Dissertations / Theses on the topic 'Blank coating'

Ceria (CeO2), chromia (Cr2O3), yttria-stabilized zirconia (Y2O3-ZrO2), and sodium cerium oxide (Na2CeO3) were used as barrier coatings on Ufala, an alumina-based ceramic refractory, to determine if they were effective at increasing the life of the refractory in a high-temperature black liquor gasification environment. The ceria, chromia, and yttria-stabilized zirconia coatings were applied at atmospheric pressure using a coating applicator at the Institute of Paper Science and Technology at the Georgia Institute of Technology. The sodium cerium oxide coatings in addition to the three other coating types were applied under atmospheric pressure at C3 International Technologies in Alpharetta, GA. The coated refractory, as well as a set of uncoated refractory used for baseline analysis, were tested using molten synthetic smelt at 1000C for 36 hours. Uncoated refractory samples were also tested for 12, 72, 120, and 168 hours in order to make a kinetic reaction rate determination. The refractory were analyzed using gravimetric and dimensional analysis, X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy to determine the severity of the physical changes that occurred after exposure to molten smelt. The data gathered from these experiments were not able to conclude that barrier coatings are sufficient to impede corrosion of the Ufala refractory material in molten smelt.

The sheet metal forming process basically involves the shaping of sheet metal of various thickness and material properties into the desired contours. This metal forming process has been extensively used by the automotive industry to manufacture both car panels and parts. Over the years numerous investigations have been conducted on various aspects of the manufacturing process with varied success. In recent years the requirements on the sheet metal forming industry have headed towards improved stability in the forming process while lowering environmental burdens. Therefore the overall aim of this research was to identify a technique for developing lubricant formulations that are insensitive to the sheet metal forming process. Due to the expense of running experiments on production presses and to improve time efficiency of the process the evaluation procedure was required to be performed in a laboratory. Preliminary investigations in the friction/lubricant system identified several laboratory tests capable of measuring lubricant performance and their interaction with process variables. However, little was found on the correlation between laboratory tests and production performance of lubricants. Therefore the focus of the research switched to identifying links between the performance of lubricants in a production environment and laboratory tests. To reduce the influence of external parameters all significant process variables were identified and included in the correlation study to ensure that lubricant formulations could be desensitised to all significant variables. The significant process variables were found to be sensitive to die position, for instance: contact pressure, blank coating of the strips and surface roughness of the dies were found significant for the flat areas of the die while no variables affected friction when polished drawbeads were used. The next phase was to identify the interaction between the significant variables and the main lubricant ingredient groups. Only the fatty material ingredient group (responsible for the formation of boundary lubricant regimes) was found to significantly influence friction with no interaction between the ingredient groups. The influence of varying this ingredient group was then investigated in a production part and compared to laboratory results. The correlation between production performance and laboratory tests was found to be test dependant. With both the Flat Face Friction test and the Drawbead Simulator unaffected by changes in the lubricant formulation, while the Flat Bottom Cup test showing similar results as the production trial. It is believed that the lack of correlation between the friction tests and the production performance of the lubricant is due to the absence of bulk plastic deformation of the strip. For this reason the Ohio State University (OSU) friction test was incorporated in the lubricant evaluation procedure along with a Flat Bottom Cup test. Finally, it is strongly believed that if the lubricant evaluation procedure highlighted in this research is followed then lubricant formulations can be developed confidently in the laboratory.

In this study, electrically conductive coating materials composed of epoxy resin and carbon black (CB) were prepared by applying two different mixing techniques (Grinding and Mechanical Mixing). The effect of carbon black addition, ultrasonication, mixing type and surface modification of carbon black on the morphologies, electrical and mechanical properties of the composites were investigated. According to test results, Grinding Method is much more efficient and for this method, percolation concentration was found as 2 vol %. The electrical resistivity value obtained at this composition is around 107 ohm.cm. Also, for the samples prepared by Grinding Method, the hardness increased by adding conductive filler, but the impact energy and adhesive strength decreased with increasing carbon black content. Ultrasonication was applied to the samples containing 2 vol % CB obtained by Grinding Method to reduce the electrical resistivity further. Three different ultrasonic mixing times were tried, however, no positive effect was observed on electrical and mechanical properties. Since the addition of carbon black has a negative effect on the processability of the mixture, it was aimed to obtain desired conductivity value at lower percolation concentration by modifying carbon black surface with different silane coupling agents and formamide. The best result in terms of electrical conductivity was obtained for the materials produced with formamide treated carbon black by Grinding Method. At 1 vol % concentration, the electrical resistivity was found as approximately 106 ohm.cm which is three orders smaller than the resistivity of materials prepared with untreated carbon black.

Suck, squeeze, bang, blow! The efficiency and performance of a gas turbine engine relies on the ability to maintain high gas pressure ratios, throughout each stage of the compressor. To do this, engine manufacturers must minimise gas leakage over compressor blade and seal fin tips. Increasing the efficiency of the gas turbine engine is an area of enormous importance to engine manufacturers worldwide. The rewards are obvious when it is considered that a modest improvement of 0.5 to 1% to the Specific Fuel Consumption (SFC) can translate to huge savings on fuel costs. One way in which engine manufacturers are looking to do this is through the use of abradable seals, which are used to help seal the engine and reduce air leakage over blade tips. In an attempt to gain a fundamental understanding of abradable materials, this thesis discusses research carried out as part of an Engineering Doctorate. The research focuses on three key topic areas, identified as necessary for generating a robust understanding of the complete coating life. The research carried out within this EngD programme has helped to generate a fundamental understanding of abradable materials by focusing on three key topic areas: i) Development of Test Methodology ii) Definition of Performance Drivers iii) Implementation of Technology Within these topic areas programmes of work have been carried out, which aim to fill gaps in current knowledge and provide the knowledge and techniques for future coating development. Significant advances have been made in all aspects of abradable understanding and the knowledge generated is now being successfully implemented within the Rolls-Royce Abradable Strategy. As the demands from regulators and airlines for greater aero engine performance increase, the need for reliable and effective compressor sealing will become evermore critical. The knowledge and techniques developed within this EngD programme will enable further detailed understanding of the science of abradable materials.

A study of thermal, structural, electrical and optical characteristics of molybdenum black surface coatings on various substrates has been made. The suitability of these coatings for use as selective absorbers for solar collector applications has been assessed. Molybdenum black (Mo black) coatings were prepared by electrodeposition (on aluminium) and a chemcial conversion method (on zinc and electroplated cobalt on nickel plated copper substrates). The solar absorptancer (αs) and thermal emittances (εth) of the coatings were determined from room temperature spectral reflectance measurements in the solar (0.3 to 2.5μm) and infrared regions (2.5 to 50 μm) respectively. The effect of different preparation parameters and substrate pretreatments on the spectral selectivity has been investigated in order to optimize the thermal performance. The spectral selectivity is related to the Mo-black coating thickness and surface roughness together with the microstructure, of the substrate and the intermediate layer. Dip coatings on polished zinc have significant selectivity (αs/ εth = 8.4 when αs = 0.76). The absorptance of the dip coatings is increased to 0.87 with εth = 0.13 by chemical etching of zinc prior to coating deposition. For coatings on electroplated cobalt on nickel plated copper (cobalt (NC) substrate), an absorptance as high as 0.94 has been obtained with an emittance value 0.3. By using an addition agent in the plating solution of cobalt the high emittance can be reduced to 0.1 with αs = 0.91 giving a coating with a relatively high efficiency (82.5%) for photo-thermal energy conversion. A study of the surface composition and microstructure of the coatings has been made using scanning and transmission electron microscopy together with electron diffraction, X-ray diffraction and X-ray photoelectron spectroscopy. The structural investigations indicate that Mo-black coatings contain polycrystals of orthorhombic Mo4O11 with a small proportion of Ni(OH)2. Presence of water and also Mo4O11 in the coatings are evident from IR spectroscopy study. The bandgap of the coating has been determined from optical transmission spectra (1.66 eV) and also from reflectance spectra (0.85 eV). The discrepancy between these two values has been discussed. The refractive indices of the coatings have also been estimated. The band gaps and refractive indices are found to be related to the spectral selectivity of the coatings. The durability test of the coatings shows that the coatings on etched zinc are more resistant to heat treatment than the coatings on unetched zinc. The coatings on cobalt (NC) substrates also show good stability for relatively short periods at temperatures ~400ºC. A study of the electrical properties of Mo-black coatings suggests that at electrical field strengths (greater than 106v/m the dominant conduction process is of the Poole-Frenkel type. The activation energy of the conduction process has been estimated to be -0.56 eV at higher temperatures. The effect of heat treatment on the electrical properties of the coatings has been examined. The dielectric constant of Mo-black has been estimated from A. C. measurements. At high frequency (20 kHz) the value of the dielectric constant is about 4.0.

SAAB AB coats a part of their magnetron with black chromium to enhance its ability to radiate thermal radiation. Today an electrodeposition process that has hexavalent chromium as its main component is used, but hexavalent chromium is carcinogenic and will be prohibited. This project examines if an electrolyte based on trivalent chromium can result in a black chromium coating. The project was divided into in four experimental parts: investigation of the adhesion on copper, the effect on color if copper was added to the electrolyte and investigation of the process parameters with and without cooling of the electrolyte. It was concluded that a black chromium coating can be deposited from a trivalent electrolyte. Heating the sample after plating and addition of iron or copper in the electrolyte darkens the color but addition of copper can not produce a coating on copper substrates with good adhesion. To examine how the coating thickness and emissivity vary with the current density, electrolyte temperature and plating time, the coatings thickness and emissivity were measured for different settings. It was shown that the coating thickness increased with plating time and current density until a critical value was reached and the coating started to peel off. No correlation between the emissivity and process parameters could be shown. It is suggested that further experiment are conducted to investigate if a variation in pH- value effects the emissivity. Based on the results and conclusions it is recommended that the addition of iron to the electrolyte is further examined.

Spider silk is one of the most versatile material.s in nature with great mechanical properties, exceeding some of the best man made materials. Native and synthetically produced silk has been used in a wide array of applications throughout the history of mankind including nets, bandages and cloths. It is recognized that spider silk can be a suitable replacement material for many existing materials such as ropes, body armor, parachutes and biodegradable bottles - all of which could show cost and environmental 4 benefits relative to other currently used man made materials. An added advantage to these types of applications is the potential for the products to have intrinsic antimicrobial activity. Studies have demonstrated a level of antimicrobial activity in native silk, a property that may have evolved in order to resist microbial decomposition, to protect developing eggs, and to resist decomposition or destruction by predators, parasites, or fluctuations in the environment. In this study, the novel aqueous glue coating peptides found on the silk fiber of the black widow spider, spider coating peptide 1 and 2, were investigated. Using circular dichroism, it was determined that SCP-1 and SCP-2 display predominantly alpha-helical secondary structures. In temperature gradient studies, SCP-1 is structurally stable at high temperatures while SCP-2 unfolded and lost its alpha-helical structure. The two peptides remained structurally stable both in an acidic and basic environment. This study was the first to characterize the secondary structure of the peptides found coating various silk fibers in Latrodectus hesperus, the black widow spider. The function of the SCPs is unknown but has-been hypothesized to potentially have antimicrobial properties. We investigated this role and found no significant antibacterial activity of the peptides against Escherichia coli and Bacillus subtitlis in growth studies. This study is the first to investigate the functional role of SCPs.

Spider silk is one of the most versatile material.s in nature with great mechanical properties, exceeding some of the best man made materials. Native and synthetically produced silk has been used in a wide array of applications throughout the history of mankind including nets, bandages and cloths. It is recognized that spider silk can be a suitable replacement material for many existing materials such as ropes, body armor, parachutes and biodegradable bottles - all of which could show cost and environmental 4 benefits relative to other currently used man made materials. An added advantage to these types of applications is the potential for the products to have intrinsic antimicrobial activity. Studies have demonstrated a level of antimicrobial activity in native silk, a property that may have evolved in order to resist microbial decomposition, to protect developing eggs, and to resist decomposition or destruction by predators, parasites, or fluctuations in the environment. In this study, the novel aqueous glue coating peptides found on the silk fiber of the black widow spider, spider coating peptide 1 and 2, were investigated. Using circular dichroism, it was determined that SCP-1 and SCP-2 display predominantly alpha-helical secondary structures. In temperature gradient studies, SCP-1 is structurally stable at high temperatures while SCP-2 unfolded and lost its alpha-helical structure. The two peptides remained structurally stable both in an acidic and basic environment. This study was the first to characterize the secondary structure of the peptides found coating various silk fibers in Latrodectus hesperus, the black widow spider. The function of the SCPs is unknown but has-been hypothesized to potentially have antimicrobial properties. We investigated this role and found no significant antibacterial activity of the peptides against Escherichia coli and Bacillus subtitlis in growth studies. This study is the first to investigate the functional role of SCPs.

Le carbone-suie, ou “black carbon” (BC), contribue au réchauffement climatique avec un forçage positif de l’ordre de +1.1 W m-2 dont l’incertitude reste haute (de l’ordre de 90%). Ce forçage s’effectue à travers l’interaction aérosol-radiation et l’interaction aérosols-nuage. Ces deux mécanismes sont affectés par le degré de mélange des particules du BC avec divers matériaux non-réfractaires et non-absorbants. Cependant, les estimations du forçage radiatif considèrent rarement les effets du mélange interne. Par ailleurs le rôle du BC comme noyau glaçogène qui influence l’interaction aérosol-nuage est largement inconnu. L’objectif de cette thèse est de mieux comprendre les mécanismes par lesquels le degré de mélange interne du BC influence la variabilité des propriétés optiques du BC et les propriétés d’activation des noyaux glaçogènes contenant du BC.Dans le premier chapitre de cette thèse, nous avons exploré la variabilité spatiale et saisonnière du coefficient d’absorption massique -mass absorption cross-section (MAC)- dans l’atmosphère en Europe. Les valeurs de MAC sont déterminées à partir de concentrations de carbone élémentaire et de coefficients d’absorption observée à différentes stations d’observation européenne du réseau ACTRIS (Aerosol, Cloud and Trace gases Research InfraStructure). Les résultats montrent une faible variabilité spatiale du MAC avec une moyenne de 10 ± 2.5 m2 g-1 à 637 nm de longueur d’onde qui peut être considérée comme représentative du BC en Europe. Le cycle saisonnier du MAC est probablement lié à la composition chimique de l’aérosol et son état de mélange, qui provoque une augmentation du MAC.Dans le second chapitre on s’est intéressé au lien entre l’absorption du BC et son état de mélange après transport sur longue-distance. Ce travail se base sur des mesures effectuées dans le cadre du projet CLIMSLIP (CLimate IMpact of Short-Lived Pollutants and methane in the Arctic). Une campagne de mesure a été conduite sur la station de recherche Zeppelin au Svalbard, Norvège en Avril 2012. Les données acquises avec un Single Particle Soot Photometer (SP2) révélaient que le BC est généralement présent en mélange interne dont l’épaisseur moyenne de la couche superficielle de matériel non-absorbant est de 47 nm pour des particules de BC de diamètre compris entre 170 et 280 nm. Ce mélange interne conduit à une augmentation d’absorption de 46%. Elle entraîne cependant une diminution relativement faible de l’albédo de simple diffusion, de l’ordre de 1%.Enfin, la capacité du BC à agir comme noyaux glaçogène pour la formation de cristaux de glace a été étudiée sur le site de haute altitude du Jungfraujoch (Suisse) dans le cadre du “cloud and aerosol characterization experiment” (CLACE) en 2013. Les différents éléments du nuage étaient séparé à partir d’une prise d’entrée type ice-CVI connectée au SP2. Ce dispositif permet de sélectionner uniquement les cristaux de glace et quantifier la fraction de BC activée. Une réduction de la présence de BC dans les résidus de glace a été observée. Des mesures de l’épaisseur de la couche de mélange interne des particules contentant du BC ont montré que les résidus de cristaux de glace présentaient des enrobages bien plus épais comparée à l’aérosol total.Les résultats obtenus au cours de ce travail ont permis de mieux comprendre l’impact du degré de mélange interne sur les propriétés optiques du BC et sur son rôle dans la formation de cristaux de glace. Les propriétés optiques du BC évoluent en fonction de la saison, tandis que la formation d’une couche superficielle amplifie sa capacité d’absorption du rayonnement solaire. De plus, cette étude souligne l’importance du vieillissement atmosphérique du BC sur sa capacité à servir de noyau de nucléation de la glace. Enfin, il fournit une avancée au sujet des propriétés sensibles mesurées dans l’atmosphère avec des techniques innovantes qui permettront la simulation plus précise du forçage radiatif
Black carbon (BC) induces a warming effect (RFBC = +1.1 W m-2 ± 90%) through two main pathways: aerosol-radiation interaction (RFari) and aerosol-cloud interaction (RFaci). Both BC-radiation and BC-cloud interaction are affected by the mixing of black carbon with other non-refractory and non-absorbing matter present in the atmosphere. An estimation of the global radiative forcing of BC rarely accounts for internal mixing of BC while the net global cloud radiative forcing is sensitive to assumptions in the initiation of cloud glaciation, which is mostly unknown for black carbon particles. Within this thesis we investigated the variability of the light absorbing properties of black carbon, the mixing of black carbon, and the impact on light absorption and ice activation.In the first part of this thesis we investigated the spatial and seasonal variability of the mass absorption cross section (MAC) over Europe. MAC values were determined from ambient observations of elemental carbon mass concentrations (mEC) and absorption coefficients (σap). The data had been acquired during several years at different background ACTRIS supersites spread over Europe. Site specific MAC values were found to be spatially homogeneous, suggesting that the overall MAC average 9.5 ± 1.9 m2 g-1 at a wavelength of 637 nm might be representative of BC at European background locations. The MAC values showed a distinct seasonal cycle at every station. This seasonality might be related to chemical composition and aging. We observed that the MAC value has a linear and positive proportionality with the non-absorbing matter mass fraction.The second part of the work focuses on the coating acquisition of BC and the induced absorption enhancement after long-range transport. Within the CLIMSLIP (climate impact of short-lived pollutants and methane in the Arctic) project field experiments were conducted at the Zeppelin research site in Svalbard, Norway, during the Arctic spring. SP2 data were used to characterize the BC size distribution and mixing. BC containing particles having a core diameter between 170 and 280 nm were found to have a median coating thickness of 47 nm. The relationship between coating thickness and BC absorption was simulated. The observed coating thickness enhanced the mass absorption cross section by 46%, which led to a decrease of less than 1% in the single scattering albedo.In the final part of this work, the role of black carbon as ice nuclei in mixed phase clouds was investigated at the high elevation measuring site Jungfraujoch (Switzerland) during the cloud and aerosol characterization experiment (CLACE) held in 2013. The ice-CVI inlet and a single particle soot photometer were used to select and quantify the ice activated BC particles. According to the observations, BC containing particles were depleted in the ice residuals. The activation efficiency showed a size dependency, with larger BC containing particles being activated more efficiently compared to smaller ones. Activated BC cores having a diameter between 170 and 240 nm showed a larger coating thickness (median = 53 nm) compared to the total aerosol (median = 16 nm).The results obtained in this thesis shed new light on the effect of the mixing state on the optical properties and cloud activation of black carbon particles. Absorbing properties of BC showed a distinct seasonal pattern, while aging was found to consistently increase its absorption behavior. However, black carbon was found not to act as ice nuclei in low tropospheric mixed-phase clouds, where the coating thickness might play a role in the activation efficiency. This work provides freshly determined physical properties derived from ambient observations that will improve the accuracy of future aerosol and cloud radiative forcing estimations

The fabrication of low cost, high efficiency solar cells is imperative in competing with existing energy technologies. Many research groups have explored using III-V materials and thin-film technologies to create high efficiency cells; however, the materials and manufacturing processes are very costly as compared to monocrystalline silicon (Si) solar cells. Since commercial Si solar cells typically have efficiencies in the range of 17-19%, techniques such as surface texturing, depositing a surface-passivating film, and creating multi-junction Si cells are used to improve the efficiency without significantly increasing the manufacturing costs. This research focused on two of these techniques: (1) a tandem junction solar cell comprised of a thin-film perovskite top cell and a wafer-based Si bottom cell, and (2) Si solar cells with single- and double-layer silicon nitride (SiNx) anti-reflection coatings (ARC). The perovskite/Si tandem junction cell was modeled using a Matlab analytical program. The model took in material properties such as doping concentrations, diffusion coefficients, and band gap energy and calculated the photocurrents, voltages, and efficiencies of the cells individually and in the tandem configuration. A planar Si bottom cell, a cell with a SiNx coating, or a nanostructured black silicon (bSi) cell can be modeled in either an n-terminal or series-connected configuration with the perovskite top cell. By optimizing the bottom and top cell parameters, a tandem cell with an efficiency of 31.78% was reached. Next, planar Si solar cells were fabricated, and the effects of single- and double-layer SiNx films deposited on the cells were explored. Silicon nitride was sputtered onto planar Si samples, and the refractive index and thicknesses of the films were measured using ellipsometry. A range of refractive indices can be reached by adjusting the gas flow rate ratios of nitrogen (N2) and argon (Ar) in the system. The refractive index and thickness of the film affect where the minimum of the reflection curve is located. For Si, the optimum refractive index of a single-layer passivation film is 1.85 with a thickness of 80nm so that the minimum reflection is at 600nm, which is where the photon flux is maximized. However, using a double-layer film of SiNx, the Si solar cell performance is further improved due to surface passivation and lowered surface reflectivity. A bottom layer film with a higher refractive index passivates the Si cell and reduces surface reflectivity, while the top layer film with a smaller refractive index further reduces the surface reflectivity. The refractive indices and thicknesses of the double-layer films were varied, and current-voltage (IV) and external quantum efficiency (EQE) measurements were taken. The double-layer films resulted in an absolute value increase in efficiency of up to 1.8%.

Macromolecular biomaterials often require covalent crosslinking to achieve adequate stability and mechanical strength for their given application. However, the use of auxiliary chemicals may be associated with long-term toxicity in the body. Oppositely-charged polyelectrolytes (PEs) have the advantage that they can self-crosslink electrostatically and those derived from marine organisms are an inexpensive alternative to glycosaminoglycans present in the extracellular matrix of human tissues. A range of different combinations of PEs and preparation conditions have been reported in the literature. However, although there has been some work on complex formation between chitosan (CS) and carrageenan (CRG), much of the work undertaken has ignored the effect of pH on the consequent physicochemical properties of self-crosslinked polyelectrolyte complex (PEC) gels, films and scaffolds. Chitosan is a positively-charged polysaccharide with NH3+ side groups derived from shrimp shells and, carrageenan is a negatively-charged polysaccharide with OSO3- side groups derived from red seaweed. These abundant polysaccharides possess advantageous properties such as biodegradability and low toxicity. However, at present, there is no clear consensus on the cell binding properties of CS and CRG or CS-CRG PEC materials. The aim of this study was to explore the properties of crosslinker-free PEC gels, solvent-cast PEC films and freeze-dried PEC scaffolds based on CS and CRG precursors for medical applications. The objective was to characterise the effect of pH of the production conditions on the physicochemical and biological properties of CS-CRG PECs. Experimental work focused on the interaction between PEs, the composition of PECs, the rheological properties of PEC gels and the mechanical properties of PEC films and scaffolds. In addition, cell and protein attachment to the PEC films was assessed to determine their interactions in a biological environment. For biomedical applications, these materials should ideally be stable when produced such that they can be processed to form either a film or a scaffold and have mechanical properties comparable to those of collagenous soft tissues. FTIR was used to confirm PEC formation. Zeta potential measurements indicated that the PECs produced at pH 2-6 had a high strength of electrostatic interaction with the highest occurring at pH 4-5. This resulted in stronger intra-crosslinking in the PEC gels which led to the formation of higher yield, solid content, viscosity and fibre content in PEC gels. The weaker interaction at pH 7-12 resulted in higher levels of CS incorporated into the complex and the formation of inter-crosslinking through entanglements between PEC units. This resulted in the production of strong and stiff PEC films and scaffolds appropriate for soft tissue implants. The PECs prepared at pH 7.4 and 9 also exhibited low swelling and mass loss, which was thought to be due to the high CS content and entanglements. From the range of samples tested, the PECs produced at pH 7.4 appeared to show the optimum combination of yield, stability and homogeneity for soft tissue implants. Biological studies were performed on CS, CRG and PECs prepared at pH 3, 5, 7.4 and 9. All of the PE and PEC films were found to be non-cytotoxic. When the response of three different cell types and a high binding affinity protein (tropoelastin) was evaluated; it was found that the CS-CRG PEC films displayed anti-adhesive properties. Based on these experimental observations and previous studies, a mechanistic model of the anti-adhesive behaviour of PEC surfaces was proposed. It was therefore concluded that the CS-CRG PECs produced might be suitable for non-biofouling applications.

碩士
明志科技大學
材料工程系碩士班
104
This research integrates transparent conductive film technology and hard coating technology, with the help of optical simulation to examine (1) high hardness and high transparent substrate, (2) high hardness and transparent conductive substrate, (3) high transmittance color substrate and (4) optical attenuator substrate. (1) Using transparent hard coating aluminum nitride as a protective layer, an anti-reflection design on the front of glass substrate is conducted. Then, at the back of the glass substrate, four anti-reflection layers are coated to promote penetration. Three kinds of high hardness and high transparency substrates were constructed. In Design A, the average transparency was 98.20% and the hardness was 9 GPa. In Design B, the average transparency was 97.28% and hardness was 14 GPa, twice that of the glass substrate. In Design C, the hardness was as high as 21 GPa, three times that of the glass substrate, with the average transparency of 93%. (2) ITO was added on the four layers of anti-reflection surface to render it conductive to electricity for the construction of high hardness and transparent substrate. (3) The four layers of anti-reflection layers were replaced with color ones to construct high hardness transparent color substrate for the application of color packaging of crystalline silicon solar cells. In addition to adding colors, it allows the crystalline silicon solar cell maintain its original efficiency. (4) Using black aluminum nitride and titanium nitride in their complementary conditions of visible light transmittance, it is able to design an attenuator substrate at 20%, 10%, 5%, and 1%. After adding color layers, a black color hard coating applicable on color sunglasses was designed.

碩士
大同大學
材料工程學系(所)
100
The anodized oxide film of magnesium alloy has many defects(poor bond strength, low wear and corrosion resistance, easy fading , uneven color, etc) in traditional surface coloring technology. These defects have largely limited the applications of magnesium alloy. In this paper, black ceramic film with uniform color, smooth surface, compact structure and excellent corrosion on AZ91D alloys was successfully obtained by micro-arc oxidation. Micro-arc oxidation (MAO) is a new electrochemical surface treatment technology, suitable for treating the aluminum, magnesium and titanium and other light metal alloys. In electrolyte by the arc discharge plasma generated of the substrate oxidation and high temperature melting, the film were formed with high hardness and corrosion resistance. In order to blacken the magnesium alloy AZ91D under plasma electrolytic oxidation (MAO) technology in silicate electrolyte containing copper sulfate and individual concentrations of K2FeO4, the characteristics of MAO coatings formed at different treatment time were investigated and dectection by XRD、 SEM 、XPSand color analysis instrument.

碩士
國防大學理工學院
化學工程碩士班
100
This study aims to technology develop a decorative and functional, and black trivalent chromium coating using electroplating. The black trivalent chromium coating has considerable in applicability solar thermal collector and optical apparatus. In this study, a galvanized iron sheet substrate was used as the substrate. The trivalent chromium ions were reduced on the substrate surface to from the black coating. The influence of current density, electroplating time, and the concentration of black addition agent on the properties of black film was investigated. Spectra scan colorimeter was employed to measure the black level. Scanning electron microscopy(SEM) with X-ray energy dispersive spectronmetry(EDS) was used to examine the surface morphology ans composition of the black film. The crystal structure of the film was obtained via X-ray diffraction. UV-Visible-Near IR spectrometer was used to measure the optical absorption, and electrochemical approach was used to analyze the corrosion behavior of the black trivalent Cr coating. The experimental results show that when a uniformly black trivalent chromium coating can be formed on the substrate when the current density was controlled at higher 30A/dm2 and electroplating for 1min. The black coating adheres well to the substrate. The black coating is mainly composed of CoP, Cr(OH)3、Cr2O3 and CrP Moreover, the black trivalent chromium coating produced at the corrent density over 30A/dm2, have better corrosion resistance than others.

碩士
國立虎尾科技大學
材料科學與綠色能源工程研究所
97
The metal-dielectric composite spectrally selective solar absorbers were widely used in solar thermal collectors due to its excellent absorption. The manufacture cost of the metal-dielectric composite spectrally selective solar absorbers is expensive and that limits its applications. In this work, the electroless composite coating technology which possesses lower cost, simple equipment and easy to operate characteristics was used to fabricate the Al2O3-black nickel composite solar selective surface on Al substrate and the Sol-gel technique was used to fabricated the anti-reflection (AR) layer. The effects of the particle size(300 nm ,70 nm , 15 nm) and content(4 g/L , 8 g/L , 16 g/L , 24 g/L , 28 g/L) of Al2O3, the thickness of the Al2O3-Black nickel composite coatings and the AR layers of SiO2 and TiO2 on the optical properties of the absorbers were investigated. The Uv/Vis/NIR spectrophotometer was utilized to measure the reflectance of the absorbers in the wavelength interval of 300 – 2500 nm, and the FTIR spectrometer was utilized to measure that in the wavelength interval of 2500 – 20000 nm. SEM and AFM were used to observe the surface morphologies and the thickness of coatings. The chemical structures of coatings were studied by ESCA. The environment durabilities including thermal stability and humidity resistance of the samples with optimized optical properties were performed.. The content of 300 nm alumina increases from 8 g/L to 28 g/L , the solar absorptance α of Al2O3-Black nickel/Al absorber increase from 0.69 to 0.79, the thermal emittance ε increase from 0.08 to 0.11. The content of 70 nm alumina increases from 8 g/L to 28 g/L , the solar absorptance α increase from 0.79 to 0.84, the thermal emittance ε increase from 0.13 to 0.20. The content of 15 nm alumina increases from 4 g/L to 16 g/L , the solar absorptance α increase from 0.81 to 0.86, the thermal emittance ε increase from 0.09 to 0.15. The 2.7 μm Al2O3-Black Nickel composite coatings contained 16 g/L of 15 nm alumina have optimum optic properties, solar absorptance α = 0.89 and low emittance ε = 0.07, and high selectivity factor 12.71. The solar absorptance and thermal emittance of the Al2O3-Black Nickel/Al absorbers with SiO2-0.5M AR layers are 0.92 and 0.09, respectively. Those of the Al2O3-Black Nickel/Al absorbers with TiO2 AR layers are 0.83 and 0.19, respectively. The selectivity factor of Al2O3-Black Nickel/Al absorbers after 300 ℃thermal stability test for 75 h decreased from 12.71 to 9.4, and that of black Nickel/Al absorbers decreased from 17 to 4.84. After 95 % humidity condensation test for 75 h, the selectivity factor of Al2O3 - Black Nickel/Al absorbers decreased from 12.71 to 4.81, and that of Black Nickel/Al absorbers decreased from 17 to 5.61.

碩士
元智大學
化學工程學系
92
After sterilization process or long term storage, fish and meat packaging food which contains biochemistry protein do easily cause black discoloration problem on interior packaging coating of can container. This research aims at solving the black discoloration problem by optimizing the resin formulation of epoxy, phenolic and amino resins, the selected resins must have a reliable supply source and meet the national health and food regulation. We evaluate different properties of the coating. This study provided an understanding to the formulations for real application. We expect this study will become the basic guidelines of high quality packaging coating for fish and meat food can container. This study will not only promote the quality of current packaging coating but also meet the critical requirements of the Safety & Hygiene regulation.

Koo Kai Ming = 具有黑色及灰色外貌的Ti-C, Ti-O和Ti-Zr-O裝飾硬膜之研究 / 古啓明.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2004.
Includes bibliographical references.
Text in English; abstracts in English and Chinese.
Koo Kai Ming = Ju you hei se ji hui se wai mao de Ti-C, Ti-O he Ti-Zr-O zhuang shi ying mo zhi yan jiu / Gu Qiming.
Acknowledgements --- p.I
Abstract --- p.II
論文摘要 --- p.IV
Table of Contents --- p.VI
List of Figures --- p.IX
List of Tables --- p.XIII
Chapter CHAPTER 1 --- Introduction --- p.1-1
Chapter 1.1 --- Overview and objectives --- p.1 -1
Chapter 1.2 --- Criteria for decorative coatings --- p.1 -2
Chapter 1.2.1 --- Color appearance --- p.1 -2
Chapter 1.2.2 --- Corrosion resistance --- p.1 -7
Chapter 1.2.3 --- Tribological properties --- p.1-7
Chapter 1.3 --- Coating techniques --- p.1 -8
Chapter 1.3.1 --- Plasma activated e-beam evaporation --- p.1 -8
Chapter 1.3.2 --- Cathodic arc deposition (CAD) --- p.1-10
Chapter 1.3.3 --- Closed field unbalanced magnetron sputtering (CFUBMS) --- p.1-10
Reference --- p.1-16
Chapter CHAPTER 2 --- Instrumentation --- p.2-1
Chapter 2.1 --- Film fabrication --- p.2-1
Chapter 2.1.1 --- Deposition system --- p.2-1
Chapter 2.1.2 --- Optical emission control in reactive sputtering --- p.2-3
Chapter 2.1.3 --- Asymmetric bipolar pulsed DC biasing --- p.2-5
Chapter 2.1.4 --- Two/Three axis rotation system --- p.2-5
Chapter 2.1.5 --- Substrate --- p.2-8
Chapter 2.1.6 --- Deposition procedure --- p.2-9
Chapter 2.2 --- Characterization --- p.2-10
Chapter 2.2.1 --- Thickness --- p.2-10
Chapter 2.2.2 --- Structural information --- p.2-11
Chapter 2.2.3 --- Chemical compositions and chemical state of the film elements --- p.2-11
Chapter 2.2.4 --- Amorphous carbon phase structure --- p.2-14
Chapter 2.2.5 --- Surface morphology --- p.2-14
Chapter 2.2.6 --- Reflection in the visible light range --- p.2-14
Chapter 2.2.7 --- Color impression --- p.2-15
Chapter 2.2.8 --- Film mechanical properties --- p.2-19
Chapter 2.2.9 --- Scratch resistance (Adhesion) measurement --- p.2-19
Reference --- p.2-21
Chapter CHAPTER3 E --- ngineering black decorative coatings with the Ti - C family by reactive ion plating --- p.3-1
Chapter 3.1 --- Introduction --- p.3-1
Chapter 3.2 --- Experiment --- p.3-2
Chapter 3.3 --- Results --- p.3-5
Chapter 3.3.1 --- Variations in color appearance --- p.3-5
Chapter 3.3.2 --- Nanoindentation hardness --- p.3-10
Chapter 3.3.3 --- Scratch resistance --- p.3-14
Chapter 3.3.4 --- Composition and microstructure --- p.3-17
Chapter 3.3.5 --- Amorphous carbon structure --- p.3-22
Chapter 3.4 --- Conclusions --- p.3-31
Reference
Chapter CHAPTER 4 --- Study on the colorimetric/optical properties of nonstoichiometric Ti - O thin films --- p.4-1
Chapter 4.1 --- Introduction --- p.4-1
Chapter 4.2 --- Experiment --- p.4-2
Chapter 4.3 --- Results and discussions --- p.4-4
Chapter 4.3.1 --- Variations in color appearance --- p.4-4
Chapter 4.3.2 --- Nanoindentation hardness --- p.4-9
Chapter 4.3.3 --- Composition and microstructure --- p.4-13
Chapter 4.4 --- Conclusions --- p.4-29
References --- p.4-30
Chapter CHAPTER 5 --- Doping the nonstoichiometric Ti - O coatings with zirconium --- p.5-1
Chapter 5.1 --- Introduction --- p.5-1
Chapter 5.2 --- Experiment --- p.5-1
Chapter 5.3 --- Results and discussions --- p.5-4
Chapter 5.3.1 --- Reflectivity and hardness --- p.5-4
Chapter 5.3.2 --- Composition and microstructure --- p.5-7
Chapter 5.4 --- "Comparison of the optical properties for Ti-C, Ti-O and Ti-Zr-0" --- p.5-14
Chapter 5.4.1 --- Black color --- p.5-14
Chapter 5.4.2 --- Grey color --- p.5-14
Chapter 5.5 --- Conclusions --- p.5-20
References
Chapter CHAPTER 6 --- Conclusion --- p.6-1
Chapter 6.1 --- Future works --- p.6-2

碩士
國立成功大學
機械工程學系碩博士班
101
This thesis develops a new type of three-dimensional (3D) photo-mask which can carry out sub-micrometer scaled patterning in a manner of UV beam-pen direct writing. The photo-mask fabricating method is based on silicon bulk machining, polymer replication, and most importantly, coating with a black–photoresist. Two applications have been experimentally demonstrated using the fabricated 3D photo-masks. One is for beam pen lithography (BPL) to generate complicated patterns in a mask-less manner, and the other one is to produce arrayed metallic patterns for obtaining localized surface plasmon resonance (LSPR) effects. The (3D) photo-mask along with a nano-positioning stage is applied to perform beam pen lithography. To fabricate the (3D) photo-mask, an h-PDMS mold with arrayed micro-pyramids is first replicated from a silicon mold which are prepared through standard photolithography and silicon bulk machining. The black-photoresist are then spin-coated on the h-PDMS mold. Relying on the pyramid-shaped microstructures and the coated black PR layer, it is possible to create an array of focused UV spots for UV exposure of PR layer. Experimental results show the feature size is around 400 nm, and metal micro-structures are obtained after a metal lift-off process. A BPL system is successfully constructed to produce different patterns at sub-micrometer scale, with the potential to fabricate complicate patterns in optoelectronic and semiconductor industry. For obtaining LSPR effect, a similar 3D photo-mask with pyramid-shaped cones and black-PR coated layer is fabricated but using the PUA materials. The 3D photo-mask contains hexagonally arrayed pyramid cones with a period of 1.2 μm. After photolithographic patterning and metallic lift-off, metallic nano-particles with a diameter of 400 nm disk and a diameter of 500 nm disk covering an area of 2 cm x 2 cm in size are obtained. For a gold array structures deployed on a glass substrate, a low transmittance spectrum near the wavelength of 1.6 μm and 1.7 μm due to LSPR effect is experimentally measured. The results are in good agreement with Finite element method (FEM). Based on this new method, optoelectronic devices can be designed and developed in the future.

碩士
國立中興大學
精密工程學系所
107
In this research, the effect of the microporous layer composition on the anion exchange membrane fuel cell performance has been systematically investigated. In particular, two types of commercial carbon materials, acetylene black and multi-walled carbon nanotubes (MWCNT), were used to fabricate the microporous layer with polytetrafluoroethylene (PTFE) content. Different weight ratios of acetylene to MWCNT ratios of acetylene to MWCNT have been prepared and coated on the gas diffusion substrate which made up carbon fiber paper with hydrophobic treatment. Furthermore, the better air permeability and lower in-plane electric resistance were obtained from the samples with more MWCNT addition, which are due to the higher mud crack density and dimension formed on the MPL and higher electrical conductivity of MWCNT, respectively. From the surface morphology analysis, the SEM results showed that the rougher MPL surface with more and larger mud cracks was observed on the samples with higher amount of MWCNT. This can be attributed to the agglomeration of carbon nanotubes in the MPL slurry. For single AEMFC testing, the results showed that the power densities of an H2/O2 AEMFC using GDLs with coated MPL prepared by various weight ratios of acetylene to MWCNT being 1:0, 4:1, 1:1, and 1:2 were 396, 411, 518, and 354 mW/cm2, respectively. This indicated that, among prepared MPL samples, the GDL with MPL containing the 1:1 ratio of acetylene to MWCNT exhibited the best cell performance which can be ascribed to the better air permeability and electric conductivity. However, higher MWCNT addition in the MPL compared to acetylene (1:2 ratio) will form too big mud cracks on the MPL surface, which impact on the water removal and catalyst layer coating, and thereby, significantly reduce the cell performance. Thus, although the MWCNT can be beneficial for both air permeability and electric conductivity of the GDL, due to the easy agglomeration of MWCNT, the amount of MWCNT in the MPL should be carefully optimized to achieve higher cell performance.

碩士
元智大學
機械工程學系
98
Micro-arc oxidation (MAO) is a new electrochemical surface treatment technology, suitable for treating the aluminum, magnesium and titanium and other light metal alloys. In electrolyte by the arc discharge plasma generated of the substrate oxidation and high temperature melting, the film were formed with high hardness and corrosion resistance. In order to blacken the magnesium alloy AZ91D under plasma electrolytic oxidation (MAO) technology in silicate electrolyte containing copper sulfate, the characteristics of MAO coatings formed at different treatment time were investigated and detection by XRD, EDS, FTIR and color analysis instrument (reflectance~2%). As the color of MgO coating is gray, so it can be deduced Cu2+ as the colorants of MAO blacken process.

Pigment manufacture in the twentieth and twenty-first centuries has largely been intended for industrial application. Consequently, the artist’s materials market which is by contrast very small and specialized, relies on pigments produced for the industrial market. Improvements to enhance performance in an industrial context, has led to the introduction of a variety of different surface treatments applied to pigment particles. Pigment coatings can consist of one or more thin layers of either organic or inorganic material, or a combination of both. Their nature and their presence in very small amounts present a challenge for the detection and identification of these compounds. Part I of this thesis explores the literature covering pigment coating materials, application methods and the terminology used to identify the range and types of materials in use. Part II explores the analytical strategies that can be employed to detect these treatments on pigment samples. The pigments selected for this research include: Umber and Vine Black purchased from Kremer Pigmente during the Carlyle MOLART Fellowship for the creation of “historically accurate” paint reconstructions; Ultramarine Blue pigments since the use of coatings on these pigments is reported in the literature (for greater acid resistance); Cu-Phthalocyanine Blue pigments as these are currently amongst the most popular blue pigments; and the Hansa yellows, PY3 and PY74 from the manufacturer Royal Talens to determine the possible presence of a surface treatment or coating which could be responsible for paint instability. Analytical methods employed for this thesis work to characterize the organic fraction on pigments surfaces included: Evolved Gas Analysis Mass spectrometry (EGA/MS); Pyrolysis Gas Chromatography Mass Spectrometry (Py-GC/MS); Py-GC/MS using thermally assisted hydrolysis and methylation (THM) with gas chromatography-mass spectrometry (GC/MS) in combination with ultrafast thermal desorption (UTD), meaning the samples were investigated through “slow pyrolysis” and not as flash pyrolysis. This method, developed at RCE, involves a temperature program that enables a one-shot analysis with evaporation before pyrolysis. To characterize inorganic materials, the following instruments were used: Scanning Electron Microscope Energy Dispersive X-ray (SEM-EDX); (Scanning) Transmission Electron Microscope Energy Dispersive X-ray ((S) TEM-EDX); and Field Emission Gun Scanning Electron Microscope (FEG-SEM). Surface treatments influence the physical properties of pigments during the manufacture of coatings, including oil paints. By understanding their applications and chemistry and determining methods for identifying them in situ on pigment particles, their influence on the long-term stability within modern artist’s oil paint can be assessed.