Thèses : « DLC »

1

Li, Jingyun. « Lapped transforms based on DLS and DLC basis functions and applications ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ30101.pdf.

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Wong, Chun-ming, et 黃俊銘. « Characterization of novel tumor suppressor genes, DLC-1 and DLC-2, in hepatocellular carcinoma ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B27768533.

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3

Graupner, Karola. « Untersuchungen zur Hochrateabscheidung harter DLC-Schichten ». [S.l. : s.n.], 2005. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB11679790.

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Salgueiredo, Ermelinda da Conceição Portela. « Filmes de DLC para aplicações biotribológicas ». Master's thesis, Universidade de Aveiro, 2007. http://hdl.handle.net/10773/2248.

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Mestrado em Engenharia Biomédica - Biomateriais
Os filmes de carbono amorfo tipo diamante (DLC) actuam como lubrificantes sólidos em muitas aplicações de desgaste incluindo os implantes articulares da anca e joelho. Entre estes, os filmes de carbono não-hidrogenado podem ser depositados pela técnica de deposição física em fase vapor (PVD) a baixas temperaturas (<325ºC). Estes filmes protectores são quimicamente inertes, possuem elevada dureza e baixo coeficiente de atrito contra polietileno de ultra alto peso molecular (UHMWPE) e outros biomateriais, aumentando assim a qualidade dos implantes articulares. Filmes de DLC foram depositados por sputtering DC em substratos à base de nitreto de silício (Si3N4 monolítico; compósitos Si3N4/TiN e Si3N4/bioglass) visando elevados níveis de adesão. A nanoestrutura do DLC, confirmada pela fraca intensidade da banda D do espectro Raman, combinada com o elevado conteúdo de ligações sp3, comprovado pelo desvio da banda G, levou a um valor de dureza de 16 GPa. Os filmes apresentam-se densos e homogéneos com um valor extremamente baixo de rugosidade (RMS=2.6 nm). Antes de ser implantado no corpo humano, um material tem de provar ser biocompatível. Antes da deposição de DLC, os substratos foram recobertos com uma camada de Si para promover a adesão. Após 35 dias de imersão em SBF, a observação SEM demonstrou que não ocorreu formação de camada apatítica na superfície. A análise química por ICP-AES mostrou que não houve variação na concentração dos iões Ca e P, e que não foram libertados elementos tóxicos na solução. A hidrofobicidade, tensão superficial e carga superficial deste biomaterial foram também avaliadas. A superfície apresentou um valor ligeiramente negativo de carga, como demonstrado pelo valor do potencial zeta de -35.0 ± 1.3 mV para pH=7.4 ± 0.2. A tensão superficial foi de 45.7 mN/m, apresentando uma componente dispersiva predominante da tensão superficial. Os resultados mostram que o revestimento de DLC é tendencialmente hidrofóbico. Os estudos com a linha celular de osteoblastos humanos MG63 não revelaram indícios de citotoxicidade. As células apresentaram morfologia normal e maior crescimento celular, quando comparadas com as placas standard de cultura, mostrando, no entanto, menor adesão celular. Para os ensaios biotribológicos, bolas e discos cerâmicos foram recobertos com filmes de DLC numa primeira etapa para ensaios de deslizamento a seco em movimento recíproco, com pares próprios. Um bias negativo foi aplicado ao compósito condutor Si3N4/TiN, resultando em valores de coeficiente de atrito extremamente baixos(μ=0.015). Numa segunda etapa, placas recobertas com DLC foram testadas contra bolas de UHMWPE. Os testes foram efectuados a seco e lubrificado (SBF). Os resultados preliminares mostram que o coeficiente de atrito mantém-se constante ao longo do ensaio, sem delaminação do DLC. Estes resultados favoráveis permitem recomendar o Si3N4 revestido com DLC como adequado para aplicações em próteses articulares. ABSTRACT: Diamond-like carbon (DLC) films act as solid-film lubricants in many wear resistant applications including articulated implants as hip and knee joints. Among these, non-hydrogenated amorphous carbon films can be grown by Physical Vapour Deposition (PVD) technique at low deposition temperatures (<325ºC). These protective coatings possess chemical inertness, high hardness and low friction coefficient against Ultra High Molecular Weight Polyethylene (UHMWPE) and other biomaterials, thereby improving the quality of articulated implants. In this study, the DLC films were deposited by DC magnetron sputtering over silicon nitride based substrates (bulk Si3N4; Si3N4/TiN and Si3N4/bioglass composites) aiming high adhesion levels. DLC nanostructure, confirmed by the weak intensity of the Raman spectra D band position, combined with significant sp3 content, as depicted by the G band downshift, lead to a hardness value of about 16 GPa. Films are dense and homogeneous in all the deposited area with an extremely low roughness of 2.6 nm (RMS). Before implantation in the human body, a material must prove to be biocompatible. Prior to the DLC deposition, the Si3N4 based ceramics were coated with a Si interlayer to promote adhesion. After 35 days of immersion in Simulated Body Fluid, SBF, the DLC surface showed no signs of apatite layer formation, as observed by SEM. Also, ICP-AES analysis confirmed no variation of the Ca and P ions concentration levels, and no toxic elements released into solution were detected. Hydrophobicity, surface tension and surface charge was also evaluated. The DLC surface is slightly negative charged, has shown by the zeta potential value of -35.0 ± 1.3 mV at pH=7.4 ± 0.2. The surface tension of the DLC coated samples was 45.7mN/m, presenting a dominant dispersive component of the surface tension. Results showed that the DLC coating is quite hydrophobic. Using the MG63 osteoblast-like cells, no evidence of citotoxicity was observed. Cells showed normal morphology and higher cell growth, compared to standard culture plates, although with low cell adhesion. For biotribological assessment, in a first stage Si3N4 ceramic balls and discs were coated with DLC films for self-mated reciprocating dry sliding tests. A negative bias voltage applied to a conductive Si3N4/TiN composite showed a remarkable improvement under the same tribological solicitation, presenting very low friction coefficient values (μ=0.015) during the full duration of the test. In a second stage, DLC-coated Si3N4 ceramics were tested against UHMWPE spheres using a reciprocating ball-on-flat set-up. The sliding occurred under dry and lubricated (SBF) conditions. Preliminary results showed that the friction coefficient is almost constant during the running-in period without delamination of the DLC coating. Based in these favourable results, the DLC-coated Si3N4 biomaterial seems adequate to be used for articular prosthesis development.

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Rudolf, Miroslav. « Depozice a analýza tenkých vrstev DLC ». Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2009. http://www.nusl.cz/ntk/nusl-228535.

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Diplomová práce nastiňuje problémy spojené s výrobou a analýzou tenkých vrstev DLC:H. Tyto vrstvy jsou ve středu zájmu mnoha vědeckých pracovníků již po několik desetiletí. V současné době existuje mnoho technik pro přípravu a analýzu. Příprava DLC vrstev má zásadní vliv na jejich vlastnosti a možnosti použití. Je zde mnoho kritérií jak vrstvy posuzovat. V této práci jsou studovány vlastnosti DLC:H vrstev připravených na substrát krystalického křemíku metodou RF-PECVD a následně jsou studovány mechanické, tribologické a optické vlastnosti. Jsou zde využity techniky jako XPS, Ramanova spektroskopie, reflektometrie, měření tvrdosti a adheze. Část práce se zabývá modelováním DLC z prvních principů. Pro tento účel je využito prvoprincipiálního programu Abinit který je šířen pod GPL. Je studována otázka přípravy vstupních dat s ohledem na konvergenci výsledků. Pozornost je také věnována výpočtu vibračních spekter ve středu Brillouinovy zóny ( bod) a celkové hustotě elektronových stavů clusteru DLC v supercele tvaru krychle. Tyto výsledky mohou být porovnány s experimentálně získanými daty z Ramanovy spektroskopie, respektive z XPS spektra valenčního pásu

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Marek, Mojmír. « Optimalizace distribučních cest - DLC Napajedla, a.s ». Master's thesis, Vysoká škola ekonomická v Praze, 2008. http://www.nusl.cz/ntk/nusl-2882.

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Práce má za úkol nastínit možné směry optimalizace rozvrhu distribučních cest. Nástrojem je vhodně konstruovaný model, který se stane součástí aplikace. Aplikace vychází z programů MS Excel a LINGO. Zadání a následné řešení práce má podobu projektu. Předmětem není pouze vytvořit statický model (aplikaci). Práce také vychází z připomínek a požadavků zadavatele.

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Vengudusamy, Balasubramaniam. « Behaviour of lubricant additives on DLC coatings ». Thesis, Imperial College London, 2011. http://hdl.handle.net/10044/1/11734.

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Non-ferrous surfaces such as diamond-like carbon (DLC) coatings are becoming potential candidates for automotive engine parts because of fuel economy gains that these surfaces offer by operating with very low friction. In recent years, a wide range of DLC coatings have been developed and it is important to understand their film-forming, friction reduction and wear resistance mechanisms under lubricated conditions. This aim of the work described in this thesis is to improve our understanding of the tribological behaviour of DLC coatings with different engine oil additives. The main focus of the thesis is to study a wide range of available DLC coating types with currently available and widely-used additives such as ZDDP, friction modifiers, MoDTC etc., in order to establish general rules of their tribological behaviour that will help lubricant manufacturers produce new oil formulations. The research shows that tribofilms are formed on all DLCs by most of the currently used additives and that the film thickness depends on various factors such as type of DLC coating, doping elements present in the coatings, concentration of hydrogen and tungsten present in the coatings and the counterpart. Hydrogen-free coatings (a-C and ta-C) give lower boundary friction compared to the other coatings whereas hydrogenated amorphous carbon (a-C:H) coatings give better wear resistance properties. Study of a-C:H:W coatings shows that the concentration of tungsten present in the coatings has a significant influence on wear resistance properties but negligible influence on the friction properties when additives are present. The steel/steel couple is known to form a thick ZDDP tribofilm. If one of the contact surfaces is coated with DLC, the tribofilm forming properties on the steel vary and, for some cases, the low boundary friction properties of DLCs are degraded.

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Silva, Cruz Ricardo Manuel Santos da. « TiBâ‚‚ ceramic and DLC multilayered PVD coatings ». Thesis, Cranfield University, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443347.

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Santos, da Silva Cruz Ricardo Manuel. « TiB2 ceramic and DLC multilayered PVD coatings ». Thesis, Cranfield University, 2007. http://dspace.lib.cranfield.ac.uk/handle/1826/1863.

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Titanium diboride (TiB2) has been investigated as a potential candidate for several industrial applications, such as: cutting tools, electric devices, wear parts and many more fields of application. The main drawback of TiB2 is its brittle nature, which has limited its range of applications. Diamond-like Carbon (DLC) has been used in industrial applications, mainly for wear resistant parts. However, the application of DLC films has been limited by the level of internal stress accumulated during deposition. This thesis investigates the deposition of TiB2/DLC multilayer wear resistant coatings to overcome these limitations. The thesis focuses on the tribological effects caused by different deposition techniques on TiB2 ceramic used by the coatings industry today, in order to overcome the brittle nature of TiB2 and the lack of adhesion of DLC films. The multilayer coatings consisted of 25 bi-layers of TiB2/DLC. These TiB2/DLC coatings were fabricated, maintaining a constant composition wavelength (sum of two layers Î» =200 nm) for an array of ceramic fractions ranging from 25% to 95% by volume using as substrates, tool steel AISI 1095 and powder metallurgy aluminium alloys, type 2618. The effect of the DLC content on the structure and performance (hardness, adhesion and wear) of the films was investigated. The bi-layer thickness influences the failure patterns observed in the scratch testing. These observations have been used to optimise the multilayered coating structure. Multilayer coatings have been manufactured to increase surface hardness and wear resistance as applied to a commercial powder metallurgy Al alloys (Al 2618) used in the automotive industry. Optimum coatings have found hardness values of 27.8 GPa, with a critical load of 20 N and a friction coefficient of 0.47. As a result of wear tests the multilayer with 10% of DLC was found to be best compromise between high hardness (23.8 GPa), good adhesion (critical load higher than 20 N), low friction and low wear rate.

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Manhabosco, Taíse Matte. « Tribocorrosão da liga Ti6A14V, liga nitretada, Ti6A14V revestida por filmes Diamond-Like Carbon (DLC) e obtenção eletroquímica de filmes DLC ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2009. http://hdl.handle.net/10183/16202.

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Na presente tese realizou-se um estudo a respeito da tribocorrosão, isto é, atuação simultânea dos mecanismos de desgaste e corrosão, da liga Ti6Al4V, da mesma liga nitretada e dela recoberta por filmes DLC obtidos por PACVD em meio fisiológico simulado, considerando que ligas de titânio são amplamente empregadas em próteses sujeitas a esforços e os filmes a base de carbono apresentam grande potencial como biomaterial. Paralelamente foi estudada a obtenção de filmes DLC sobre titânio através de uma técnica pouco usual para aquisição destes revestimentos, a eletrodeposição. As amostras nitretadas foram caracterizadas ao MEV, por difração de raios X e microdureza. Os filmes produzidos por PACVD foram caracterizados ao MEV, espectroscopia Raman e a dureza, através de nanoidentação. Para os diferentes materiais, ensaios eletroquímicos, em solução fisiológica simulada, foram realizados a fim de verificar a resistência à corrosão e ensaios de desgaste a seco, para avaliar o comportamento tribológico.O comportamento frente à tribocorrosão, onde os mecanismos de desgaste e de corrosão atuaram simultaneamente, foram realizados para a liga, liga nitretada e filmes DLC depositados por PACVC. A liga Ti6Al4V mostrou-se bastante resistente à corrosão, apesar do pobre comportamento tribológico. Ensaios de tribocorrosão confirmaram a boa resistência à corrosão da liga, mesmo com os mecanismos de desgaste e corrosão atuando simultaneamente. A camada de nitretos, obtida do processo de nitretação, apresentou melhora no comportamento tribológico, frente à corrosão e tribocorrosão. Filmes DLC apresentaram excelente resistência ao desgaste e à corrosão quando ensaios foram realizados separadamente. Ensaios de tribocorrosão mostraram a falha prematura do filme quando da atuação simultânea dos mecanismos. O estudo paralelo a respeito da eletrodeposição confirmou a possibilidade de obtenção de filmes DLC através desta técnica, a temperatura ambiente. Os filmes foram avaliados por espectroscopia Raman e testados quanto à resistência à corrosão e ao desgaste. A dureza dos filmes foi avaliada por nanoidentação e a morfologia, verificada ao MEV e AFM. Filmes obtidos a partir de acetonitrila apresentaram uma melhora na resistência à corrosão comparado ao titânio puro, enquanto que os filmes obtidos de DMF comportaram-se similarmente ao titânio, possivelmente pela presença de trincas nanométricas. Relativo à resistência ao desgaste, os filmes obtidos de DMF, mostraram-se mais eficazes.
In the present work it was performed a study about tribocorrosion performance of Ti6Al4V bare alloy and the same alloy Ti6Al4V nitrided or even recovered by DLC films in simulated physiologic environment considering the extensive application of this alloy in loaded implants and the possibility to use DLC films as a biomaterial. At the same time, it was studied the electrodepositon of DLC films onto titanium. Nitride samples were characterized by SEM (scanning electron microscopy), X ray diffraction and microhardness. The DLC films obtained by PACVC technique were characterized by SEM, Raman spectroscopy and nanoidentation. Corrosion experiments were conducted in simulated physiologic environment. The tribologic behavior was evaluated by dry wear tests. Tribocorrosion behavior, with corrosion and wear mechanisms acting simultaneously, was evaluated for the bare alloy, nitrided alloy and DLC films obtained by PACVD technique. The alloy is quite resistant to corrosion despite its poor tribological behavior. Tribocorrosion tests confirmed the good resistance to corrosion even when the degradation mechanisms of wear and corrosion act simultaneously. The nitride compound layer improved the tribological, corrosion and tribocorrosion behavior. DLC films presented high performance to either corrosion or wear mechanisms, however a catastrophic failure of the coating was observed in tribocorrosion tests. A parallel study confirmed the possibility of obtaining DLC films by a electrodeposition technique at room temperature. Raman measurements, corrosion and wear tests were performed. The hardness of the films was evaluated by nanoidentation. Films obtained from acetonitrile present a better corrosion resistance with respect to pure titanium. Films obtained from DMF presented a similar corrosion behavior as presented by titanium probably due the presence of some detected nanocracks. The films obtained from DMF presented a better tribological behavior.

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Renman, Viktor. « Tribological testing of DLC coatings for automotive applications ». Thesis, Uppsala universitet, Tillämpad materialvetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-177355.

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In this work, the friction and wear behavior of three DLC coatings was evaluated in various conventional and alternative fuels as well as in commercially available formulated engine oils and additive-free synthetic oil. The first DLC has a thin top-coating of hydrogenated amorphous carbon (a-C:H), the second consists of Si-doped DLC (a-C:H:Si) and the third is a W-doped multilayered structure of a-C:H and a-C:H:W. The tribological tests were performed using a ball-on-flat reciprocating rig at low contact pressures. Methods such as white light interferometry (VSI), scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS), Raman spectroscopy, transmission electron spectroscopy (TEM) and electron spectroscopy for chemical analysis (ESCA/XPS) were used for analyzing and characterizing the coatings and counter surfaces in an effort to gain an understanding of the tribological mechanisms involved.

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Crawford, Richard I. « Novel routes to DLC and related wear coatings ». Thesis, University of Ulster, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284837.

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Young, Sheng-Yu. « DLC thin film assisted zinc oxide nanowires growth ». College Park, Md. : University of Maryland, 2008. http://hdl.handle.net/1903/8613.

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Thesis (M.S.) -- University of Maryland, College Park, 2008.
Thesis research directed by: Dept. of Materials Science and Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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Wu, Jianhui. « Tribological behavior of WC-DLC-WS2 (WCS) nanocomposite coatings ». Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1094675462.

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Thesis (Ph. D.)--Ohio State University, 2004.
Title from first page of PDF file. Document formatted into pages; contains xix, 188 p.; also includes graphics. Includes bibliographical references (p. 179-188).

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Salvaro, Diego Berti. « Avaliação tribológica de DLC em regime de lubrificação mista ». reponame:Repositório Institucional da UFSC, 2015. https://repositorio.ufsc.br/xmlui/handle/123456789/159648.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Ciência e Engenharia de Materiais, Florianópolis, 2015.
Made available in DSpace on 2016-03-01T04:04:20Z (GMT). No. of bitstreams: 1 337499.pdf: 3616668 bytes, checksum: 5d5aef3c5b1c288568c3f8c612d16b27 (MD5) Previous issue date: 2015
A lubrificação fluida é um ramo da tribologia bastante desenvolvido devido às inúmeras aplicações nos mais diferentes segmentos industriais. O regime de lubrificação limite é responsável por significativa parcela de perdas por atrito e desgaste em sistemas lubrificados. Por esse motivo, os óleos lubrificantes possuem aditivos em suas formulações para que os mesmos reajam com as superfícies em contato e movimento relativo para gerar tribofilmes antidesgaste na região do contato. Os aditivos possuem em sua composição química elementos como fósforo e enxofre que em grandes concentrações podem trazer danos à saúde humana e ao meio ambiente. Consequentemente, legislações cada vez mais severas pressionam para redução, ou até mesmo eliminação desses aditivos nos lubrificantes. Os DLC são revestimentos a base de carbono amorfo que possuem além de alta dureza e estabilidade eletroquímica, propriedades autolubrificantes. Portanto, os DLC possuem grande potencial para redução dos aditivos nos óleos, principalmente em regimes de lubrificação limite. Diversos estudos já foram conduzidos nesse sentido, contudo, a grande maioria deles utiliza óleos e aditivos da indústria automotiva de elevada viscosidade. É exatamente nesse ponto que o presente trabalho exerce grande avanço, pois avaliou o desempenho tribológico do DLC (a-C:H) em um cenário típico da indústria de compressores herméticos para refrigeração, ou seja, com lubrificante de baixa viscosidade (4,2mm²/s a 40°C). Para atingir os objetivos foram realizados testes com a configuração cilindro-plano (contato em linha), onde um cilindro desliza (movimento alternativo) sem rolar sobre uma superfície plana durante tempo e força normal pré-determinados. Os testes foram realizados a seco e repetidos com a presença do óleo. Foram analisadas as marcas de desgaste via microscopia óptica e eletrônica, interferometria óptica de luz branca, espectroscopia Raman e espectroscopia de energia dispersiva. Os resultados mostraram que o comportamento tribológico dos pares testados a seco são governados por tribocamadas, que por sua vez são formadas por partículas de desgaste oxidadas sujeitas a ação do contato. Além disso, foi encontrado carbono na forma de grafite nessas tribocamadas. A presença do óleo reduz o coeficiente de atrito dos pares testados e o aditivo BTP reage com as superfícies metálicas para formar tribocamadas antidesgaste. Mecanismos dúcteis atuam no desgaste do ferro fundido enquanto que no DLC ocorre degradação por mecanismo frágil. A sinergia entre tribocamadas provenientes da reação do aditivo com superfícies metálicas e a possível grafitização do DLC governam o desempenho tribológico dos pares envolvendo DLC e ferro fundido cinzento.

Abstract : Liquid lubrication is a well-established technological branch due to several applications in different industrial segments. Boundary regime lubrication is responsible for a significant amount of frictional losses and wear in lubricated systems. For this reason, lubricating oils are usually formulated with different types of additives in order to form protective antiwear tribofilms on the real contact regions. Additives are composed of elements like phosphorus and sulfur that might be hazardous to human health and the environment when added in high concentrations. Therefore, severe regulations demand the reduction or even removal of such additives from lubricants. Diamond-like carbons (DLC) are a family of coatings containing high amounts of amorphous carbon that possess high hardness, chemical stability and self-lubricating properties. For this reason, DLCs have great potential in reducing the usage of additives in oils, especially in boundary lubrication regimes. Many studies have been conducted in this matter. However, these are mainly focused on automotive industry additives and oils with high viscosity. The main contribution of the present study is exactly on this point, since the hydrogenated DLC (a-C:H) in a typical hermetic compressors for refrigeration scenario was evaluated, with low viscosity oils (~4.2 mm²/s). The pair chosen was a cylinder vs plane, where the cylinder slides in a reciprocating movement without rolling on a plane surface during a constant time and normal load pre-determined. Dry and lubricated tests were conducted with the same configurations. Wear scars were analyzed using optical and electronic microscopy, white light interferometry, Raman spectroscopy and EDS. The results show that the tribological behavior of tested pairs under dry conditions are governed by tribolayers, generated by oxidized debris submitted to contact conditions. Furthermore, graphitic carbon was found in these tribolayers. Under lubricated conditions, the coefficient of friction (COF) is reduced and the BTP additive reacts with metallic surfaces in order to form antiwear tribolayers. Ductile mechanisms act in wear of cast iron while DLC wear occurs due fragile mechanisms. The synergy between tribolayers originated from reactions of the additive and metallic surfaces and DLC graphitization during friction determine the tribological behavior of pairs involving DLC and gray cast iron.

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Ko, Chi-fat, et 高自發. « Molecular regulations of deleted in liver cancer (DLC) protein family ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B41896889.

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Ko, Chi-fat. « Molecular regulations of deleted in liver cancer (DLC) protein family ». Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B41896889.

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Corcuera, Valerie Cecile. « Filmes de DLC com nanocristais de diamante para aplicações espaciais ». Instituto Nacional de Pesquisas Espaciais (INPE), 2016. http://urlib.net/sid.inpe.br/mtc-m21b/2016/06.23.18.37.

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Devido à tendência de aglomeração o desenvolvimento na funcionalização e posterior dispersão do pó de nanodiamante (ND) produzido por detonação pode se tornar um desafio. O pó do ND foi purificado por meio de tratamento térmico e dois tipos de funcionalizações foram alcançadas ND-COOH e ND-H. A purificação e as funcionalizações foram alcançadas com sucesso e foram verificadas por TGA e FT-IR. A análise de AFM mostrou que o tratamento térmico de oxidação que fornece a funcionalização do ND-COOH reduz os aglomerados em cerca de 74\% do tamanho original. O tamanho médio dos aglomerados do ND-COOH conforme medido por dispersão dinâmica de luz foi substancialmente reduzido em 95\% do tamanho original após a funcionalização e desagregação mecânica do pó em meio líquido. A estabilidade da dispersão do ND em solvente polar tetrahidrofurano aumentou consideravelmente apresentando um potencial zeta de -31 mV. Esta tese contemplou o desenvolvimento de uma nova metodologia para a dispersão dos aglomerados de nanodiamante (ND) em meio líquido. Filmes de carbono tipo diamante (DLC - Diamond-Like Carbon) contendo nano partículas de diamante foram depositados sobre amostras planas de liga de titânio Ti6Al4V pela técnica de DC pulsada PECVD (Plasma Enhanced Chemical Vapor Deposition). Soluções precursoras para deposição de filme de DLC foram preparadas. Filmes de DLC e DLC-ND foram produzidos a partir de diferentes solventes de natureza polar e apolar e as suas propriedades foram avaliadas. Análises comparativas de perfilometria, coeficiente de atrito, espectroscopia de espalhamento Raman foram abordadas. As análises de MEV e AFM revelaram a presença do ND no filme.
Due to agglomeration tendency the development of functionalization and subsequent dispersion of detonation nanodiamond (ND) powder can become a challenge. ND powder was purified by heat treatment and two types of functionalizations were achieved ND-H and ND-COOH. Purification and functionalizations were successfully achieved and were verified by TGA and FT-IR. AFM analysis showed that the thermal oxidation treatment which provides ND-COOH functionalization reduces the agglomerates in about 74\% of the original size. The average size of ND-COOH agglomerates as measured by dynamic light scattering has been significantly reduced by 95\% of its original size after functionalization and mechanical shearing of the powder in a liquid medium. The stability of ND dispersion in polar solvent tetrahydrofuran increased considerably having a zeta potential of -31 mV. Development of a new method for the dispersion of agglomerated nano diamond (ND) in a liquid medium was included in this thesis. Diamond-Like Carbon (DLC) films with nano diamand particles were deposited on flat samples of titanium alloy Ti6Al4V by pulsed DC Plasma Enhanced Chemical Vapor Deposition (PECVD). Precursor solutions for DLC films deposition were presented. DLC and DLC-ND films were produced from different polar and nonpolar solvents and their properties were evaluated. Comparative analyzes profilometry, friction coefficient, Raman spectroscopy have been addressed. SEM and AFM analysis revealed the presence of ND in the film.

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Lehmkühl, Niklas, et Raoul Man. « How Do Different DLC Delivery Methods Impact Appeal and Effectiveness ». Thesis, Uppsala universitet, Institutionen för speldesign, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-388641.

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Downloadable content (DLC) distribution models employ various methods to keep consumers interested. Some methods encourage consumers to purchase and engage with a DLC model and some methods discourage consumers from engaging with the model. This study seeks to determine which models keep consumers interested and which discourage consumers from purchasing DLC. We do this by reaching out to multiplayer communities of four different games that are affected by different models and have them fill out a survey regarding their purchasing behaviour. After analysing the results, we concluded that models that require players to own the same DLC in order to play together or that utilize watermarks for DLC that are not owned, are less effective at incentivizing players to purchase when compared to models that either allow players to share DLC, or acquire it through in-game means.
Distributionsmodeller för nedladdningsbart innehåll använder olika metoder för att hålla konsumenterna intresserade. Vissa metoder uppmuntrar konsumenter att köpa och engagera sig i en DLC-modell och vissa metoder avskräcker konsumenterna från att engagera sig med modellen. Denna studie syftar till att bestämma vilka modeller som håller konsumenterna intresserade och som avskräcker konsumenterna från att köpa DLC. Vi gör det genom att nå ut till multiplayer-grupper i fyra olika spel som påverkas av olika modeller och få dem att fylla i en undersökning om deras inköpssätt. Efter att ha analyserat resultaten drog vi slutsatsen att modeller som kräver att spelare äger samma DLC för att kunna spela tillsammans eller använda vattenstämplar för DLC som inte ägs, är mindre effektiva för att stimulera spelare att köpa jämfört med modeller som antingen tillåter spelare att dela DLC, eller skaffa det via in-game-medel.

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Yang, Liuquan. « DLC/friction reduction additives interactions in the boundary lubrication regime ». Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/10121/.

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Friction has enormous effect on energy consumption and wear limits the life time of many mechanical devices with relative motion components. The challenges in the automotive industry have been driven by fuel economy as well as stringent emission legislation for environmental sustainability. Improvements of coating deposition technology enable the mass production of high quality Diamond-Like Carbon (DLC) coatings at an industrial scale and also increase their use in lubricated contacts. However, the understanding of the interactions of different lubricant additives with this material is not yet fully developed. This study focused on several fundamental aspects of the tungsten-doped DLC coating (denoted as WDLC) behaviour under boundary lubrication conditions with model lubricants. Zinc dialkyldithiophosphate (ZDDP), glycerol monooleate (GMO) and molybdenum diakyldithiocarbamate (MoDTC) were used in these model lubricants. The primary test contact was semi-coated, i.e., WDLC vs. cast iron (CI). As references, steel/CI, non-doped DLC coating (NDLC)/CI and fully coated WDLC/WDLC interfaces were also studied. As the primary focus, WDLC/CI interface was tested not only at 100 °C, but also a wider service temperature from 30 °C to 150 °C. For the other references, tests were only carried out at 100 °C. The tribological tests were carried out by Cameron Plint TE77 reciprocating tribometer. Test simulation was based on the liner motion part of the camshaft/follower system in an internal combustion engine (ICE). This study demonstrated the characterization of WDLC coating lubrication by Raman spectroscopy. The effect of lubricant additives on the coating structure change was discussed in terms of carbon structure and the tungsten dopant. Electron Energy Loss Spectroscopy (EELS) and Raman spectroscopy characterization for the upper carbon layers indicated that the WDLC coating interacted chemically with selected lubricant additives. The testing temperature was proved to be critical in WDLC lubrication. The study also clarified the role of doping tungsten and its unique role in changing the tribological behaviours of DLC lubrication with references to NDLC coating tests. The fully coated WDLC/WDLC tests clarified further the tribofilm formation dependence of ferrous surface for ZDDP and MoDTC additives. The formation of tribofilm of GMO on WDLC coated surface had less dependence than on ferrous materials. Different models of lubrication in semi-coated WDLC/CI interface were proposed individually in the concluding chapters and the role of tungsten carbide in changing the tribochemical interaction of GMO+ZDDP lubricant compared with NDLC/CI interface was further discussed. Overall, this study provided fundamental aspects for better understanding of interactions between current ferrous based additives (with a further reduced treat rate) and WDLC coating in a semi-coated tribological system. The methodology and results should contribute both the fundamental science and engineering practices which the engineering science community should be benefited from.

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binti, Nik Roseley Nik Roselina. « Fabrication and characterisation of DLC-graphene nanocomposite coatings for tribological application ». Thesis, University of Leeds, 2019. http://etheses.whiterose.ac.uk/22712/.

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This work presents the development and characterisation of single and multilayer Diamond-Like Carbon (DLC)-graphene nanoplatelet (GNP) nanocomposite coatings. This study opens up a new challenge in the fabrication of carbon composites using DLC and GNP with enhanced mechanical and tribological properties. The purpose of the composite is to exploit the advantages of the excellent mechanical and tribological properties of graphene that have been reported by many works. The objectives of this thesis are to develop a method to fabricate DLC and GNP nanocomposite coatings, to prepare the nanocomposite coatings and to investigate their physical, mechanical and tribological properties. The fabrication of DLC-GNP nanocomposite coatings was carried out using the combination of spin coating of GNP and DLC deposition using PECVD. The two types of DLC-GNP that have been prepared are single-layer and multilayer. The surface morphology and microstructure of DLC-GNP was characterised using optical microscopy and Scanning Electron Microscopy (SEM). Focused Ion Beam (FIB) SEM was used to observe the layers in the composite and measure the thickness of the multilayer DLC-GNP nanocomposite coating. The coating comprises the interlayer, spin-coated GNP and DLC film. This study shows that an optimised post-treatment is required to substantially improve the adhesion strength of spin-coated GNP and thus that of the whole nanocomposite coating. It was observed that columnar structure was generated in-situ during a wear tests on coatings post-treated for more than 180 minutes. The results were unintentionally found after three hours of sliding test. The columnar structure contributed to the significant reduction of the coefficient of friction (CoF) to 0.06, and the wear rate compared to other samples. According to Raman spectroscopy analysis, both single and multilayer DLC- GNP nanocomposite coatings have typical spectra similar to that of pure DLC. However, DLC-GNP has a broad range of ID/IG ratio values compared to pure DLC due to the dispersion of spin-coated GNP. The observation though cross-section FIB also proved that DLC film covered the spin-coated GNP by creating a bonding layer during DLC film deposition. The multilayer DLC-GNP demonstrated major improvements in adhesion strength of almost doubling the value obtained by single-layer DLC-GNP. The wear resistance also increased remarkably which can be related to the enhancement of adhesion strength. It is proposed that the GNP in the composite is released during the running-in period and acted as a slider between the counterpart and coating.

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Peng, Xilin. « Synthesis and adhesion of diamond and diamond-like carbon (DLC) films ». Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624958.

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Hofmann, Dieter. « Si-DLC coatings optimized for low wear and low friction applications ». Thesis, Sheffield Hallam University, 2014. http://shura.shu.ac.uk/19805/.

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Diamond-like carbon (DLC) has excellent properties for the use as tribological coating such as high hardness, high wear resistance and a low friction coefficient. Nanolayer systems of hydrogenated diamond-like carbon (a-C:H) and silicon doped hydrogenated diamond-like carbon (Si-DLC or a-C:H:Si) have been studied. The objectives of this work are to develop layer combinations which allow combining low abrasive wear, low friction properties, and improved temperature stability for the coatings. A literature survey on sputtering, plasma enhanced chemical vapor deposition (PECVD) and carbon based materials with a focus on a-C:H and Si-DLC coatings is given. This survey includes a brief overview of the 60 years history of DLC coating. In the second part of the thesis, the experimental set up for the layer preparation by a magnetron based deposition method and a basic description of the process are presented. Using sputtering from a solid SiC target as a source of the Si for the Si-DLC instead of the commonly used PECVD process with Si-containing precursors Si-DLC/a-C:H nanolayers were deposited at high deposition rates. For the coatings, the influence of the acetylene gas flow, the bias voltage, and the hydrogen and silicon concentration are discussed. Undoped a-C:H coatings with high indentation hardness above 40 GPa and very low abrasive wear rates of 0.6 x 10[-15] m[3]/(Nm) and low hydrogen content of about 11 at.% were deposited. Si-DLC/a-C:H nanolayer coatings with high hardness of 20 to 30 GPa and a high temperature stability up to 500 °C were prepared. For these nanolayer films low friction coefficients of 0.06 to 0.11 and high abrasive wear rates of > 2.5 x 10[-15] m3/(Nm) were achieved at high silicon contents above 15 at.%. On the other hand nanolayer coatings with low silicon contents of less than 10 at.% showed low wear rates below 1.7 x 10[-15] m3/(Nm) combined with higher friction coefficients of 0.12 to 0.15. In order to combine the low abrasive wear rate and the low friction coefficient at first a Si-DLC/a-C:H layer with low Si-concentration followed by a second layer with high Si-concentration was deposited. Due to the low surface free energy of Si-DLC coatings of 30 to 35 mN/m the wetting behavior for some lubricants may deteriorate. In this case a further optimization of the nanolayer system is required.

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Huang, Liyie. « Caractérisation et propriétés nanomécaniques des différents films DLC (diamond-like carbon) ». Troyes, 2002. http://www.theses.fr/2002TROY0001.

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Cette étude porte sur les films DLC (diamond-like carbon). La charge critique lors d'un test de rayure augmente avec l'épaisseur inter-couche. Pour une épaisseur inter-couche donnée, la charge critique varie linéairement avec la dureté du film et son épaisseur. Le bas coefficient de frottement viendrait de la combinaison de la dureté élevée, de la faible rugosité et de la faible proportion de sp3. Dans le cas du fretting, le coefficient de frottement et l'humidité relative varient inversement. La proportion de sp3 augmente avec l'introduction de Si, ce qui fait monter la dureté, diminuer les frotements et augmenter la stabilité thermique de films a-SIC:H. L'augmentation de la fraction de sp3 dans les films a-C déposés par arc pulsé sous vide correspond bien à celles de la dureté et de la charge critique de rayure. Le fim a-C déposé par laser pulsé possède d'importantes contraintes internes. Un mécanisme de formation faisant appel à la théorie du flambement des coques est proposé. Le test de rayure des films DLC est divisé en 3 étapes : recouvrement élastique total, déformation plastique du film, délamination et écaillage du film. Cette résistance a d'abord été mesurée pour des films DLC sur substrat de Si. Il s'avère, à l'analyse élasto-plastique de la déformation au cours de la nanorayure, que la charge critique d'un film DLC sur Ti-6AI-4V est atteinte lorsque les déformations élastique et plastique sont comparables. L'analyse des expériences et de la morphologie de rayure nous permetttent de déduire que les mécanismes de rupture des films DLC sur Si et Ti-6AI-4V sont différents. Le relief des contraintes induits après rayure par le flambement a été modélisé afin de déterminer la charge de flambement critique. La rupture des films DLC sur Si, lors d'un test de rayure, a été modélisée en utilisant une analyse de flambement circulaire et ceci a été utilisé pour calculer énergie de rupture interfaciale et la résistance à la rupture.

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Maerten, Thibault. « Study of corrosion resistance of steel coated with DLC thin films ». Thesis, Limoges, 2019. http://www.theses.fr/2019LIMO0105.

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Les couches minces DLC (Diamond Like Carbon) ont fait l’objet depuis près de 25 ans de recherches principalement axées sur leurs propriétés tribologiques et leur optimisation. Ces couches minces sont maintenant matures (TRL 9) et reconnues pour leur très fort potentiel de réduction du frottement et de l’usure. Elles sont employées par de nombreuses industries : les DLC sont des solutions technologiques courantes pour réduire les frottements dans les moteurs de voitures de grande série (pièces de distribution, axe de piston...). De nombreuses études scientifiques ont aussi identifié la grande inertie chimique de ces couches à base de carbone et d’hydrogène dans des environnements liquides agressifs (acides ou basiques) et contenant des chlorures. Basé sur ces constatations, l’utilisation de matériaux à base de DLC, pour des applications tribologiques nécessitant aussi une bonne résistance à la corrosion des pièces revêtues, est envisagée. Dans la plupart des applications visées, les pièces sont faites d’aciers présentant de hautes propriétés mécaniques (ex. : 100Cr6 – acier à roulements) mais ayant souvent une résistance à la corrosion très faible.Dans un contexte industriel, l'évaluation de la protection contre la corrosion des films minces est menée, la plupart du temps, avec des tests de brouillard salin neutre. En laboratoire, elle est principalement effectuée à l'aide de techniques électrochimiques. Dans le cadre de cette thèse, les deux techniques ont été utilisées et adaptées pour une évaluation cohérente et répétable de la résistance à la corrosion d’aciers revêtus de couches minces à base de carbone.Une évaluation des couches minces DLC existantes d’Oerlikon Balzers sur acier 100Cr6 a été faite. Cette évaluation a été réalisée à l'aide d'essais en brouillard salin neutre et d’essais électrochimiques classique telles que des courbes de polarisation (avec mesure préalable du potentiel de circuit ouvert). La corrosion du substrat en acier revêtu s'est avérée être variable en fonction des solutions de revêtement DLC testées. Dans tous les cas, une faible résistance à la corrosion des éprouvettes revêtues a été détectée. L’origine de la corrosion d’acier revêtu de couche minces DLC a été étudiée. Les défauts dus aux procédés de dépôt des couches minces DLC se sont révélés être les principaux responsables de la mauvaise tenue à la corrosion des substrats revêtus. Pour étudier ces défauts, une nouvelle configuration électrochimique a été développée. Elle combine l’utilisation de séquence de polarisation avec des observations in situ de la surface. Cette méthode a permis le suivi des phénomènes de corrosion au niveau d’un unique défaut de taille micrométrique. Des défauts artificiels, de tailles micrométriques, ont été réalisés dans un revêtement DLC à l'aide d’une sonde ionique focalisée, plus connue sous le sigle anglais FIB (Focused ion beam) afin d’étudier les mécanismes de corrosion ainsi que la taille minimale des défauts susceptible de conduire à la dégradation par corrosion du substrat. Enfin, sur la base des défauts précédents et de leur étude, de nouvelles solutions de revêtements innovantes ont été développées et évaluées. Ces solutions sont divisées en trois parties basées sur des concepts de dépôts recensés par la littérature : une approche multicouches du dépôts, une approche par couplage galvanique favorable et pour finir une approche par ajout d’une couche barrière à la corrosion
Since almost 20 years, diamond-like carbon (DLC) thin films have been selected for tribological solutions mainly because of their excellent properties such as low coefficient of friction (five time less than bare steel in dry condition), high hardness (from 20 to 35 GPa for hydrogenated ones) and excellent wear properties (high abrasive wear resistance, preventing adhesive wear mechanisms). Most of the time, it has also been reported that DLC thin films have good intrinsic corrosion properties as they are chemically inert in sodium chloride solutions either in acid or basic environment. This has led to envision and evaluate the use of DLC thin films in tribological applications that also require complementary corrosion protection performances on coated parts (for instance: in aeronautic, in food industry for mechanical devices, in automotive for non-cosmetic part of structures). Typically, these coatings are deposited on steel alloys presenting high mechanical properties, such as tool steel or bearing ring steel that demonstrate poor or limited corrosion resistance.In an industrial context, the evaluation of corrosion protection of DLC thin films is presented, most of the time, with neutral salt spray tests or immersion tests, whereas at laboratory the evaluation would be mainly done using electrochemical techniques. In this work both techniques were used and also refined to specially fit the evaluation of such material. First, an evaluation of existing DLC based thin films from Oerlikon Balzers on mechanical steel were done as benchmark reference. This evaluation was conducted with NSS test and classic polarization experiments (open circuit voltage and linear sweep voltammetry). Corrosion of coated steel substrate was found to be variable depending on DLC coating solutions tested but, in all cases, a poor corrosion resistance of coated specimens was detected. Then origin of the poor corrosion protection aspect of DLC coating on steel substrate were studied. Defects coming from the deposition processes in coatings was found to be the main issues of poor corrosion results. To study such defects a new electrochemical setup was developed. It combines polarization experiments with in situ observations of a single defect at the surface. Artificial defects, with micrometric sizes, were milled in DLC coating using SEM-FIB to study the corrosion mechanisms as well as the minimum size of defects susceptible to lead to corrosion degradation. And finally based on the previous defects study, new and innovative coatings solutions were developed and evaluated. These solutions are divided in three parts based on coatings concepts found in literature: a multilayer approach, a galvanic coupling approach and a sealing layer approach

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Rizzo, Vinícius Zacarias. « Estudo das propriedades ópticas e eletro-ópticas de filmes de carbono amorfo tipo diamante - DLC ». Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/3/3140/tde-10012011-143459/.

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Neste trabalho foram estudadas as características elétricas e ópticas de filmes de carbono tipo diamante (DLC Diamond-Like Carbon) depositados em um sistema de sputtering RF magnetron reativo em substratos de silício e vidro. Foram depositadas amostras em condições de processo distintas em cada tipo de substrato, sendo duas condições de pressão (5 mTorr e 10 mTorr) e para cada uma, quatro condições de potência de RF (100 W, 150 W, 200 W e 250 W). Os filmes depositados foram submetidos às seguintes técnicas de caracterização: perfilometria, para obtenção da espessura dos filmes e com isso a taxa de deposição; elipsometria, para obtenção do índice de refração; obtenção de curvas I-V, para obtenção da resistividade elétrica e cálculo do ganho de foto corrente, e da curva C-V de alta frequência, para cálculo da constante dielétrica dos filmes; transmitância óptica, para o cálculo do gap óptico através do método de Tauc; fotoluminescência, para determinar a emissão característica deste gap e espectroscopia de infravermelho por transformada de Fourier (FTIR), para se observar os tipos de ligações presentes no filme e calcular a relação entre hibridizações sp3 e sp2 entre átomos de carbono e hidrogênio no filme. As variações de algumas características dos filmes de DLC com os parâmetros de processo são apresentadas e comparadas. De acordo com as características dos filmes obtidos neste trabalho, com a variação dos parâmetros de processo, é possível sua aplicação como dielétrico de campo, por apresentarem baixa constante dielétrica, sendo o valor mais baixo obtido igual a 3,4; como material dielétrico de porta considerando os filmes com alta constante dielétrica, chegando a 6,7; como material para cobertura, devido à alta uniformidade (até 95%); e, o que foi mais explorado neste trabalho, para aplicações como sensores foto sensíveis, sendo que o maior ganho de foto corrente obtido foi 67 vezes. A possibilidade de produção de filmes de DLC com diferentes propriedades através da variação das condições de processo mostra sua versatilidade para uso em diferentes aplicações.
In this work it was studied electrical and optical characteristics of diamond-like carbon (DLC) films deposited in a reactive RF magnetron sputtering system on silicon and glass substrates. Samples were deposited at different process conditions in each type of substrate at two pressure conditions (5 mTorr and 10 mTorr) and four conditions of RF power (100 W, 150 W, 200 W and 250 W). The DLC films were characterized by the following techniques: high step meter analysis, to obtain the thickness of the films and thus the deposition rate; Ellipsometry to obtain the refractive index; electrical characterization by the I-V curve, to obtain the resistivity and calculate the photo current gain, and high-frequency C-V curve, to calculate the dielectric constant of the films; optical transmittance, to calculate the optical gap by the Tauc method; photoluminescence analysis, to determine the characteristic emission of this gap; Fourier transform infrared spectroscopy (FTIR), to observe the different carbon-hydrogen bonds and calculate its sp3/sp2 hybridizations ratio. The way some characteristics of DLC films vary with the process parameters are presented and compared in this work. According to the characteristics of the DLC films obtained in this work, with the variation of the process parameters it is possible their application as low k dielectric insulators, because of its low dielectric constant, being the lowest obtained value 3.4; as dielectric gate material, reaching 6.7 in the films deposited in this work, as coating material due to its high uniformity (95%), and which was further explored in this work, for applications like photo-sensitive sensors, since it was obtained samples with photo current gain up to 65. The possibility of producing DLC films with different properties by varying process parameters shows its versatility for using in different applications.

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Silvério, Márcio. « Comportamento tribológico de revestimento multifuncional CrN-DLC em atmosferas de gases refrigerantes ». reponame:Repositório Institucional da UFSC, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/94062.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Ciência e Engenharia de Materiais, Florianópolis, 2010
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Um dos maiores motivadores de pesquisas mundiais, a redução do consumo de energia elétrica, é também motivo de inúmeras discussões relacionadas ao aquecimento global. No Brasil, no ano de 2008, 24% do consumo de energia elétrica foi demandado apenas no setor residencial, onde os equipamentos eletroeletrônicos são fortes responsáveis pelo consumo. Estima-se que, atualmente, somente a indústria de refrigeração seja responsável pelo consumo de 17% de toda a energia elétrica consumida nos Estados Unidos. Ultimamente um número elevado de pesquisas vêm sendo desenvolvidas, objetivando a redução do atrito e do desgaste. Estas pesquisas evoluíram desde sistemas lubrificados, passando pelo uso de aditivos e, finalmente, a utilização de revestimentos de lubrificantes sólidos. Muitas soluções encontradas esbarram em dificuldades de adequação de projetos e condições de aplicação severas. O uso de gases refrigerantes é um deles, uma vez que interfere diretamente na viscosidade de óleos lubrificantes e interfaces de contato de mancais. No presente estudo foi investigada a influencia de gases refrigerantes HFC134a e HC600a no comportamento tribológico de um revestimentos multifuncional de CrN-DLC. O objetivo deste estudo foi identificar tanto as perdas por atrito, quanto por desgaste deste revestimento em função das interações com os gases refrigerantes utilizados. Para entender tais propriedades foram propostos dois tipos de ensaios tribológicos: um para avaliar a durabilidade dos revestimentos em função de aplicação de cargas normais variáveis, e outro para determinação do coeficiente de atrito, bem como, da taxa de desgaste dos revestimentos nas duas atmosferas. Os corpos de prova e contracorpos foram caracterizados via espectroscopia Raman e EDS para identificar as modificações ocorridas nas interfaces de contato. Os resultados dos testes de durabilidade com gás refrigerante HFC134a apresentaram-se aproximadamente 40% superiores que os resultados dos testes com gás refrigerante HC600a. De modo similar, os valores de coeficiente de atrito também apresentaram valores maiores nos ensaios com gás refrigerante HFC134a. Entretanto, os resultados da taxa de desgaste do revestimento foram 50% menores nos testes com este gás refrigerante. Os contra corpos apresentaram uma taxa de desgaste muito mais elevada que nos corpos, atingindo valores acima de uma ordem de grandeza quando comparado aos valores da taxa de desgaste dos corpos. Através da caracterização química por espectroscopia Raman e EDS identificou-se a presença de compostos fluorados na tribocamada formada sobre a pista de desgaste do DLC, bem como, no contracorpo quando utilizado o gás refrigerante HFC134a. Entretanto, não foi detectada a transferência de DLC para as superfícies dos contracorpos. A presença de Flúor na tribocamada provavelmente está associada à degradação do gás refrigerante durante os ensaios tribológicos. Em contrapartida, nos ensaios com HC600a foi detectada a transferência de DLC para os contracorpos, conforme identificado nas análises via espectroscopia Raman. Todos os testes mostraram traços de oxigênio na tribocamada, os quais foram associados à presença de contaminantes adsorvidos nas amostras, bem como, à falta de hermeticidade da câmara de ensaio utilizada nos ensaios tribológicos.
One of the major drivers of global research, reducing energy consumption, is also a matter of considerable discussion related to global warming. In Brazil, in 2008, 24% of electricity consumption was consumed only in the residential sector, where electric-electronic devices are responsible for most part of this consumption. It is estimated that only the refrigeration industry is responsible for consuming 17% of all electricity consumed in the United States. Recently a great number of studies are being developed, aiming the friction and wear reducing. These studies evolving since lubricated systems, passing through the usage of additives in lubricant oils, and finally, arriving in the use of coatings of solid lubricants. Many solutions are hindered by difficulties of adaptation in projects and severe application conditions. The use of refrigerant gases is one of them, since it directly interferes with the viscosity of lubricant oils and contact interfaces of bearings. In the present study it was investigated the influence of the refrigerant gases HFC134a and HC600a on the tribological behavior of a multifunctional coatings of CrN-DLC. The aim of this study was to identify since the friction losses, as the wear of this coating due to interactions with the proposed refrigerant gases. To understand these properties have been proposed two types of tribological tests: one to evaluate the durability of the coating as a function of variable applied normal loads, and another to determine the coefficient of friction as well as the wear rate of coatings in both atmospheres. The specimens and counter bodies were characterized via Raman spectroscopy and EDS to identify the modifications on the contact interfaces. The durability tests results with refrigerant HFC134a showed durability of about 40% higher than tests with HC600a. Similarly, the coefficient of friction values were also higher in trials with HFC134a. However, the results of the wear rate of the coating were 50% lower in tests of this refrigerant. Counter body analysis showed a wear rate even higher, amounting to approximately one order of magnitude. The chemical characterization by Raman spectroscopy and EDS revealed the presence of fluorinated compounds in tribolayer formed on the wear track of DLC and counter body with refrigerant gas HFC134a. In these trials were not detected the DLC transference to the counter body surfaces. The presence of fluoride in tribolayer may be related to degradation of the refrigerant gas during the tribological tests. In contrast, in trials with HC600a were detected transferring of the DLC to the counter body, as presented in the analysis via Raman spectroscopy. All tests showed traces of oxygen in tribolayer, associated with contaminants adsorbed on the samples and the lack of hermeticity of the test chamber used in the tribological tests.

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Stavlid, Nils. « On the Formation of Low-Friction Tribofilms in Me-DLC – Steel Sliding Contacts ». Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7369.

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Ahmed, Mukhtar Hassan. « The effect of structure and composition of DLC on the adsorption of glycine ». Thesis, University of Ulster, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.497333.

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30

Blau, Anja [Verfasser], et Ludger [Akademischer Betreuer] Deters. « Ermittlung von Verschleiß bei kraftstoffgeschmierten Stahl-DLC-Gleitpaarungen / Anja Blau. Betreuer : Ludger Deters ». Magdeburg : Universitätsbibliothek, 2013. http://d-nb.info/1054420297/34.

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31

Loewen, Shauna. « Dlc-1 and Dlc-2 : studies of two RhoGAP genes in etoposide resistance and apoptosis ». 2008. http://hdl.handle.net/1993/21077.

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ABDOLLAH, Mohd Fadzli Bin. « Impact Wear Mechanisms of DLC Coating ». Thesis, 2011. http://hdl.handle.net/2237/16458.

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Wang, Shii Haw, et 王璽皓. « Tribology Potential of DLC Coated Milling Inserts ». Thesis, 1998. http://ndltd.ncl.edu.tw/handle/05491642114000790287.

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碩士
國立成功大學
機械工程學系
86
Tribology potential of diamond-likecarbon(DLC) coatings was discussedin this thesis. Before milling experiments, DLC coatings were coated ontungsten carbide-cobalt(WC) alloy milling inserts. The DLC coatings aremetal doped diamond-like carbon(Me- C:H). There were metals doped inDLC coatings, titanium and chromium. The workpiece used in experimentsis 7075 aluminum alloy.Experiments were carried out under dry andcoolant conditions on NC machining center. TiN, TiCN, CrN and CrCNcoatings were also compared with DLC coatings in experiments.The experiment results are shown as follow: Increase the thickness of DLCcoatings conduce to high residual stress and peel off the coating layers.Increasing the doping metal may meliorate this situation. Sp2 and sp3 carbonbonds in DLC coatings were identified by Raman test. On the other hand,the DLC coatings used in experiments contain tetrahedron structure. In the first step of milling test, we used the confirmation and analysesrecommended by Taguchi method to optimizea condition for milling. Themost significant factor among the four factors in this experiment(thicknessof DLC coating, milling speed, milling depth and feed rate)is the thicknessof DLC coatings, so we focus the parameters on coating conditions in the later.As a result, the best thickness of DLC coatingis 2.5μm.In the case of 3.5μm coatings, the coating layers were peeled off. For different dopingmetals, titanium series were better than chromium series in flank wear. Incoolant condition, the DLC coatings performed nice tribology potential.This result indicated that the DLC coatings used in this experiment arestable in humid environment. When milling S45C, the high feed ratecondition in milling test made the tool fractured, but the DLC coatings stillreduce the degree of fracture.

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Wu, Chin-Lung, et 巫金龍. « DLC Film Growth and MIS Devices Characterization ». Thesis, 2006. http://ndltd.ncl.edu.tw/handle/12016459966205978684.

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碩士
國立中山大學
電機工程學系研究所
94
Diamond-Like carbon (DLC) films has a lot of advantages, such as high hardness, high thermal conductivity, low expansion coefficient, low friction coefficient, high chemical stability, high impedance. These properties make the DLC films suitable for becoming an insulator in metal insulator semiconductor structure. In this study, DLC films were deposited by electro-deposition technique onto silicon (Si) substrates, in which a mixture of acetic acid and water is used as the electrolyte. The structure of the DLC films is characterized by Raman Spectroscopy. The thermal evaporation technique was used to deposit an aluminum films on the DLC/Si-substrates, to make it as the structure of metal-insulator semiconductor (MIS), and the electrical properties of the MIS were measured by semiconductor parameter analyzer. DLC films were deposited by varying the parameters of electro-deposition process included mainly as the concentration of solution, the spacing between electrode and silicon substrate, deposition temperature, and the applied voltages. The properties and film growth of DLC attributed to the effect of parameters were described in detail. Finally, an electro-deposition model is obtained to describe the growth mechanism of electro-deposition of DLC film.

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Frois, António Manuel Jacinto. « Funcionalização de Ligas Ortodônticas com Revestimentos DLC ». Master's thesis, 2018. http://hdl.handle.net/10316/86117.

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Trabalho de Projeto do Mestrado Integrado em Engenharia Biomédica apresentado à Faculdade de Ciências e Tecnologia
Biometals stand out in orthodontics due to the excellent combination of mechanical-chemical-physical properties. However, one of the most important considerations is their deterioration by intraoral corrosion, leading to metallic ions release with an inevitable harmful effect on human health and wellness. In fact, the cytotoxicity of Ni, Cr and Fe has been highlighted, and both Ni and its compounds are considered to be carcinogenic according to IARC. It is therefore imperative to develop and implement new strategies in order to minimize those effects without loss in biocompatibility. The present work is related to the Surface Engineering field, and the objective is the development of Diamond-Like Carbon coatings, by magnetron sputtering, as functional barriers to metal release from biomedical metallic alloy. The corrosion resistance of single (DLC) and 10 at.% W-doped (DLC:W) films with Cr interlayer for adhesion improvement was studied. The static immersion tests were performed in artificial saliva solution by selecting two pH values and two bathing times. The corrosion behaviour of fixed orthodontic treatment components was also analysed. The chemical and morphological characterization of the samples was performed by SEM/EDS and AFM, and the contact angles were also measured. The quantification of metallic ions released into the immersion solution baths was obtained by ICP-AES. The results were very satisfactory. It was shown that pitting corrosion, which was detected on austenitic stainless steel orthodontic components, could be avoided by using DLC-based coatings, especially in highly acidic environment. Moreover, the best corrosion behaviour was observed for the single DLC coatings, being the biocompatibility an additive factor. However, the DLC:W coatings did not fulfil the primary expectations, despite of the unchanged chemical composition and morphology characteristics after salivary tests in any aqueous conditions.
O recurso a componentes de base metálica na área ortodôntica é recorrente e importante, já que esta classe de materiais exibe um conjunto de propriedades adequadas àquela aplicação. Contudo, existe uma crescente preocupação quanto aos efeitos dos iões metálicos libertados para o corpo humano, resultantes da corrosão in vivo destes materiais. Destaca-se a citoxicidade do Ni, Cr e Fe, em que tanto o Ni como os seus compostos são considerados carcinogénicas para humanos, de acordo com a IARC. Assim, torna-se necessário desenvolver e implementar novas estratégias que minimizem estes efeitos sem perda de biocompatibilidade.O presente trabalho insere-se na área da Engenharia de Superfícies e incide no desenvolvimento, por pulverização catódica magnetrão, de filmes Diamond-Like Carbon como barreira à difusão de metais em ambiente oral. Estudaram-se filmes singulares (DLC) e aditivados com 10 %at. de W (DLC:W), melhorando a adesão ao substrato metálico pela deposição de uma intercamada de Cr. A resistência à corrosão foi avaliada em condições estáticas de imersão em saliva artificial a diferentes tempos e pHs. Foi ainda incluído neste trabalho o comportamento à corrosão de vários componentes constitutivos de um aparelho fixo ortodôntico.A caracterização passou pela avaliação da concentração de iões por ICP-AES e pela análise química e morfológica das superfícies, por SEM/EDS e AFM. A molhabilidade foi avaliada pela medição de ângulo de contato com a superfície. Os resultados obtidos foram bastante satisfatórios e mostraram que a corrosão por picada, observada nos aços inoxidáveis austeníticos das peças ortodônticas, pode ser evitada pelo tratamento das suas superfícies com revestimentos DLC, principalmente em meio aquoso muito ácido. Mais, os revestimentos singulares parecem ser uma solução eficaz na libertação de metais provenientes das bioligas com aumento da biocompatibilidade. Todavia, o comportamento dos filmes DLC:W não correspondeu às expectativas iniciais, apesar das invariâncias morfológicas e químicas registadas em todas as condições de imersão.

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Janez, Matej. « Electrical and Tribological Properties of DLC Coatings ». Master's thesis, 2015. http://hdl.handle.net/10316/39083.

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Dissertação de Mestrado em Engenharia de Materiais apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra.
DLC coatings have attracted interest of many researches due to their unique combination of properties. They are often used in various applications as protective coatings because of their excellent low friction and high wear resistance. However, little research has been done on the electric properties of DLC coatings and their possibilities in electric applications. The focus of this work was the analysis and comparison of electrical and tribological properties of selected commercial coatings in sliding electric contacts. In the thesis, the resistance, friction and wear behavior of four different coatings, which were selected based on their good electrical and tribological properties observed during preliminary testing, were evaluated and compared to steel at room temperature in dry reciprocating sliding mode and under different direct current conditions. Commercial DLC coatings selected for the analysis were Low Ti-DLC (5 at.%), High Ti-DLC (10 at. %), Low W-DLC (5 at.%) and High W-DLC (10 at.%). The tests were performed by simultaneously gathering friction and resistance data in the contact using a ball-on-disc tribometer and a voltage drop measuring setup. Optical microscopy and white light interferometry were used for the analysis of the wear scars. The results of the resistance measurements showed that all coatings conducted direct current. It was observed that higher doping element concentrations led to lower resistance of the contact. DLC – DLC contact also produced higher conductivity measurements compared to DLC – Steel contact. The conductivity of Steel – Steel contact was in a similar range as DLC – DLC contact. Static resistance was substantially lower than sliding resistance which confirms that sliding has a great effect on the conductivity of the contact. As expected, friction results displayed substantially lower friction coefficients for DLC – Steel and DLC – DLC contacts in comparison to Steel – Steel contact. The best material combination for electric application was High W-DLC – High W-DLC which exhibited very low electric resistance and friction coefficient with very low wear rate. The results gathered in this work indicate that DLC coatings have promising electric properties and show potential in future electric applications.
Os revestimentos DLC têm atraído o interesse da comunidade científica devido à sua combinação única de propriedades. São geralmente usados em várias aplicações sob a forma de revestimentos protetores uma vez que apresentam baixo atrito e elavada resistência ao desgaste. No entanto, existem poucas referências na literatura sobre valores de propriedades elétricas de revestimentos DLC e as suas potencialidades em aplicações eléctricas. O foco deste trabalho incidiu na determinação e análise das propriedades elétricas e tribológicas de revestimentos DLC comerciais. Neste trabalho foram estudados a resistividade, o atrito e a resistência ao desgaste de quatro revestimentos de DLC e de diferentes aços à temperatura por deslizamento alternativo a seco e diferentes condições de corrente continua. Os revestimentos DLC estudados neste trabalho foram Ti-DLC (5 e 10 % at.Ti ) e W-DLC (5 e 10 % at.W). Os testes realizados permitiram medir o coeficiente atrito e, simultaneamente, a resistividade no contacto, usando um tribómetro pino-disco e um equipamento de medição de tensão. A microscopia óptica e a interferometria de luz branca foram utilizads para a análise das pistas de desgaste. Os resultados das medições de resistividade mostraram que todos os revestimentos eram contudores eléctricos. Observou-se ainda que concentrações mais elevadas do elemento dopante conduziam a uma menor resistividade no contato. O contacto DLC – DLC também produziu medições de condutividade superior em comparação com o contacto DLC – aço. Os valores da resistividade estática são substancialmente inferiores aos obtidos por resistividade deslizante, confirmando-se assim que o deslizamento tem um grande efeito sobre a condutividade de contato. Tal como esperado, os valores do coeficientes de atrito obtidos para os pares DLC – aço e DLC – DLC são inferiors aos obtidos para o contato aço – aço. O par W-DLC – W-DLC com 10 % at. W foi o que apresentou maior potencial para aplicações elétricas, com muito baixos valores de resistividade elétrica e coeficiente de atrito e baixa taxa de desgaste. Os resultados obtidos neste trabalho indicam que os revestimentos DLC têm propriedades eléctricas promisoras, sendo potenciais materiais para futuras aplicações elétricas.

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Peng, Ting Chih, et 彭鼎智. « Depostion and Charactenstical of DLC film by electrodeposition ». Thesis, 2012. http://ndltd.ncl.edu.tw/handle/43161382062907263884.

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碩士
長庚大學
光電工程研究所
100
Diamond-like Carbon (DLC) films have numerous extraordinary advantages which are low friction factor, high hardness,and high insulation properties for satisfying significant application in the industrial domain. In this study, DLC films wee electrodeposited by on ITO glass substrate. The experimental equipment was carried out by using the graphite as the anode, ITO substrate as the cathode, and a mixture of acetic acid and DI water. The DLC film deposition parameters include DC potential, deposited temperature, solution concentration were varied being used to study the characteristics of DLC film in detail. The ammonia solution; NH4OH was added to change the properties of DLC thin film. As the nitrogen atom incorporated into the DLC structure increase, and the percentage of sp3 configuration in the structure of DLC shows decrease and the percentage of sp2 configuration increase From the dependence of depositing current density on depositing period (I-t plots), The relationship between each parameter and the properties of DLC thin film were investigated and discussed in detail. The SEM, Raman and XPS spectroscopy were used to analyze and inspect the film’s characteristics. For SEM photograph, it can be used to inspect the surface morphology and surface roughness. Raman spectra was used to inspect the microstructure of DLC film. It shows that there were two peaks located near 1350cm-1 and 1550cm-1, assigned as the characteristics peaks of DLC films. For XPS analysis, the XPS spectra show the nitrogen peak N1s at near 400 eV. That indicates the nitrogen atom was incorporated into the DLC structure.

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38

Huang, Kuen-Pyng, et 黃昆平. « Preparation of high hard DLC by ECR-CVD ». Thesis, 1997. http://ndltd.ncl.edu.tw/handle/74333601415897195728.

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碩士
國立中興大學
材料工程學研究所
85
This research concerns the production of DLC films of high hardness by means of ECR-CVD. During the experiments, the differences between the application of rf bias and dc bias are distinguished. On the one hand, when micro-wave and rf bias are applied simultaneously, the bombardment of high energy electrons on the substrate raises the temperature on the substrate. Thermal relaxation effect is thus resulted, and is unfavorable to the formation of carbon's sp3 bonds, The hardness of the films is consequently unable to be increased. On the other hand, when micro-wave of 600-1000W and dc bias of negative 200-300V are applied simultaneously, of hardness of the highly tetrahedral hydrogenated amorphous carbon (ta-C:H) can reach above Hv=6,224 kg/mm2. The plasma of acetylene untilized in the experiment is examined by means of Optical Emission Spectroscopy, and revealed that the gas of acetylene can be completely ionized into C2+ and H2+ ions, however, without C-H radical Such high quantity of carbon ions, lead to average film growth rate formation can be 0.6 μm/min . The result of this research can help produce efficiently the DLC films of high hardness. The only drawback is the high compressive stress that can cause the films to spall off, and this is what we need to work on in the future.

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Li, Jian-zheng, et 李建政. « Study on DLC Coating Polycarbonate Substrate by PECVD ». Thesis, 2004. http://ndltd.ncl.edu.tw/handle/76159829592578999391.

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碩士
國立中山大學
電機工程學系研究所
92
The purpose of this research was to deposit the protective diamond-like carbon (DLC) films on polycarbonate substrates for optical applications. In this study, by using the PECVD method is the better way to deposit DLC film on polycarbonate substrates since the whole process were performed at low temperature to avoiding any degradation of the adhesion of DLC film on polycarbonate substrates occurred at high temperature. In order to further increase the adhesion between the polycarbonate substrates and the DLC film, we deposited the SiO2 layer as an interlayer, and select HMDSO as precursor because it contain Si and O atoms. It is because that SiOx films that can be deposited from HMDSO/oxyzen feeds are relatively hard and against mechanical damages due to forming the glass-link structure. In addition, SiOx films are fully transparent in the UV range and decrease the difference of TCE ( thermal expansion coefficient) of PC and coating films. In experiments, it is preceded being focus on the analysis of Raman spectrum for the films grown at various CH4 gas fluxes, substrates bias voltages, Si-doping concentrations and the distance of electrode separation. The dependence of the intensity ratio of D-band and G-band ( ID/IG ) on the surface roughness, hardness and mechanical properties were investigated, and the adhesion of coating layer depends on the thickness of intermediate layer were studied under various substrate bias voltage. At least, the properties of diamond-like carbon (DLC) film coatings on phase-change recording media were characterized by Raman spectroscopy, atomic force microscope (AFM), UV-visible spectrometer and disc testers. The dependence of mechanical, optical and structural properties of DLC films included the characteristics of surface roughness, hardness, transmittance and electrical signals of discs on serveral DLC film thicknesses were investigated. Our experimental results indicate that DLC films provide a suitable coating to protect PC substrate and make it no difference for data stored on phase-change optical discs.

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YI, Wen-Yuan, et 易文元. « Application and Analysis of DLC Film Heat Transfer ». Thesis, 2009. http://ndltd.ncl.edu.tw/handle/95335542167098287799.

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碩士
聖約翰科技大學
自動化及機電整合研究所
97
The purpose of this research is to demonstrate the widespread application of Diamond-Like Carbon (DLC) membrane as an outstanding protective coating in cooling electronic devices, from design and testing perspectives. By applying DLC membrane on the surface of video cards cooling fins, the study has further to realize the cooling effects of DLC. The aim of this experimental work is to plate the aluminum heat sinks with various thickness range of DLC membrane (before sealing) to analyze its cooling effect at different stage. Having the nature of high heat conduction, DLC could significantly raising the heat transfer from GPU and video memory chips to the cooling fins than expected, providing unbeatable cooling effect which further sustain the efficiency & performance of graphic cards and extent service life of the graphic cards in general. Diamond-Like Carbon (DLC) membrane, from thickness, is categorized from 0.9μm, 1.6μm, 2.3μm, 3μm to 3.7μm respectively. Each specified measurements are taken into cross-analysis in comparing with those DLC membrane which is not plated on aluminum. The result of this experiment shows that the temperature is reduced by 5℃on the cooling radiator with aluminum-plated DLC membrane when comparing with non-plated DLC membrane. Furthermore, the value of thermal resistance also reduces about 26% on aluminum-plated DLC membrane. The thinner the DLC membrane is, the possible the thickness configuration is uneven which causes the value of thermal resistance in comparatively inconstant at the low heating watt. With tests, when the higher watt is induced, the DLC membrane will thus performs in reducing thermal resistance. By comparing the temperature of cooling fins in matching with differential thickness of DLC membrane, research shows that 3.7μm reveals the lower temperature than others. Nevertheless, the test data also demonstrates that the heat source temperature in various thickness of DLC membrane may not have very much disparity, roughly 0.9℃.

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Lin, Yi-nan, et 林益楠. « Study on low voltage electrodeposition of DLC films ». Thesis, 2005. http://ndltd.ncl.edu.tw/handle/92201065243410134090.

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碩士
國立中山大學
電機工程學系研究所
93
In the early years, DLC films was deposited at high voltage applied by electrochemical method. In this study, DLC film was deposited alternatively at low voltage applied using electrodeposition. The ITO glass substrate was used as the cathode, and graphite sheet was the anode. The electrolyte is a mixture of acetic acid with DI water. The applied voltage was mere 2.1 volt during the electrochemical process. For investigating the structure of deposited films, the deposited DLC layers were characterized by Fourier transform infrared (FTIR), Scanning electron microscope (SEM) and Raman spectrometer. The SEM results show that the DLC films have a rough surface and their roughness increased with longer in deposition time as well as raise applied voltage. The Raman spectra shows distinct broad characteristic peaks at ~ 1336 cm-1 (D-peak) and ~ 1601 cm-1 (G-peak), which indicate the disordered graphite-like structure and the graphite structure, respectively. While the bond angles occur to bend or the increase the content of sp3 bonds in DLC film, both the G-peak and the D-peak shift to the lower wave numbers. Peaks at ~ 2956 and ~ 2917 cm-1 found in FTIR measurement were used to recognize the existence of sp3 and sp2 combined carbon atoms in the films. Based on above results, it could conclude that the DLC film could be prepared by electrodeposition under low applied voltage.

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42

Wu, Chia-Wei, et 吳家偉. « The effect of ECR-CVD process on DLC films ». Thesis, 2003. http://ndltd.ncl.edu.tw/handle/59713114386614721174.

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碩士
國立成功大學
材料科學及工程學系碩博士班
91
Diamond-Like carbon (DLC)films have received a considerable amount of attention recently due to their chemical stability，high optical transparency and hardness .These properties make the films suitable for a number of applications such as protective and anti-reflection coating，wear resistant overcoat and biocompatible coatings .However，the sp3 bonding of carbon atoms in the amorphous structure are severely distorted and strained，resulting in a large compressive stress within the films . Amorphous hydrogenated diamond-like carbon films were deposited on SKD61 by electron cyclotron resonance chemical vapor deposition (MW ECR-CVD)using C2H2 and Ar as gas sources .The properties of the film were investigated by electron spectroscopy for chemical analysis(ESCA)、Auger electron spectroscopy(AES)、scanning electron microscope (SEM)、transmission electron microscope(TEM)、atomic force microscope(AFM)、Raman spectroscopy and pin on disk tribometer . The results reveal that the structure、adhesion 、hardness and wear rate of the films depend its process parameters bias and C2H2 flow rate .With the bias increasing，the ratio of sp3 to sp2 and hardness is increasing . With the C2H2 flow rate increasing，the ratio of sp3 to sp2 and hardness is increasing.

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Lee, Ming-Shiue, et 李明勳. « Deposition and characteristical of DLC film by electrodeposition technique ». Thesis, 2010. http://ndltd.ncl.edu.tw/handle/99503757625446554482.

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碩士
國立中山大學
電機工程學系研究所
98
Diamond-like carbon (DLC) film exhibits an extreme hardness, low friction coefficient, chemical stability, heat conductivity, high resistance, and high optical transparency. There properties lead to remarkable applications such as protective and anti-reflection coating, wear resistant overcoat and biocompatible coatings. In this study, Diamond-like carbon films were deposited by electrodepsoition technique, and the deposition parameters include DC potential, deposited temperature, the concentration of electrolyte were varied to study the characteristics, microstructure and the composition of DLC film. In addition, the optimizing deposition was revealed and discussed in detail. The Diamond-like carbon film were deposited by electrodepsoition technique onto the ITO glass substrates, and the deposition conditions were preset in the range as the applied voltage from 50V and 250V, low deposition temperature within 35℃to 50℃ and a mixture of acetonitrile and deionized water with the concentrations of acetonitrile between 0.2% and 3.2%. Scanning electron microscopy can make an insight into the surface morphology also to reveal the uniformity of the DLC films. For the I-t curves of DLC film growth, it can be used to study of the growth mechanism by correlation the surface morphology observed by Scanning electron microscopy (SEM). The transmission, refraction index and optical band gap of DLC film was measured by the N &K analyzer. Finally, the hydrogen content, composition and microstructure of DLC films were characterized by the FTIR and XPS analyze In experimental work, the properties of DLC film obtained depends on a verity of growth parameters such as applied voltage, the concentration of electrolyte and deposition temperature. With the increase of the applied voltage, it increases with the growth rate of deposited films. That was also observed in the increase of concentration and temperature. As increase the film’s thickness, the film surface becomes to the light yellow brown color, and which also causes to increase the refractive index, decrease the transmission rate, reduce the optical band gap, and decrease the amount of C-H bond and the C-N bond increase simultaneously. According to above results, DLC film deposited using the electrolyte of acetonitrile was more suitable used for coating on Si –based optoelectronic devices such as solar cell to be a protective layer and/or anti-reflection layer. Additionally, for the nitrogen doing in DLC film, it can increase the adhesion and the friction of film to utilize for mechanic industry and to develop as the window layer of solar cells. Although there are few N-content incorporated in the DLC film, and that limits its applications. However, it still has a high potential used for solar cells and leads to advanced study in the future.

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44

Kuo, Jui-Kang, et 郭瑞剛. « Investigation of DLC-film wear by cathodic arc deposition ». Thesis, 1999. http://ndltd.ncl.edu.tw/handle/55110576322533352403.

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碩士
華梵大學
機電工程研究所
87
ABSTRACT This paper describes the characteristics of the DLC film evaporated by graphite cathodic arc method and it’s tribological behavior in reciprocating dry sliding with 4032 Al-alloy, 52100 steel and Al2O3. In addition, the wear mechanisms of the film and counterbody are discussed. The influence of process parameter and loading on wear is also studied. The result shows that the DLC film obtained under low Ar evaporation condition has a better performance on hardness. Besides, the thickness of the DLC film increases with the increase of negative bias voltage on substrate under low Ar flow condition during evaporation. The Raman spectrum analysis shows that the DLC film has wide and flat spectrum region at the wavelength of 1560 cm-1 of G band and 1350 cm-1 of D band. It means that the DLC film has much graphite-like SP2 bonding and a little amorphous DLC SP3 bonding. The wear-resistance of the DLC film increases with the decrease of the Ar flow during evaporation. Furthermore, the 52100 steel counterbody during sliding wear exhibits a best wear performance, which is due to high hardness and good surface roughness. The main wear mechanisms are adhesion wear and fatigue wear for 4032 Al alloy and 52100 steel and brittle fracture and fatigue wear for Al2O3 while the principal wear mechanisms of DLC film are abrasive wear and fatigue wear.

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45

Chang, Ya-Chen, et 張雅軫. « A Study on the Characterization of Silver-containing DLC Film ». Thesis, 2010. http://ndltd.ncl.edu.tw/handle/17587053481315660851.

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碩士
國立高雄應用科技大學
模具工程系
98
The silver-containing DLC films are deposited on glass using magnetron reactive sputtering. The watt of input energy is applied as main process variable to obtain 1~2 μm thick films. The basic properties such as hardness, electric resistivity and surface roughness are evaluated by hardness tester, 4-probe resistivity tester and atomic force microscope (AFM), respectively. The X-ray diffraction (XRD), scanning electron microscope (SEM), Raman spectroscope and transmission electron microscope (TEM) are used to examine the microstructures and bonding characteristic and growth morphologies of DLC films. The anti-bacterium test and contact angle test are undertaken to analyze the anti-bacterium capabilities of silver-containing DLC films. The results indicate that the thickness and agglomerative and silver content and ID/IG of the films and surface roughness increase with input watt, while hardness and electric resistivity decrease with input watt. The anti-bacterium tests show that the anti-bacterium ability increases with silver content in DLC and the anti-bacterium rate of 98％ is obtained with 71.46％ of silver content in DLC. In addition, the contact angles also increase with silver contents in DLC, which may assist in capability of anti-bacterium.

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46

Tsai, Yun-Kuang, et 蔡昀光. « Study on the electrodeposition of metal-doped DLC thin film ». Thesis, 2011. http://ndltd.ncl.edu.tw/handle/62196587810684379533.

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碩士
國立中山大學
電機工程學系研究所
99
Recently, synthesis of Diamond-Like Carbon (DLC) films has received considerable interest. Owing to their similar characteristics of diamonds, such as extreme hardness, chemical stability, and high heat conductivity etc, DLC films are regarded as one of the most promising materials. But the practical applications have been limited due to their high internal stress and insufficient adhesion at the interface between DLC film and substrate. Several methods used to the deposition of Me-DLC films have been proposed. Studies have shown that the internal stress was released and the adhesion also improved by doping metallic element into DLC films. Conventionally, metal incorporation in DLC films were prepared by vapor deposition. The requirement of high vacuum equipment makes the process complicated. Besides, there are many merits in electrodeposition, such as low cost, simplicity of experimental set up, and availability for deposition on complex shapes substrate in large area. In this study, electrodepositing technique was used to synthesize the amorphous Cu-DLC films deposited on ITO substrate, in which the pH value of electrolyte varied, to study the characteristics and the composition of DLC films. According to the I-t curves of deposition, the end of current density was used for the impedance comparison of films. With the addition of Cu, the resistance of the electron transportation in Cu-DLC was reduced, and the awl-shaped surface morphology was observed by AFM measurement, which could enhance the electron field emission properties of thin films. For Raman analysis, the effect of Cu addition would promote the sp2 bonding； this result corresponds with the increasing ID/IG value. It indicates that film becomes graphitization due to the addition of Cu and leads the shift of G-peak position toward lower wavenumber. ESCA spectra of C1s and Cu2p indicate no obvious evidence of Cu-C formation. The sp2/(sp2+sp3) ratio increases with the pH value. In addition, we found that Cu-DLC in acidic environmental condition, or doping as [Cu(NH3)n]2+ complex is more conducive to the growth of copper metal in DLC films, and has the lowest optical band gap value deduced by n&k analyzer. Finally, we discussed the thin film growth mechanisms and the characteristic of electron field emission for the applications in the future.

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47

Yeh, Wen-ting, et 葉文挺. « The Influence of the DLC Coating Parameters on th interface ». Thesis, 2001. http://ndltd.ncl.edu.tw/handle/31537161392636452987.

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48

Lie, Sim-hong, et 賴信宏. « Study on the DLC Film Deposition Microdrill by ECR-CVD ». Thesis, 2004. http://ndltd.ncl.edu.tw/handle/48318100422888494246.

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碩士
國立中山大學
電機工程學系研究所
92
A hybrid physical vapor deposition- electron cyclotron resonance-chemical vapor deposition (PVD-ECRCVD) coating system HBS900 is used to deposit the diamond-like carbon (DLC) film on the microdrills. It could keep friction low results in improving the productivity of the drill holes on the printed circuit board (PCB). In order to improve the adhesion strength of the DLC films,functionally gradient Ti/TiN/TiCN supporting multilayer were pre-deposited initially on the microdrills. The hard coatings of titanium nitride (TiN) and titanium carbonitride (TiCN) as multilayer are deposited by PVD with high rate coating sources based on the principle of electrical arc vaporization and magnetron sputtering process. The on it following dry lubricant coating is composed of amorphous, diamond like carbon (DLC) deposited by ECRCVD plasma in the same recipient. The structural characteristics of DLC films were investigated by Raman spectroscopy and standard scratch and pin-on-disk test.The properties of DLC films coating on the microdrills are obtained and summarized as follows: excellent adhesion 65N, and coefficients of friction less than 0.15. After micro-hole drilling, we obtained the high quality drilled hole from the inspection of roughness and nailheading. As a result of adapting a microdrill coated with DLC film, the drilling lifetime was significantly improved to reach about 2.5 times than that of the uncoated one.

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49

Lin, Honda, et 林宏達. « Effect of Ti incorporation on the properties of DLC film ». Thesis, 2008. http://ndltd.ncl.edu.tw/handle/86438926764749404341.

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碩士
國立清華大學
材料科學工程學系
96
In this work, Ti-doped diamond like carbon thin films (DLC) were synthesized by two methods. In the first method, Ti was incorporated into DLC by a metal vapor vacuum arc system (MeVVA). In the second method, Ti-doped DLC was synthesized by filtered a cathodic vacuum arc plasma system (FCVA). Since the structure of Ti-doped DLC was destroyed by high-energy ion implantation, annealing was used to recover the structure of Ti-doped DLC. The XPS analysis demonstrates that C 1s core-level of Ti-doped DLC incorporated by MeVVA shifts towards lower binding energy. The auger electronic spectra show that the depth-profiles in these methods are different. From the TEM observation, nano-crystalline clusters appear in Ti-doped DLC incorporated by MeVVA, and a multi-layer structure appears in the Ti-doped DLC synthesized by FCVA. The Raman spectra show that ID/IG ratio increase with the Ti content. The rising ratio implies that the sp3 bonds increase with Ti content. The extremely low surface roughness and improved electrical conductivity show that Ti-doped DLC has practical applications.

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Huang, Yu-Che, et 黃昱哲. « Fabrication and Characterization of the Electrodes on DLC Solar Cells ». Thesis, 2010. http://ndltd.ncl.edu.tw/handle/4yaa3r.

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碩士
國立臺北科技大學
材料及資源工程系研究所
98
After the industrial revolution, a large number of the hidden resources on the earth are developed to enhance the quality of human life. However, the side effects of these actions induce not only the shortages of fossil energy but also the environmental pollution on the earth. Solar cells convert light into electrical energy which can slow down these issues. The high light transmittance and electric conductivity of indium tin oxide (ITO) films are deposited by DC magnetron sputtering method, the main purpose of efficient collection of solar cells after light illumination generated by the electrical carriers, which is designed as the electrodes of p type DLC (Diamond like-Carbon) solar cells to enhance the conversion efficiency of the battery. The optimal properties of ITO films prepared by 40W are 80 nm that the optical transmission and energy band of the films are about 93% and 3 eV, respectively. The optical properties of ITO thin films applied on solar cell are very important. For the visible light to pass through the ITO thin film, high transmittance of the material is essential. In this study, an 80nm thick ITO thin film prepared with 40W sputtering power is applied on the p-DLC solar cell. Result indicates that solar cell without ITO thin film deposited in its structure possesses lowest efficiency. As compared with metal electrode with finger shape directly onto the p-DLC/n-Si devices, devices with ITO/p-DLC/n-Si/Al show 1.22% conversion efficiency for more light absorbed by the devices and more photo-generation carriers effectively collected by the ITO electrode. Even though the ITO thin films could collect photo-generation carriers, the series resistance of ITO electrode with about 32.26 Ω is still too high for the cell performance. The structure of cell with Al/ITO/p-DLC/n-Si/Al is 3.41% of the conversion efficiency possibly due to the lower resistivity of the Al finger electrodes series connected with modified parallel ITO electrodes onto P-DLC film. The series resistance of the combined electrodes in this device computed by the I-V curve is about 8.81 Ω. The maximum of quantum efficiency of Al/ITO/p-DLC/n-Si/Al solar cell is at the wavelength of 700 nm and about 76%.

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