Application of ta-C Coating on WC Mold to Molded Glass Lens
1
조회
0
다운로드
3
인용
0
참고문헌
키워드
초록
We investigated the application of tetrahedral amorphous carbon (ta-C) coatings to fabricate a glass lens manufactured using a glass molding process (GMP). In this work, ta-C coatings with different thickness (50, 100, 150 and 200 nm) were deposited on a tungsten carbide (WC-Co) mold using the X-bend filter of a filtered cathode vacuum arc. The effects of thickness on mechanical and tribological properties of the coating were studied. These ta-C coatings were characterized by atomic force microscopy, scanning electron microscopy, nano-indentation measurements, Raman spectrometry, Rockwell-C tests, scratch tests and ball on disc tribometer tests. The nano-indentation measurements showed that hardness increased with an increase in coating thickness. In addition, the G-peak position in the Raman spectra analysis was right shifted from 1520 to 1586 cm−1, indicating that the sp3 content increased with increasing thickness of ta-C coatings. The scratch test showed that, compared to other coatings, the 100-nm-thick ta-C coating displayed excellent adhesion strength without delamination. The friction test was carried out in a nitrogen environment using a ball-on-disk tribometer. The 100-nm-thick ta-C coating showed a low friction coefficient of 0.078. When this coating was applied to a GMP, the life time, i.e., shot counts, dramatically increased up to 2,500 counts, in comparison with Ir-Re coating.
Abstract
We investigated the application of tetrahedral amorphous carbon (ta-C) coatings to fabricate a glass lens manufactured using a glass molding process (GMP). In this work, ta-C coatings with different thickness (50, 100, 150 and 200 nm) were deposited on a tungsten carbide (WC-Co) mold using the X-bend filter of a filtered cathode vacuum arc. The effects of thickness on mechanical and tribological properties of the coating were studied. These ta-C coatings were characterized by atomic force microscopy, scanning electron microscopy, nano-indentation measurements, Raman spectrometry, Rockwell-C tests, scratch tests and ball on disc tribometer tests. The nano-indentation measurements showed that hardness increased with an increase in coating thickness. In addition, the G-peak position in the Raman spectra analysis was right shifted from 1520 to 1586 cm−1, indicating that the sp3 content increased with increasing thickness of ta-C coatings. The scratch test showed that, compared to other coatings, the 100-nm-thick ta-C coating displayed excellent adhesion strength without delamination. The friction test was carried out in a nitrogen environment using a ball-on-disk tribometer. The 100-nm-thick ta-C coating showed a low friction coefficient of 0.078. When this coating was applied to a GMP, the life time, i.e., shot counts, dramatically increased up to 2,500 counts, in comparison with Ir-Re coating.
참고문헌 (21)
- Park, J. H., "Tribological characteristics of DLC film using substrates with varying hardness", KSTLE International Journal, 9(1, pp.2) (2008), 31~35
- 장붕, "DLC와 PTFE표면코팅에 따른 자기유변유체의 마찰 마모 특성", 한국트라이볼로지학회지, 31(2), pp.62~68 (2015), 한국트라이볼로지학회[DOI]
- Fischbacha, Kyle, D., "Investigation of the effects of process parameters on the glass-to-mold sticking force during preci-sion glass molding", Surf. Coatings Technol., 205(2), pp.312~319 (2010)
- Ananthasayanam, B., "High temperature friction characterization for viscoelas-tic glass contacting a mold", J. Non. Cryst. Solids, 385, pp.100~110 (2014)
- Klocke, F., "Adhesive interlayers’effect on the entire structure strength of glass mold-ing tools’ Pt-Ir coatings by nano-tests determined", Surf. Coatings Technol., 206(7), pp.1867~1872 (2011)
- Shi, X, "Fil-tered cathodic arc source", Filpas Vacuum Technol-ogy Pte Ltd., US Patent No. 6031239, ~
- Kang, M. C., "Properties and tool performance of ta-C films deposited by double-bend filtered cathode vacuum arc for micro drilling applications", Diam. Relat. Mater., 19(7-9), pp.866~869 (2010)
- Min Szan Lim, "Investigation of Friction and Wear of Tetrahedral Amorphous Carbon (ta-C) Coating with Various Counterpart Materials", 한국트라이볼로지학회지, 34(6), pp.241~246 (2018), 한국트라이볼로지학회[DOI]
- 장영준, "DLC (ta-C) 후막코팅을 위한 트라이볼로지 코팅 연구", 한국트라이볼로지학회지, 32(4), pp.125~131 (2016), 한국트라이볼로지학회[DOI]
- Wang, C. T., "Indenta-tion and scratch testing of DLC-Zr coatings on ultrafine-grained titanium processed by high-pres-sure torsion", Wear, 306(1-2), pp.304~310 (2013)
- Masami, I., "Eva-luation of elastoplastic properties DLC coating on SKD61 steel by optical indentation microscopy", Surf. Coatings Technol., 203(17-18), pp.2571~2574 (2009)
- Wei, Q., "Mech-anical properties of diamond-like carbon composite thin films prepared by pulsed laser deposition", Com-pos. Part B Eng., 30(7), pp.675~684 (1999)
- Silva, S., "Amorphous carbon: State of the art. In Amorphous Carbon: State of the Art", pp.1~374 (1998), World Scien-tific
- Teo, K. B. K., "Effect of gra-phitic inclusions on the optical gap of tetrahedral amorphous carbon films", J. Appl. Phys., 89(7), pp.3706~3710 (2001)
- Peng, X., "Surface roughness of diamond-like carbon films prepared using vari-ous techniques", Surf. Coatings Technol., 138(1), pp.23~32 (2001)
- Li, X., "Fracture mechan-isms of thin amorphous carbon films in nanoinden-tation", Acta Mater., 45(11), pp.4453~4461 (1997)
- 이준혁, "강체인 구와 DLC 코팅면 사이의 압입 및 미끄럼 접촉해석: 지지층 두께의 영향", 한국트라이볼로지학회지, 30(4), pp.199~204 (2014), 한국트라이볼로지학회[DOI]
- Robertson, J., "Diamond-like amorphous carbon", Sci. Eng. R Reports, 37(4-6), pp.129~281 (2002)
- Roch, T., "Direct laser interference patterning of tetrahedral amorphous carbon films for tribologi-cal applications", Diam. Relat. Mater., 33, pp.20~26 (2013)
- Beake, B. D., "Nano-scratch, nano-indentation and fretting tests of 5-80 nm ta-C films on Si (100)", Wear, 301(1-2), pp.575~582 (2013)
- Cha, D. H., "Effect of tem-perature on the molding of chalcogenide glass lenses for infrared imaging applications", Appl. Opt., 49(9), pp.1607~1613 (2010)