashima, Yusuke Imaizumi, Noritsugu Umehara, and Takayuki Tokoroyama
Department of Micro-Nano Mechanical Science and Engineering, Graduate School of Engineering, Nagoya University
Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
In this paper, we propose a new polishing method for diamond-like carbon (DLC) coatings using a carbon fiber brush (CFB). Surface finishing is an important process for DLC coating applications. A lapping process is widely used for attaining tetrahedral amorphous carbon (ta-C) coatings, which are a type of DLC coating containing many droplets, to obtain fine flat surfaces. The lapping process removes protuberant parts of droplets rather than the entire droplet. In this paper, we propose a new polish brush material made of carbon fiber, called CFB. Carbon fiber has both mechanical strength due to its hard carbonaceous material and flexibility due to its fiber structure. In polishing tests, CFB removed droplets from ta-C coatings and the removal effect increased with the shortening of the brush length. The surface profiles of the polished surfaces indicated that a shorter brush length yielded deep scratch marks on ta-C surfaces. Consequently, the arithmetic average surface roughness of the polished ta-C surfaces, Sa, had almost the same value as that of a non-polished surface. Here, we show the ability of CFB to remove the droplets without an increase in the surface roughness. The CFB with the longest brush length in the present study (12 mm) showed a ten-point average roughness SZJIS= 75 nm and Sa= 4.7 nm, which were 59% and 22% lower than those of the non-polished surface, respectively. Furthermore, the longest CFB removed the entire droplets whereas a shorter CFB merely removed the protuberant part of the droplets. The result indicates that CFB polishing can remove entire droplets, which result in abrasive wear or deterioration. From other polishing tests, the optimum polishing distance was determined. Shorter polishing distances could not remove droplets sufficiently whereas longer polishing distances caused deep scratches on ta-C surfaces due to the material transferred to the CFB. Accordingly, the polishing distance of 600 m showed the best surface finishing with SZJIN= 25 nm and Ra= 0.43 nm, which were 86% lower than and similar to those of the non-polished ta-C surface, respectively.
-  A. Erdemir and C. Donnet, “Tribology of diamond-like carbon films: recent progress and future prospects,” J. Phys. D: Appl. Phys., Vol.39, pp. 311-327, 2006.
-  C. Donnet, “Recent progress on the tribology of doped diamond-like carbon alloy coatings: a review,” Surf. & Coat. Technol., Vols.100-101, pp. 180-186, 1998.
-  A. Erdemir, “The role of hydrogen in tribological properties of diamond-like carbon films,” Surf. & Coat. Technol., Vols.146-147, pp. 292-297, 2001.
-  M. Sonobe, “Application of DLC coatings to dry cutting tools,” Tribologist, Vol.47, pp. 827-832, 2002 (in Japanese).
-  M. Kano, “Diamond-like carbon coating applied to automotive engine components,” Tribology Online, Vol.9, pp. 135-142, 2014.
-  Y. Mabuchi, “Application of DLC coatings on automotive parts,” Tribologist, Vol.58, pp. 557-565, 2013 (in Japanese).
-  Y. Mabuchi, T. Yamashita, H. Izumi, T. Sekikawa, K. Nishimura, S. Hirano, and Y. Moriguchi, “Examination of the axial shape of the automotive valvetrain cam for engine friction reduction,” Tribology Trans., Vol.60, pp. 1088-1098, 2017.
-  T. Higuchi, Y. Mabuchi, H. Ichihara, T. Murata, and M. Moronuki, “Development of hydrogen-free diamond-like carbon coating for piston rings,” Tribology Online, Vol.12, pp. 117-122, 2017.
-  Y. Mabuchi, T. Higuchi, and V. Weihnacht, “Effect of sp2/sp3 bonding ratio and nitrogen content on friction properties of hydrogen-free DLC coatings,” Tribology Int., Vol.62, pp. 130-140, 2013.
-  H. Takikawa, K. Izumi, R. Miyano, and T. Sakakibara, “DLC thin film preparation by cathodic arc deposition with a super droplet-free system,” Surf. & Coat. Technol., Vol.163, pp. 368-373, 2003.
-  H. Takikawa, “Coating Technology of Droplet-free High-quality DLC Film by Filtered Arc Ion Plating,” J. Surf. Finishing Soc. Jpn., Vol.58, pp. 572-577, 2007 (in Japanese).
-  Y. Mabuchi, T. Higuchi, Y. Inagaki, H. Kousaka, and N. Umehara, “Wear analysis of hydrogen-free diamond-like carbon coatings under a lubricated condition,” Wear, Vol.298, pp. 48-56, 2013.
-  M. Murashima, X. Deng, H. Izuoka, N. Umehara, and H. Kousaka, “Effect of oxygen on degradation of defects on ta-C coatings deposited by filtered arc deposition,” Surf. & Coat. Technol., Vol.362, pp. 200-207, 2019.
-  X. Shi, B. K. Tay, H. S. Tan, E. Liu, J. Shi, L. K. Cheah, and X. Jin, “Transport of vacuum arc plasma through an off-plane double bend filtering duct,” Thin Solid Films, Vol.345, pp. 1-6, 1999.
-  R. L. Boxman, V. Zhitomirsky, B. Alterkop, E. Gidalevich, I. Beilis, M. Keidar, and S. Goldsmith, “Recent progress in filtered vacuum arc deposition,” Surf. & Coat. Technol., Vol.86-87, pp. 243-253, 1996.
-  Y. Fujii, T. Imai, Y. Miyamoto, N. Ueda, M. Hosoo, T. Harigai, Y. Suda, H. Takikawa, H. Tanoue, M. Kamiya, M. Taki, Y. Hasegawa, N. Tsuji, and S. Kaneko, “Dry machining of metal using an engraving cutter coated with a droplet-free ta-C film prepared via a T-shape filtered arc deposition,” Surf. & Coat. Technol., Vol.307, pp. 1029-1033, 2016.
-  A. Anders, “Approaches to rid cathodic arc plasmas of macro- and nanoparticles: a review,” Surf. & Coat. Technol., Vol.120-121, pp. 319-330, 1999.
-  M. Kamiya, T. Yanagita, H. Tanoue, S. Oke, Y. Suda, H. Takikawa, M. Taki, Y. Hasegawa, T. Ishikawa, and H. Yasui, “T-shape filtered arc deposition system with built-in electrostatic macro-particle trap for DLC film preparation,” Thin Solid Films, Vol.518, pp. 1498-1502, 2009.
-  H. Takikawa, “Fabrication of DLC film by filtered arc deposition,” J. Plasma Fusion Res., Vol.92, pp. 466-471, 2016.
-  A. Leson, G. Englberger, D. Hammer, S. Makowski, C.-F. Meyer, M. Leonhard, H.-J. Scheibe, and V. Weihnacht, “Diamond-like carbon thin films enhance efficiency – laser arc deposition of ta-C,” Vakuum, Vol.27, pp. 24-28, 2015.
-  M.-Y. Tsai, Y.-F. Lin, J.-K. Ho, and J.-G. Yang, “Ultrasonic-Assisted Innovative Polyurethane Tool to Polish Mold Steel,” Int. J. Automation Technol., Vol.13, No.2, pp. 199-206, 2019.
-  Y. Manabe, H. Murakami, T. Hirogaki, E. Aoyama, and T. Furuki, “Mirror-Surface Finishing by Integrating Magnetic-Polishing Technology with a Compact Machine Tool,” Int. J. Automation Technol., Vol.13, No.2, pp. 207-220, 2019.
-  U. Satake, T. Enomoto, T. Miyanaga, T. Ohsumi, H. Nakagawa, and K. Funabashi, “Stabilization of Removal Rate in Small Tool Polishing of Glass Lenses,” Int. J. Automation Technol., Vol.13, No.2, pp. 221-229, 2019.
-  A. Kubota, “Surface finishing of single-crystal SiC and GaN wafers using a magnetic tool in H2O2 solution,” Int. J. Automation Technol., Vol.13, No.2, pp. 230-236, 2019.
-  K. Miyake, “Characteristics and Applications of Diamond Like Carbon (DLC) Films,” J. Vac. Soc. Jpn., Vol.60, pp. 428-436, 2017 (in Japanese).
-  S. Otani, “Tansoshitsuseni,” Tanso, Vol.1967, pp. 32-39, 1967 (in Japanese).
-  T. Shitaka, M. Murashima, N. Umehara, Y. Tsukiyama, I. Nitta, H. Kousaka, and X. Deng, “Proposal of lightweight and low starting torque slide bearing with looped carbon fibers brush,” Trans. JSME, Vol.83, pp. 1-10, 2017 (in Japanese).
-  A. Fukunaga, “CMP souti to electrochemistry,” Electrochemistry, Vol.74, pp. 971-975, 2006 (in Japanese).
-  R. Ozawa, Y. Suzuki, N. Mori, T. Yaguchi, J. Itoh, and S. Yamamoto, “Surface Roughness Evaluation/Power Spectral Density and Slope Histogram,” Surf. Sci., Vol.20, pp. 727-731, 1999 (in Japanese).
-  M. Kato and K. Kutsuzawa, “Fukugouzai (CFRP) oyobi tainetsugoukinn no sessaku kakougijutu,” Jisedai monodukuri kibankakougijutu chousa kakou data syuu, pp. 41-51, 2012 (in Japanese).
-  H. Hanyu, “Diamond Coated Tools for Machining of Lightweight Materials,” J. Surf. Finishing Soci. Japan, Vol.63, pp. 151-156, 2012 (in Japanese).
-  T. Kumagai, “Recent Progress in DLC Coated Cutting Tool,” J. Surf. Finishing Soci. Japan, Vol.51, pp. 250-254, 2000 (in Japanese).
-  X. Huang, “Fabrication and Properties of Carbon Fibers,” Materials, Vol.2, pp. 2369-2403, 2009.
-  X. Li, X. Deng, H. Kousaka, and N. Umehara, “Comparative study on effects of load and sliding distance on amorphoushydrogenated carbon (a-C:H) coating and tetrahedral amorphous carbon (ta-C) coating under base-oil lubrication condition,” Wear, Vols.392-393, pp. 84-92, 2017.
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