Sample records for film metal coated

  1. Formation of selenide, sulfide or mixed selenide-sulfide films on metal or metal coated substrates

    DOEpatents

    Eser, Erten; Fields, Shannon

    2012-05-01

    A process and composition for preventing cracking in composite structures comprising a metal coated substrate and a selenide, sulfide or mixed selenide sulfide film. Specifically, cracking is prevented in the coating of molybdenum coated substrates upon which a copper, indium-gallium diselenide (CIGS) film is deposited. Cracking is inhibited by adding a Se passivating amount of oxygen to the Mo and limiting the amount of Se deposited on the Mo coating.

  2. Polystyrene film-coated glassware: a new means of reducing metal losses in trace metal speciation

    Microsoft Academic Search

    José Paulo Pinheiro; Wouter Bosker

    2004-01-01

    A recently developed process for coating a glass surface with polystyrene (PS) film, by use of a simple chemical process has been used to reduce trace metal adsorption by cell components. The glass coating is a two-step procedure consisting of covalent attachment of vinyl-terminated PS to Si atoms on the glass surface then adsorption of PS from solution to create

  3. Thin film metal coated fiber optic hydrophone probe.

    PubMed

    Gopinath Minasamudram, Rupa; Arora, Piyush; Gandhi, Gaurav; Daryoush, Afshin S; El-Sherif, Mahmoud A; Lewin, Peter A

    2009-11-01

    Our purpose is to improve the performance sensitivity of a fiber sensor used as a fiber optic hydrophone probe (FOHP) by the addition of nanoscale thin film gold coating. The fiber is designed to provide a uniform and spatial averaging free response up to 100 MHz by etching down to an active diameter of approximately 9 mum. The performance sensitivity of straight cleaved (i.e., full size core and cladding) uncoated, tapered uncoated, and tapered thin film gold-coated fiber sensors was compared in the frequency range from 1.5 to 20 MHz in the presence of acoustic amplitude pressure levels as high as 6 MPa. An unprecedented voltage sensitivity of -245 dB relative to 1 V/muPa (560 mV/MPa) was measured for a thin film gold-coated FOHP by optimizing the gold coating thickness. PMID:19881652

  4. Thin Film Metal Coated Fiber Optic Hydrophone Probe

    PubMed Central

    Gopinath, R.; Arora, P.; Gandhi, G.; Daryoush, A.S.; El-Sherif, M.; Lewin, P.A.

    2010-01-01

    The purpose of this work was to improve on sensitivity performance of fiber sensor employed as Fiber Optic Hydrophone Probe (FOHP) by nano-scale thin film gold coating. The fiber is designed to provide a uniform and spatial averaging free response up to 100 MHz by etching down to an active diameter of about 9 ?m. The sensitivity performance of straight cleaved (i.e. full size core and cladding) uncoated, tapered uncoated and tapered thin film gold coated fiber sensors were compared in the frequency range of 1.5 MHz to 20 MHz in the presence of acoustic pressure amplitude levels of up to 6 MPa. An unprecedented voltage sensitivity of ?245 dB re 1V/uPa (560 mV/ MPa) was measured for thin film gold coated FOHP by optimizing the gold coating thickness. PMID:19881652

  5. Adhesion of metals to spin-coated fluorocarbon polymer films

    NASA Astrophysics Data System (ADS)

    Kim, Yong-Kil; Chang, Chin-An; Schrott, A. G.

    1990-01-01

    Adhesion between metals and fluorocarbon polymer films has been studied for Cu, Cr, Ti, Al, and Au on polytetrafluoroethylene (PTFE) and tetrafluoroethylene-hexafluoropropylene copolymer (FEP) films. Polymer films were applied on the Cr/SiO2 /Si substrate by spinning the aqueous dispersions of the polymer resin particles, followed by thermal curing. Strips of different metals were deposited on the polymers, and adhesion was measured at 90° peel test. The peel strengths were invariably higher for the metals on FEP than those of the corresponding metals on PTFE. Among the metals, Ti showed the highest peel strength for both polymers, followed by Cr and Al, with Cu and Au being the lowest. The peel strengths of Ti, Cr, and Cu on FEP are 85, 45, and 12 g/mm, respectively, and the corresponding ones on PTFE are 23, 5, and 2 g/mm, respectively. X-ray photoelectron spectroscopic analysis shows that the metal-polymer bonding involves the metal-carbon interactions. The strongest interaction is observed for Ti with the polymers, forming Ti carbidelike bonds. Cr also shows strong interaction with the two polymers, but to a lesser degree compared with Ti. Only a weak bonding is shown for Cu. The difference in peel strengths among the metals shows a correlation with the difference in electronegativities between the metals and carbon. Little contribution to the observed peel strengths is seen from the surface morphological analysis of the untreated polymers.

  6. Diamond Composite Films for Protective Coatings on Metals and Method of Formation

    NASA Technical Reports Server (NTRS)

    Ong, Tiong P. (Inventor); Shing, Yuh-Han (Inventor)

    1997-01-01

    Composite films consisting of diamond crystallites and hard amorphous films such as diamond-like carbon, titanium nitride, and titanium oxide are provided as protective coatings for metal substrates against extremely harsh environments. A composite layer having diamond crystallites and a hard amorphous film is affixed to a metal substrate via an interlayer including a bottom metal silicide film and a top silicon carbide film. The interlayer is formed either by depositing metal silicide and silicon carbide directly onto the metal substrate, or by first depositing an amorphous silicon film, then allowing top and bottom portions of the amorphous silicon to react during deposition of the diamond crystallites, to yield the desired interlayer structure.

  7. Localization of folds and cracks in thin metal films coated on flexible elastomer foams.

    PubMed

    Vandeparre, Hugues; Liu, Qihan; Minev, Ivan R; Suo, Zhigang; Lacour, Stéphanie P

    2013-06-11

    Thin metal films coated on soft elastomeric foam substrates exhibit enhanced electromechanical performance. The open-cell foam structure conveys highly anisotropic mechanical properties within the top, thin capping elastomer at the surface of the foam. Upon stretching, large strain fields inducing cracks and folds localize above the foam cells, while the surrounding cell ligaments remain almost strain-free, enabling stable electrical conduction in the metallic coating. PMID:23629920

  8. Metal Coatings

    NASA Technical Reports Server (NTRS)

    1994-01-01

    During the Apollo Program, General Magnaplate Corporation developed process techniques for bonding dry lubricant coatings to space metals. The coatings were not susceptible to outgassing and offered enhanced surface hardness and superior resistance to corrosion and wear. This development was necessary because conventional lubrication processes were inadequate for lightweight materials used in Apollo components. General Magnaplate built on the original technology and became a leader in development of high performance metallurgical surface enhancement coatings - "synergistic" coatings, - which are used in applications from pizza making to laser manufacture. Each of the coatings is designed to protect a specific metal or group of metals to solve problems encountered under operating conditions.

  9. Ceramic coating effect on liner metal temperatures of film-cooled annular combustor

    NASA Technical Reports Server (NTRS)

    Claus, R. W.; Wear, J. D.; Liebert, C. H.

    1979-01-01

    An experimental and analytical investigation was conducted to determine the effect of a ceramic coating on the average metal temperatures of full annular, film cooled combustion chamber liner. The investigation was conducted at pressures from 0.50 to 0.062. At all test conditions, experimental results indicate that application of a ceramic coating will result in significantly lower wall temperatures. In a simplified heat transfer analysis, agreement between experimental and calculated liner temperatures was achieved. Simulated spalling of a small portion of the ceramic coating resulted in only small increases in liner temperature because of the thermal conduction of heat from the hotter, uncoated liner metal.

  10. Transfer printing of patterned metal films using parylene C coated surfaces J. Bavier a,b

    E-print Network

    Rubloff, Gary W.

    Transfer printing of patterned metal films using parylene C coated surfaces J. Bavier a,b , J October 2012 Available online 24 November 2012 Keywords: Transfer printing Flexible electronics Surface treatments a b s t r a c t Successful transfer printing of aluminum (Al), copper (Cu), silver (Ag), nickel

  11. Microfeature edge quality enhancement in excimer laser micromachining of metal films by coating with a sacrificial polymer layer

    NASA Astrophysics Data System (ADS)

    Nadeem Akhtar, Syed; Sharma, Shashank; Dayal, Govind; Ramakrishna, S. Anantha; Ramkumar, J.

    2015-06-01

    A novel technique for enhanced excimer laser micromachining of metallic thin films by first coating the metal film with a thin polymer film is presented. The sacrificial polymer film acts as a protective and a clamping layer, preventing the metal film from undergoing cracking and damage during the laser ablation. The machined patterns are characterized regarding their quality in terms of edge roughness, lateral overcut and boundary integrity in proximity machining. Significant improvement in these aspects is observed when the machining is carried out on metal films coated with thin polymer films. Details of the effects of the fluence and spot overlap on the micromachined patterns are investigated. The technique allows sharp machining of micropatterns on thin metal films, over length scales ranging from hundreds of micrometers down to a single micrometer, thereby proving to be the only technique that can be used to laser micromachine thin films at the length scale of a single micrometer. This technique is expected to be useful for large scale patterning of metallic films, particularly for plasmonic applications and infrared/terahertz metamaterials.

  12. Characteristics of surface photorefractive waves in a nonlinear SBN-75 crystal coated with a metal film

    SciTech Connect

    Nurligareev, D Kh; Usievich, B A; Sychugov, V A; Ivleva, Lyudmila I [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

    2013-01-31

    Based on the calculation of the electrostatic field potential of space charges, we have analysed the characteristic features of light-induced scattering of extraordinary polarised light in photorefractive (PR) crystals (for example, an SBN-75 crystal). Using the method of images, the electrostatic field is analysed for surface (aperiodic) waves along the crystal - dielectric (air) interface. It is shown that the field distributions satisfying the boundary conditions can emerge only upon accumulation of a screening electric charge in a narrow transition layer of thickness {approx}1 mm, the sign of the charge being opposite that of the space charge in the illuminated region of the crystal. A model is proposed to explain the observed features of the surface PR waves in a metal-film coated PR crystal. In considering the contact potential difference at the PR crystal - film interface it is shown that in the crystal layer (adjacent to the film) enriched with charge carriers, i.e., electrons, the refractive index can be significantly reduced. In the case of small excitation angles (0 - 1.5deg ), this layer can act as an optical barrier, the reflection from which can result in near-surface waves; a characteristic difference from the previously observed oscillatory surface waves is the presence of a broadened intensity distribution shifted inside the crystal. (nonlinear optical phenomena)

  13. Analysis of metal temperature and coolant flow with a thermal-barrier coating on a full-coverage-film-cooled turbine vane

    NASA Technical Reports Server (NTRS)

    Meitner, P. L.

    1978-01-01

    The potential benefits of combining full-coverage film cooling with a thermal-barrier coating were investigated analytically for sections on the suction and pressure sides a high-temperature, high-pressure turbine vane. Metal and ceramic coating temperatures were calculated as a function of coating thickness and coolant flow. With a thermal-barrier coating, the coolant flows required for the chosen sections were half those of an uncoated design, and the metal outer temperatures were simultaneously reduced by over 111 K (200 F). For comparison, transpiration cooling was also investigated. Full-coverage film cooling of a coated vane required more coolant flow than did transpiration cooling.

  14. Structural characterization of multi-coated YBCO films processed by metal-organic deposition method

    NASA Astrophysics Data System (ADS)

    Jang, S. H.; Lim, J. H.; Lee, S. Y.; Kim, K. T.; Lee, C. M.; Park, E. C.; Hwang, S. M.; Park, S.; Joo, J.

    2008-09-01

    YBCO films were fabricated using the TFA-MOD process. The effects of film thickness on phase formation, degree of texture, microstructures, and critical properties were evaluated by X-ray diffraction, pole-figure, and transmission electron microscopy. The films were prepared with various thicknesses by producing multi-coated films by repeating the dip-coating and calcining processes. The microstructure and resultant critical current ( Ic) and critical current density ( Jc) varied remarkably with film thickness: the Ic increased from 39 to 169 A/cm-width, while Jc ranged from 0.85 to 0.92 MA/cm 2 with increasing number of coatings from one to three or four. Both values decreased when further coatings were applied as a result of microstructural degradation. It is believed that this decrease in Ic for the multi-coated film is partly due to the presence of a second phase, pores, and poor texture formability. The optimum thickness for maximizing both the Ic and Jc values is believed to be in the range of 1.1-1.7 ?m.

  15. Coating of plasma polymerized film

    NASA Technical Reports Server (NTRS)

    Morita, S.; Ishibashi, S.

    1980-01-01

    Plasma polymerized thin film coating and the use of other coatings is suggested for passivation film, thin film used for conducting light, and solid body lubrication film of dielectrics of ultra insulators for electrical conduction, electron accessories, etc. The special features of flow discharge development and the polymerized film growth mechanism are discussed.

  16. Photovoltage and stability of an n-type silicon semiconductor coated with metal or metal-free phthalocyanine thin films in aqueous redox solutions

    SciTech Connect

    Nakato, Y.; Shioji, M.; Tsubomura, H.

    1981-06-11

    An n-type silicon (n-Si) semiconductor coated with an evaporated thin film of metal phthalocyanine (MPc) or metal-free phthalocyanine (H/sub 2/Pc) worked as a fairly stable photoanode in aqueous redox solutions. The photovoltage observed for a photocell, (n-Si/CuPc/Fe/sup 3 +//Fe/sup 2 +/ aqueous solution (pH 4.2) /Pt), was 0.50 V, only slightly less than that for a p-n junction Si photocell (approx. 0.6 V). The action spectrum was similar to that of a bare n-Si electrode, except for a depression caused by photoabsorption by the CuPc film in the red region. The above wet photocell has current-voltage characteristics better than those for a solid photocell, (n-Si/CuPc/Pd).

  17. Spin-coated PMMA films

    Microsoft Academic Search

    N. G. Semaltianos

    2007-01-01

    Polymethylmethacrylate (PMMA) spin-coated thin films are commonly used as resist films in micro\\/nanofabrication processes. By using atomic force microscopy (AFM) imaging, scratching lithography and force–distance curves spectroscopy, the spin coating and post-processing conditions were determined, for obtaining films whose surface morphology appears featureless or is dominated by pinholes and other surface defects. Featureless appear the surfaces of films spin coated

  18. Effect of thin condensate films of a metal working fluid of an electric propulsion engine on the integral optical coefficients of a spacecraft's thermal control coating

    NASA Astrophysics Data System (ADS)

    Chirov, A. A.

    2014-05-01

    Materials on experimental studies to determine the effect of thin condensate films of cesium (used as a model working medium for electric propulsion engines and some spacecraft power sources) on integral optical coefficients of spacecraft thermal control coatings are presented. A technique modified by the author and employing the regular thermal regime of a thin metal plate is used. Measurement results demonstrate that films with thicknesses of 100-1000 Å can seriously degrade the integral optical coefficients of thermal control coatings and thus disturb the heat balance of some spacecraft systems.

  19. Mixed polyelectrolyte coatings on glassy carbon electrodes: Ion-exchange, permselectivity properties and analytical application of poly- l-lysine–poly(sodium 4-styrenesulfonate)-coated mercury film electrodes for the detection of trace metals

    Microsoft Academic Search

    Sandra C. C. Monterroso; Helena M. Carapuça; Armando C. Duarte

    2006-01-01

    The present work describes the preparation, optimization and characterization of mixed polyelectrolyte coatings of poly-l-lysine (PLL) and poly(sodium 4-styrenesulfonate) (PSS) for the modification of thin mercury film electrodes (MFEs). The novel-modified electrodes were applied in the direct analysis of trace metals in estuarine waters by square-wave anodic stripping voltammetry (SWASV). The effects of the coating morphology and thickness and also

  20. Carbonaceous film coating

    SciTech Connect

    Maya, L.

    1989-05-23

    This patent describes a method of making a carbonaceous film. It comprises heating tris(1,3,2-benzodiazaborolo)borazine or dodecahydro tris(1,3,2)diazaborine(1,2-a:1'2'-c:1 2 -e)borazine in an inert atmosphere in the presence of a substrate to a temperature at which the borazine compound decomposes. The decomposition products deposit onto the substrate to form a thin, tenacious, highly reflective conductive coating having a narrow band gap which is susceptible of modification and a relatively low coefficient of friction.

  1. Thin film ion conducting coating

    DOEpatents

    Goldner, Ronald B. (Lexington, MA); Haas, Terry (Sudbury, MA); Wong, Kwok-Keung (Watertown, MA); Seward, George (Arlington, MA)

    1989-01-01

    Durable thin film ion conducting coatings are formed on a transparent glass substrate by the controlled deposition of the mixed oxides of lithium:tantalum or lithium:niobium. The coatings provide durable ion transport sources for thin film solid state storage batteries and electrochromic energy conservation devices.

  2. Scribable coating for plastic films

    NASA Technical Reports Server (NTRS)

    Clark, R. T.

    1967-01-01

    Scribable opaque coating for transparent plastic film tape is not affected by aging, vacuum, and moderate temperature extremes. It consists of titanium dioxide, a water-compatible acrylic polymer emulsion, and a detergent. The coating mixture is readily dispersed in water before it is dried.

  3. Mixed polyelectrolyte coatings on glassy carbon electrodes: Ion-exchange, permselectivity properties and analytical application of poly-l-lysine-poly(sodium 4-styrenesulfonate)-coated mercury film electrodes for the detection of trace metals.

    PubMed

    Monterroso, Sandra C C; Carapuça, Helena M; Duarte, Armando C

    2006-02-28

    The present work describes the preparation, optimization and characterization of mixed polyelectrolyte coatings of poly-l-lysine (PLL) and poly(sodium 4-styrenesulfonate) (PSS) for the modification of thin mercury film electrodes (MFEs). The novel-modified electrodes were applied in the direct analysis of trace metals in estuarine waters by square-wave anodic stripping voltammetry (SWASV). The effects of the coating morphology and thickness and also of the monomeric molar ratio PLL/PSS on the cation-exchange ability of the PLL-PSS polyelectrolyte coatings onto glassy carbon (GC) were evaluated using target cationic species such as dopamine (DA) or lead cation. Further, the semi-permeability of the PLL-PSS-coated electrodes based both on electrostatic interactions and on molecular size leads to an improved anti-fouling ability against several tensioactive species. The analytical usefulness of the PLL-PSS-mixed polyelectrolyte coatings on thin mercury film electrodes is demonstrated via SWASV measurements of trace metals (lead, copper and cadmium at the low nanomolar level; accumulation time of 180s) in estuarine waters containing moderate levels of dissolved organic matter, resulting in a fast and direct methodology requiring no sample pretreatment. PMID:18970511

  4. Polymer-assisted aqueous deposition of metal oxide films

    DOEpatents

    Li, DeQuan (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM)

    2003-07-08

    An organic solvent-free process for deposition of metal oxide thin films is presented. The process includes aqueous solutions of necessary metal precursors and an aqueous solution of a water-soluble polymer. After a coating operation, the resultant coating is fired at high temperatures to yield optical quality metal oxide thin films.

  5. Thermal Properties of Metal-Coated Vertically-Aligned Single Wall Nanotube Films M. Panzer, G. Zhang, D. Mann, X. Hu, E. Pop, H. Dai, and K. E. Goodson

    E-print Network

    Zhang, Guangyu

    Thermal Properties of Metal-Coated Vertically-Aligned Single Wall Nanotube Films M. Panzer, G properties, there are little data for aligned films of single wall nanotubes. This paper measures the thermal properties including their interface resistances. The data show the total thermal resistance of the TIM is R

  6. Barrier Coatings for Refractory Metals and Superalloys

    SciTech Connect

    SM Sabol; BT Randall; JD Edington; CJ Larkin; BJ Close

    2006-02-23

    In the closed working fluid loop of the proposed Prometheus space nuclear power plant (SNPP), there is the potential for reaction of core and plant structural materials with gas phase impurities and gas phase transport of interstitial elements between superalloy and refractory metal alloy components during service. Primary concerns are surface oxidation, interstitial embrittlement of refractory metals and decarburization of superalloys. In parallel with kinetic investigations, this letter evaluates the ability of potential coatings to prevent or impede communication between reactor and plant components. Key coating requirements are identified and current technology coating materials are reviewed relative to these requirements. Candidate coatings are identified for future evaluation based on current knowledge of design parameters and anticipated environment. Coatings were identified for superalloys and refractory metals to provide diffusion barriers to interstitial transport and act as reactive barriers to potential oxidation. Due to their high stability at low oxygen potential, alumina formers are most promising for oxidation protection given the anticipated coolant gas chemistry. A sublayer of iridium is recommended to provide inherent diffusion resistance to interstitials. Based on specific base metal selection, a thin film substrate--coating interdiffusion barrier layer may be necessary to meet mission life.

  7. Tailoring Thin Film-Lacquer Coatings for Space Application

    NASA Technical Reports Server (NTRS)

    Peters, Wanda C.; Harris, George; Miller, Grace; Petro, John

    1998-01-01

    Thin film coatings have the capability of obtaining a wide range of thermal radiative properties, but the development of thin film coatings can sometimes be difficult and costly when trying to achieve highly specular surfaces. Given any space mission's thermal control requirements, there is often a need for a variation of solar absorptance (Alpha(s)), emittance (epsilon) and/or highly specular surfaces. The utilization of thin film coatings is one process of choice for meeting challenging thermal control requirements because of its ability to provide a wide variety of Alpha(s)/epsilon ratios. Thin film coatings' radiative properties can be tailored to meet specific thermal control requirements through the use of different metals and the variation of dielectric layer thickness. Surface coatings can be spectrally selective to enhance radiative coupling and decoupling. The application of lacquer to a surface can also provide suitable specularity for thin film application without the cost and difficulty associated with polishing.

  8. Development of a novel method to measure the film thickness of cured can coatings

    Microsoft Academic Search

    Janine Wagner; Thomas Moschakis; Phillip V. Nelson; Bronislaw L. Wedzicha

    2011-01-01

    A new technique was developed for measuring the thickness of can coatings applied to a metal substrate. A metal disc with a known radius creates a small indent in the coating, stopping exactly when the coating thickness is cut through. The indent length is employed to calculate the coating thickness. Accurate measurement of thin films is achieved as the indent

  9. Cellulose acetate coated mercury film electrodes for anodic stripping voltametry

    Microsoft Academic Search

    Joseph. Wang; Lori D. Hutchins-Kumar

    1986-01-01

    The response characteristics and analytical advantages of cellulose acetate coated mercury film electrodes for anodic stripping measurements of trace metals are described. The coating provides an effective barrier of the mercury surface, thus eliminating the effects of various organic surfactants. For example, up to at least 100 ppm gelatin does not alter the response. The diagnostic power of rotating disk

  10. Metal-Coated Optical Fibers for High Temperature Applications

    NASA Technical Reports Server (NTRS)

    Zeakes, Jason; Murphy, Kent; Claus, Richard; Greene, Jonathan; Tran, Tuan

    1996-01-01

    This poster will highlight on-going research at the Virginia Tech Fiber & Electro-Optics Research Center (FEORC) in the area of thin films on optical fibers. Topics will include the sputter deposition of metals and metal; alloys onto optical fiber and fiber optic sensors for innovative applications. Specific information will be available on thin film fiber optic hydrogen sensors, corrosion sensors, and metal-coated optical fiber for high temperature aerospace applications.

  11. Peel testing metalized films

    NASA Technical Reports Server (NTRS)

    Bivins, L.; Smith, T.

    1980-01-01

    Flimsy ultrathin sheets are mounted on glass for peel-strength measurements. Technique makes it easier to perform peel tests on metalized plastic films. Technique was developed for determining peel strength of thin (1,000 A) layers of aluminum on Kapton film. Previously, material has been difficult to test because it is flimsy and tends to curl up and blow away at slightest disturbance. Procedure can be used to measure effects on metalization bond strength of handling, humidity, sunlight, and heat.

  12. Milk Proteins for Edible Films and Coatings

    Microsoft Academic Search

    KHAOULA KHWALDIA; CRISTINA PEREZ; SYLVIE BANON; STÉPHANE DESOBRY; JOËL HARDY

    2004-01-01

    Due to the recent increase in ecological consciousness, research has turned toward finding edible materials. Viable edible films and coatings have been produced using milk proteins. These films and coatings may retard moisture loss, are good oxygen barriers, show good tensile strength and moderate elongation, are flexible, and generally have no flavor or taste. Incorporation of lipids in protein films,

  13. Mechanical study of metallized polyethylene terephthalate (PET) films

    Microsoft Academic Search

    Sandhya Gupta; Manasvi Dixit; Kananbala Sharma; N. S. Saxena

    2009-01-01

    Mechanical properties such as Young's modulus (Y), storage modulus (E?), glass transition temperature (Tg), tensile strength (?), and yield strength (?y) of metallized polyethylene terephthalate (PET) films have been measured using Dynamic Mechanical Analyser (DMA). Commercially available PET film thickness of 20?m has been used for metallization. Aluminium (Al) and lead (Pb) have been coated separately on PET films by

  14. Method of coating metal surfaces to form protective metal coating thereon

    DOEpatents

    Krikorian, O.H.; Curtis, P.G.

    1992-03-31

    A process is disclosed for forming a protective metal coating on a metal surface using a flux consisting of an alkali metal fluoride, an alkaline earth metal fluoride, an alkali metal fluoaluminate, an alkali metal fluosilicate, and mixtures thereof. The flux, in particulate form, is mixed with particles of a metal coating material which may comprise aluminum, chromium, mixtures thereof, and alloys containing at least 50 wt. % aluminum and the particulate mixture is applied to the metal surface in a single step, followed by heating the coated metal surface to a temperature sufficient to cause the metal coating material to react with the metal surface to form a protective reaction product in the form of a metal coating bonded to the metal surface. The metal surface which reacts with the metal coating material to form the protective coating may comprise Fe, Co, Ni, Ti, V, Cr, Mn, Zr, Nb, Mo, Tc, Hf, Ta, W, Re and alloys thereof. 1 figure.

  15. Method of coating metal surfaces to form protective metal coating thereon

    DOEpatents

    Krikorian, Oscar H. (Danville, CA); Curtis, Paul G. (Tracy, CA)

    1992-01-01

    A process is disclosed for forming a protective metal coating on a metal surface using a flux consisting of an alkali metal fluoride, an alkaline earth metal fluoride, an alkali metal fluoaluminate, an alkali metal fluosilicate, and mixtures thereof. The flux, in particulate form, is mixed with particles of a metal coating material which may comprise aluminum, chromium, mixtures thereof, and alloys containing at least 50 wt. % aluminum and the particulate mixture is applied to the metal surface in a single step, followed by heating the coated metal surface to a temperature sufficient to cause the metal coating material to react with the metal surface to form a protective reaction product in the form of a metal coating bonded to the metal surface. The metal surface which reacts with the metal coating material to form the protective coating may comprise Fe, Co, Ni, Ti, V, Cr, Mn, Zr, Nb, Mo, Tc, Hf, Ta, W, Re and alloys thereof.

  16. Coated Metal Articles and Method of Making

    DOEpatents

    Boller, Ernest R.; Eubank, Lowell D.

    2004-07-06

    The method of protectively coating metallic uranium which comprises dipping the metallic uranium in a molten alloy comprising about 20-75% of copper and about 80-25% of tin, dipping the coated uranium promptly into molten tin, withdrawing it from the molten tin and removing excess molten metal, thereupon dipping it into a molten metal bath comprising aluminum until it is coated with this metal, then promptly withdrawing it from the bath.

  17. Coated metal articles and method of making

    DOEpatents

    Boller, Ernest R. (Van Buren Township, IN); Eubank, Lowell D. (Wilmington, DE)

    2004-07-06

    The method of protectively coating metallic uranium which comprises dipping the metallic uranium in a molten alloy comprising about 20-75% of copper and about 80-25% of tin, dipping the coated uranium promptly into molten tin, withdrawing it from the molten tin and removing excess molten metal, thereupon dipping it into a molten metal bath comprising aluminum until it is coated with this metal, then promptly withdrawing it from the bath.

  18. A Nafion-coated bismuth film electrode for the determination of heavy metals in vegetable using differential pulse anodic stripping voltammetry: An alternative to mercury-based electrodes.

    PubMed

    Xu, He; Zeng, Liping; Huang, Dekun; Xian, Yuezhong; Jin, Litong

    2008-08-15

    Mercury electrodes have been traditionally employed for achieving high reproducibility and sensitivity of the stripping technique. However, new alternative electrode materials are highly desired because of the toxicity of mercury. Bismuth is an electrode material characterized by its low toxicity and its ability to form alloys with some metals such as cadmium, lead and zinc, allowing their preconcentration at the electrode surface. In this work, we reported the simultaneous determination of Pb(II), Cd(II) and Zn(II) at the low ?g/l concentration levels by differential pulse anodic stripping voltammetry (DPASV) on a Nafion-coated bismuth film electrode (NCBFE) plated in situ, and investigated the application of NCBFE to heavy metals analysis in vegetable samples. The analytical performance of NCBFE was evaluated for simultaneous determination of Pb(II), Cd(II) and Zn(II) in non-deaerated solution, with the limits of determination of 0.30?g/l for Zn, 0.17?g/l for Cd and Pb at a preconcentration time of 180s. High reproducibility for NCBFE was indicated from the relative standard deviations of 2.4% for Pb, 2.0% for Cd and 3.4% for Zn at the 15?g/l level (n=15). The NCBFE was successfully applied to determine Pb and Cd in vegetable samples, and the results were in agreement with those of graphite furnace atomic absorption spectrometry (GFAAS). PMID:26049998

  19. Adhesion properties and wetting by molten metals of thin metallic films applied to nonmetallic materials

    Microsoft Academic Search

    Yu. V. Naidich; B. D. Kostyuk; G. A. Kolesnichenko; S. S. Shaikevich

    1973-01-01

    reaction of thin Mo films applied to various nonmetallic materials, namely, A1203 (sapphire), SiO 2 (vitreous quartz), and graphite, and also on the wetting of these metal-coated materials by a molten metal (copper). The subject selected is of considerable practical importance from the point of view of determination of the optimum coating thickness, as comparatively thick metallic films as a

  20. Corrosion protective coating for metallic materials

    DOEpatents

    Buchheit, Rudolph G. (Albuquerque, NM); Martinez, Michael A. (Albuquerque, NM)

    1998-01-01

    Corrosion protective coatings for metallic materials, particularly aluminum and aluminum alloys, produced with simple, low-cost equipment and materials other than toxic metals or metal salts, or metal cyanides. The metallic material is cleaned, degreased, and deoxidized, the surface is converted to a substantially alkaline condition, and the surface is chemically sealed with inorganic metal compounds.

  1. Corrosion protective coating for metallic materials

    DOEpatents

    Buchheit, R.G.; Martinez, M.A.

    1998-05-26

    Corrosion protective coatings for metallic materials, particularly aluminum and aluminum alloys, produced with simple, low-cost equipment and materials other than toxic metals or metal salts, or metal cyanides is disclosed. The metallic material is cleaned, degreased, and deoxidized, the surface is converted to a substantially alkaline condition, and the surface is chemically sealed with inorganic metal compounds. 1 fig.

  2. Corrosion control of metals by organic coatings

    SciTech Connect

    Ooij, W.J. van; Bierwagen, G.P.; Skerry, B.S.; Mills, D.

    1999-01-01

    The authors present a comprehensive treatment of the entire field of corrosion control of metals, from mechanisms and testing procedures to modification of metal surfaces and interfaces by silanes and plasma techniques. They discuss the new, sophisticated analytical tools, such as Time-of-Flight SIMS and electrochemical impedance spectroscopy, and all materials -- metals, pretreatments, and paint systems. The contents include: (1) Corrosion under organic coatings; (2) Mechanisms of corrosion control by organic coatings; (3) Metal pretreatments; (4) Techniques to study organic coating-metal interfaces; (5) Modification of metal surfaces and interfaces; (6) corrosion testing; (7) Adhesion testing; (8) Paint systems; (9) Conclusions and prospects references.

  3. Stable aqueous film coating dispersion of zein

    Microsoft Academic Search

    H. X. Guo; J. Heinämäki; J. Yliruusi

    2008-01-01

    The effects of plasticizers, pH, and electrolytes on film formation and physical stability of aqueous film coating dispersions (pseudolatexes) of zein were evaluated. The influence of plasticizer on film formation mechanism and minimum film-formation temperature (MFT) were monitored by means of hot stage microscopy (HSM). Furthermore, the effects of pH and electrolytes on the short-term physical stability of pseudolatexes were

  4. Improved performance of thin film broadband antireflective coatings

    NASA Astrophysics Data System (ADS)

    Mishrikey, Matthew; Fallahi, Arya; Hafner, Christian; Vahldieck, Rüdiger

    2007-10-01

    Antireflective coatings are useful for a range of applications, from minimizing the radar cross-section of stealth aircraft, to maximizing the efficiency of solar energy panels. New low-index nanorod thin films promise broadband, broad angle performance for such coatings. We demonstrate that a bandwidth increase from 38.5% to 113% is possible by using a simple evolutionary strategy to optimize the thin film material parameters. A two dimensional FDTD planewave periodic scattering approach is used to demonstrate additional performance increase by adding losses to a single layer. The same technique may be used for antireflective coatings for which no analytical solution exists, as is the case with dispersive, non-linear materials, special geometries, and coatings with metallic or ferromagnetic inclusions. A procedure is outlined for using the FDTD approach to obtain a map of reflection coefficients with respect to wavelength and incidence angle.

  5. Coating to enhance metal-polymer adhesion

    SciTech Connect

    Parthasarathi, A.; Mahulikar, D. [Olin Metals Research Laboratories, New Haven, CT (United States)

    1996-12-31

    An ultra-thin electroplated coating has been developed to enhance adhesion of metals to polymers. The coating was developed for microelectronic packaging applications where it greatly improves adhesion of metal leadframes to plastic molding compounds. Recent tests show that the coating enhances adhesion of different metals to other types of adhesives as well and may thus have wider applicability. Results of adhesion tests with this coating, as well as its other characteristics such as corrosion resistance, are discussed. The coating is a very thin transparent electroplated coating containing zinc and chromium. It has been found to be effective on a variety of metal surfaces including copper alloys, Fe-Ni alloys, Al alloys, stainless steel, silver, nickel, Pd/Ni and Ni-Sn. Contact resistance measurements show that the coating has little or no effect on electrical resistivity.

  6. Tailoring Thin Film-Lacquer Coatings for Space Applications

    NASA Technical Reports Server (NTRS)

    Peters, Wanda C.; Harris, George; Miller, Grace; Petro, John

    1998-01-01

    Thin film coatings have the capability of obtaining a wide range of thermal radiative properties, but the development of thin film coatings can sometimes be difficult and costly when trying to achieve highly specular surfaces. Given any space mission's then-nal control requirements, there is often a need for a variation of solar absorptance (alpha(sub s)), emittance (epsilon) and/or highly specular surfaces. The utilization of thin film coatings is one process of choice for meeting challenging thermal control requirements because of its ability to provide a wide variety of alpha(sub s)/epsilon ratios. Thin film coatings' radiative properties can be tailored to meet specific thermal control requirements through the use of different metals and the variation of dielectric layer thickness. Surface coatings can be spectrally selective to enhance radiative coupling and decoupling. The application of lacquer to a surface can also provide suitable specularity for thin film application without the cost and difficulty associated with polishing.

  7. Manufacturing and coating by kinetic energy metallization

    SciTech Connect

    Kang, S.W.

    1998-02-09

    The purpose of this effort was to theoretically model the underlying metal-coating phenomena when metal particles impact a metal surface at high velocities under room temperature conditions. The physical processes involved in the novel metal-coating process called Kinetic Energy Metallization (KEM) have been theoretically and numerically analyzed. A bonding model between the incident and the target metals has been proposed and preliminary numerical results agree reasonably well with the laboratory-obtained metal samples and suggest promise of validity for the present model. However, to put the proposed bonding model on a firmer basis further numerical effort is needed to be carried for various metals and operating conditions.

  8. Influence of Metal Properties on the Formation and Evolution of Metal Coatings During Mechanical Coating

    NASA Astrophysics Data System (ADS)

    Hao, Liang; Lu, Yun; Sato, Hiromasa; Asanuma, Hiroshi; Guo, Jie

    2013-06-01

    Powders of Cu, Ti, Ni, Fe, and Zn metals were used to prepare coatings on the surfaces of Al2O3 balls by the mechanical coating technique. The coated Al2O3 balls were characterized with XRD and SEM. The results showed that all the metal powders except Ni formed continuous metal coatings. The evolution of metal coatings during mechanical coating was also investigated. The analysis indicates that as long as continuous metal coatings can be formed, the evolution can fall into the following stages: nucleation, formation and coalescence of discrete islands, formation and thickening of continuous coatings, and exfoliation of continuous coatings. Electronegativity of the metal was shown to have a major effect on the adhesion of the tiny metal particles on the surfaces of the Al2O3 balls during the initial stage of mechanical coating. The lower the electronegativity of the metal, the greater the coverage of the metal on the Al2O3 ball and the easier the adhesion of the tiny metal particles. Further, the better the plastic deformability of metal, the easier the cold welding among metal powder particles and the greater the thickness of the continuous metal coatings.

  9. Metal strip coating by electron beam PVD—industrial requirements and customized solutions

    Microsoft Academic Search

    E. Reinhold; J. Richter; U. Seyfert; C. Steuer

    2004-01-01

    During the last few years, the thin film applications in the metallurgical industries have been extended widely. Besides the aim of corrosion protection of strip steel, many coating tasks became an urgent issue, i.e., optical coatings, catalytic coatings, protection coatings, and other functional coatings on various metal strips as stainless steel strips, copper strips, and aluminium strips.This paper compares high-rate

  10. Fabrication of Metal-Insulator-Metal Junction with Metallic Conductive Langmuir-Blodgett Films

    NASA Astrophysics Data System (ADS)

    Mochizuki, Kengo; Ohnuki, Hitoshi; Ikegami, Keiichi; Imakubo, Tatsuro; Izumi, Mitsuru

    The Langmuir-Blodgett (LB) technique can deposit a soft coating without damaging the substrate. Thus, the technique is appropriate for coating fragile materials such as nano-structures and biomaterials. We fabricated electrical contacts on a dodecanethiol self-assembled monolayer (C12 SAM) using metallic conductive LB films of BEDO-TTF/stearic acid. We then prepared a metal-insulator-metal (MIM) junction, in which the C12 SAM was sandwiched between the LB films and Au surface. The current-voltage characteristics across the MIM junction exhibited nonlinear behavior, which suggests that tunneling is the dominant conduction mechanism. The tunneling characteristic parameters calculated using the Simmons tunneling model were in agreement with previous reports. These results show that metallic conductive LB films can serve as a soft electrode for use with delicate materials.

  11. Cellulose acetate coated mercury film electrodes for anodic stripping voltametry

    SciTech Connect

    Wang, J.; Hutchins-Kumar, L.D.

    1986-02-01

    The response characteristics and analytical advantages of cellulose acetate coated mercury film electrodes for anodic stripping measurements of trace metals are described. The coating provides an effective barrier of the mercury surface, thus eliminating the effects of various organic surfactants. For example, up to at least 100 ppm gelatin does not alter the response. The diagnostic power of rotating disk measurements is used to evaluate the transport toward the mercury surface. The response is limited by the permeability of the film, thus allowing stripping measurements in systems with poorly controlled mass transport. Base hydrolysis of the film is used to manipulate the permeability. Scanning electron micrographs show the microstructures of the films following different hydrolysis times. The discriminative properties of these coatings can be used also to improve the resolution between two adjacent stripping peaks. The response of the modified electrode is directly proportional to the analyte concentration and is reproducible. With a 10-min deposition time, detection limits are 7 x 10 M lead and 1.3 x 10 Z M cadmium. Various metal ions and organic surfactants are tested. The performance of this novel electrode system is compared to that of a conventional mercury film electrode. 19 references, 9 figures, 2 tables.

  12. Implantation and deposition of adherent metal-oxide ceramic coatings

    SciTech Connect

    Wood, B.P.; Henins, I.; Bartsch, R.R.; Walter, K.C. [Los Alamos National Lab., NM (United States)

    1995-12-31

    Firing a cathodic-arc at a pulse biased target in a low pressure background of oxygen allows very adherent coatings of metal-oxide ceramics to be deposited. Due to the high density of the metal-ion plasma and the high voltage of the pulse bias (50 kV), a relatively conformal implant can be achieved. This implanted metal layer stitches the metal-oxide coating to the surface and provides a graded interface which resists delamination. The authors present characterization of the metal-ion and carbon plasmas created by a cathodic-arc, discuss the effect of varying the relative phase of the cathodic-arc and target bias pulses, examine the conformality of ceramic and diamond-like-carbon films deposited on complicated shapes, and provide evidence of increased adherence due to the implantation step.

  13. Infiltration processing of metal matrix composites using coated ceramic particulates

    NASA Astrophysics Data System (ADS)

    Leon-Patino, Carlos Alberto

    2001-07-01

    A new process was developed to fabricate particulate metal matrix composites (MMCs). The process involves three steps: (1) modifying the particulate surface by metal coating, (2) forming a particulate porous compact; and (3) introducing metal into the channel network by vacuum infiltration. MMCs with different reinforcements, volume fractions, and sizes can be produced by this technique. Powders of alumina and silicon carbide were successfully coated with nickel and copper in preparation for infiltration with molten aluminum. Electroless Ni and Cu deposition was used since it enhances the wettability of the reinforcements for composite fabrication. While Cu deposits were polycrystalline, traces of phosphorous co-deposited from the electroless bath gave an amorphous Ni-P coating. The effect of metal coating on wetting behavior was evaluated at 800°C on plain and metal-coated ceramic plates using a sessile drop technique. The metallic films eliminated the non-wetting behavior of the uncoated ceramics, leading to equilibrium contact angles in the order of 12° and below 58° for Ni and Cu coated ceramics, respectively. The spreading data indicated that local diffusion at the triple junction was the governing mechanism of the wetting process. Precipitation of intermetallic phases in the drop/ceramic interface delayed the formation of Al4C3. Infiltration with molten Al showed that the coated-particulates are suitable as reinforcing materials for fabricating MMCs, giving porosity-free components with a homogeneously distributed reinforcing phase. The coating promoted easy metal flow through the preform, compared to the non-infiltration behavior of the uncoated counterparts. Liquid state diffusion kinetics due to temperature dependent viscosity forces controlled the infiltration process. Microstructural analysis indicated the formation of intermetallic phases such as CuAl 2, in the case of Cu coating, and Ni2Al3 and NiAl 3 when Ni-coated powders were infiltrated. The overall Ni and Cu content increased from bottom to top of the samples due to dissolution of the metal film by the stream of liquid Al during infiltration. The strengths of the Al/Ni-SiC composites, measured by four-point bending, were 205 and 225 MPa for samples reinforced with 78 mum and 49 mum Ni-SiC, respectively. The mode of fracture was mainly controlled by SiC particle fracture.

  14. Metal-coated optical fiber damage sensors

    NASA Astrophysics Data System (ADS)

    Chang, Chia-Chen; Sirkis, James S.

    1993-07-01

    A process which uses electroplating methods has been developed to fabricate metal coated optical fiber sensors. The elastic-plastic characteristics of the metal coatings have been exploited to develop a sensor capable of `remembering' low velocity impact damage. These sensors have been investigated under uniaxial tension testing of unembedded sensors and under low velocity impact of graphite/epoxy specimens with embedded sensors using both Michelson and polarimetric optical arrangements. The tests show that coating properties alter the optical fiber sensor performance and that the permanent deformation in the coating can be used to monitor composite delamination/impact damage.

  15. New transparent conductive films: FTO coated ITO

    Microsoft Academic Search

    Takuya Kawashima; Hiroshi Matsui; Nobuo Tanabe

    2003-01-01

    New transparent conductive films, fluorine doped tin oxide (FTO) films coated on indium-tin-oxide (ITO) films, were developed. These transparent conductive films were prepared by the spray pyrolysis deposition method at a substrate temperature of 350 °C in ITO and 400 °C in FTO. For ITO deposition, an ethanol solution of indium(III) chloride, InCl3·4H2O, and tin(II) chloride, SnCl2·2H2O [Sn\\/(In+Sn), 5 at.%

  16. Soluble Aromatic Polyimides For Film Coating

    NASA Technical Reports Server (NTRS)

    St. Clair, Anne K.; St. Clair, Terry L.

    1989-01-01

    Because of toughness, flexibility, and remarkable thermal stability, linear all-aromatic polyimides excellent candidate film and coating materials for advanced electronic circuitry and wires. Study determined effects on solubility of changing isomeric points of attachment of phenoxy units in diamine portions of several all-aromatic polyimides. Tough, flexible, transparent films produced by thermally converting polyamic acids to polyimides at 300 degree C in air. Potential for electronic applications excellent.

  17. INELASTIC CONTACT DEFORMATION OF METAL COATED FIBERS

    E-print Network

    Wadley, Haydn

    ) which are evaluated using the ®nite element method. A simple model for the consolidation of coated SiC deposition of the matrix onto a ceramic reinforcing ®ber (e.g. SiC, Al2O3) held at a relatively lowINELASTIC CONTACT DEFORMATION OF METAL COATED FIBERS D. M. ELZEY, R. GAMPALA* and H. N. G. WADLEY

  18. Thin Films for Coating Nanomaterials

    Microsoft Academic Search

    S. M. Mukhopadhyay; P. Joshi; R. V. Pulikollu

    2005-01-01

    For nano-structured solids (those with one or more dimensions in the 1-100 nm range), attempts of surface modification can pose significant and new challenges. In traditional materials, the surface coating could be several hundreds nanometers in thickness, or even microns and millimeters. In a nano-structured material, such as particle or nanofibers, the coating thickness has to be substantially smaller than

  19. On Coating Durability of Polymer Coated Sheet Metal under Plastic Deformation

    E-print Network

    Huang, Yu-Hsuan

    2011-08-08

    Polymer coated sheet metal components find diverse applications in many industries. The manufacturing of the components generally involves forming of sheet metal into the desired shape and coating of the formed part with organic coating...

  20. Antimicrobial edible films and coatings.

    PubMed

    Cagri, Arzu; Ustunol, Zeynep; Ryser, Elliot T

    2004-04-01

    Increasing consumer demand for microbiologically safer foods, greater convenience, smaller packages, and longer product shelf life is forcing the industry to develop new food-processing, cooking, handling, and packaging strategies. Nonfluid ready-to-eat foods are frequently exposed to postprocess surface contamination, leading to a reduction in shelf life. The food industry has at its disposal a wide range of nonedible polypropylene- and polyethylene-based packaging materials and various biodegradable protein- and polysaccharide-based edible films that can potentially serve as packaging materials. Research on the use of edible films as packaging materials continues because of the potential for these films to enhance food quality, food safety, and product shelf life. Besides acting as a barrier against mass diffusion (moisture, gases, and volatiles), edible films can serve as carriers for a wide range of food additives, including flavoring agents, antioxidants, vitamins, and colorants. When antimicrobial agents such as benzoic acid, sorbic acid, propionic acid, lactic acid, nisin, and lysozyme have been incorporated into edible films, such films retarded surface growth of bacteria, yeasts, and molds on a wide range of products, including meats and cheeses. Various antimicrobial edible films have been developed to minimize growth of spoilage and pathogenic microorganisms, including Listeria monocytogenes, which may contaminate the surface of cooked ready-to-eat foods after processing. Here, we review the various types of protein-based (wheat gluten, collagen, corn zein, soy, casein, and whey protein), polysaccharide-based (cellulose, chitosan, alginate, starch, pectin, and dextrin), and lipid-based (waxes, acylglycerols, and fatty acids) edible films and a wide range of antimicrobial agents that have been or could potentially be incorporated into such films during manufacture to enhance the safety and shelf life of ready-to-eat foods. PMID:15083740

  1. Polyvinyl acetate-based film coatings.

    PubMed

    Kolter, K; Dashevsky, A; Irfan, Muhamad; Bodmeier, R

    2013-12-01

    Polyvinyl acetate-based colloidal aqueous polymer dispersion Kollicoat(®) SR 30 D results in coatings characterized by moderate swelling behaviour, lipophilicity, pH-independent permeability for actives and high flexibility to withstand mechanical stress and is therefore used for controlled release coating. The colloidal aqueous polymer dispersion of Kollicoat(®) SR 30 D can be easily processed due to an optimal low minimum film forming temperature (MFT) of 18 °C without plasticizer addition and a thermal after-treatment (curing) of coated pellets. The drug release from Kollicoat(®) SR 30 D coated pellets was almost pH independent. Drug release could be easily adjusted by coating level or addition of soluble pore forming polymers. Physically stable Kollicoat(®) SR 30 D dispersions were obtained with the water-soluble polymers Kollidon(®) 30 and Kollicoat(®) IR up to 50% w/w. The addition of only 10% w/w triethyl citrate as plasticizer improved the flexibility of the films significantly and allowed compaction of the pellets. The drug release was almost independent of the compression force and the pellet content of the tablets. The inclusion of various tableting excipients slightly affected the drug release, primarily because of a different disintegration rate of the tablets. A combination of Kollicoat(®) SR 30 D and Kollicoat(®) IR with higher coating levels>10 mg/cm(2) is a relatively new alternative to OROS system which does not require drilling. PMID:24076229

  2. Molecular Level Coating for Metal Oxide Particles

    NASA Technical Reports Server (NTRS)

    McDaniel, Patricia R. (Inventor); Saint Clair, Terry L. (Inventor)

    2000-01-01

    Polymer encapsulated metal oxide particles are prepared by combining a polyamide acid in a polar aprotic solvent with a metal alkoxide solution. The polymer was imidized and the metal oxide formed simultaneously in a refluxing organic solvent. The resulting polymer-metal oxide is an intimately mixed commingled blend, possessing synergistic properties of both the polymer and preceramic metal oxide. The encapsulated metal oxide particles have multiple uses including, being useful in the production of skin lubricating creams, weather resistant paints, as a filler for paper, making ultraviolet light stable filled printing ink, being extruded into fibers or ribbons, and coatings for fibers used in the production of composite structural panels.

  3. Molecular Level Coating of Metal Oxide Particles

    NASA Technical Reports Server (NTRS)

    McDaniel, Patricia R. (Inventor); St.Clair, Terry L. (Inventor)

    2002-01-01

    Polymer encapsulated metal oxide particles are prepared by combining a polyamide acid in a polar osmotic solvent with a metal alkoxide solution. The polymer was imidized and the metal oxide formed simultaneously in a refluxing organic solvent. The resulting polymer-metal oxide is an intimately mixed commingled blend, possessing, synergistic properties of both the polymer and preceramic metal oxide. The encapsulated metal oxide particles have multiple uses including, being useful in the production of skin lubricating creams, weather resistant paints, as a filler for paper. making ultraviolet light stable filled printing ink, being extruded into fibers or ribbons, and coatings for fibers used in the production of composite structural panels.

  4. Metal/dielectric/metal sandwich film for broadband reflection reduction.

    PubMed

    Jen, Yi-Jun; Lakhtakia, Akhlesh; Lin, Meng-Jie; Wang, Wei-Hao; Wu, Huang-Ming; Liao, Hung-Sheng

    2013-01-01

    A film comprising randomly distributed metal/dielectric/metal sandwich nanopillars with a distribution of cross-sectional diameters, displayed extremely low reflectance over the blue-to-red regime, when coated on glass and illuminated normally. When it is illuminated by normally incident light, this sandwich film (SWF) has a low extinction coefficient, its phase thickness is close to a negative wavelength in the blue-to-red spectral regime, and it provides weakly dispersive forward and backward impedances, so that reflected waves from the two faces of the SWF interfere destructively. Broadband reflection-reduction, over a wide range of incidence angles and regardless of the polarization state of the incident light, was observed when the SWF was deposited on polished silicon. PMID:23591704

  5. Metal/dielectric/metal sandwich film for broadband reflection reduction

    PubMed Central

    Jen, Yi-Jun; Lakhtakia, Akhlesh; Lin, Meng-Jie; Wang, Wei-Hao; Wu, Huang-Ming; Liao, Hung-Sheng

    2013-01-01

    A film comprising randomly distributed metal/dielectric/metal sandwich nanopillars with a distribution of cross-sectional diameters, displayed extremely low reflectance over the blue-to-red regime, when coated on glass and illuminated normally. When it is illuminated by normally incident light, this sandwich film (SWF) has a low extinction coefficient, its phase thickness is close to a negative wavelength in the blue-to-red spectral regime, and it provides weakly dispersive forward and backward impedances, so that reflected waves from the two faces of the SWF interfere destructively. Broadband reflection-reduction, over a wide range of incidence angles and regardless of the polarization state of the incident light, was observed when the SWF was deposited on polished silicon. PMID:23591704

  6. Metal/dielectric/metal sandwich film for broadband reflection reduction

    NASA Astrophysics Data System (ADS)

    Jen, Yi-Jun; Lakhtakia, Akhlesh; Lin, Meng-Jie; Wang, Wei-Hao; Wu, Huang-Ming; Liao, Hung-Sheng

    2013-04-01

    A film comprising randomly distributed metal/dielectric/metal sandwich nanopillars with a distribution of cross-sectional diameters, displayed extremely low reflectance over the blue-to-red regime, when coated on glass and illuminated normally. When it is illuminated by normally incident light, this sandwich film (SWF) has a low extinction coefficient, its phase thickness is close to a negative wavelength in the blue-to-red spectral regime, and it provides weakly dispersive forward and backward impedances, so that reflected waves from the two faces of the SWF interfere destructively. Broadband reflection-reduction, over a wide range of incidence angles and regardless of the polarization state of the incident light, was observed when the SWF was deposited on polished silicon.

  7. The Penetrability of a Thin Metallic Film Inside the RF Field

    Microsoft Academic Search

    Yongxiang Zhao; I. Ben-Zvi; Xiangyun Chang; T. Rao; Wei Chen; R. Nardo

    2005-01-01

    Thin metallic film was widely applied in various areas. Especially, recently we are planning to apply it in a “Secondary emission enhanced photo-injector”, in which a diamond cathode is coated with a metallic film on its back to serve as a current path. The thickness of the film is originally considered to be in the order of 10 nm, which

  8. Characterization of Thin Films and Coatings

    SciTech Connect

    Baer, Donald R.; Thevuthasan, Suntharampillai

    2010-01-01

    Just as the numbers and types of thin films have grown dramatically, the needs and approaches for their characterization have also expanded significantly. Adequate characterization of a film or coating depends on the process to create the coating as well as the planned or potential application(s) and expected lifetime. Characterization of a coating or film necessarily requires application of methods that determine properties of the coating and not primarily the substrate. This places some focus on methods that determine properties of layers and not "bulk" material. However, the increasing importance of micro- and nano-structures in coatings and films places an increased importance in methods with high spatial resolution. The growing use of organic films and coatings and the importance of molecular functionalization of inorganic surfaces increase the importance for different types of molecular characterization tools. In most circumstances appropriate characterization requires use of a combination of tools. The purpose of this chapter is to provide an introduction to the basic methods and overview applications for some of the most important tools for characterization of films, coatings and surfaces. The chapter will be organized in six sections: • Technique Overview – This section provides a high level summary of the types of information that can be obtained by different methods and includes information about their sensitivity and resolution. • Incident Photon Methods – Techniques involving incident photons are described and some brief examples of application are shown. Methods included are: x-ray photoelectron spectroscopy (XPS), x-ray diffraction (XRD), x-ray reflectivity (XRR), Fourier transform infra-red spectroscopy (FTIR), laser Raman spectroscopy, ellipsometry, and photoluminescence spectroscopy. • Incident Ion Methods - Methods initiated by ion irradiation are summarized including: Rutherford backscattering spectrometry (RBS), nuclear reaction analysis (NRA), ion channeling, elastic recoil detection analysis (ERDA), secondary ion mass spectrometry (SIMS), glow discharge mass spectrometry and uses of focused ion beams (FIB) (often in combination with scanning electron microscopy). • Incident Electron Methods – Methods involving incident electrons include: Auger electron spectroscopy (AES), scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDS), transmission electron microscopy (TEM), and electron diffraction (low energy electron diffraction [LEED] and reflection high energy electron diffraction [RHEED]). • Other Methods – Additional methods described include scanning probe microscopy (SPM) (including scanning tunneling microscopy [STM] and atomic force microscopy [AFM]) and atom probe microscopy.

  9. Investigation of thin film coating process for printed electronics with suspension ink by slot die coating

    NASA Astrophysics Data System (ADS)

    Lee, Seung-Hyun; Kim, Inyoung

    2012-11-01

    Slot die coating process can be easily combined with roll-to-roll process and handle various coating liquid with wide range of viscosity and solid content. It is also pre-metered coating and the thickness of the coated layer can be easily predicted and controlled by a given feed flow rate and coating speed. Therefore, recently, slot die coating process is extending the use of fabrication of thin film printed electronics such as transparent conductive film and thin film solar cell etc. In the present study, we elucidated thin film coating process for printed electronics with suspension ink by slot die coating. Numerical study was investigated the effect of coating die design and rheological characteristics of suspension ink on coating uniformity. Slot die coating experiments was also performed with suspension ink which is composed of Cu(InGa)Se2 nano-particle and ethanol solvent and compared with numerical simulation.

  10. Thin-film metal hydrides.

    PubMed

    Remhof, Arndt; Borgschulte, Andreas

    2008-12-01

    The goal of the medieval alchemist, the chemical transformation of common metals into nobel metals, will forever be a dream. However, key characteristics of metals, such as their electronic band structure and, consequently, their electric, magnetic and optical properties, can be tailored by controlled hydrogen doping. Due to their morphology and well-defined geometry with flat, coplanar surfaces/interfaces, novel phenomena may be observed in thin films. Prominent examples are the eye-catching hydrogen switchable mirror effect, the visualization of solid-state diffusion and the formation of complex surface morphologies. Thin films do not suffer as much from embrittlement and/or decrepitation as bulk materials, allowing the study of cyclic absorption and desorption. Therefore, thin-metal hydride films are used as model systems to study metal-insulator transitions, for high throughput combinatorial research or they may be used as indicator layers to study hydrogen diffusion. They can be found in technological applications as hydrogen sensors, in electrochromic and thermochromic devices. In this review, we discuss the effect of hydrogen loading of thin niobium and yttrium films as archetypical examples of a transition metal and a rare earth metal, respectively. Our focus thereby lies on the hydrogen induced changes of the electronic structure and the morphology of the thin films, their optical properties, the visualization and the control of hydrogen diffusion and on the study of surface phenomena and catalysis. PMID:18980236

  11. Edible Films and Coatings for Meat and Poultry

    Microsoft Academic Search

    Zey Ustunol

    \\u000a Edible films and coatings are defined as continuous matrices that can be prepared from proteins, polysaccharides and\\/or lipids\\u000a to alter the surface characteristics of a food. Although the terms films and coatings are used interchangeably, films in general\\u000a are preformed and are freestanding, whereas, coatings are formed directly on the food product. Proteins used in edible films\\u000a include wheat gluten,

  12. Ultrathin metallic coatings can induce quantum levitation between nanosurfaces

    NASA Astrophysics Data System (ADS)

    Boström, Mathias; Ninham, Barry W.; Brevik, Iver; Persson, Clas; Parsons, Drew F.; Sernelius, Bo E.

    2012-06-01

    There is an attractive Casimir-Lifshitz force between two silica surfaces in a liquid (bromobenze or toluene). We demonstrate that adding an ultrathin (5-50 Å) metallic nanocoating to one of the surfaces results in repulsive Casimir-Lifshitz forces above a critical separation. The onset of such quantum levitation comes at decreasing separations as the film thickness decreases. Remarkably, the effect of retardation can turn attraction into repulsion. From that we explain how an ultrathin metallic coating may prevent nanoelectromechanical systems from crashing together.

  13. Covering solid, film cooled surfaces with a duplex thermal barrier coating

    NASA Technical Reports Server (NTRS)

    Liebert, C. H. (inventor)

    1983-01-01

    Thermal barrier coating systems were applied to hardware having passageways in the walls connecting apertures in the surface to a gas supply for film cooling. An inert gas, such as argon, is discharged through the apertures during the application of the thermal barrier coating system by plasma spraying. This flow of inert gas reduces both blocking of the holes and base metal oxidation during the coating operation.

  14. High temperature barrier coatings for refractory metals

    NASA Technical Reports Server (NTRS)

    Malone, G. A.; Walech, T.

    1995-01-01

    Improvements in high temperature oxidation resistant metal coating technology will allow NASA and commercial entities to develop competitive civil space transport and communication systems. The success of investigations completed in this program will have a positive impact on broadening the technology base for high temperature materials. The work reported herein describes processes and procedures for successfully depositing coherent oxidation barrier coatings on refractory metals to prevent degradation under very severe operating environments. Application of the new technology developed is now being utilized in numerous Phase 3 applications through several prominent aerospace firms. Major achievements have included: (1) development of means to deposit thick platinum and rhodium coatings with lower stress and fewer microcracks than could be previously achieved; (2) development of processes to deposit thick adherent coatings of platinum group metals on refractory substrates that remain bonded through high temperature excursions and without need for intermediate coatings (bonding processes unique to specific refractory metals and alloys have been defined; (3) demonstration that useful alloys of refractory and platinum coatings can be made through thermal diffusion means; (4) demonstration that selected barrier coatings on refractory substrates can withstand severe oxidizing environments in the range of 1260 deg and 1760 deg C for long time periods essential to the life requirements of the hardware; and (5) successful application of the processes and procedures to prototype hardware. The results of these studies have been instrumental in improved thermal oxidation barrier coatings for the NASP propulsion system. Other Phase 3 applications currently being exploited include small uncooled thrusters for spacecraft and microsatellite maneuvering systems.

  15. Rapidly solidified metal coatings by peen plating

    NASA Technical Reports Server (NTRS)

    Chu, H. P.

    1987-01-01

    Specimens of 7075-T6 aluminum alloy were peen plated with rapidly solidified tin-lead and aluminum powders, and the cross-sections of the coated specimens were examined by light and electron microscopy. The properties of the peen plated specimens were also compared with those of shot peened specimens without any coating. It is found that peen plating with rapidly solidified metals improves the fatigue properties of the coated samples to a greater extent than shot peening alone. Specimens of 7075-T6 alloy peen plated with rapidly solidified tin-lead and aluminum exhibited better fatigue resistance than shot peened specimens in both air and salt water.

  16. Metallic seal for thermal barrier coating systems

    NASA Technical Reports Server (NTRS)

    Miller, Robert A. (inventor)

    1990-01-01

    The invention is particularly concerned with sealing thermal barrier coating systems of the type in use and being contemplated for use in diesel and other internal combustion engines. The invention also would find application in moderately high temperature regions of gas turbine engines and any other application employing a thermal barrier coating at moderate temperatures. Ni-35Cr-6Al-1Y, Ni-35Cr-6Al-1Yb, or other metallic alloy denoted as MCrAlx is applied over a zirconia-based thermal barrier overlayer. The close-out layer is glass-bead preened to densify its surface. This seals and protects the thermal barrier coating system.

  17. Deposition and characterization of metal sulfide dielectric coatings for hollow glass waveguides

    E-print Network

    , and J. A. Harrington, "Processing and characterization of silver films used to fabricate hollow glass of thin film uniformity in hollow glass waveguides," Opt. Eng. 38, 2009-2015 (1999). 16. M. OhringDeposition and characterization of metal sulfide dielectric coatings for hollow glass waveguides

  18. Applications of thin carbon coatings and films in injection molding

    NASA Astrophysics Data System (ADS)

    Cabrera, Eusebio Duarte

    In this research, the technical feasibility of two novel applications of thin carbon coatings is demonstrated. The first application consists of using thin carbon coatings on molds for molding ultra-thin plastic parts (<0.5 mm thickness) with lower pressures by promoting wall slip. The second application consists of a new approach to provide electromagnetic interference (EMI) shielding for plastic parts using in mold coated nanoparticle thin films or nanopapers to create a conductive top layer. During this research, the technical feasibility of a new approach was proven which provides injection molding of ultra-thin parts at lower pressures, without the need of fast heating/fast cooling or other expensive mold modification. An in-house developed procedure by other members of our group, was employed for coating the mold surface using chemical vapor deposition (CVD) resulting in a graphene coating with carbide bonding to the mold surface. The coating resulted in a significant decrease of surface friction and consequently easiness of flow when compared to their uncoated counterparts. Thermoplastic polymers and their composites are a very attractive alternative but are hindered by the non-conductive nature of polymers. There are two general approaches used to date to achieve EMI shielding for plastic products. One is to spray a conductive metal coating onto the plastic surface forming a layer that must maintain its shielding effectiveness (SE), and its adhesion to the plastic throughout the expected life of the product. However, metal coatings add undesirable weight and tend to corrode over time. Furthermore, scratching the coating may create shielding failure; therefore, a protective topcoat may be required. The other approach is to use polymer composites filled with conductive fillers such as carbon black (CB), carbon nanofiber (CNF), and carbon nanotube (CNT). While conductive fillers may increase the electrical conductivity of polymer composites, the loading of such fillers often cannot reach a high level (<10 wt. %) due to the dispersion difficulty and exponential increase in viscosity. In this research, the technical feasibility of a new approach to EMI shielding of plastic parts was proven using in mold coated nanoparticle thin films or nanopapers to create a conductive top layer. For many years, in-mold coating (IMC) has been commercially applied to Sheet Molding Compound (SMC) compression molded parts, as an environmentally friendly approach to improve its surface quality and provide the required conductivity for electrostatic painting using carbon black (CB). Such process can also be applied to injection molding for creating a top conductive layer. Increasing the amount of CB will increase the surface conductivity of the coated part, thus improving the paint transfer efficiency. However the CB levels needed to achieve the conductivity levels required for achieving EMI shielding would make the coating viscosity too large for proper coating. Nanopaper based composites are excellent candidates for EMI shielding because of the nanopaper's high concentration of carbon nanofibers (CNFs) (~2 wt% to 10 wt% depending on nanopaper/thermoplastic thickness and 71wt.% to 79wt.% in the nanopaper itself after resin infusion) and high conductivity of the nanopaper. Instead of premixing nanoparticles with IMC coating, nanopapers enable the use of low viscosity IMC without CB coating to impregnate the CNF network in order to reach high electrical conductivity and EMI shielding values. (Abstract shortened by UMI.).

  19. Aerosol chemical vapor deposition of metal oxide films

    DOEpatents

    Ott, Kevin C. (4745 Trinity Dr., Los Alamos, NM 87544); Kodas, Toivo T. (5200 Noreen Dr. NE., Albuquerque, NM 87111)

    1994-01-01

    A process of preparing a film of a multicomponent metal oxide including: forming an aerosol from a solution comprised of a suitable solvent and at least two precursor compounds capable of volatilizing at temperatures lower than the decomposition temperature of said precursor compounds; passing said aerosol in combination with a suitable oxygen-containing carrier gas into a heated zone, said heated zone having a temperature sufficient to evaporate the solvent and volatilize said precursor compounds; and passing said volatilized precursor compounds against the surface of a substrate, said substrate having a sufficient temperature to decompose said volatilized precursor compounds whereby metal atoms contained within said volatilized precursor compounds are deposited as a metal oxide film upon the substrate is disclosed. In addition, a coated article comprising a multicomponent metal oxide film conforming to the surface of a substrate selected from the group consisting of silicon, magnesium oxide, yttrium-stabilized zirconium oxide, sapphire, or lanthanum gallate, said multicomponent metal oxide film characterized as having a substantially uniform thickness upon said FIELD OF THE INVENTION The present invention relates to the field of film coating deposition techniques, and more particularly to the deposition of multicomponent metal oxide films by aerosol chemical vapor deposition. This invention is the result of a contract with the Department of Energy (Contract No. W-7405-ENG-36).

  20. Use of 2-hydroxylhydrazine as a new modifier in dip-coating nickel films

    Microsoft Academic Search

    R. Syukri; Yusuke Ito; Takayuki Ban; Yutaka Ohya; Yasutaka Takahashi

    2002-01-01

    A modified version of the dip-coating technique, which uses 2-hydroxylhydrazine as a mild reducing agent, was applied in the fabrication of nickel thin films. Nickel acetate was used as metal source. Metallic nickel thin films were formed on glass substrates by firing in the range of 400–600 °C under nitrogen atmosphere. The deposited layers were composed of cubic Ni crystallites.

  1. Fatigue-Resistance Enhancements by Glass-Forming Metallic Films

    SciTech Connect

    Liu, F. X. [University of Tennessee, Knoxville (UTK); Liaw, Peter K [University of Tennessee, Knoxville (UTK); Jiang, W. H. [University of Tennessee, Knoxville (UTK); Chiang, C L [National Taiwan Ocean University; Gao, Yanfei [ORNL; Guan, Y F [University of Tennessee, Knoxville (UTK); Chu, J. P. [National Taiwan Ocean University; Rack, P. D. [University of Tennessee, Knoxville (UTK)

    2007-01-01

    Zr-based glass-forming metallic films were coated on a 316L stainless steel and a Ni-based alloy by the magnetron-sputter deposition. Four-point-bending fatigue tests were conducted on those coated materials with the film surface on the tensile side. Results showed that the fatigue life and fatigue-endurance limit of the materials could be considerably improved, and the enhancements vary with the maximum applied stress and the substrate material. Fractographs showed that the film remained well adhered to the substrate even after the severe plastic deformation. Surface-roughness measurements indicated the improvement of the surface finishes due to the deposition of the glass-forming film. Nanoindentation test results suggested that the thin film exhibited both high yield strength and good ductility. The reduction of the surface roughness, good adhesion between the film and the substrate, and the excellent strength and ductility of the glass-forming metallic film are the major factors for the fatigue-resistance enhancements of the coated material. A micromechanical model is developed to illustrate the mechanisms of fatigue-resistance enhancements through the interaction between the amorphous film and the substrate slip bands.

  2. Mixed metal oxide inorganic\\/organic coatings

    Microsoft Academic Search

    Chad R. Wold; Mark D. Soucek

    1998-01-01

    Mixed metal oxide ceramer coatings were developed using linseed oil as the organic phase with titanium i-propoxide, and zirconium\\u000a n-propoxide as the inorganic sol-gel precursors. The overall goal of this study was to develop a primer that will provide\\u000a corrosion protection and better adhesion to metal substrates with minimal environmental impact. Zinc acetate dihydrate was\\u000a introduced to the system as

  3. Peroxotungstic Acid Coated Films for Electrochromic Display Devices

    Microsoft Academic Search

    Kazusuke Yamanaka; Hiroshi Oakamoto; Hirokazu Kidou; Tetsuichi Kudo

    1986-01-01

    Peroxotungstic acid coated films were investigated for applications to electrochromic display devices. Films coated with peroxotungstic acid aqueous solutions exhibited electrochromism in non-aqueous electrolyte solutions containing Li-salts. A good reversibility for the electrochromic reaction was attained after several writing-erasing cycles involving linear sweeps when the films had been heat-treated at about 120°C for 1 h. Cathodic polarization of the coated

  4. High temperature barrier coatings for refractory metals

    Microsoft Academic Search

    G. A. Malone; T. Walech

    1995-01-01

    Improvements in high temperature oxidation resistant metal coating technology will allow NASA and commercial entities to develop competitive civil space transport and communication systems. The success of investigations completed in this program will have a positive impact on broadening the technology base for high temperature materials. The work reported herein describes processes and procedures for successfully depositing coherent oxidation barrier

  5. Polymer-assisted deposition of metal-oxide films

    Microsoft Academic Search

    Q. X. Jia; T. M. McCleskey; A. K. Burrell; Y. Lin; G. E. Collis; H. Wang; A. D. Q. Li; S. R. Foltyn

    2004-01-01

    Metal oxides are emerging as important materials for their versatile properties such as high-temperature superconductivity, ferroelectricity, ferromagnetism, piezoelectricity and semiconductivity. Metal-oxide films are conventionally grown by physical and chemical vapour deposition. However, the high cost of necessary equipment and restriction of coatings on a relatively small area have limited their potential applications. Chemical-solution depositions such as sol-gel are more cost-effective,

  6. Indium doped zinc oxide nanowire thin films for antireflection and solar absorber coating applications

    SciTech Connect

    Shaik, Ummar Pasha [ACRHEM, University of Hyderabad, Hyderabad-500046 (India); Krishna, M. Ghanashyam, E-mail: mgksp@uohyd.ac.in [ACRHEM and School of Physics, University of Hyderabad, Hyderabad-500046 (India)

    2014-04-24

    Indium doped ZnO nanowire thin films were prepared by thermal oxidation of Zn-In metal bilayer films at 500°C. The ZnO:In nanowires are 20-100 nm in diameter and several tens of microns long. X-ray diffraction patterns confirm the formation of oxide and indicate that the films are polycrystalline, both in the as deposited and annealed states. The transmission which is <2% for the as deposited Zn-In films increases to >90% for the ZnO:In nanowire films. Significantly, the reflectance for the as deposited films is < 10% in the region between 200 to 1500 nm and < 2% for the nanowire films. Thus, the as deposited films can be used solar absorber coatings while the nanowire films are useful for antireflection applications. The growth of nanowires by this technique is attractive since it does not involve very high temperatures and the use of catalysts.

  7. Bioactive glass coatings for orthopedic metallic implants

    SciTech Connect

    Lopez-Esteban, Sonia; Saiz, Eduardo; Fujino, Sigheru; Oku, Takeo; Suganuma, Katsuaki; Tomsia, Antoni P.

    2003-06-30

    The objective of this work is to develop bioactive glass coatings for metallic orthopedic implants. A new family of glasses in the SiO2-Na2O-K2O-CaO-MgO-P2O5 system has been synthesized and characterized. The glass properties (thermal expansion, softening and transformation temperatures, density and hardness) are in line with the predictions of established empirical models. The optimized firing conditions to fabricate coatings on Ti-based and Co-Cr alloys have been determined and related to the glass properties and the interfacial reactions. Excellent adhesion to alloys has been achieved through the formation of 100-200 nm thick interfacial layers (Ti5Si3 on Ti-based alloys and CrOx on Co-Cr). Finally, glass coatings, approximately 100 mu m thick, have been fabricated onto commercial Ti alloy-based dental implants.

  8. Plasmonic enhancement of thin-film solar cells using gold-black coatings

    Microsoft Academic Search

    Christopher J. Fredricksen; D. R. Panjwani; J. P. Arnold; P. N. Figueiredo; F. K. Rezaie; J. E. Colwell; K. Baillie; Samuel J. Peppernick; Alan G. Joly; Kenneth M. Beck; Wayne P. Hess; Robert E. Peale

    2011-01-01

    Coatings of conducting gold-black nano-structures on commercial thin-film amorphous-silicon solar cells enhance the short-circuit current by 20% over a broad spectrum from 400 to 800 nm wavelength. The efficiency, i.e. the ratio of the maximum electrical output power to the incident solar power, is found to increase 7% for initial un-optimized coatings. Metal blacks are produced cheaply and quickly in

  9. Optoacoustic method for determination of submicron metal coating properties: Theoretical consideration

    SciTech Connect

    Pelivanov, Ivan M.; Kopylova, Daria S.; Podymova, Natalia B.; Karabutov, Alexander A. [International Laser Center, M. V. Lomonosov Moscow State University, Moscow 119991 (Russian Federation)

    2009-07-01

    The goal of this work is theoretical consideration of the optoacoustic (OA) conversion in the system consisting of a metal film deposited on a transparent dielectric substrate and covered by a transparent liquid. This consideration implies a method for nondestructive evaluation of submicron metal coatings. The main principle of the method is the following. Irradiation of the metal film by a nanosecond laser pulse leads to transient heating and expansion of the film that in turn results in the generation of an acoustic signal. The waveform of the signal results from two contributions: the 'primary' signal from the thermal expansion of the metal film, which repeats the temporal profile of the laser pulse envelope, and the 'secondary' signal, which originates from the thermal expansion of the adjacent liquid layer. Due to low thermal conductivity of liquid compared to metal, the liquid accumulates heat that is released in metal and produces that secondary contribution into the OA conversion. This contribution is very sensitive to the properties of the film. The influence of the film thickness and its thermophysical parameters on the frequency-dependent efficiency of OA conversion and on the temporal profile of excited OA signals is discussed in detail. Based on these results, the method for nondestructive evaluation of submicron metal coatings properties is proposed.

  10. Wear Resistance of Coating Films on Hob Teeth

    NASA Astrophysics Data System (ADS)

    Umezaki, Yoji; Funaki, Yoshiyuki; Kurokawa, Syuhei; Ohnishi, Osamu; Doi, Toshiro

    The wear resistance of coating films on hob teeth is investigated through the simulated hobbing tests with a flytool. The coating films on hob teeth are titanium family ceramics such as TiN, TiCN, TiSiN and TiAlN and aluminum chromium family ceramics such as AlCrN and AlCrSiN. The wear of coated tools is shown about film thickness, film materials, ingredient ratio in a film component and the oxidization of coating films. The oxidization is clarified from a result of the influence on the crater wear progress through wear cutting tests in atmosphere of nitrogen gas or oxygen gas. The oxidization of TiAlN coating films produces oxide products on the tool rake face, and this oxidation relates to the amount of crater wear. The increase of aluminum concentration in the TiAlN film improves the crater wear resistance in air atmosphere, while it has a reverse effect in nitrogen gases. The AlCrSiN film has effective wear resistance against the abrasive wear and/or oxidization wear. The oxidation film formed on the AlCrSiN film is very firm and this suppresses the oxidation wear on the rake face and works against the abrasive wear advantageously.

  11. Effects of palladium coatings on oxygen sensors of titanium dioxide thin films

    Microsoft Academic Search

    L. Castañeda

    2007-01-01

    Titanium dioxide (TiO2-anatase phase) thin films were deposited by the ultrasonic spray pyrolysis technique employing titanium (IV) oxide acetylacetonate (TiO(acac)2) dissolved in pure methanol as a source material. In order to prepare oxygen sensors, TiO2 thin films were deposited on interdigitated gold electrodes with contacted alumina substrates. Palladium (Pd) coatings were carried out by vacuum thermal evaporation through a metallic

  12. Dip coating assisted polylactic acid deposition on steel surface: Film thickness affected by drag force and gravity

    Microsoft Academic Search

    Hsu-Wei Fang; Kuo-Yen Li; Tai-Lun Su; Thomas Chun-Kuang Yang; Ji-Sheng Chang; Po-Liang Lin; Wen-Chung Chang

    2008-01-01

    Dip coating process has the potential of providing an easier and economical way to form a polylactic acid (PLA) layer on metal surface for various applications. The effects of dip coating operating parameters such as the withdrawal velocity, concentration, and viscosity of the solution on the film thickness were investigated in this study. Our experimental results show that the increase

  13. A shape-recovery polymer coating for the corrosion protection of metallic surfaces.

    PubMed

    Lutz, Alexander; van den Berg, Otto; Van Damme, Jonas; Verheyen, Karen; Bauters, Erwin; De Graeve, Iris; Du Prez, Filip E; Terryn, Herman

    2015-01-14

    Self-healing polymer coatings are a type of smart material aimed for advanced corrosion protection of metals. This paper presents the synthesis and characterization of two new UV-cure self-healing coatings based on acrylated polycaprolactone polyurethanes. On a macroscopic scale, the cured films all show outstanding mechanical properties, combining relatively high Young's modulus of up to 270 MPa with a strain at break above 350%. After thermal activation the strained films recover up to 97% of their original length. Optical and electron microscopy reveals the self-healing properties of these coatings on hot dip galvanized steel with scratches and microindentations. The temperature-induced closing of such defects restores the corrosion protection and barrier properties of the coating as shown by electrochemical impedance spectroscopy and scanning vibrating electrode technique. Therefore, such coatings are a complementary option for encapsulation-based autonomous corrosion protection systems. PMID:25517028

  14. Sputtered metallic coatings for optical fibers used in high-temperature environments

    NASA Astrophysics Data System (ADS)

    Gunther, Michael F.; Zeakes, Jason S.; Lieber, Donald E.; May, Russell G.; Claus, Richard O.

    1994-05-01

    Rf and dc planar magnetron sputtering systems were used to deposit high-temperature nickel- based super alloys, INCONEL 617, 625, Haynes 214, and thin films of palladium, as coatings on optical fibers for use in temperatures approaching 1000 degree(s)C. The nickel-based alloy coatings were applied on-line as the optical fiber was drawn, minimizing the exposure of the fiber to the deleterious effects of humidity. The thin film coatings of pure metals were sputtered using a new rf magnetron sputtering system custom designed and built for the Fiber and Electro Optics Research Center. The resulting coatings were analyzed using scanning electron microscopy, Auger electron microscopy, and energy dispersive x-ray spectroscopy. The coated fibers exhibit promise for embedded sensors in high temperature, high load composites used for advanced aerospace and energy applications.

  15. Evaluation of a non-catalytic coating for metallic TPS

    NASA Technical Reports Server (NTRS)

    Pittman, C. M.; Brown, R. D.; Shideler, J. L.

    1984-01-01

    A commercially available ceramic coating was evaluated for application to metallic heat shields for Shuttle-type entry vehicles. Coated Inconel 617 specimens were subjected to thermal shock cycles, surface emittances were measured, and surface equilibrium temperatures were measured for coated and oxidized specimens exposed to an arc-tunnel environment. The coating adhered very well to the metal and appeared to be very non-catalytic.

  16. Polymer-assisted deposition of metal-oxide films.

    PubMed

    Jia, Q X; McCleskey, T M; Burrell, A K; Lin, Y; Collis, G E; Wang, H; Li, A D Q; Foltyn, S R

    2004-08-01

    Metal oxides are emerging as important materials for their versatile properties such as high-temperature superconductivity, ferroelectricity, ferromagnetism, piezoelectricity and semiconductivity. Metal-oxide films are conventionally grown by physical and chemical vapour deposition. However, the high cost of necessary equipment and restriction of coatings on a relatively small area have limited their potential applications. Chemical-solution depositions such as sol-gel are more cost-effective, but many metal oxides cannot be deposited and the control of stoichiometry is not always possible owing to differences in chemical reactivity among the metals. Here we report a novel process to grow metal-oxide films in large areas at low cost using polymer-assisted deposition (PAD), where the polymer controls the viscosity and binds metal ions, resulting in a homogeneous distribution of metal precursors in the solution and the formation of uniform metal-organic films. The latter feature makes it possible to grow simple and complex crack-free epitaxial metal-oxides. PMID:15258574

  17. Novel hydroxyapatite\\/tantalum surface coating for metallic dental implant

    Microsoft Academic Search

    M. H. Fathi; F. Azam

    2007-01-01

    The aim of this study was to design and produce a novel surface composite coating on metallic substrate in order to improve the biocompatibility of metallic dental implant and the bone osteointegration simultaneously.Stainless steel 316L (SS) was used as a metallic substrate and a novel double-layer hydroxyapatite\\/tantalum (HA\\/Ta) coating was prepared on it. Tantalum coating was made using physical vapor

  18. Preparation and Characterization of Ultrathin Films and Film Coatings for Microelectronics

    NASA Astrophysics Data System (ADS)

    Pogoryelov, Y. A.

    2004-06-01

    The work is devoted to the preparation and characterization of new thin metal film media for various types of non-volatile memories, and also to the development of new techniques for characterization of film parameters in microelectronics. We studied the physics of indirect exchange coupling in trilayer thin-film structures based on rear earth (Tb) and transition metals (Fe) with the nonmagnetic spacer (Au), which were prepared by electron-beam evaporation in an ultrahigh vacuum system. Investigations were carried out using magneto-optical and magneto-transport techniques, including know-how based on the Hall-like effect at zero applied external magnetic field. Oscillations of the Hall resistivity with the change of its sign, typical for the Ruderman-Kittel-Kasuya-Yosida model of exchange interactions, were experimentally observed. Also, a new method is presented for determining thermophysical parameters. It can be applied for non-contact and non-destructive investigation and monitoring of the adhesion of coatings or films to the substrate, both during and after deposition.

  19. Process for ultra smooth diamond coating on metals and uses thereof

    NASA Technical Reports Server (NTRS)

    Vohra, Yogesh K. (Inventor); Catledge, Shane A. (Inventor)

    2001-01-01

    The present invention provides a new process to deposit well adhered ultra smooth diamond films on metals by adding nitrogen gas to the methane/hydrogen plasma created by a microwave discharge. Such diamond coating process is useful in tribological/wear resistant applications in bio-implants, machine tools, and magnetic recording industry.

  20. Application of metallic coatings to powders by the vacuum deposition method (review)

    Microsoft Academic Search

    I. L. Roikh; N. N. Novikov

    1975-01-01

    Powdered and granulated substances are at present being increasingly used in various branches of industry. The range of uses of such substances can be considerably widened by applying to them film coatings of other materials for the purpose of encapsulating them or imparting to them special properties. Metal deposition makes it possible to obtain from polymer powders new types of

  1. Characterization of Starch and Composite Edible Films and Coatings

    Microsoft Academic Search

    María A. García; Adriana Pinotti; Miriam N. Martino; Noemí E. Zaritzky

    \\u000a Starch-based and composite edible films and coatings can enhance food quality, safety and stability. They can control mass\\u000a transfer between components within a product, as well as between product and environment. They can improve performance of\\u000a the product through the addition of antioxidants, antimicrobial agents, and other food additives. Unique advantages of edible\\u000a films and coatings can lead to the

  2. Assessment of ceramic coatings for metal fuel melting crucible

    SciTech Connect

    Kim, Ki-Hwan; Song, Hoon; Kim, Jong-Hwan; Oh, Seok-Jin; Kim, Hyung-Tae; Lee, Chan-Bock [Korea Atomic Energy Research Institute, Yuseong, Daejeon 305-600 (Korea, Republic of)

    2013-07-01

    The objective of this study is to develop a coating method and material for crucibles to prevent material interactions with the U-Zr/U-TRU-Zr fuels during the manufacturing of SFR fuels. Refractory coatings were applied to niobium substrates by vacuum plasma-spray coating method. Melt dipping tests conducted were the coated rods lowered into the fuel melt at 1600 C. degrees, and withdrawn and cooled outside the crucible in the inert atmosphere of the induction furnace. Melt dipping tests of the coated Nb rods indicated that plasma-sprayed Y{sub 2}O{sub 3} coating doesn't form significant reaction layer between fuel melt and coating layer. Melt dipping tests of the coated Nb rods showed that TiC, TaC, and Y{sub 2}O{sub 3} coatings exhibited the promising performance among other ceramic coatings. These materials could be promising candidate materials for the reusable melt crucible of metal fuel for SFR. In addition, in order to develop the vacuum plasma-spray coating method for re-usable crucible of metal fuel slugs to be overcome the issue of thermal expansion mismatch between coating material and crucible, various combinations of coating conditions were investigated to find the bonding effect on the substrate in pursuit of more effective ways to withstand the thermal stresses. It is observed that most coating methods maintained sound coating state in U-Zr melt. (authors)

  3. Metal-Film Hall-Effect Devices

    NASA Technical Reports Server (NTRS)

    Peters, Palmer N.

    1994-01-01

    Large positive and negative Hall coefficients achievable. Family of Hall-effect devices made from multilayer metal films instead of semiconductor materials. Metal films easier to fabricate; formed by deposition on variety of substrates, and leads readily attached to them. Fabricated with larger areas, potentially more reliable, and less affected by impurities. Also used to measure magnetic fields. Devices especially useful at low temperatures.

  4. Laser ultrasonic investigation of films and hard coatings

    NASA Astrophysics Data System (ADS)

    Murray, Todd W.; Guo, Zhiqi; Krishnaswamy, Sridhar; Achenbach, Jan D.

    2000-05-01

    Laser ultrasonic techniques are becoming increasingly more popular in the evaluation of films and coatings. A model combining theory and numerical analysis for the pulsed laser generation of ultrasound in an isotropic film on a semi-infinite substrate is presented. The model gives the time domain displacement of the system as a function of the density and mechanical properties of the film and substrate and the thermal properties of the film. It is particularly suited for the evaluation of hard coatings commonly used to protect materials against wear and abrasion and may be used to directly extract coating properties through comparison of experimental and theoretical data. The model has been verified experimentally using a 1 ns Nd:YAG laser source for acoustic wave generation and a stabilized Michelson interferometer for detection. Experiments have been carried out on a variety of film/substrate systems and the results show good agreement with theory.

  5. Application of polymer-coated glassy carbon electrodes to the direct determination of trace metals in body fluids by anodic tripping voltametry

    Microsoft Academic Search

    Boy. Hoyer; T. Mark. Florence

    1987-01-01

    This paper describes the use of a polymer-coated thin mercury film electrode for the direct determination of trace metals in body fluids by anodic stripping voltametry. The antifouling properties of the membrane coating greatly improve the analytical signal in comparison with the conventional thin mercury film electrode. Lead in whole blood, urine, and sweat and copper in sweat can be

  6. Properties of thick PZT films prepared by modified metal organic decomposition process

    Microsoft Academic Search

    Yi-Nein Lai; Cheng-Hsiung Lin; Hsiu-Fung Cheng; I-Nan Lin

    2001-01-01

    Characteristics of PZT films synthesized by using a modified metal-organic decompositions (MOD) process, which is the spin-coating of a nano-powder incorporated PZT carbaxylate solution, was examined. A deposition rate as large as 0.27 ? m per layer is achieved by carefully adjusting the concentration of carboxylate solution (0.4 M) and spin-coating process (2000 rpm). PZT films thus obtained possess good

  7. Mechanism facilitates coating of inner surfaces of metal cylinders

    NASA Technical Reports Server (NTRS)

    Billingsley, J. M.; Taft, A. R.

    1966-01-01

    Cylinder is rotated about shielded hot filament to vapor deposit thin coatings of aluminum or other metallic substances on the inner surface of a cylinder while avoiding heat-producing high-density current flow which causes outgassing of the coating surface. This method is acceptable for glass or metal.

  8. The effects of metal coating on the diffusion bonding in Al 2 O 3 \\/Inconel 600 and the modulus of rupture strength of alumina

    Microsoft Academic Search

    H. R. Hwang; R. Y. Lee

    1996-01-01

    Alumina with a sputter-deposited metal film was diffusion bonded to Inconel 600. A higher bonding strength and lower joining temperature were obtained with titanium coating compared to that for the non-coated sample. The improved joining behaviour was attributed to an enhanced interface reaction and reduction in the thermal stress. Also, the effect of various coatings of 3 µm thickness on

  9. Plasma sprayed and electrospark deposited zirconium metal diffusion barrier coatings

    SciTech Connect

    Hollis, Kendall J [Los Alamos National Laboratory; Pena, Maria I [Los Alamos National Laboratory

    2010-01-01

    Zirconium metal coatings applied by plasma spraying and electrospark deposition (ESD) have been investigated for use as diffusion barrier coatings on low enrichment uranium fuel for research nuclear reactors. The coatings have been applied to both stainless steel as a surrogate and to simulated nuclear fuel uranium-molybdenum alloy substrates. Deposition parameter development accompanied by coating characterization has been performed. The structure of the plasma sprayed coating was shown to vary with transferred arc current during deposition. The structure of ESD coatings was shown to vary with the capacitance of the deposition equipment.

  10. Spray coating of superhydrophobic and angle-independent coloured films.

    PubMed

    Ge, Dengteng; Yang, Lili; Wu, Gaoxiang; Yang, Shu

    2014-03-01

    Angle-independent coloured films with superhydrophobicity were fabricated from quasi-amorphous arrays of monodispersed fluorinated silica nanoparticles via one-step spray coating. The film exhibited a high contact angle (>150°) and a low roll-off angle (~2°) and the colour could be tuned to blue, green and moccasin by varying the size of the nanoparticles. PMID:24457894

  11. Process for forming a metal compound coating on a substrate

    DOEpatents

    Sharp, D.J.; Vernon, M.E.; Wright, S.A.

    1988-06-29

    A method of coating a substrate with a thin layer of a metal compound by forming a dispersion of an electrophoretically active organic colloid and a precursor of the metal compound in an electrolytic cell in which the substrate is an electrode. Upon application of an electric potential, the electrode is coated with a mixture of the organic colloid and the precursor to the metal compound, and the coated substrate is then heated in the presence of an atmosphere or vacuum to decompose the organic colloid and form a coating of either a combination of metal compound and carbon, or optionally forming a porous metal compound coating by heating to a temperature high enough to chemically react the carbon.

  12. Process for forming a metal compound coating on a substrate

    DOEpatents

    Sharp, Donald J. (Albuquerque, NM); Vernon, Milton E. (Albuquerque, NM); Wright, Steven A. (Albuquerque, NM)

    1991-01-01

    A method of coating a substrate with a thin layer of a metal compound by forming a dispersion of an electrophoretically active organic colloid and a precursor of the metal compound in an electrolytic cell in which the substrate is an electrode. Upon application of an electric potential, the electrode is coated with a mixture of the organic colloid and the precursor to the metal compound, and the coated substrate is then heated in the presence of an atmosphere or vacuum to decompose the organic colloid and form a coating of either a combination of metal compound and carbon, or optionally forming a porous metal compound coating by heating to a temperature high enough to chemically react the carbon.

  13. Thin Film Heater for Removable Volatile Protecting Coatings

    PubMed Central

    Karim, Abid

    2013-01-01

    Freshly coated aluminum mirrors have excellent reflectivity at far ultraviolet wavelengths. However, reflectivity rapidly degrades when the mirror surfaces are exposed to atmosphere. In order to avoid this problem, freshly coated aluminum surface can be protected by over-coating of a removable volatile protecting coating. This protecting coating can be re-evaporated by controlled heating or by some other methods when required. This type of removable coating has immediate application in UV space astronomy. The purpose of this paper is to demonstrate the feasibility of re-evaporation of removable volatile Zn protecting coating using a NiCr thin film heater without affecting the reflection properties of Al mirror surfaces. PMID:24327809

  14. Durability of Metallic Interconnects and Protective Coatings

    SciTech Connect

    Yang, Zhenguo; Stevenson, Jeffry W.

    2009-12-15

    To build up a useful voltage, a number of solid oxide fuel cells (SOFCs) are electrically connected into series in a stack via interconnects, which are placed between adjacent cells. In addition to functioning as a bi-polar electrical connector, the interconnect also acts as a separator plate that separates the fuel at the anode side of one cell from the air at the cathode side on an adjacent cell. During SOFC operation at the high temperatures, the interconnects are thus simultaneously exposed to the oxidizing air at one side and a reducing fuel that can be either hydrogen or hydrocarbon at the other. Besides, they are in contact with adjacent components, such as electrodes or electrical contacts, seals, etc. With steady reduction in SOFC operating temperatures into the low or intermediate range 600-850oC, oxidation resistant alloys are often used to construct interconnects. However, the metallic interconnects may degrade via interactions at their interfaces with surrounding environments or adjacent components, potentially affecting the stability and performance of interconnects and the SOFC stacks. Thus protection layers are applied to metallic interconnects that also intend to mitigate or prevent chromium migration into cells and the cell poisoning. This chapter provides a comprehensive review of materials for metallic interconnects, their degradation and coating protection.

  15. Aerosol chemical vapor deposition of metal oxide films

    DOEpatents

    Ott, K.C.; Kodas, T.T.

    1994-01-11

    A process of preparing a film of a multicomponent metal oxide including: forming an aerosol from a solution comprised of a suitable solvent and at least two precursor compounds capable of volatilizing at temperatures lower than the decomposition temperature of said precursor compounds; passing said aerosol in combination with a suitable oxygen-containing carrier gas into a heated zone, said heated zone having a temperature sufficient to evaporate the solvent and volatilize said precursor compounds; and passing said volatilized precursor compounds against the surface of a substrate, said substrate having a sufficient temperature to decompose said volatilized precursor compounds whereby metal atoms contained within said volatilized precursor compounds are deposited as a metal oxide film upon the substrate is disclosed. In addition, a coated article comprising a multicomponent metal oxide film conforming to the surface of a substrate selected from the group consisting of silicon, magnesium oxide, yttrium-stabilized zirconium oxide, sapphire, or lanthanum gallate, said multicomponent metal oxide film characterized as having a substantially uniform thickness upon said substrate.

  16. Single Wall Carbon Nano Tube Films and Coatings

    NASA Astrophysics Data System (ADS)

    Sreekumar, T. V.; Kumar, Satish; Ericson, Lars M.; Smalley, Richard E.

    2002-03-01

    Purified single wall carbon nano tubes (SWNTs) produced from the high-pressure carbon monoxide (HiPCO) process have been dissolved /dispersed in oleum. These solutions /dispersions were optically homogeneous and have been used to form stand-alone SWNT films. The washed, dried, and heat-treated films are isotropic. The scanning electron micrographs of the film surface shows that the nanotube ropes (or fibrils) of about 20 nm diameters are arranged just like macroscopic fibers in a non-woven fabric. Polarized Raman spectroscopy of the SWNT film confirms the isotropic nature of these films. The films are being characterized for their thermal, mechanical as well electrical properties. Thin nano tube coatings, including optically transparent coatings, have also been made on a variety of substrates such as glass, polyethylene, polystyrene, polypropylene, silicon wafer, as well as stainless steel.

  17. Solid-gel precursor solutions and methods for the fabrication of polymetallicsiloxane coating films

    DOEpatents

    Sugama, Toshifumi (Mastic Beach, NY)

    1992-01-01

    Solutions and preparation methods necessary for the fabrication of metal oxide cross-linked polysiloxane coating films are disclosed. The films are useful in provide heat resistance against oxidation, wear resistance, thermal insulation, and corrosion resistance of substrates. The sol-gel precursor solution comprises a mixture of a monomeric organoalkoxysilane, a metal alkoxide M(OR).sub.n (wherein M is Ti, Zr, Ge or Al; R is CH.sub.3, C.sub.2 H.sub.5 or C.sub.3 H.sub.7 ; and n is 3 or 4), methanol, water, HCl and NaOH. The invention provides a sol-gel solution, and a method of use thereof, which can be applied and processed at low temperatures (i.e., <1000.degree. C.). The substrate can be coated by immersing it in the above mentioned solution at ambient temperature. The substrate is then withdrawn from the solution. Next, the coated substrate is heated for a time sufficient and at a temperature sufficient to yield a solid coating. The coated substrate is then heated for a time sufficient, and temperature sufficient to produce a polymetallicsiloxane coating.

  18. Solid-gel precursor solutions and methods for the fabrication of polymetallicsiloxane coating films

    DOEpatents

    Sugama, Toshifumi (Mastic Beach, NY)

    1993-01-01

    Solutions and preparation methods necessary for the fabrication of metal oxide cross-linked polysiloxane coating films are disclosed. The films are useful in provide heat resistance against oxidation, wear resistance, thermal insulation, and corrosion resistance of substrates. The sol-gel precursor solution comprises a mixture of a monomeric organoalkoxysilane, a metal alkoxide M(OR).sub.n (wherein M is Ti, Zr, Ge or Al; R is CH.sub.3, C.sub.2 H.sub.5 or C.sub.3 H.sub.7 ; and n is 3 or 4), methanol, water, HCl and NaOH. The invention provides a sol-gel solution, and a method of use thereof, which can be applied and processed at low temperatures (i.e., <1000.degree. C.). The substrate can be coated by immersing it in the above mentioned solution at ambient temperature. The substrate is then withdrawn from the solution. Next, the coated substrate is heated for a time sufficient and at a temperature sufficient to yield a solid coating. The coated substrate is then heated for a time sufficient, and temperature sufficient to produce a polymetallicsiloxane coating.

  19. Solid-gel precursor solutions and methods for the fabrication of polymetallicsiloxane coating films

    DOEpatents

    Toshifumi Sugama.

    1993-04-06

    Solutions and preparation methods necessary for the fabrication of metal oxide cross-linked polysiloxane coating films are disclosed. The films are useful in provide heat resistance against oxidation, wear resistance, thermal insulation, and corrosion resistance of substrates. The sol-gel precursor solution comprises a mixture of a monomeric organoalkoxysilane, a metal alkoxide M(OR)[sub n] (wherein M is Ti, Zr, Ge or Al; R is CH[sub 3], C[sub 2]H[sub 5] or C[sub 3]H[sub 7]; and n is 3 or 4), methanol, water, HCl and NaOH. The invention provides a sol-gel solution, and a method of use thereof, which can be applied and processed at low temperatures (i.e., < 1,000 C.). The substrate can be coated by immersing it in the above mentioned solution at ambient temperature. The substrate is then withdrawn from the solution. Next, the coated substrate is heated for a time sufficient and at a temperature sufficient to yield a solid coating. The coated substrate is then heated for a time sufficient, and temperature sufficient to produce a polymetallicsiloxane coating.

  20. Thin film coatings for space electrical power system applications

    SciTech Connect

    Gulino, D.A.

    1988-09-01

    This paper examines some of the ways in which thin film coatings can play a role in aerospace applications. Space systems discussed include photovoltaic and solar dynamic electric power generation systems, including applications in environmental protection, thermal energy storage, and radiator emittance enhancement. Potential applications of diamondlike films to both atmospheric and space based systems are examined. Also, potential uses of thin films of the recently discovered high-temperature superconductive materials are discussed.

  1. Process for coating tungsten carbide with cobalt metal

    SciTech Connect

    Ritsko, J.E.; Lee, J.S.

    1989-01-31

    A process is described for coating tungsten carbide with cobalt metal, the process comprising: (a) forming an aqueous slurry of tungsten carbide having a particle size of no greater than - 100 mesh, and zinc metal powder; (b) adding ammonia to the slurry with the amount of the ammonia being sufficient so that the slurry is basic after the subsequent addition of cobalt chloride in step c; (c) adding to the resulting ammoniated slurry, a solution of cobalt chloride with agitation, to form a coating of partially reduced cobalt on the tungsten carbide; (d) removing the resulting cobalt coated tungsten carbide from the resulting liquor; and (e) heating the cobalt coated tungsten carbide in a reducing atmosphere to effect the essentially complete reduction of the cobalt and to produce a cobalt metal coating on the tungsten carbide, the coating making up no greater than about 15% of weight of the tungsten carbide.

  2. Hydroxyapatite-coated metals: interfacial reactions during sintering.

    PubMed

    Wei, M; Ruys, A J; Swain, M V; Milthorpe, B K; Sorrell, C C

    2005-02-01

    Electrophoretic deposition (EPD) is a low cost flexible process for producing HA coatings on metal implants. Its main limitation is that it requires heating the coated implant in order to densify the HA. HA typically sinters at a temperature below 1150 degrees C, but metal implants are degraded above 1000 degrees C. Further, the metal induces the decomposition of the HA coating upon sintering. Recent developments have enabled EPD of metathesis-synthesised uncalcined HA which sinters at approximately 1000 degrees C. The effects of temperature on HA-coated Ti, Ti6Al4V, and 316L stainless steel were investigated for dual coatings of metathesis HA sintered at 1000 degrees C. The use of dual HA coatings (coat, sinter, coat, sinter) enabled decomposition to be confined to the "undercoat" (HA layer 1), with the surface coating decomposition free. The tensile strength of the three metals was not significantly affected by the high sintering temperatures (925 degrees C < T < 1000 degrees C). XRD/SEM/EDS analyses of the interfacial zones revealed that 316L had a negligible HA:metal interfacial zone (approximately 1 microm) while HA:Ti and HA:Ti6Al4V had large interfacial zones (>10 microm) comprising a TiO2 oxidation zone and a CaTiO2 reaction zone. PMID:15744597

  3. Reflective Self-Metallizing Polyimide Films

    NASA Technical Reports Server (NTRS)

    Thompson, David W. (Inventor); Caplan, Maggie L. (Inventor); St.Clair, Anne (Inventor)

    1997-01-01

    A silver organic complex, such as silver acetate, is solubilized in a polyamic acid resin or soluble polyimide solution using a suitable solvent such as hexafluoroacetyl acetone. The mixture is stable and can be applied to both flat and contoured surfaces. Application can be performed by casting, dip-coating, spraying, or other suitable techniques. In addition, the mixture can be cast or extruded as a polyimide film which is not applied to an underlying substrate. Upon curing, a flexible silver coated polyimide film is produced.

  4. A Nafion-coated bismuth film electrode for the determination of heavy metals in vegetable using differential pulse anodic stripping voltammetry: An alternative to mercury-based electrodes

    Microsoft Academic Search

    He Xu; Liping Zeng; Dekun Huang; Yuezhong Xian; Litong Jin

    2008-01-01

    Mercury electrodes have been traditionally employed for achieving high reproducibility and sensitivity of the stripping technique. However, new alternative electrode materials are highly desired because of the toxicity of mercury. Bismuth is an electrode material characterized by its low toxicity and its ability to form alloys with some metals such as cadmium, lead and zinc, allowing their preconcentration at the

  5. Nano-enabled tribological thin film coatings: global patent scenario.

    PubMed

    Sivudu, Kurva S; Mahajan, Yashwant R; Joshi, Shrikant V

    2014-01-01

    The aim of this paper is to present current status and future prospects of nano-enabled tribological thin film coatings based on worldwide patent landscape analysis. The study also presents an overview of technological trends by carrying out state-of-the-art literature analysis, including survey of corporate websites. Nanostructured tribological coatings encompass a wide spectrum of nanoscale microstructures, including nanocrystalline, nanolayered, nano-multilayered, nanocomposite, nanogradient structures or their unique combinations, which are composed of single or multi-component phases. The distinct microstructural features of the coatings impart outstanding tribological properties combined with multifunctional attributes to the coated components. Their unique combination of remarkable properties make them ideal candidates for a wide range of applications in diverse fields such as cutting and metalworking tools, biomedical devices, automotive engine components, wear parts, hard disc drives etc. The patent landscape analysis has revealed that nano-enabled tribological thin film coatings have significant potential for commercial applications in view of the lion's share of corporate industry in patenting activity. The largest patent portfolio is held by Japan followed by USA, Germany, Sweden and China. The prominent players involved in this field are Mitsubishi Materials Corp., Sandvik Aktiebolag, Hitachi Ltd., Sumitomo Electric Industries Ltd., OC Oerlikon Corp., and so on. The outstanding potential of nanostructured thin film tribological coatings is yet to be fully unravelled and, therefore, immense opportunities are available in future for microstructurally engineered novel coatings to enhance their performance and functionality by many folds. PMID:24962377

  6. Bulk photoemission from metal films and nanoparticles

    NASA Astrophysics Data System (ADS)

    Ikhsanov, R. Sh; Babicheva, V. E.; Protsenko, I. E.; Uskov, A. V.; Guzhva, M. E.

    2015-01-01

    Internal emission of photoelectrons from metal films and nanoparticles (nanowires and nanospheres) into a semiconductor matrix is studied theoretically by taking into account the jump of the effective electron mass at the metal – semiconductor interface and the cooling effect of hot electrons due to electron – electron collisions in the metal. The internal quantum efficiency of photoemission for the film and nanoparticles of two types (nanospheres and nanowires) is calculated. It is shown that the reduction of the effective mass of the electron during its transition from metal to semiconductor may lead to a significant (orders of magnitude and higher) decrease in the internal quantum efficiency of bulk photoemission.

  7. Recycling light metals: Optimal thermal de-coating

    NASA Astrophysics Data System (ADS)

    Kvithyld, Anne; Meskers, C. E. M.; Gaal, Sean; Reuter, Markus; Engh, Thorvald Abel

    2008-08-01

    Thermal de-coating of painted and lacquered scrap is one of the new innovations developed for aluminum recycling. If implemented in all recycling and optimized as suggested in this article, recovery would be improved with considerable economic impact. Generally, contaminated scrap is difficult to recycle. Direct re-melting of coated scrap results in the generation of gaseous emissions, with increased metal oxidation, contamination, and salt flux usage. By thermal de-coating of the scrap these problems are avoided. Thermal de-coating followed by remelting of aluminum scrap is now common practice, while painted magnesium scrap is not currently de-coated and recycled. This article presents observations during heating of the contaminated light metals together with the mass loss, evolved gases, and residue after de-coating in order to give a general description of the de-coating process. It is argued that the main behavior during de-coating may be described as two distinct regimes—scission and combustion—regardless of metal substrate and coating. Monitoring the combustion regime should assure optimum de-coating.

  8. UV lithographic patterning on spin-coated DNA thin-films

    Microsoft Academic Search

    Darnell E. Diggs; James G. Grote; Carrie Bartsch; Fahima Ouchen; Anup Sharma; J. M. Taguenang; Aschalew Kassu; Redahegn Sileshi

    2008-01-01

    Photopatterning with 266 nm UV light was accomplished on spin-coated DNA thin films using two different techniques. Lithographic masks were used to create 10-100 micron-sized arrays of enhanced hydrophilicity. Two such masks were used: (1) Polka Dot Filter having opaque squares and a transparent grid and (2) A metal wire-mesh having transparent squares and opaque grid. UV light selectively photodissociates

  9. Radiation Damage in Nanostructured Metallic Films 

    E-print Network

    Yu, Kaiyuan

    2013-04-15

    with favorable microstructures and to investigate their response to radiation. The goals of this thesis are to study the radiation responses of several nanostructured metallic thin film systems, including Ag/Ni multilayers, nanotwinned Ag and nanocrystalline Fe...

  10. Mechanical and barrier properties of biodegradable soy protein isolate-based films coated with polylactic acid

    Microsoft Academic Search

    Jong-Whan Rhim; Jun Ho Lee; Perry K. W. Ng

    2007-01-01

    Polylactic acid (PLA)-coated soy protein isolate (SPI) films were prepared by dipping SPI film into PLA solution. The effects of coating on improvements in mechanical and water barrier properties of the film were tested by measuring selected film properties such as tensile strength (TS), elongation at break (E), water vapor permeability (WVP), and water solubility (WS). TS of SPI films

  11. Corrosion protection by sonoelectrodeposited organic films on zinc coated steel.

    PubMed

    Et Taouil, Abdeslam; Mahmoud, Mahmoud Mourad; Lallemand, Fabrice; Lallemand, Séverine; Gigandet, Marie-Pierre; Hihn, Jean-Yves

    2012-11-01

    A variety of coatings based on electrosynthesized polypyrrole were deposited on zinc coated steel in presence or absence of ultrasound, and studied in terms of corrosion protection. Cr III and Cr VI commercial passivation were used as references. Depth profiling showed a homogeneous deposit for Cr III, while SEM imaging revealed good surface homogeneity for Cr VI layers. These chromium-based passivations ensured good protection against corrosion. Polypyrrole (PPy) was also electrochemically deposited on zinc coated steel with and without high frequency ultrasound irradiation in aqueous sodium tartrate-molybdate solution. Such PPy coatings act as a physical barrier against corrosive species. PPy electrosynthesized in silent conditions exhibits similar properties to Cr VI passivation with respect to corrosion protection. Ultrasound leads to more compact and more homogeneous surface structures for PPy, as well as to more homogeneous distribution of doping molybdate anions within the film. Far better corrosion protection is exhibited for such sonicated films. PMID:22516111

  12. Surface Plasmons in Thin Metallic Films

    E-print Network

    A. V. Latyshev; A. A. Yushkanov

    2010-10-11

    For the first time it is shown that for thin metallic films thickness of which not exceed thickness of skin -- layer, the problem of description of surface plasma oscillations allows analytical solution by arbitrary ratio between length of electrons free path and thickness of a film. The dependance of frequency surface plasma oscillations on wave number is carry out.

  13. Secondary organic aerosol coating of synthetic metal-oxide nanoparticles.

    PubMed

    Lee, Joohyung; Donahue, Neil M

    2011-06-01

    Secondary organic aerosol (SOA) from the ?-pinene + ozone reaction readily coats TiO(2) and CeO(2) metal-oxide nanoparticles in smog-chamber experiments under atmospherically relevant conditions. Otherwise identical experiments compared bare nanoparticles and nanoparticles coated with poly(acrylic acid) (PAA). The PAA-coated particles result in significantly higher new-particle formation rates, suggesting that the SOA vapors coat bare metal oxide more readily than the PAA. After particles begin to grow via SOA coating, however, all particles, independent of size or the presence of a metal-oxide core, grow with a rate proportional to their surface area, modified to account for gas-phase diffusion in the transition regime between the kinetic and bulk-flow regimes. This suggests that SOA condensational growth may be modeled based on the size distribution of the condensational sink in the atmosphere. PMID:21534558

  14. Improved performance of thin film broadband antireflective coatings

    Microsoft Academic Search

    Matthew Mishrikey; Arya Fallahi; Christian Hafner; Rüdiger Vahldieck

    2007-01-01

    Antireflective coatings are useful for a range of applications, from minimizing the radar cross-section of stealth aircraft, to maximizing the efficiency of solar energy panels. New low-index nanorod thin films promise broadband, broad angle performance for such coatings. We demonstrate that a bandwidth increase from 38.5% to 113% is possible by using a simple evolutionary strategy to optimize the thin

  15. PLD fabrication of ZnO nanostructures on metal-coated substrates

    NASA Astrophysics Data System (ADS)

    Dikovska, A. Og; Koleva, M. E.; Atanasova, G. B.; Stoyanchov, T. R.; Nedyalkov, N. N.; Atanasov, P. A.

    2014-05-01

    In this work, ZnO nanostructures were fabricated on metal (a metal alloy containing Fe, Cr, Mn and Ni) coated silicon substrates by applying pulsed laser deposition. The samples were prepared at substrate temperatures in the range of 550 - 650 °C, oxygen pressure of 5 Pa, and laser fluence <= 1 J cm-2 i.e., process parameters usually used for thin-film deposition. We found that the metal layer's role is substantial in the preparation of nanostructures, the morphology of the catalyst layer determines the growth of the ZnO nanowalls and the increase of the process temperature leads to nanorods formation on the nanowalls.

  16. 21 CFR 520.88g - Amoxicillin trihydrate and clavulanate potassium film-coated tablets.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...trihydrate and clavulanate potassium film-coated tablets. 520.88g Section 520.88g Food and...trihydrate and clavulanate potassium film-coated tablets. (a) Specifications. Each tablet contains amoxicillin trihydrate and...

  17. 21 CFR 520.88g - Amoxicillin trihydrate and clavulanate potassium film-coated tablets.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...trihydrate and clavulanate potassium film-coated tablets. 520.88g Section 520.88g Food and...trihydrate and clavulanate potassium film-coated tablets. (a) Specifications. Each tablet contains amoxicillin trihydrate and...

  18. Metal current collect protected by oxide film

    DOEpatents

    Jacobson, Craig P. (Lafayette, CA); Visco, Steven J. (Berkeley, CA); DeJonghe, Lutgard C. (Lafayette, CA)

    2004-05-25

    Provided are low-cost, mechanically strong, highly electronically conductive current collects and associated structures for solid-state electrochemical devices, techniques for forming these structures, and devices incorporating the structures. The invention provides solid state electrochemical devices having as current interconnects a ferritic steel felt or screen coated with a protective oxide film.

  19. Ion beam sputter-deposited thin film coatings for protection of spacecraft polymers in low earth orbit

    NASA Technical Reports Server (NTRS)

    Banks, B. A.; Mirtich, M. J.; Rutledge, S. K.; Swec, D. M.; Nahra, H. K.

    1985-01-01

    Ion beam sputter-deposited thin films at Al2O3, SiO2, and a codeposited mixture of predominantly SiO2 with small amounts of fluoropolymer were evaluated both in laboratory plasma ashing tests and in space on board Shuttle flight STS-8 for effectiveness in preventing oxidation of polyimide Kapton. Measurements of mass loss and optical performance of coated and uncoated polyimide samples exposed to the low earth orbital environment are presented. Optical techniques were used to measure loss rates of protective films exposed to atomic oxygen. Results of the analysis of the space flight exposed samples indicate that thin film metal oxide coatings are very effective in protecting the polyimide. Metal oxide coatings with a small amount of fluoropolymer codeposited have the additional benefit of great flexibility.

  20. Incorporation of Metallic Nanoparticles into Conducting Polymer Actuator Films

    NASA Astrophysics Data System (ADS)

    Costa, Alexsandro Santos; Li, Kwong-Chi; Kilmartin, Paul A.; Travas-Sejdic, Jadranka

    2009-07-01

    Nanocomposites of conducting polymer films (CP) with metal nanoparticles have been prepared. Electropolymerization of pyrrole on stainless steel electrodes was undertaken galvanostatically until the thickness of the polypyrrole (PPy) film reached around 7.5 ?m, which is suitable for the future application of these films in micropumps and microvalves. Subsequently platinum nanoparticles were deposited from a solution of a platinum precursor (K2PtCl6) onto the PPy coated stainless steel electrodes by applying a potential of -0.1 V for between 3 and 15 s. The length of the deposition time led to significant differences in the morphology and size of the particles obtained. The actuation of the free standing films was studied by electrochemomechanical deformation measurements (ECMD) on strips of films cycled in NaPF6. Depending upon the test conditions, the strain rate and ultimate strain of films containing Pt nanoparticles could be increased by a factor of 2 or more compared to those of pristine PPy films.

  1. Effect of metallic coating properties on the tribology of oil- lubricated coated-ceramics

    SciTech Connect

    Ajayi, O.O.; Fenske, G.R.; Erdemir, A.; Erck, R.A.; Hsieh, J.H.; Nichols, F.A.

    1992-04-01

    The friction and wear behavior of zirconia ceramics lubricated with solid coatings (AG, Au, and Nb), deposited by ion-beam-assisted-deposition (IBAD) techniques, and a polyol-ester-based synthetic oil are presented. These results demonstrate that, although the simultaneous use of soft (e.g. Ag and Au) solid lubricants in conjunction with the synthetic lubricant significantly reduces the friction and wear under boundary lubrication at temperatures up to 250{degree}C, the durability of the soft films was poor. In contrast, durability of Nb coating (in terms of chemical reactivity and adhesion during the tribo-tests) was better than that of the Ag or Au films. However, the friction and wear behavior of the Nb-coated films was poorer than that of the ceramics coated with Ag or Au.

  2. Effect of metallic coating properties on the tribology of oil- lubricated coated-ceramics

    SciTech Connect

    Ajayi, O.O.; Fenske, G.R.; Erdemir, A.; Erck, R.A.; Hsieh, J.H.; Nichols, F.A.

    1992-01-01

    The friction and wear behavior of zirconia ceramics lubricated with solid coatings (AG, Au, and Nb), deposited by ion-beam-assisted-deposition (IBAD) techniques, and a polyol-ester-based synthetic oil are presented. These results demonstrate that, although the simultaneous use of soft (e.g. Ag and Au) solid lubricants in conjunction with the synthetic lubricant significantly reduces the friction and wear under boundary lubrication at temperatures up to 250{degree}C, the durability of the soft films was poor. In contrast, durability of Nb coating (in terms of chemical reactivity and adhesion during the tribo-tests) was better than that of the Ag or Au films. However, the friction and wear behavior of the Nb-coated films was poorer than that of the ceramics coated with Ag or Au.

  3. Modelling the dip coating process for hot metal castings

    E-print Network

    McGuinness, Mark

    Modelling the dip coating process for hot metal castings Mark J. McGuinness #3; A.J. Roberts y . . . . . . . . . . . . . . . 14 5.3 Heat transport modelled by rotation of uidised particles . . 16 5.4 Estimated Thermal Di#11 #12; List of Figures 2 6 Modelling Coating Growth 17 6.1 Simple Conduction Model

  4. Deposition of metallic coatings on polymer surfaces using cold spray

    Microsoft Academic Search

    R. Lupoi; W. O'Neill

    2010-01-01

    Current coating technologies such as plasma spray, High Velocity Oxygen Fuel (HVOF) or laser cladding involve the delivery of molten materials during the deposition process. However, such techniques are not well suited to the deposition of metallic coatings on polymers and composites. Cold spray (CS) has attracted much industrial interest over the past two decades. In this method, a material

  5. Fluoride thin films for reflective coatings at 157 nm

    NASA Astrophysics Data System (ADS)

    Cowell, Ronald L. J.

    1998-05-01

    An overview of the excimer laser market shows the trend towards shorter operating wavelengths. The optical properties of vacuum ultraviolet materials are described and the design of a reflective fluoride multilayer coating for 157 nm is given. Practical considerations and techniques used for the coating manufacture are discussed. Results on coating performance and film properties are presented. Finally, a summary reviews the relevant aspects and salient points encountered during the project with an indication of the direction of any subsequent follow-up work.

  6. Wavelength- and thickness-independent optical coatings for integrated circuit metallization layers

    NASA Astrophysics Data System (ADS)

    Draper, Bruce L.; Mahoney, A. R.; Bailey, G. A.

    1987-12-01

    Detailed measurements have been made of the optical properties of sputtered tantalum silicide films on aluminum layers used in integrated circuit fabrication. This new multicomponent conductor (TaSix on aluminum), which is currently in use because of its exceptional electrical, physical, and chemical properties, was also found to have superior optical properties compared to aluminum alone. The addition of the thin silicide layers reduces both the total hemispherical and diffuse reflectance properties by up to 45% over the 265-800-nm wavelength range with almost no dependence on film thickness. Unlike other optical coatings used on metal layers in integrated circuit manufacturing, the silicide films do not need to be removed after photolithography and pattern transfer processes are completed: aluminum wire bonding from the completed circuit (with silicide coating) to the package is highly reliable and reproducible.

  7. Simple push coating of polymer thin-film transistors

    PubMed Central

    Ikawa, Mitsuhiro; Yamada, Toshikazu; Matsui, Hiroyuki; Minemawari, Hiromi; Tsutsumi, Jun'ya; Horii, Yoshinori; Chikamatsu, Masayuki; Azumi, Reiko; Kumai, Reiji; Hasegawa, Tatsuo

    2012-01-01

    Solution processibility is a unique advantage of organic semiconductors, permitting the low-cost production of flexible electronics under ambient conditions. However, the solution affinity to substrate surfaces remains a serious dilemma; liquid manipulation is more difficult on highly hydrophobic surfaces, but the use of such surfaces is indispensable for improving device characteristics. Here we demonstrate a simple technique, which we call ‘push coating’, to produce uniform large-area semiconducting polymer films over a hydrophobic surface with eliminating material loss. We utilize a poly(dimethylsiloxane)-based trilayer stamp whose conformal contact with the substrate enables capillarity-induced wetting of the surface. Films are formed through solvent sorption and retention in the stamp, allowing the stamp to be peeled perfectly from the film. The planar film formation on hydrophobic surfaces also enables subsequent fine film patterning. The technique improves the crystallinity and field-effect mobility of stamped semiconductor films, constituting a major step towards flexible electronics production. PMID:23132026

  8. Evaluation of colorless polyimide film for thermal control coating applications

    NASA Technical Reports Server (NTRS)

    St.clair, A. K.; Slemp, W. S.

    1985-01-01

    A series of essentially colorless aromatic polyimide films was synthesized and characterized with the objective of obtaining maximum optical transparency for applications in space. Optical transparency is a requirement for high performance polymeric films used in second surface mirror coatings on thermal control systems. The intensity in color of aromatic polyimide films was lowered by reducing the electronic interaction between chromophoric centers in the polymer molecular structure and by using highly purified monomers. The resulting lightly colored to colorless polyimide films were characterized by UV-visible and infrared spectroscopy before and after exposure to 300 equivalent solar hours UV irradiation and varying doses of 1 MeV electron irradiation. After irradiation, the films were found to be 2 to 2.5 times more transparent than commercial polyimide film of the same thickness.

  9. Electrical properties of nanoscale metallic thin films on dielectric elastomer at various strain rates

    NASA Astrophysics Data System (ADS)

    Faisal, Md. Shahnewaz Sabit; Ye, Zhihang; Chen, Zheng; Asmatulu, Ramazan

    2015-04-01

    Dielectric elastomers (DEs) have significant applications in artificial muscle and other biomedical equipment and device fabrications. Metallic thin films by thin film transfer and sputter coating techniques can provide conductive surfaces on the DE samples, and can be used as electrodes for the actuators and other biomedical sensing devices. In the present study, 3M VHB 4910 tape was used as a DE for the coating and electrical characterization tests. A 150 nm thickness of gold was coated on the DE surfaces by sputter coating under vacuum with different pre-strains, ranging from 0 to 100%. Some of the thin films were transferred to the surface of the DEs. Sputter coating, and direct transferring gold leaf coating methods were studied and the results were analyzed in detail in terms of the strain rates and electrical resistivity changes. Initial studies indicated that the metallic surfaces remain conductive even though the DE films were considerably elongated. The coated DEs can be used as artificial muscle by applying electrical stimulation through the conductive surfaces. This study may provide great benefits to the readers, researchers, as well as companies involved in manufacturing of artificial muscles and actuators using smart materials.

  10. Method for improving the oxidation-resistance of metal substrates coated with thermal barrier coatings

    DOEpatents

    Thompson, Anthony Mark (Niskayuna, NY); Gray, Dennis Michael (Delanson, NY); Jackson, Melvin Robert (Niskayuna, NY)

    2002-01-01

    A method for providing a protective coating on a metal-based substrate is disclosed. The method involves the application of an aluminum-rich mixture to the substrate to form a discontinuous layer of aluminum-rich particles, followed by the application of a second coating over the discontinuous layer of aluminum-rich particles. Aluminum diffuses from the aluminum-rich layer into the substrate, and into any bond coat layer which is subsequently applied. Related articles are also described.

  11. Ion assisted deposition of optical and protective coatings for heavy metal fluoride glass

    Microsoft Academic Search

    James J. McNally; Ghanim A. Al-Jumaily; John R. McNeil; B. Bendow

    1986-01-01

    Heavy metal fluoride glass materials are attractive for optical applications in the near UV through IR wavelength regions. However, many compositions are relatively soft and hygroscopic and possess low softening temperature (250--300°C). We have applied ion assisted deposition (IAD) techniques to deposit MgFâ, SiOâ, and AlâOâ\\/SiOâ thin film structures on fluoride glass substrates at ambient substrate temperature (--100°C). The coatings

  12. Polymer-Mercury Coated Screen-Printed Sensors for Electrochemical Stripping Analysis of Heavy Metals

    Microsoft Academic Search

    Ilaria Palchetti; Sanaa Majid; Alessandra Kicela; Giovanna Marrazza; Marco Mascini

    2003-01-01

    In the perspective of in-field stripping analysis of heavy metals, the use and disposal of toxic mercury solutions (necessary to plate a mercury film on a carbon electrode surface) presents a problem. The aim of this work was the development of mercury coated screen-printed electrodes previously prepared in the lab and ready to use in-field. Thus some commercially available polymers

  13. Protective lithium ion conducting ceramic coating for lithium metal anodes and associate method

    DOEpatents

    Bates, John B. (Oak Ridge, TN)

    1994-01-01

    A battery structure including a cathode, a lithium metal anode and an electrolyte disposed between the lithium anode and the cathode utilizes a thin-film layer of lithium phosphorus oxynitride overlying so as to coat the lithium anode and thereby separate the lithium anode from the electrolyte. If desired, a preliminary layer of lithium nitride may be coated upon the lithium anode before the lithium phosphorous oxynitride is, in turn, coated upon the lithium anode so that the separation of the anode and the electrolyte is further enhanced. By coating the lithium anode with this material lay-up, the life of the battery is lengthened and the performance of the battery is enhanced.

  14. Low Temperature Growth of Nanostructured Diamond Films on Metals

    NASA Technical Reports Server (NTRS)

    Baker, Paul A.; Catledge, Shane A.; Vohra, Yogesh K.

    2001-01-01

    The field of nanocrystalline diamond and tetrahedral amorphous carbon films has been the focus of intense experimental activity in the last few years for applications in field emission display devices, optical windows, and tribological coatings, The choice of substrate used in most studies has typically been silicon. For metals, however, the thermal expansion mismatch between the diamond film and substrate gives rise to thermal stress that often results in delamination of the film. To avoid this problem in conventional CVD deposition low substrate temperatures (less than 700 C) have been used, often with the incorporation of oxygen or carbon monoxide to the feedgas mixture. Conventionally grown CVD diamond films are also rough and would require post-deposition polishing for most applications. Therefore, there is an obvious need to develop techniques for deposition of well-adhered, smooth nano-structured diamond films on metals for various tribological applications. In our work, nanostructured diamond films are grown on a titanium alloy substrate using a two-step deposition process. The first step is performed at elevated temperature (820 C) for 30 minutes using a H2/CH4/N2 gas mixture in order to grow a thin (approx. 600 nm) nanostructured diamond layer and improve film adhesion. The remainder of the deposition involves growth at low temperature (less than 600 C) in a H2/CH4/O2 gas mixture. Laser reflectance Interferometry (LRI) pattern during growth of a nanostructured diamond film on Ti-6Al-4V alloy. The first 30 minutes are at a high temperature of 820 C and the rest of the film is grown at a low temperature of 580 T. The fringe pattern is observed till the very end due to extremely low surface roughness of 40 nm. The continuation of the smooth nanostructured diamond film growth during low temperature deposition is confirmed by in-situ laser reflectance interferometry and by post-deposition micro-Raman spectroscopy and surface profilometry. Similar experiments performed without the starting nanostructured diamond layer resulted in poorly adhered films with a more crystalline appearance and a higher surface roughness. This low temperature deposition of nanostructured diamond films on metals offers advantages in cases where high residual thermal stress leads to delamination at high temperatures.

  15. Thermal fatigue testing of thin metal films

    NASA Astrophysics Data System (ADS)

    Mönig, R.; Keller, R. R.; Volkert, C. A.

    2004-11-01

    An experimental method is described for performing thermal fatigue testing of thin films and lines on substrates. The method uses Joule heating from alternating currents to generate temperature, strain, and stress cycles in the metal structures. The apparatus has been installed in a scanning electron microscope and allows in situ observations of the fatigue damage evolution. First observations on Cu films reveal that fatigue damage forms in submicrometer thick films and is strongly affected by the film thickness and grain size. In addition, results from a special test structure confirm that the damage is caused by fatigue and not by electromigration.

  16. On the use of ceramic PVD coatings to replace metallic coatings in electrical contacts

    Microsoft Academic Search

    Åsa Kassman Rudolphi; Staffan Jacobson

    1997-01-01

    In electrical contacts the combination of high normal pressures and soft contact materials results in large contact areas and low contact resistance, but also in massive plastic deformation and wear. This paper examines some of the potential advantages and disadvantages of replacing one of the soft metallic coatings in electrical power connectors with a hard ceramic coating. Three ceramic PVD

  17. Parametric Study of Metal/Polymer Multilayer Coatings for Temperature Wrinkling Prediction

    NASA Astrophysics Data System (ADS)

    Zhang, Lihong; Habraken, Anne Marie; Ben Bettaieb, Amine; Duchêne, Laurent

    2013-09-01

    This article presents an analytic model for the prediction of wrinkling occurring in metal/polymer coatings under particular conditions. Owing to different thermal expansion coefficients (TECs) of the substrate and the different coating layers, temperature variation can induce a compressive stress in the coating. The wrinkling is the material response to the instability caused by this compressive stress. In this study, a reference case was selected: a 0.27-mm-thick steel sheet with a 5-?m-thick polymer layer and, on top of it, a thin aluminum film of 50 nm in thickness. For this reference case, it was observed and predicted by the model that an increase in temperature yielded to the wrinkling of the thin aluminum film. The geometry of the multilayer coating and the properties of the constituent materials are factors able to promote or prevent the wrinkle. To better understand and predict their effects, a sensitivity analysis was carried out with the proposed analytic model. A special attention was devoted to the temperature when wrinkling occurs. The key parameters having a significant influence on the wrinkling temperature were identified. It is concluded that the elastic modulus of the thin aluminum film and that of the polymer, the TEC of the thin film, and the initial stress induced during the processing of the multilayer system all had a significant influence on the wrinkling temperature.

  18. Soap-film coating: High-speed deposition of multilayer nanofilms

    PubMed Central

    Zhang, Renyun; Andersson, Henrik A.; Andersson, Mattias; Andres, Britta; Edlund, Håkan; Edström, Per; Edvardsson, Sverker; Forsberg, Sven; Hummelgård, Magnus; Johansson, Niklas; Karlsson, Kristoffer; Nilsson, Hans-Erik; Norgren, Magnus; Olsen, Martin; Uesaka, Tetsu; Öhlund, Thomas; Olin, Håkan

    2013-01-01

    The coating of thin films is applied in numerous fields and many methods are employed for the deposition of these films. Some coating techniques may deposit films at high speed; for example, ordinary printing paper is coated with micrometre-thick layers of clay at a speed of tens of meters per second. However, to coat nanometre thin films at high speed, vacuum techniques are typically required, which increases the complexity of the process. Here, we report a simple wet chemical method for the high-speed coating of films with thicknesses at the nanometre level. This soap-film coating technique is based on forcing a substrate through a soap film that contains nanomaterials. Molecules and nanomaterials can be deposited at a thickness ranging from less than a monolayer to several layers at speeds up to meters per second. We believe that the soap-film coating method is potentially important for industrial-scale nanotechnology. PMID:23503102

  19. Recycled hard metal-base wear-resistant composite coatings

    Microsoft Academic Search

    P. Kulu; J. Halling

    1998-01-01

    The abrasion-erosion wear resistance of composite coatings from self-fluxing Ni-base alloy and WC-Co hard metal powders is\\u000a evaluated. The resistance of thermal sprayed and melted NiCrSiB-(WC-Co) coatings was found to be markedly higher than that\\u000a of NiCrSiB and slightly higher than that of comparative welded coatings. Microstructural and surface analyses were used to\\u000a describe the coatings and the wear damage.

  20. THE PENETRABILITY OF A THIN METALLIC FILM INSIDE THE RF FIELD.

    SciTech Connect

    ZHAO, Y.; BEN-ZVI, I.; CHANG, X.; RAO, T.; CHEN, W.; DINARDO, R.; BEUTENMULLER, R.

    2005-05-16

    Thin metallic film was widely applied in various areas. Especially, recently we are planning to apply it in a ''Secondary emission enhanced photo-injector'', in which a diamond cathode is coated with a metallic film on its back to serve as a current path. The thickness of the film is originally considered to be in the order of 10 nm, which is much less than the skin depth, by a factor of almost 200. One would think intuitively that the RF filed would penetrate such a thin film. However, we found it is not true. The film will block most of the field. This paper addresses theoretical analysis as well as the experimental results, and demonstrates that the penetrability of a thin film is very poor. Consequently, most of the RF current will flow on the thin film causing a serious heating problem.

  1. Interfacial bond strength of electrophoretically deposited hydroxyapatite coatings on metals.

    PubMed

    Wei, M; Ruys, A J; Swain, M V; Kim, S H; Milthorpe, B K; Sorrell, C C

    1999-07-01

    Hydroxyapatite (HAp) coatings were deposited onto substrates of metal biomaterials (Ti, Ti6Al4V, and 316L stainless steel) by electrophoretic deposition (EPD). Only ultra-high surface area HAp powder, prepared by the metathesis method 10Ca(NO3)2 + 6(NH4)2HPO4 + 8NH4OH), could produce dense coatings when sintered at 875-1000degreesC. Single EPD coatings cracked during sintering owing to the 15-18% sintering shrinkage, but the HAp did not decompose. The use of dual coatings (coat, sinter, coat, sinter) resolved the cracking problem. Scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) inspection revealed that the second coating filled in the "valleys" in the cracks of the first coating. The interfacial shear strength of the dual coatings was found, by ASTM F1044-87, to be approximately 12 MPa on a titanium substrate and approximately 22 MPa on 316L stainless steel, comparing quite favorably with the 34 MPa benchmark (the shear strength of bovine cortical bone was found to be 34 MPa). Stainless steel gave the better result since -316L (20.5 microm mK(-1)) > alpha-HAp (approximately 14 microm mK(-1)), resulting in residual compressive stresses in the coating, whereas alpha-titanium (approximately 10.3 microm mK(-1)) < alpha-HAp, resulting in residual tensile stresses in the coating. PMID:15348125

  2. Characteristics of sol–gel dip coated Ceria films

    Microsoft Academic Search

    K. R. Murali

    2008-01-01

    Cerium oxide(CeO2) thin films were deposited by the sol–gel dip coating technique using cerium chloride, acrylamide and N,N bis methylene acrylamide. The as deposited films were heat-treated at different temperatures in air. X-ray diffraction studies\\u000a indicated the films to be of single phase CeO2. Optical bandgap in the range of 3.53–3.60 eV was obtained from optical studies. Laser Raman studies exhibited

  3. Coatings and films made of silk proteins.

    PubMed

    Borkner, Christian B; Elsner, Martina B; Scheibel, Thomas

    2014-09-24

    Silks are a class of proteinaceous materials produced by arthropods for various purposes. Spider dragline silk is known for its outstanding mechanical properties, and it shows high biocompatibility, good biodegradability, and a lack of immunogenicity and allergenicity. The silk produced by the mulberry silkworm B. mori has been used as a textile fiber and in medical devices for a long time. Here, recent progress in the processing of different silk materials into highly tailored isotropic and anisotropic coatings for biomedical applications such as tissue engineering, cell adhesion, and implant coatings as well as for optics and biosensors is reviewed. PMID:25004395

  4. Synergistic Fire Performance Between Metal or Metal Filled Organic Coatings and Engineering Plastics

    Microsoft Academic Search

    Ramazan Benrashid; Gordon L. Nelson

    1993-01-01

    Metal filled organic and EMI coatings affect the fire performance properties of engineering plastics. Zinc arc spray, zinc\\/epoxy, and zinc borate\\/epoxy coatings on modified-polyphenylene oxide (m-PPO) are particu larly effective. The results from non-flaming NBS smoke chamber tests show a dramatic reduction in smoke for zinc and zinc borate coatings, whereas a ZnO coating did not show the same effect.

  5. Stresses in thin film metallization

    Microsoft Academic Search

    Thomas C. Hodge; Sue Ann Bidstrup-Allen; Paul A. Kohl

    1997-01-01

    Stresses in conductors used in microelectronic interconnections are a critical processing and reliability issue. This work examines: 1) the temperature-dependent stress behavior of sputtered and electroplated silver and gold films on silicon substrates; 2) the use of wafer curvature using multiple substrates for the simultaneous determination of coefficient of thermal expansion (CTE) and modulus for thin films. The stress-temperature behavior

  6. Nanostructured thin films as functional coatings

    NASA Astrophysics Data System (ADS)

    Lazar, Manoj A.; Tadvani, Jalil K.; Sze Tung, Wing; Lopez, Lorena; Daoud, Walid A.

    2010-06-01

    Nanostructured thin films is one of the highly exploiting research areas particularly in applications such as photovoltaics, photocatalysis and sensor technologies. Highly tuned thin films, in terms of thickness, crystallinity, porosity and optical properties, can be fabricated on different substrates using the sol-gel method, chemical solution deposition (CSD), electrochemical etching, along with other conventional methods such as chemical vapour deposition (CVD) and physical vapour deposition (PVD). The above mentioned properties of these films are usually characterised using surface analysis techniques such as XRD, SEM, TEM, AFM, ellipsometry, electrochemistry, SAXS, reflectance spectroscopy, STM, XPS, SIMS, ESCA, X-ray topography and DOSY-NMR. This article presents a short review of the preparation and characterisation of thin films of nanocrystalline titanium dioxide and modified silicon as well as their application in solar cells, water treatment, water splitting, self cleaning fabrics, sensors, optoelectronic devices and lab on chip systems.

  7. Magnetoelastic sensor for characterizing properties of thin-film/coatings

    NASA Technical Reports Server (NTRS)

    Bachas, Leonidas G. (Inventor); Barrett, Gary (Inventor); Grimes, Craig A. (Inventor); Kouzoudis, Dimitris (Inventor); Schmidt, Stefan (Inventor)

    2004-01-01

    An apparatus for determining elasticity characteristics of a thin-film layer. The apparatus comprises a sensor element having a base magnetostrictive element at least one surface of which is at least partially coated with the thin-film layer. The thin-film layer may be of a variety of materials (having a synthetic and/or bio-component) in a state or form capable of being deposited, manually or otherwise, on the base element surface, such as by way of eye-dropper, melting, dripping, brushing, sputtering, spraying, etching, evaporation, dip-coating, laminating, etc. Among suitable thin-film layers for the sensor element of the invention are fluent bio-substances, thin-film deposits used in manufacturing processes, polymeric coatings, paint, an adhesive, and so on. A receiver, preferably remotely located, is used to measure a plurality of values for magneto-elastic emission intensity of the sensor element in either characterization: (a) the measure of the plurality of values is used to identify a magneto-elastic resonant frequency value for the sensor element; and (b) the measure of the plurality of successive values is done at a preselected magneto-elastic frequency.

  8. THz surface wave collapse on coated metal Mufei Gong1

    E-print Network

    Oklahoma State University

    - dependent absorption coefficient, phase velocity, group velocity and group velocity dispersion have beenTHz surface wave collapse on coated metal surfaces Mufei Gong1 , Tae-In Jeon2 and D. Grischkowsky1-791 Korea *daniel.grischkowsky@okstate.edu Abstract: The Zenneck THz surface wave (Z-TSW) on metals

  9. Evaluating the effect of coating equipment on tablet film quality using terahertz pulsed imaging.

    PubMed

    Haaser, Miriam; Naelapää, Kaisa; Gordon, Keith C; Pepper, Michael; Rantanen, Jukka; Strachan, Clare J; Taday, Philip F; Zeitler, J Axel; Rades, Thomas

    2013-11-01

    In this study, terahertz pulsed imaging (TPI) was employed to investigate the effect of the coating equipment (fluid bed and drum coater) on the structure of the applied film coating and subsequent dissolution behaviour. Six tablets from every batch coated with the same delayed release coating formulation under recommended process conditions (provided by the coating polymer supplier) were mapped individually to evaluate the effect of coating device on critical coating characteristics (coating thickness, surface morphology and density). Although the traditional coating quality parameter (weight gain) indicated no differences between both batches, TPI analysis revealed a lower mean coating thickness (CT) for tablets coated in the drum coater compared to fluid bed coated tablets (p<0.05). Moreover, drum coated tablets showed a more pronounced CT variation between the two sides and the centre band of the biconvex tablets, with the CT around the centre band being 22.5% thinner than the top and bottom sides for the drum coated tablets and 12.5% thinner for fluid bed coated tablets. The TPI analysis suggested a denser coating for the drum coated tablets. Dissolution testing confirmed that the film coating density was the drug release governing factor, with faster drug release for tablets coated in the fluid bed coater (98 ± 4% after 6h) compared to drum coated tablets (72 ± 6% after 6h). Overall, TPI investigation revealed substantial differences in the applied film coating quality between tablets coated in the two coaters, which in turn correlated with the subsequent dissolution performance. PMID:23563103

  10. Preparation of PZT ferroelectric thick films by nanopowder-metal-organic decomposition process

    Microsoft Academic Search

    Kuo-shung Liu; Yai-yei Huang; Wen-jiun Lin; Tsang-lan Lin; I-nan Lin

    2000-01-01

    In this paper, a modified metal-organic decomposition (MOD) process has been developed for the fabrication of PZT thick films. Nano-sized PZT powders, around 5–15 nm, were first synthesized using hydrolysis of PZT alkoxide precursors, and then incorporated into a precursor containing PZT-carboxylates (0.2 M), followed by spin-coating process. The properties of nano-powder incorporated PZT precursors solution influences the spin-coating characteristics

  11. On the manufacture of very thin elastomeric films by spin-coating

    E-print Network

    Krishnan, Sriram, 1978 May-

    2007-01-01

    I present a process for manufacturing poly-dimethylsiloxane (PDMS) films of thicknesses down to 50 microns. PDMS films are currently fabricated by spin-coating the polymer on a wafer and then manually peeling the film after ...

  12. UV lithographic patterning on spin-coated DNA thin-films

    NASA Astrophysics Data System (ADS)

    Diggs, Darnell E.; Grote, James G.; Bartsch, Carrie; Ouchen, Fahima; Sharma, Anup; Taguenang, J. M.; Kassu, Aschalew; Sileshi, Redahegn

    2008-08-01

    Photopatterning with 266 nm UV light was accomplished on spin-coated DNA thin films using two different techniques. Lithographic masks were used to create 10-100 micron-sized arrays of enhanced hydrophilicity. Two such masks were used: (1) Polka Dot Filter having opaque squares and a transparent grid and (2) A metal wire-mesh having transparent squares and opaque grid. UV light selectively photodissociates the DNA film where it is exposed into smaller more hydrophilic fragments. UV-exposed films are then coated with a solution of a protein. The protein appears to selectively coat over areas exposed to UV light. We have also used interferometric lithography with UV light to accomplish patterning on the scale of 1 micron on DNA thin films. This technique has the potential to generate micro/nano arrays and vary the array-size. This paper describes the fabrication of these microarrays and a plausible application for fabricating antibody arrays for protein sensing applications.

  13. Molecular insights into shellac film coats from different aqueous shellac salt solutions and effect on disintegration of enteric-coated soft gelatin capsules.

    PubMed

    Al-Gousous, J; Penning, M; Langguth, P

    2015-04-30

    The purpose of this investigation was to study the effect of using different salts of shellac on the disintegration properties of shellac-based enteric coatings. In the last two decades, shellac has been increasingly used as an aqueous solution for enteric coating purposes, with the ammonium salt being the form typically used. Little investigation has been performed on using other salts, and therefore, this was the focus of our work. Enteric coatings, based on different shellac salts (ammonium, sodium, potassium and composite ammonium-sodium), were applied onto soft gelatin capsules. Disintegration testing of the coated soft gelatin capsules showed that alkali metal salts promote faster disintegration than ammonium salts. In order to determine the causes behind these differences, the solubility, thermal and spectroscopic properties of films cast from the different salts were investigated. The results show that films cast from ammonium-based salts of shellac are, unlike those cast from alkali metal-based salts, water-insoluble. Spectroscopic evidence suggests that this might be due to partial salt dissociation resulting in loss of ammonium as ammonia and reduced degree of shellac ionization during drying. In addition, oxidation of shellac aldehyde groups of the ammonium-based shellac salts could also play a role. And possible higher extent of shellac hydrolysis during the preparation of alkali metal salts might also be a factor. Therefore, the nature of the shellac salt used in the preparation of shellac-based aqueous coating solutions is a significant formulation factor affecting product performance. PMID:25578368

  14. Metal-doped magnetite thin films.

    PubMed

    Abe, Seishi; Ping, De Hai; Nakamura, Shintaro; Ohnuma, Masato; Ohnuma, Shigehiro

    2012-06-01

    This paper investigates magnetite (Fe3O4) thin film containing a small amount of a metal element. The films are prepared by rf sputtering with a composite target of ceramic iron oxide with metal chips. Low-temperature magnetization of magnetite containing 5.3%Ge reveals that the film contains some magnetically weak coupling grains. The metal element Mg reduces both hematite (alpha-Fe2O3) and magnetite, resulting in single-phase wüstite (Fe1-xO). In contrast, adding Ge selectively reduces hematite, while magnetite remains unreactive. According to the free energy of reaction, the element Ge is able to reduce hematite only, whereas the element Mg is capable of reducing both hematite and magnetite. This property is in good agreement with the experiment results. PMID:22905582

  15. Metallic and ceramic thin film thermocouples for gas turbine engines.

    PubMed

    Tougas, Ian M; Amani, Matin; Gregory, Otto J

    2013-01-01

    Temperatures of hot section components in today's gas turbine engines reach as high as 1,500 °C, making in situ monitoring of the severe temperature gradients within the engine rather difficult. Therefore, there is a need to develop instrumentation (i.e., thermocouples and strain gauges) for these turbine engines that can survive these harsh environments. Refractory metal and ceramic thin film thermocouples are well suited for this task since they have excellent chemical and electrical stability at high temperatures in oxidizing atmospheres, they are compatible with thermal barrier coatings commonly employed in today's engines, they have greater sensitivity than conventional wire thermocouples, and they are non-invasive to combustion aerodynamics in the engine. Thin film thermocouples based on platinum:palladium and indium oxynitride:indium tin oxynitride as well as their oxide counterparts have been developed for this purpose and have proven to be more stable than conventional type-S and type-K thin film thermocouples. The metallic and ceramic thin film thermocouples described within this paper exhibited remarkable stability and drift rates similar to bulk (wire) thermocouples. PMID:24217356

  16. Immersion Deposition of Metal Films on Silicon and Germanium Substrates in Supercritical Carbon Dioxide

    SciTech Connect

    Ye, Xiang-Rong; Wai, Chien M.; Zhang, Daqing; Kranov, Yanko; Mcilroy, David; Lin, Yuehe; Engelhard, Mark H.

    2003-01-29

    A low temperature carbon dioxide based on immersion deposition technology (SFID) has been developed for producing palladium, copper, silver, and other metal films on silicon-based substrates in supercritical CO2. The reaction is initiated by oxidation of elemental silicon to SiF4 or H2SiF6 by HF with the release of electrons that cause the reduction of metal ions in an organometallic precursor to the metallic form on silicon surface in CO2. Only the substrate surfaces are coated with metals using this method. Based on surface analysis of the films and spectroscopic analysis of the reaction products, the mechanism of metal film deposition is discussed. The metal films (Pd, Cu, and Ag) formed on silicon surfaces by the SFID method exhibit good coverage, smooth and dense texture, high purity and a metallic behavior. Similarly, metal films can also be deposited onto geranium substrates using SFID. The gas-like properties and the high pressure of the supercritical fluids, combined with the low reaction temperature, make this SFID method potentially useful for depositing thin metal films in small features, which are difficult to accomplish by conventional CVD methods.

  17. Effect of target material on deposition and properties of metal-containing DLC (Me-DLC) coatings

    Microsoft Academic Search

    K Bewilogua; C. V Cooper; C Specht; J Schröder; R Wittorf; M Grischke

    2000-01-01

    Metal containing diamond-like carbon (Me-DLC) coatings were prepared by magnetron sputter deposition using tungsten, tungsten carbide, niobium and titanium as target materials. An essential parameter for the process characterization is the target voltage. The substrate heating during the film growth depends on the target material. For the tungsten target, the contribution of energetic neutrals to the heat flux is quite

  18. Development of technique for AR coating and nickel and copper metallization of solar cells. FPS Project: Product development

    Microsoft Academic Search

    W. Taylor

    1982-01-01

    Printed nickel overplated with copper and applied on top of a predeposited silicon nitride antireflective coating system for metallizing solar cells was analyzed. The ESL D and E paste formulations, and the new formulations F, G, H, and D-1 were evaluated. The nickel thick films were tested after firing for stability in the cleaning and plating solutions used in the

  19. Amorphous transition metal oxide films

    Microsoft Academic Search

    Neil Heiman; N. S. Kazama

    1979-01-01

    We have been able to prepare amorphous oxides of Fe and Cr by sputter deposition. Magnetization measurements were made between 4.2 K and 300 K. Mössbauer spectra were obtained for the iron oxide samples in the same temperature range. Amorphous CrO2 films showed no evidence of magnetic order. For the amorphous Fe oxide films, the 4.2 K Mössbauer spectrum showed

  20. Spin Coated Plasmonic Nanoparticle Interfaces for Photocurrent Enhancement in Thin Film Si Solar Cells

    E-print Network

    Israelowitz, Miriam; Cong, Tao; Sureshkumar, Radhakrishna

    2013-01-01

    Nanoparticle (NP) arrays of noble metals strongly absorb light in the visible to infrared wavelengths through resonant interactions between the incident electromagnetic field and the metal's free electron plasma. Such plasmonic interfaces enhance light absorption and photocurrent in solar cells. We report a cost effective and scalable room temperature/pressure spin-coating route to fabricate broadband plasmonic interfaces consisting of silver NPs. The NP interface yields photocurrent enhancement (PE) in thin film silicon devices by up to 200% which is significantly greater than previously reported values. For coatings produced from Ag nanoink containing particles with average diameter of 40 nm, an optimal NP surface coverage of 7% was observed. Scanning electron microscopy of interface morphologies revealed that for low surface coverage, particles are well-separated, resulting in broadband PE. At higher surface coverage, formation of particle strings and clusters caused red-shifting of the PE peak and a narro...

  1. Skylab D024 thermal control coatings and polymeric films experiment

    NASA Technical Reports Server (NTRS)

    Lehn, William L.; Hurley, Charles J.

    1992-01-01

    The Skylab D024 Thermal Control Coatings and Polymeric Films Experiment was designed to determine the effects of the external Skylab space environment on the performance and properties of a wide variety of selected thermal control coatings and polymeric films. Three duplicate sets of thermal control coatings and polymeric films were exposed to the Skylab space environment for varying periods of time during the mission. The specimens were retrieved by the astronauts during extravehicular activities (EVA) and placed in hermetically sealed return containers, recovered, and returned to the Wright Laboratory/Materials Laboratory/WPAFB, Ohio for analysis and evaluation. Postflight analysis of the three sets of recovered thermal control coatings indicated that measured changes in specimen thermo-optical properties were due to a combination of excessive contamination and solar degradation of the contaminant layer. The degree of degradation experienced over-rode, obscured, and compromised the measurement of the degradation of the substrate coatings themselves. Results of the analysis of the effects of exposure on the polymeric films and the contamination observed are also presented. The D024 results were used in the design of the LDEF M0003-5 Thermal Control Materials Experiment. The results are presented here to call to the attention of the many other LDEF experimenters the wealth of directly related, low earth orbit, space environmental exposure data that is available from the ten or more separate experiments that were conducted during the Skylab mission. Results of these experiments offer data on the results of low altitude space exposure on materials recovered from space with exposure longer than typical STS experiments for comparison with the LDEF results.

  2. Ablation of transition metal oxides by different laser pulse duration and thin films deposition

    Microsoft Academic Search

    A. Giardini Guidoni; C Flamini; F Varsano; M Ricci; R Teghil; V Marotta; T. M Di Palma

    2000-01-01

    Thin films of transition metal oxides are of interest in many applications such as anticorrosion coatings and optical and electrochromic devices. In this work, the effect of different wavelength and pulse duration on ablation of oxides target has been investigated. The plume has been characterized by mass spectrometry and optical spectroscopy. Ablation thresholds have been measured by detecting ion emission

  3. Nanomechanical and nanotribological characterization of noble metal-coated AFM tips for probe-based ferroelectric data recording.

    PubMed

    Palacio, Manuel; Bhushan, Bharat

    2008-03-12

    Probe-based data recording is being developed as an alternative technology for ultrahigh areal density. In ferroelectric data storage, a conductive atomic force microscope (AFM) probe with a noble metal coating is placed in contact on lead zirconate titanate (PZT) film, which serves as the ferroelectric material. A crucial mechanical reliability concern is tip wear during contact of the ferroelectric material with the probe. To achieve high wear resistance, the mechanical properties (such as elastic modulus and hardness) of the metal-coated probe should be high. Nanoindentation experiments were performed in order to evaluate the mechanical properties of four commercial noble metal coatings, namely, Pt, Pt-Ni, Au-Ni and Pt-Ir, deposited on AFM probes. The effective hardness and elastic modulus were evaluated, using a contact mechanics model that accounts for the effect of the underlying silicon substrate. The Pt-Ir coating was found to exhibit the highest hardness, highest elastic modulus and lowest creep resistance. Nanoscratch studies reveal that the noble metal coatings are removed primarily by plastic deformation. The Pt-Ir and Pt coatings show the highest and lowest scratch resistance, respectively, which is consistent with results obtained from wear tests of the noble metal-coated AFM probes on a PZT surface. PMID:21817713

  4. Nanomechanical and nanotribological characterization of noble metal-coated AFM tips for probe-based ferroelectric data recording

    NASA Astrophysics Data System (ADS)

    Palacio, Manuel; Bhushan, Bharat

    2008-03-01

    Probe-based data recording is being developed as an alternative technology for ultrahigh areal density. In ferroelectric data storage, a conductive atomic force microscope (AFM) probe with a noble metal coating is placed in contact on lead zirconate titanate (PZT) film, which serves as the ferroelectric material. A crucial mechanical reliability concern is tip wear during contact of the ferroelectric material with the probe. To achieve high wear resistance, the mechanical properties (such as elastic modulus and hardness) of the metal-coated probe should be high. Nanoindentation experiments were performed in order to evaluate the mechanical properties of four commercial noble metal coatings, namely, Pt, Pt-Ni, Au-Ni and Pt-Ir, deposited on AFM probes. The effective hardness and elastic modulus were evaluated, using a contact mechanics model that accounts for the effect of the underlying silicon substrate. The Pt-Ir coating was found to exhibit the highest hardness, highest elastic modulus and lowest creep resistance. Nanoscratch studies reveal that the noble metal coatings are removed primarily by plastic deformation. The Pt-Ir and Pt coatings show the highest and lowest scratch resistance, respectively, which is consistent with results obtained from wear tests of the noble metal-coated AFM probes on a PZT surface.

  5. Dynamics of discontinuous coating and drying of nanoparticulate films.

    SciTech Connect

    Schunk, Peter Randall; Dunphy, Darren Robert (University of New Mexico, Albuquerque, NM); Brinker, C. Jeffrey; Tjiptowidjojo, Kristianto (University of New Mexico, Albuquerque, NM)

    2010-09-01

    Heightened interest in micro-scale and nano-scale patterning by imprinting, embossing, and nano-particulate suspension coating stems from a recent surge in development of higher-throughput manufacturing methods for integrated devices. Energy-applications addressing alternative, renewable energy sources offer many examples of the need for improved manufacturing technology for micro and nano-structured films. In this presentation we address one approach to micro- and nano-pattering coating using film deposition and differential wetting of nanoparticles suspensions. Rather than print nanoparticle or colloidal inks in discontinuous patches, which typically employs ink jet printing technology, patterns can be formed with controlled dewetting of a continuously coated film. Here we report the dynamics of a volatile organic solvent laden with nanoparticles dispensed on the surfaces of water droplets, whose contact angles (surface energy) and perimeters are defined by lithographic patterning of initially (super)hydrophobic surfaces.. The lubrication flow equation together with averaged particle transport equation are employed to predict the film thickness and particle average concentration profiles during subsequent drying of the organic and water solvents. The predictions are validated by contact angle measurements, in situ grazing incidence small angle x-ray scattering experiments, and TEM images of the final nanoparticle assemblies.

  6. Linear sweep anodic stripping voltammetry of heavy metals from nitrogen doped tetrahedral amorphous carbon thin films

    Microsoft Academic Search

    N. W. Khun; E. Liu

    2009-01-01

    Nitrogen doped tetrahedral amorphous carbon (ta-C:N) thin films were deposited on p-Si (111) substrates (1×10?3 to 6×10?3?cm) by a filtered cathodic vacuum arc technique with different nitrogen flow rates (3 and 20sccm). The ta-C:N film coated samples were used as working electrodes to detect trace heavy metals such as zinc (Zn), lead (Pb), copper (Cu) and mercury (Hg) by using

  7. Multilayer graphitic coatings for thermal stabilization of metallic nanostructures.

    PubMed

    Wilson, Peter M; Zobel, Adam; Lipatov, Alexey; Schubert, Eva; Hofmann, Tino; Sinitskii, Alexander

    2015-02-11

    We demonstrate that graphitic coatings, which consist of multilayer disordered graphene sheets, can be used for the thermal protection of delicate metal nanostructures. We studied cobalt slanted nanopillars grown by glancing angle deposition that were shown to melt at temperatures much lower than the melting point of bulk cobalt. After graphitic coatings were conformally grown over the surfaces of Co nanopillars by chemical vapor deposition, the resulting carbon-coated Co nanostructures retained their morphology at elevated temperatures, which would damage the uncoated structures. Thermal stabilization is also demonstrated for carbon-coated Ti nanopillars. The results of this study may be extended to other metallic and possibly even nonmetallic nanostructures that need to preserve their morphology at elevated temperatures in a broad range of applications. PMID:25594774

  8. Magnetic metal nanoparticles coated polyacrylonitrile textiles as microwave absorber

    NASA Astrophysics Data System (ADS)

    Akman, O.; Kavas, H.; Baykal, A.; Toprak, M. S.; Çoruh, Ali; Akta?, B.

    2013-02-01

    Polyacrylonitrile (PAN) textiles with 2 mm thickness are coated with magnetic nanoparticles in coating baths with Ni, Co and their alloys via an electroless metal deposition method. The crystal structure, morphology and magnetic nature of composites are investigated by X-ray Powder diffraction, Scanning Electron Microscopy, and dc magnetization measurement techniques. The frequency dependent microwave absorption measurements have been carried out in the frequency range of 12.4-18 GHz (X and P bands). Diamagnetic and ferromagnetic properties are also investigated. Finally, the microwave absorption of composites is found strongly dependent on the coating time. One absorption peak is observed between 14.3 and 15.8 GHz with an efficient absorption bandwidth of 3.3-4.1 GHz (under -20 dB reflection loss limit). The Reflection loss (RL) can be achieved between -30 and -50 dB. It was found that the RL is decreasing and absorption bandwidth is decreasing with increasing coating time. While absorption peak moves to lower frequencies in Ni coated PAN textile, it goes higher frequencies in Co coated ones. The Ni-Co alloy coated composites have fluctuating curve of absorption frequency with respect to coating time. These results encourage further development of magnetic nanoparticle coated textile absorbers for broadband applications.

  9. Tribology of metal-containing diamond-like carbon coatings

    Microsoft Academic Search

    Stephen J. Harris; Anita M. Weiner; Wen-Jin Meng

    1997-01-01

    Ball-on-disk tests were run for several commercial and in-house metal-containing diamond-like carbon (Me:DLC) coatings on steel coupons. The balls, which were made from either WC?Co or 52100 steel, developed normal stresses between roughly 100 MPa and 1 GPa during the course of the experiments. The wear resistance of the Me:DLC coatings from the various sources (running against WC balls) differed

  10. Comparative EIS study of pretreatment performance in coated metals

    Microsoft Academic Search

    Nie Tang; Wim J. van Ooij; George Górecki

    1997-01-01

    Various coated metal samples with different pretreatments were investigated by electrochemical impedance spectroscopy (EIS). Variables were the substrate (cold-rolled steel and hot-dipped galvanized steel), phosphate system (iron and zinc phosphate), post rinse (chromate and silane\\/zirconium rinse) and paint systems. The corrosion performance was determined on the basis of coating degradation, water uptake and interface delamination of the tested samples. The

  11. Chitosan based edible films and coatings: a review.

    PubMed

    Elsabee, Maher Z; Abdou, Entsar S

    2013-05-01

    Chitosan is a biodegradable biocompatible polymer derived from natural renewable resources with numerous applications in various fields, and one of which is the area of edible films and coatings. Chitosan has antibacterial and antifungal properties which qualify it for food protection, however, its weak mechanical properties, gas and water vapor permeability limit its uses. This review discusses the application of chitosan and its blends with other natural polymers such as starch and other ingredients for example essential oils, and clay in the field of edible films for food protection. The mechanical behavior and the gas and water vapor permeability of the films are also discussed. References dealing with the antimicrobial behavior of these films and their impact on food protection are explored. PMID:23498203

  12. Indentation of Metallic and Cermet Thermal Spray Coatings

    NASA Astrophysics Data System (ADS)

    Choi, W. B.; Prchlik, L.; Sampath, S.; Gouldstone, A.

    2009-03-01

    Indentation methods are presented by which the elastic and inelastic stress-strain characteristics of metallic thermal spray (TS) coatings on substrates may be extracted. The methods are based on existing techniques for brittle solids, and adapted for the finite geometry associated with coatings. Basic assumptions and derivations are given, along with guidelines for experimental measurement. Using these, indentation inelastic stress-strain curves are generated for NiCrAlY and Ni-Al bondcoats, as well as WC-Co cermet coatings. Elastic moduli are extracted for CoNiCrAlY coatings. Results are briefly discussed in the context of the effect of feedstock material, process and post-process heat treatment on the intrinsic properties of splats as well as their in-coating cohesion. The methods presented are attractive, particularly for the TS industry, due to the minimal specimen preparation and lack of intricate equipment required for measurement.

  13. Development of polypropylene film capacitor using double metallizing technology

    Microsoft Academic Search

    H. Takeoka; T. Saito; K. Shiota; T. Sasaki; S. Okabe; T. Nishimori

    2003-01-01

    PP film capacitors are widely used in AC applications for their excellent electrical characteristics such as low dielectric loss and high insulating resistance. We have developed PP film suitable for double metallizing and a new process which avoids blocking by decreasing surface energy of metallized layer. That process leads to improve moist-resistance of zinc metallized film. In this way, we

  14. Accurate Location and Manipulation of Nanoscaled Objects Buried under Spin-Coated Films.

    PubMed

    Rawlings, Colin; Wolf, Heiko; Hedrick, James L; Coady, Daniel J; Duerig, Urs; Knoll, Armin W

    2015-06-23

    Detection and precise localization of nanoscale structures buried beneath spin-coated films are highly valuable additions to nanofabrication technology. In principle, the topography of the final film contains information about the location of the buried features. However, it is generally believed that the relation is masked by flow effects, which lead to an upstream shift of the dry film's topography and render precise localization impossible. Here we demonstrate, theoretically and experimentally, that the flow-shift paradigm does not apply at the submicrometer scale. Specifically, we show that the resist topography is accurately obtained from a convolution operation with a symmetric Gaussian kernel whose parameters solely depend on the resist characteristics. We exploit this finding for a 3 nm precise overlay fabrication of metal contacts to an InAs nanowire with a diameter of 27 nm using thermal scanning probe lithography. PMID:26046586

  15. Metallic and nonmetallic coatings for ICF targets

    SciTech Connect

    Hendricks, C.D.; Crane, J.K.; Hsieh, E.J.; Meyer, S.F.

    1981-04-17

    Some fusion targets designed to be driven by 0.35 to 1 ..mu..m laser light are glass spheres coated with layers of various materials such as hydrocarbons, fluorocarbons, beryllium, copper, gold, platinum, etc. The glass shell, which is filled with gas, liquid or solid deuterium-tritium fuel, must have remarkably good surface and wall thickness uniformity. Methods for depositing the various materials will be discussed. They include plasma polymerization, electro-deposition, sputtering and evaporation. Many of the difficulties encountered in the coating processes are the result of coating on free spheres with very small radii - 35 to 500 micrometers. Several means of overcoming the problems will be described and experimental results presented.

  16. Laser marking using organo-metallic films

    Microsoft Academic Search

    M.-S. Khlif

    1996-01-01

    In this work, the technical aspects of laser marking using organo-metallic films of different compositions are reported. Orasols of different types and palladium (II) acetate are used, for the first time, to produce permanent markings of various colors on different substrates. Ceramic and plastic substrates were used. The deposition process is a photothermal process and the markings were carried out

  17. High transparency of classically opaque metallic films

    Microsoft Academic Search

    R. Dragila; B. Luther-Davies; S. Vukovic

    1985-01-01

    The surface-induced transparency of a stratified dielectric medium is theoretically and experimentally demonstrated. Expressions which define the conditions under which total transparency of a normally reflecting metal layer can be observed are presented. The transparency occurs when the conditions are established for the incident electromagnetic wave to excite coupled surface modes on both sides of the film. The theoretical results

  18. Thermal optimization of metalized polypropylene film capacitors

    Microsoft Academic Search

    M. H. El-Husseini; P. Venet; G. Rojat; C. Joubert

    2000-01-01

    In this study, the authors use an analytical model to calculate the losses in metalized polypropylene film capacitors. The model is validated experimentally for capacitors having the same capacitance but different geometry. For each series of capacitors, a temperature distribution in the roll is assumed with the aim of optimizing its thermal performance. It appears that the heating of a

  19. Graded coatings for metallic implant alloys

    SciTech Connect

    Saiz, Eduardo; Tomsia, Antoni P.; Fujino, Shigeru; Gomez-Vega, Jose M.

    2002-08-01

    Graded glass and glass-hydroxyapatite coatings on Ti-based and Co-Cr alloys have been prepared using a simple enameling technique. The composition of the glasses has been tailored to match the thermal expansion of the alloys. By controlling the firing time, and temperature, it has been possible to control the reactivity between the glass and the alloy and to fabricate coatings (25 to 150 mu m thick) with excellent adhesion to the substrate, resistant to corrosion and able to precipitate hydroxyapatite during in vitro tests in simulated body fluid.

  20. Direct observation and mechanism of increased emission sites in Fe-coated microcrystalline diamond films

    SciTech Connect

    Panda, Kalpataru; Sundaravel, B.; Panigrahi, B. K. [Materials Physics Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Huang, Pin-Chang; Shih, Wen-Ching [Graduate Institute in Electro-Optical Engineering, Tatung University, Taipei 104, Taiwan (China); Chen, Huang-Chin; Lin, I-Nan [Department of Physics, Tamkang University, New-Taipei 251, Taiwan (China)

    2012-06-15

    The electron field emission (EFE) properties of microcrystalline diamond (MCD) films are significantly enhanced due to the Fe coating and post-annealing processes. The 900 Degree-Sign C post-annealed Fe coated diamond films exhibit the best EFE properties, with a turn on field (E{sub 0}) of 3.42 V/{mu}m and attain EFE current density (J{sub e}) of 170 {mu}A/cm{sup 2} at 7.5 V/{mu}m. Scanning tunnelling spectroscopy (STS) in current imaging tunnelling spectroscopy mode clearly shows the increased number density of emission sites in Fe-coated and post-annealed MCD films than the as-prepared ones. Emission is seen from the boundaries of the Fe (or Fe{sub 3}C) nanoparticles formed during the annealing process. In STS measurement, the normalized conductance (dI/dV/I/V) versus V curves indicate nearly metallic band gap, at the boundaries of Fe (or Fe{sub 3}C) nanoparticles. Microstructural analysis indicates that the mechanism for improved EFE properties is due to the formation of nanographite that surrounds the Fe (or Fe{sub 3}C) nanoparticles.

  1. Preparing oxidizer coated metal fuel particles

    NASA Technical Reports Server (NTRS)

    Shafer, J. I.; Simmons, G. M. (inventors)

    1974-01-01

    A solid propellant composition of improved efficiency is described which includes an oxidizer containing ammonium perchlorate, and a powered metal fuel, preferably aluminum or beryllium, in the form of a composite. The metal fuel is contained in the crystalline lattice framework of the oxidizer, as well as within the oxidizer particles, and is disposed in the interstices between the oxidizer particles of the composition. The propellant composition is produced by a process comprising the crystallization of ammonium perchlorate in water, in the presence of finely divided aluminum or beryllium. A suitable binder is incorporated in the propellant composition to bind the individual particles of metal with the particles of oxidizer containing occluded metal.

  2. Pentek metal coating removal system: Baseline report

    SciTech Connect

    NONE

    1997-07-31

    The Pentek coating removal technology was tested and is being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU`s evaluation of efficiency and cost, this report covers evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The Pentek coating removal system consisted of the ROTO-PEEN Scaler, CORNER-CUTTER{reg_sign}, and VAC-PAC{reg_sign}. They are designed to remove coatings from steel, concrete, brick, and wood. The Scaler uses 3M Roto Peen tungsten carbide cutters while the CORNER-CUTTER{reg_sign} uses solid needles for descaling activities. These hand tools are used with the VAC-PAC{reg_sign} vacuum system to capture dust and debris as removal of the coating takes place. The safety and health evaluation during the testing demonstration focused on two main areas of exposure: dust and noise. Dust exposure minimal, but noise exposure was significant. Further testing for each exposure is recommended because of the environment where the testing demonstration took place. It is feasible that the dust and noise levels will be higher in an enclosed operating environment of different construction. In addition, other areas of concern found were arm-hand vibration, whole-body, ergonomics, heat stress, tripping hazards, electrical hazards, machine guarding, and lockout/tagout.

  3. Optimum antireflection coating for Antireflection-coated Metal-Oxide-Semiconductor /AMOS/ solar cells

    NASA Technical Reports Server (NTRS)

    Yeh, Y. C. M.; Ernest, F. P.; Stirn, R. J.

    1977-01-01

    Consideration is given to the design of a single-layer optimum antireflection coating for AMOS (antireflection-coated metal-oxide-semiconductor) solar cells to match the entire sunlight spectrum. The energy conversion efficiency is maximized by maximizing the open-circuit voltage and the short-circuit current. The former is maximized by oxidation techniques and the latter is maximized by the light-coupling into the solar cell. With reference to the effective index of refraction as obtained by ellipsometry, examples of optimum antireflection coatings for 60-A Au-GaAs solar cells are presented.

  4. Thickness Measurement of Gold Film Coating on Glass Substrate by X-Ray Fluorescence Technique

    Microsoft Academic Search

    Nirun Witit-anuna; Pichet Limsuwan; Weerapong Chewpraditkul

    Thickness is considered as one of the important characteristics of thin film. Almost all of film properties are related to film thickness such as electrical resistance, reflectance and transmittance of light. The objective of this research work is to study the thickness measurement of thin film by using X-ray fluorescence technique. Gold film samples have been coated on glass substrates

  5. Reduced graphene oxide coated thin aluminum film as an optoacoustic transmitter for high pressure and high frequency ultrasound generation

    NASA Astrophysics Data System (ADS)

    Hwan Lee, Seok; Park, Mi-ae; Yoh, Jack J.; Song, Hyelynn; Yun Jang, Eui; Hyup Kim, Yong; Kang, Sungchan; Seop Yoon, Yong

    2012-12-01

    We demonstrate that reduced graphene oxide (rGO) coated thin aluminum film is an effective optoacoustic transmitter for generating high pressure and high frequency ultrasound previously unattainable by other techniques. The rGO layer of different thickness is deposited between a 100 nm-thick aluminum film and a glass substrate. Under a pulsed laser excitation, the transmitter generates enhanced optoacoustic pressure of 64 times the aluminum-alone transmitter. A promising optoacoustic wave generation is possible by optimizing thermoelasticity of metal film and thermal conductivity of rGO in the proposed transmitter for laser-induced ultrasound applications.

  6. Metal alkoxide derived oriented and epitaxial ferroelectric thin films

    SciTech Connect

    Nashimoto, Keiichi [Fuji Xerox Co., Ltd., Kanagawa (Japan)

    1994-12-31

    Ferroelectric thin films including LiNbO{sub 3}, LiTaO{sub 3}, KNbO{sub 3}, and PZT were prepared by a process utilizing non-hydrolyzed metal methoxy-ethoxide precursors, spin coating, and rapid thermal annealing. Epitaxial and dense LiNbO{sub 3} and LiTaO{sub 3} films without any misoriented planes on sapphire (110) and (001) substrates were obtained with the present process. The LiNbO{sub 3} started to crystallize at 400{degrees}C and the refractive indices of LiNbO{sub 3} annealed over 600{degrees}C were close to those of bulk single crystals. Rocking curve full widths at half maximum (FWHM) for (110) of epitaxial LiNbO{sub 3} and LiTaO{sub 3} films on sapphire (110) less than 0.4{degrees} were observed. Epitaxial or highly oriented KNbO{sub 3} and PZT thin films with rocking curve FWHMs for (100) of 2.5{degrees} and 1.5{degrees}, respectively, were successfully grown on MgO (100) substrates.

  7. Fatigue Properties of Borosilicate Glass Coated with Two-Layered Ceramic Thin Films

    NASA Astrophysics Data System (ADS)

    Hoshide, Toshihiko; Tanaka, Motoki; Tsujiai, Hideki

    2013-04-01

    The long-term durability of ceramics coated glass with high performance should be appropriately evaluated prior to their applications. Fatigue properties of such materials should be clarified to ensure the long-term durability. In this work, a borosilicate glass was coated with single- and two-layered ceramic thin films by a sputtering method. Fatigue tests of coated glass were conducted under bending mode, and fatigue properties of coated glass were investigated. It was revealed that the fatigue life of glass coated with two-layered film became longer compared with those of glass substrate and glass coated single-layered film. Hardness as surface characteristics of coated films, and bending strength as bulk property of coated glass were correlated with the average fatigue life, though no good correlation was found between them. Fatigue resistance strength was proposed as another strength parameter. It was found that the average fatigue life was adequately expressed by a power function of fatigue resistance strength.

  8. Superhydrophobic anti-ultraviolet films by doctor blade coating

    NASA Astrophysics Data System (ADS)

    Cai, Chang-Yun; Lin, Kun-Yi Andrew; Yang, Hongta

    2014-11-01

    This article reports a scalable technology for fabricating polymer films with excellent water-repelling and anti-ultraviolet properties. A roll-to-roll compatible doctor blade coating technology is utilized to prepare silica colloidal crystal-polymer composites. The silica microspheres can then be selectively removed to create flexible self-standing macroporous polymer films with crystalline arrays of pores. The void sizes are controlled by tuning the duration of a reactive ion etching process prior to the removal of the templating silica microspheres. After surface modification, superhydrophobic surface can be achieved. This study further demonstrates that the as-prepared transparent porous films with 200 nm of pores exhibit diffraction of ultraviolet lights originated from the Bragg's diffractive of light from the three-dimensional highly ordered air cavities.

  9. Metallic coatings of microelectromechanical structures at low temperatures: Stress, elasticity, and nonlinear dissipation

    NASA Astrophysics Data System (ADS)

    Collin, E.; Kofler, J.; Lakhloufi, S.; Pairis, S.; Bunkov, Yu. M.; Godfrin, H.

    2010-06-01

    We present mechanical measurements performed at low temperatures on cantilever-based microelectromechanical structures coated with a metallic layer. Two very different coatings are presented in order to illustrate the capabilities of the present approach, namely (soft) aluminum and (hard) niobium oxide. The temperature is used as a control parameter to access materials properties. We benefit from low temperature techniques to extract a phase-resolved measurement of the first mechanical resonance mode in cryogenic vacuum. By repeating the experiment on the same samples, after multiple metallic depositions, we can determine accurately the contribution of the coating layers to the mechanical properties in terms of surface stress, additional mass, additional elasticity, and damping. Analytic theoretical expressions are derived and used to fit the data. Taking advantage of the extremely broad dynamic range provided by the technique, we can measure the anelasticity of the thin metallic film. The key parameters describing the metals' dynamics are analyzed in an original way in order to provide new experimental grounds for future theoretical modelings of the underlying mechanisms.

  10. COATING ALTERNATIVES GUIDE (CAGE) FOR METAL PARTS AND PRODUCTS PAINTING

    EPA Science Inventory

    The paper discusses the initial development of a Coating Alternatives Guide (CAGE) for metal parts and products painting. t is an innovative technology transfer approach that provides a tool to improve technology diffusion and assistance. t will provide vital, user-accessible inf...

  11. Silica Sol-Gel Coatings on Metals Produced by EPD

    Microsoft Academic Search

    Y. Castro; B. Ferrari; R. Moreno; A. Durán

    2003-01-01

    The objective of this work has been to combine the sol-gel method and the electrophoretic deposition (EPD) process to prepare thick coatings onto metallic substrates. Two different routes were used for preparing the sol-gel silica suspensions. On one hand, silica particulate sols were obtained by basic catalysis of alkoxides and alkylalkoxides. On the other, silica suspensions were prepared by adding

  12. Coated metal sintering carriers for fuel cell electrodes

    DOEpatents

    Donelson, Richard (Glen Waverly, AU); Bryson, E. S. (Downers Grove, IL)

    1998-01-01

    A carrier for conveying components of a fuel cell to be sintered through a sintering furnace. The carrier comprises a metal sheet coated with a water-based carbon paint, the water-based carbon paint comprising water, powdered graphite, an organic binder, a wetting agent, a dispersing agent and a defoaming agent.

  13. Coated metal sintering carriers for fuel cell electrodes

    DOEpatents

    Donelson, R.; Bryson, E.S.

    1998-11-10

    A carrier is described for conveying components of a fuel cell to be sintered through a sintering furnace. The carrier comprises a metal sheet coated with a water-based carbon paint, the water-based carbon paint comprising water, powdered graphite, an organic binder, a wetting agent, a dispersing agent and a defoaming agent.

  14. Metallic Bipolar Plates with Composite Coatings

    E-print Network

    heat and pressure Volume ratios and fluoropolymer type (PVDF, PCTFE and/or ECTFE) were varied ­ Lowest maintaining electrical and mechanical properties 0 1 2 3 4 5 6 7 8 Synthesis of Metal Boride Powders

  15. Indirect Methods For Determination of The Protective Effects of Coating Films on The Surface of Crystals

    Microsoft Academic Search

    J. Bajdik; K. Pintye-Hódi; Cs. Novák; A. Kelemen; G. Regdon; I. Er?s

    2002-01-01

    The extents of the protective effects of coating films on the surface of crystals were determined. Three different samples\\u000a were made with different quantities of coating fluid (Sepifilm LP 010 in 10% aqueous solution). Since the atomizing rate was\\u000a constant, the coating time increased in parallel with the volume of coating fluid applied. The direct measurement of film\\u000a thickness and

  16. Metal Oxide Thin Films Deposited from Metal Organic Precursors in Supercritical CO2 Solutions

    E-print Network

    Gougousi, Theodosia

    Metal Oxide Thin Films Deposited from Metal Organic Precursors in Supercritical CO2 Solutions of metal oxide thin films, including Al2O3, ZrO2, MnOx, and RuOx where the metal-organic precursors-ray photoelectron spectroscopy and infrared transmission confirmed metal oxide formation. We show that hydrogen

  17. Electrode modification with spin-coated films of mesoporous molecular sieve silicas

    Microsoft Academic Search

    Chaojie Song; Gilles Villemure

    2001-01-01

    Spin coating of mixtures of cetyltrimethylammonium chloride (CTACl) and prehydrolyzed tetramethyl orthosilicate (TMOS) on tin-doped indium oxide (ITO) conductive substrates gave transparent uniform coatings. Electron microscopy, X-ray diffraction and N2-adsorption showed the coatings to be continuous thin films of mesoporous MCM-41. Upon calcination, the thickness of the films decreased from 1.2 to 1.0 ?m, and cracks appeared in the films.

  18. All-metal AFM probes fabricated from microstructurally tailored Cu-Hf thin films.

    PubMed

    Luber, E J; Olsen, B C; Ophus, C; Radmilovic, V; Mitlin, D

    2009-08-26

    A growing number of atomic force microscope (AFM) applications make use of metal-coated probes. Probe metallization can cause adverse side-effects and disadvantages such as stress-induced cantilever bending, thermal expansion mismatch, increased tip radius and limited device lifetime due to coating wear. In this study we demonstrate how to overcome these limitations using microstructural design to create a metallic glass thin film alloy, from which monostructural all-metal AFM cantilevers are fabricated. A detailed compositional study of co-sputtered Cu-Hf films is performed using x-ray diffraction (XRD), nanoindentation, four-point probe and in situ multi-beam optical stress sensing (MOSS). Metallic glass Cu(90)Hf(10) films are found to possess an optimal combination of electrical resistivity (96 microOmega cm), nanoindentation hardness (5.2 GPa), ductility and incremental stress. A continuum model is developed which uses measured MOSS data to predict cantilever warping caused by stress gradients generated during film growth. Subsequently, a microfabrication process is developed to create Cu(90)Hf(10) AFM probes. Uncurled, 1 microm thick cantilevers having lengths of 100-400 microm are fabricated, with tip radii ranging from 10 to 40 nm. As a proof of principle, these all-metal Cu-Hf AFM probes are mounted in a commercial AFM and used to successfully image a known test structure. PMID:19652276

  19. All-metal AFM probes fabricated from microstructurally tailored Cu-Hf thin films

    NASA Astrophysics Data System (ADS)

    Luber, E. J.; Olsen, B. C.; Ophus, C.; Radmilovic, V.; Mitlin, D.

    2009-08-01

    A growing number of atomic force microscope (AFM) applications make use of metal-coated probes. Probe metallization can cause adverse side-effects and disadvantages such as stress-induced cantilever bending, thermal expansion mismatch, increased tip radius and limited device lifetime due to coating wear. In this study we demonstrate how to overcome these limitations using microstructural design to create a metallic glass thin film alloy, from which monostructural all-metal AFM cantilevers are fabricated. A detailed compositional study of co-sputtered Cu-Hf films is performed using x-ray diffraction (XRD), nanoindentation, four-point probe and in situ multi-beam optical stress sensing (MOSS). Metallic glass Cu90Hf10 films are found to possess an optimal combination of electrical resistivity (96 µ? cm), nanoindentation hardness (5.2 GPa), ductility and incremental stress. A continuum model is developed which uses measured MOSS data to predict cantilever warping caused by stress gradients generated during film growth. Subsequently, a microfabrication process is developed to create Cu90Hf10 AFM probes. Uncurled, 1 µm thick cantilevers having lengths of 100-400 µm are fabricated, with tip radii ranging from 10 to 40 nm. As a proof of principle, these all-metal Cu-Hf AFM probes are mounted in a commercial AFM and used to successfully image a known test structure.

  20. Method For Improving The Oxidation Resistance Of Metal Substrates Coated With Thermal Barrier Coatings

    DOEpatents

    Thompson, Anthony Mark (Niskayuna, NY); Gray, Dennis Michael (Delanson, NY); Jackson, Melvin Robert (Niskayuna, NY)

    2003-05-13

    A method for providing a protective coating on a metal-based substrate is disclosed. The method involves the application of an aluminum-rich mixture to the substrate to form a discontinuous layer of aluminum-rich particles, followed by the application of a second coating over the discontinuous layer of aluminum-rich particles. Aluminum diffuses from the aluminum-rich layer into the substrate, and into any bond coat layer which is subsequently applied. Related articles are also described. A method for providing a protective coating on a metal-based substrate is disclosed. The method involves the application of an aluminum-rich mixture to the substrate to form a discontinuous layer of aluminum-rich particles, followed by the application of a second coating over the discontinuous layer of aluminum-rich particles. Aluminum diffuses from the aluminum-rich layer into the substrate, and into any bond coat layer which is subsequently applied. Related articles are also described.

  1. A molecular dynamics study of metal coating on SWNT Abstract Metal coating process on single-walled carbon nanotube (SWNTs) was investigated

    E-print Network

    Maruyama, Shigeo

    SWNT A molecular dynamics study of metal coating on SWNT 1) , 1) , 1) ( 1) ) Abstract Metal coating process on single-walled carbon nanotube (SWNTs) was investigated using molecular dynamics simulations size and temperature highlight the roles of molecular dynamics on the resulting metal morphologies. [1

  2. Metallic coating techniques for fiber Bragg grating sensors

    NASA Astrophysics Data System (ADS)

    Grandal, T.; Piñeiro, E.; Asensio, A.; Rodriguez, F.

    2013-11-01

    Fiber Bragg Grating sensors (FBG) have a great resistance to embedding processes. This property is very useful for monitoring parameters at inaccessible places. Embedded fiber optic sensors into composites have been studied for a long time, but embedding a fiber sensor into metallic structure is beginning to study. Recently, this has raised interest due to embedded FBG in the metallic structure provide capabilities for controlling parameters of the structural health status and also information about their own process of deterioration. The embedding process of the FBG sensors involves the fusion of structural metallic material. During this process, very high temperatures are achieved that could damage the Bragg grating or the silica fiber. To protect the sensor during the embedding process, a fiber coating is made with a metallic material with a high melting point. In this paper we study three different techniques for coating a FBG sensor: physical vapour deposition (PVD), electroless deposition and electroplating. This paper describes the experimental procedure for coating metallic fiber optic sensors and the optical characterization.

  3. Dynamics of polymer film formation during spin coating

    SciTech Connect

    Mouhamad, Y.; Clarke, N.; Jones, R. A. L.; Geoghegan, M., E-mail: geoghegan@sheffield.ac.uk [Department of Physics and Astronomy, The University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom); Mokarian-Tabari, P. [Materials Research Group, Department of Chemistry and the Tyndall National Institute, University College Cork, Cork (Ireland)

    2014-09-28

    Standard models explaining the spin coating of polymer solutions generally fail to describe the early stages of film formation, when hydrodynamic forces control the solution behavior. Using in situ light scattering alongside theoretical and semi-empirical models, it is shown that inertial forces (which initially cause a vertical gradient in the radial solvent velocity within the film) play a significant role in the rate of thinning of the solution. The development of thickness as a function of time of a solute-free liquid (toluene) and a blend of polystyrene and poly(methyl methacrylate) cast from toluene were fitted to different models as a function of toluene partial pressure. In the case of the formation of the polymer blend film, a concentration-dependent (Huggins) viscosity formula was used to account for changes in viscosity during spin coating. A semi-empirical model is introduced, which permits calculation of the solvent evaporation rate and the temporal evolution of the solute volume fraction and solution viscosity.

  4. Dynamics of polymer film formation during spin coating

    NASA Astrophysics Data System (ADS)

    Mouhamad, Y.; Mokarian-Tabari, P.; Clarke, N.; Jones, R. A. L.; Geoghegan, M.

    2014-09-01

    Standard models explaining the spin coating of polymer solutions generally fail to describe the early stages of film formation, when hydrodynamic forces control the solution behavior. Using in situ light scattering alongside theoretical and semi-empirical models, it is shown that inertial forces (which initially cause a vertical gradient in the radial solvent velocity within the film) play a significant role in the rate of thinning of the solution. The development of thickness as a function of time of a solute-free liquid (toluene) and a blend of polystyrene and poly(methyl methacrylate) cast from toluene were fitted to different models as a function of toluene partial pressure. In the case of the formation of the polymer blend film, a concentration-dependent (Huggins) viscosity formula was used to account for changes in viscosity during spin coating. A semi-empirical model is introduced, which permits calculation of the solvent evaporation rate and the temporal evolution of the solute volume fraction and solution viscosity.

  5. Investigation of Cu coatings deposited by kinetic metallization

    SciTech Connect

    Han, Y.K. [ARC Centre of Excellence for Design in Light Metals (Australia); Department of Materials Engineering, Monash University, VIC 3800 (Australia); Birbilis, N., E-mail: nick.birbilis@eng.monash.edu.au [ARC Centre of Excellence for Design in Light Metals (Australia); Department of Materials Engineering, Monash University, VIC 3800 (Australia); Spencer, K.; Zhang, M.-X. [ARC Centre of Excellence for Design in Light Metals (Australia); School of Engineering, Division of Materials, University of Queensland, St Lucia, QLD 4072 (Australia); Muddle, B.C. [ARC Centre of Excellence for Design in Light Metals (Australia); Department of Materials Engineering, Monash University, VIC 3800 (Australia)

    2010-11-15

    Interfacial characterisation of Kinetic Metallization (KM) sprayed Cu coatings applied on metal substrates was performed using optical and electron microscopy, as well as microindentation hardness testing and microchemical analysis. The interfacial characterisation of KM coatings remains scarce to date. Cross sectional observations of KM coatings on light metal substrates revealed an undulating, patelliform profile with thin-lipped cusps at the interface. Pure Al and Mg substrates exhibited a mechanically impinged zone <{approx}5 {mu}m on the substrate material, approximately the size of deformed Cu powder particles. Examination of the Cu side of the interface indicated there was no long range interaction in the coating. On the substrate side of the interface, the KM process induced phase transformations (i.e. recrystallisation and an alloyed zone) in thin layers contiguous to the interface on pure Al and Mg substrates. Zones of elemental interdiffusion were identified at the interface upon Al and Mg substrates using scanning TEM. The width of intermixing zones was in the vicinity of < 1 {mu}m. This metallurgical interaction at the interface occurred on the length scales involving the initial single layer of Cu particles bonded on the substrate.

  6. The effect of film thickness on the failure strain of polymer-supported metal films

    E-print Network

    Suo, Zhigang

    The effect of film thickness on the failure strain of polymer-supported metal films Nanshu Lu-supported copper films with a strong (1 1 1) fiber texture and with thicknesses varying from 50 nm to 1 lm. Films with thicknesses below 200 nm fail by intergranular fracture at elongations of only a few percent. Thicker films

  7. Process for the preparation of metal-containing nanostructured films

    NASA Technical Reports Server (NTRS)

    Lu, Yunfeng (Inventor); Wang, Donghai (Inventor)

    2006-01-01

    Metal-containing nanostructured films are prepared by electrodepositing a metal-containing composition within the pores of a mesoporous silica template to form a metal-containing silica nanocomposite. The nanocomposite is annealed to strengthen the deposited metal-containing composition. The silica is then removed from the nanocomposite, e.g., by dissolving the silica in an etching solution to provide a self-supporting metal-containing nanostructured film. The nanostructured films have a nanowire or nanomesh architecture depending on the pore structure of the mesoporous silica template used to prepare the films.

  8. Metal matrix coated fiber composites and the methods of manufacturing such composites

    DOEpatents

    Weeks, Jr., Joseph K. (Salt Lake City, UT); Gensse, Chantal (Salt Lake City, UT)

    1993-01-01

    A fiber coating which allows ceramic or metal fibers to be wetted by molten metals is disclosed. The coating inhibits degradation of the physical properties caused by chemical reaction between the fiber and the coating itself or between the fiber and the metal matrix. The fiber coating preferably includes at least a wetting layer, and in some applications, a wetting layer and a barrier layer between the fiber and the wetting layer. The wetting layer promotes fiber wetting by the metal matrix. The barrier layer inhibits fiber degradation. The fiber coating permits the fibers to be infiltrated with the metal matrix resulting in composites having unique properties not obtainable in pure materials.

  9. Fabrication and characterization of thin, spin-coated, sol-gel, and colloidal silica films

    Microsoft Academic Search

    David L. Williams; Sven G. Roden; Terence A. King; Kevin R. Welford

    1994-01-01

    This study was conducted on both inorganic silica and organically modified silica (ormosil) films. Sol-gel derived silica films were prepared by spin-coating either a sol or a colloidal silica (COLSI) suspension mixed with a polysiloxane solution onto glass substrates. The films were microscopically investigated to reveal their structure. The optical quality of the films was measured using a scatterometer which

  10. Physicochemical properties of film-coated melt-extruded pellets.

    PubMed

    Young, Chistopher R; Crowley, Michael; Dietzsch, Caroline; McGinity, James W

    2007-02-01

    The purpose of this study was to investigate the physicochemical properties of poly(ethylene oxide) (PEO) and guaifenesin containing beads prepared by a melt-extrusion process and film-coated with a methacrylic acid copolymer. Solubility parameter calculations, thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), modulated differential scanning calorimetry (MDSC), X-ray powder diffraction (XRPD) and high performance liquid chromatography (HPLC) were used to determine drug/polymer miscibility and/or the thermal processibility of the systems. Powder blends of guaifenesin, PEO and functional excipients were processed using a melt-extrusion and spheronization technique and then film-coated in a fluidized bed apparatus. Solubility parameter calculations were used to predict miscibility between PEO and guaifenesin, and miscibility was confirmed by SEM and observation of a single melting point for extruded drug/polymer blends during MDSC investigations. The drug was stable following melt-extrusion as determined by TGA and HPLC; however, drug release rate from pellets decreased upon storage in sealed HDPE containers with silica desiccants at 40 degrees C/75% RH. The weight loss on drying, porosity and tortuosity determinations were not influenced by storage. Recrystallization of guaifenesin and PEO was confirmed by SEM and XRPD. Additionally, the pellets exhibited a change in adhesion behaviour during dissolution testing. The addition of ethylcellulose to the extruded powder blend decreased and stabilized the drug release rate from the thermally processed pellets. The current study also demonstrated film-coating to be an efficient process for providing melt-extruded beads with pH-dependent drug release properties that were stable upon storage at accelerated conditions. PMID:17438942

  11. Pulsed-laser deposited transition-metal carbides for field-emission cathode coatings.

    PubMed

    Back, Tyson; Fairchild, Steven B; Averett, Kent; Maruyama, Benji; Pierce, Neal; Cahay, Marc; Murray, P Terrence

    2013-09-25

    Thin films of transition-metal carbides ZrC, HfC, and TiC were deposited by pulsed-laser deposition under vacuum. The surface chemistry of the films was characterized with ultraviolet photoelectron spectroscopy, X-ray photoelectron spectroscopy, and Auger electron spectroscopy in situ. X-ray diffraction was used to characterize the film structure. TiC was shown to be nearly stoichiometric and polycrystalline. The TiC was applied to a vertically aligned carbon nanotube sample and characterized by field emission. Field-emission results showed enhanced current and current density at a film thickness, 5 nm, not previously reported in the literature. Emission from TiC films was also shown to be less affected by adsorbates during field emission. Pulsed-laser deposition of TiC offers a distinct advantage over other techniques in that high-quality films can be obtained under ultrahigh vacuum conditions without the use of a reactive background gas or excessively high annealing temperatures. The application of TiC by pulsed-laser deposition as a cathode coating shows potential for integration into a fabrication process. PMID:23988076

  12. Plasmonic enhancement of thin-film solar cells using gold-black coatings

    SciTech Connect

    Fredricksen, Christopher J.; Panjwani, D. R.; Arnold, J. P.; Figueiredo, P. N.; Rezaie, F. K.; Colwell, J. E.; Baillie, K.; Peppernick, Samuel J.; Joly, Alan G.; Beck, Kenneth M.; Hess, Wayne P.; Peale, Robert E.

    2011-08-11

    Coatings of conducting gold-black nano-structures on commercial thin-film amorphous-silicon solar cells enhance the short-circuit current by 20% over a broad spectrum from 400 to 800 nm wavelength. The efficiency, i.e. the ratio of the maximum electrical output power to the incident solar power, is found to increase 7% for initial un-optimized coatings. Metal blacks are produced cheaply and quickly in a low-vacuum process requiring no lithographic patterning. The inherently broad particle-size distribution is responsible for the broad spectrum enhancement in comparison to what has been reported for mono-disperse lithographically deposited or self-assembled metal nano-particles. Photoemission electron microscopy reveals the spatial-spectral distribution of hot-spots for plasmon resonances, where scattering of normally-incident solar flux into the plane increases the effective optical path in the thin film to enhance light harvesting. Efficiency enhancement is correlated with percent coverage and particle size distribution, which are determined from histogram and wavelet analysis of scanning electron microscopy images. Electrodynamic simulations reveal how the gold-black particles scatter the radiation and locally enhance the field strength.

  13. Plasmonic enhancement of thin-film solar cells using gold-black coatings

    NASA Astrophysics Data System (ADS)

    Fredricksen, C. J.; Panjwani, D. R.; Arnold, J. P.; Figueiredo, P. N.; Rezaie, F. K.; Colwell, J.; Baillie, K.; Peppernick, S. J.; Joly, A. G.; Beck, K. M.; Hess, W. P.; Peale, R. E.

    2011-09-01

    Coatings of conducting gold-black nano-structures on commercial thin-film amorphous-silicon solar cells enhance the short-circuit current by 20% over a broad spectrum from 400 to 800 nm wavelength. The efficiency, i.e. the ratio of the maximum electrical output power to the incident solar power, is found to increase 7% for initial un-optimized coatings. Metal blacks are produced cheaply and quickly in a low-vacuum process requiring no lithographic patterning. The inherently broad particle-size distribution is responsible for the broad spectrum enhancement in comparison to what has been reported for mono-disperse lithographically deposited or self-assembled metal nano-particles. Photoemission electron microscopy reveals the spatial-spectral distribution of hot-spots for plasmon resonances, where scattering of normally-incident solar flux into the plane increases the effective optical path in the thin film to enhance light harvesting. Efficiency enhancement is correlated with percent coverage and particle size distribution, which are determined from histogram and wavelet analysis of scanning electron microscopy images. Electrodynamic simulations reveal how the gold-black particles scatter the radiation and locally enhance the field strength.

  14. Soluble aromatic polyimides for film and coating applications

    NASA Technical Reports Server (NTRS)

    St.clair, Anne K.; St.clair, Terry L.

    1987-01-01

    Linear all-aromatic polyimides have been synthesized and characterized which show much potential as films and coatings for electronic applications. Structure-property relations with regard to methods for obtaining solubility of fully imidized polymers will be discussed. Methods used to obtain solubility include variation of polymer molecular structure, variation of isomerism of the diamine monomer, modification of cure time/temperature and atmosphere. Other properties of soluble polyimides will be presented which include glass transition temperatures, thermooxidative stabilities, UV-visible spectra, and refractive indices.

  15. Inclined-substrate deposition of biaxially textured magnesium oxide thin films for YBCO coated conductors.

    SciTech Connect

    Ma, B.; Li, M.; Jee, Y. A.; Koritala, R. E.; Fisher, B. L.; Balachandran, U.; Energy Technology

    2002-02-01

    Highly textured MgO films were grown by the inclined-substrate deposition (ISD) technique at a high deposition rate. A columnar grain with a roofing-tile-shaped surface was observed in these MgO films. X-ray pole figure, and {phi}- and {omega}-scan were used to characterize in-plane and out-of-plane textures. MgO films deposited when the incline angle {alpha} was 55 and 30 degrees exhibited the best in-plane and out-of-plane texture, respectively. High-quality YBCO films were epitaxially grown on ISD-MgO-buffered Hastelloy C substrates by pulsed laser deposition. {Tc}=88 K, with sharp transition, and j{sub c} values of {approx}2x10{sup 5} A/cm{sup 2} at 77 K in zero field were observed on films 5 mm wide and 1 cm long. This work has demonstrated that biaxially textured ISD MgO buffer layers deposited on metal substrates are excellent candidates for fabrication of high-quality YBCO coated conductors.

  16. Electrochemical Synthesis of Nanostructured Noble Metal Films for Biosensing

    NASA Astrophysics Data System (ADS)

    Bhattarai, Jay K.

    Nanostructures of noble metals (gold and silver) are of interest because of their important intrinsic properties. Noble metals by themselves are physically robust, chemically inert, highly conductive, and possess the capability to form strong bonds with thiols or dithiol molecules present in organic compounds, creating self-assembled monolayers with tunable functional groups at exposed interfaces. However, when the nanostructures are formed, they in addition possess high surface area and unique optical properties which can be tuned by adjusting the shape and the size of the nanostructures. All of these properties make nanostructures of noble metals suitable candidates to be used as a transducer for optical and electrochemical biosensing. Individual nanostructures might be easier to prepare but difficult to handle to use as a transducer. Therefore, we prepared and analyzed nanostructured films/coating of noble metals and used them as a transducer for optical and electrochemical biosensing. We have electrochemically prepared nanoporous gold (NPG) on gold wire varying different dependable parameters (deposition potential, time, and compositional ratio) to obtain an optimal structure in term of stability, morphology, and better surface area. NPG prepared using a deposition potential of --1.0 V for 10 min from 30:70% 50 mM potassium dicyanoaurate(I) and 50 mM potassium dicyanoargentate(I) was used as an optimal surface for protein immobilization, and to perform square wave voltammetry (SWV) based enzyme-linked lectinsorbent assays. On flat gold surfaces, adjacent protein molecules sterically block their active sites due to high-density packing, which can be minimized using NPG as a substrate. NPG can also show significant peak current in SWV experiments, a sensitive electrochemical technique that minimizes non-Faradaic current, which is difficult to obtain using a flat gold surface. These all make NPG a suitable substrate, electrode, and transducer to be used in electrochemical biosensing. We have also discovered a facile electrochemical method to synthesize novel plasmonic noble metal nanostructured films. Plasmonic noble metal nanostructures have promising applications in photovoltaic solar cells, cloaking, and molecular sensing. Here, we used plasmonic noble metal nanostructures as a transducer for biosensing using localized surface plasmon resonance (LSPR) spectroscopy, a label-free biosensing technique. The prepared nanostructured films are not only sensitive for detecting biomolecules, but are stable chemically and physically, and can be easily regenerated. We have compared the sensitivity of three different types of nanostructured films, namely; nanostructured gold film (NGF), nanostructured silver film (NSF), and NPG film, and discussed the advantages and disadvantages of the prepared structures. Finally, we report carbohydrate--lectin, lectin--protein, and layer-by-layer interactions of molecules using LSPR spectroscopy. We have also performed real-time interactions and concentration dependent studies to find the equilibrium dissociation constant of the interactions. The results from these experiments could contribute to the development of cheap and sensitive biosensors that can be used for diagnostic purposes.

  17. The role of size and coating in Au nanoparticles incorporated into bi-component polymeric thin-film transistors.

    PubMed

    Mosciatti, Thomas; Orgiu, Emanuele; Raimondo, Corinna; Samorì, Paolo

    2014-05-21

    We describe the effect of blending poly(3-hexylthiophene) (P3HT) with Au nanoparticles (AuNPs) on the performance of organic thin-film transistors. To this end we have used AuNPs of two different sizes coated with chemisorbed SAMs of oligophenyl-thiols possessing increasing lengths. The electrical characteristics of the hybrid materials revealed changes in the field-effect mobility depending primarily on the AuNP size, as a result of the variable energy level of the coated metallic nanocluster and by the degree of modification of the P3HT crystalline structure. PMID:24604238

  18. Development of polycrystalline silicon films on flexible metallic substrates by aluminium induced crystallization

    NASA Astrophysics Data System (ADS)

    Prathap, P.; Slaoui, A.; Ducros, C.; Baclet, N.; Reydet, P. L.

    2009-10-01

    Thin film silicon solar cells on low cost foreign substrates could be attractive for highly efficient and low cost production of photovoltaic electricity. An attempt has been made to synthesise high-quality continuous polycrystalline silicon ( pc-Si) layers on flexible metallic substrates using aluminium induced crystallization (AIC) for the first time. Amorphous silicon films deposited by ECR-PECVD were crystallized on diffusion barrier coated metallic substrates at lower temperatures (<577°C). The crystallization was studied using Raman as well as UV reflectance spectroscopy. The as-grown AIC pc-Si films were found to be continuous and densely packed without amorphous phase. The migration of impurities from the substrate to the pc-Si films and the conformability of the barrier layer with the substrate and pc-Si films were studied systematically in terms of chemical and stress level analysis, which are the important aspects to be considered when metallic foils are used as substrates. It was observed that the barrier layer also serves as a buffer layer to minimise the stress level enormously in the AIC grown pc-Si layer, though the supporting material has a thermal expansion coefficient of higher order at higher annealing temperatures. The present investigation proves the possibility to grow better-quality polycrystalline silicon films on flexible metallic foils and further demonstrates the steps that need to be considered to improve the quality of AIC pc-Si films as well as the strength of the barrier layer.

  19. Metal oxide coatings for piezoelectric exhaust gas sensors

    SciTech Connect

    Anderson, M.T.; Cernosek, R.W.

    1996-06-01

    We have deposited ZrO{sub 2}, TiO{sub 2}, and SnO{sub 2} films on ST-cut quartz surface acoustic wave (SAW) devices via sol-gel techniques. The films range from 100 to 300 nm thick and have porosities after calcination at 300{degrees}C that range from 82-88 % for ZrO{sub 2}, 77-81% for TiO{sub 2}, and 57-66% for SnO{sub 2}. In all cases, we have varied the synthesis and processing parameters over a wide range to optimize film properties: metal ion concentration (0.05-1.0 M), the H{sub 2}O:metal ratio (0.3-5.3), the acid concentration in the sol (0.02-0.7 M), the modifier ligand:metal ratio (r = 0.0-1.0), the processing conditions (100-900{degrees}C). The modifier ligand, triethanolamine (TEA), is added to each solution to allow multilayer films to be made crack free. The multilayer films are studied by optical microscopy, ellipsometry, X-ray diffraction, and N{sub 2} sorption. Preliminary high temperature frequency response measurements to target gases, such as, H{sub 2}, NO, NO{sub 2}, and propylene indicate limited sensitivity for the configurations tested.

  20. Antimicrobial beeswax coated polylactide films with silver control release capacity.

    PubMed

    Martínez-Abad, Antonio; Lagarón, Jose Maria; Ocio, María Jose

    2014-03-17

    Although the application of silver based antimicrobial systems is a widespread technology, its implementation in areas such as food packaging is still challenging. The present paper describes the fabrication of poly(lactic acid) (PLA) coated with beeswax with controlled release properties for sustained antimicrobial performance. Release of silver ions from the polymers was monitored voltammetrically under various conditions (surface contact, immersion in various liquid media and at different pH values) throughout at least 7days. A higher release was noted with decreasing pH while surface release was much slower than the release when immersed in liquid medium. While uncoated films demonstrated a high burst release which in some instances implied surpassing some current migration restrictions (<0.05mg/kg food), the addition of a beeswax layer allowed a sustained release of the antimicrobial compound. Increasing the thickness of the beeswax layer resulted in an increase in the water barrier properties of the films while reducing the relatively constant values of sustained release. Antimicrobial performance was correlated with the release of silver ions, indicating threshold concentrations for biocide action of <6?g/L and 9-14?g/L for surface contact and in liquid media, respectively. Either by surface contact or by immersion in growth medium or vegetable soup, the coated films displayed a strong bactericidal effect against Salmonella enterica. The application of this functional barrier thus offers the possibility of tuning the release profiles of the films to suit a specific application and puts forth the possible suitability of these materials for food packaging or other migration sensitive applications. PMID:24448276

  1. Electrochromic properties of spin-coated thin films from peroxo-polymolybdovanadate solutions

    SciTech Connect

    Li, Y.; Kudo, Tetsuichi [Univ. of Tokyo (Japan). Inst. of Industrial Science

    1995-04-01

    A now mixed metal peroxo-polyacid based on Mo and V is formed by the direct reaction of a mixture of metallic Mo and V with hydrogen peroxide solution. A homogeneous amorphous thin film about 0.4 {mu}m is fabricated on an indium tin oxide (ITO) glass substrate by a spin-coating technique using this peroxo-polymolybdovanadate solution. After heat-treatment from 80 to 120 C in air for 1 h, it shows reversible electrochromism in an organic LiClO{sub 4} electrolyte solution, and changes color from greenish yellow to grayish violet and violet, depending on the intercalation level of Li. Cyclic-voltammograms of the mixed Mo/V oxide film and those of the end members (MoO{sub 3} and V{sub 2}O{sub 5}) are quite different from one another, both in shape and peak-current potential, indicating that each film has distinctly different intercalation electrochemistry. The potential (E) vs. composition (x, Li content per mol Mo{sub 0.5}V{sub 0.5}O{sub 2.75}) diagram of the present film recorded in the intercalation process agrees with that of the deintercalation process in the range 0 < x < 1.5. The E-x relationship is approximated by two straight lines with different slopes, with a kink at x = 0.5. This suggests that in this film there are two kinds of sites with different site energies. The changes in electrochromic properties with heat-treatment are also discussed in relation to the microstructure of the film.

  2. Characteristics of Nanohybrid Coating Films Synthesized from Colloidal Silica and Organoalkoxysilanes by Sol-Gel Process

    NASA Astrophysics Data System (ADS)

    Na, Moonkyong; Park, Hoyyul; Kang, Dongpil; Ahn, Myeongsang; Lee, Heewoong

    2008-01-01

    Organic-inorganic hybrid sols were synthesized using colloidal silica and organoalkoxysilane using the sol-gel process. Hybrid sols were functionalized using methyltrimethoxysilane (MTMS) and ?-glycidoxypropyltrimethoxysilane (GTMS). Coating films were formed on a glass substrate using a spin coating procedure. The hybrid sols were evaluated for stability and thermal degradation. Viscosity increased markedly when the hybrid sols were reacted for 10 d. It was found that the hybrid sols reacted over 10 d were difficult to be used as coating agents. The thermal degradation of a colloidal silica (CS)/MTMS sample occurred at 650 °C owing to the decomposition of a methyl group. Two CS/MTMS/GTMS samples degraded at 400 °C owing to the decomposition of an epoxy group. Coating films were characterized in terms of hydrophobicity, surface morphology, and electrical resistance. CS/MTMS coating films showed a high contact angle, indicating hydrophobic character. The contact angle of the CS/MTMS/GTMS coating film decreased owing to epoxy group when a large amount of GTMS was added. The roughness of all coating films was less than 20 nm. The surface resistance of the coating films reacted for 7 d was measured. The surface resistance of the coating films was more than 1013 ?.

  3. Rate controlled synthesis of composition modulated, metal-oxide thin films

    SciTech Connect

    Jankowski, A.F.

    1994-07-01

    The development of advanced deposition technologies is continuously evolving for the synthesis of oxide coatings used in optical applications. Recent progress is made in the use of magnetron sputtering to reactively deposit metal-oxide thin films. Sputter deposition parameters are chosen to vary the composition along the film growth direction. The key process parameter to control is the sputtering rate of the target. The shape of the composition profile directly corresponds to the preselected variation of deposition rate. By simply varying the sputtering rate using a working gas that consists of an inert-oxygen mixture, structures are synthesized with composition profiles which can be either abrupt or graded in the growth direction. Result is a compositionally modulated structure of the metal-oxide system. This procedure for composition modulated synthesis is demonstrated for metals which are highly reactive with oxygen as well as for those metals which are not. The development of this deposition methodology will facilitate the design of metal oxide films for optical applications, as in gradient-index filters for example. Results are presented for the reactive sputter deposition of metal oxide coatings in the Y-O, Mo-O, and Cu-O systems.

  4. Linking Precursor Alterations to Nanoscale Structure and Optical Transparency in Polymer Assisted Fast-Rate Dip-Coating of Vanadium Oxide Thin Films

    PubMed Central

    Glynn, Colm; Creedon, Donal; Geaney, Hugh; Armstrong, Eileen; Collins, Timothy; Morris, Michael A.; Dwyer, Colm O’

    2015-01-01

    Solution processed metal oxide thin films are important for modern optoelectronic devices ranging from thin film transistors to photovoltaics and for functional optical coatings. Solution processed techniques such as dip-coating, allow thin films to be rapidly deposited over a large range of surfaces including curved, flexible or plastic substrates without extensive processing of comparative vapour or physical deposition methods. To increase the effectiveness and versatility of dip-coated thin films, alterations to commonly used precursors can be made that facilitate controlled thin film deposition. The effects of polymer assisted deposition and changes in solvent-alkoxide dilution on the morphology, structure, optoelectronic properties and crystallinity of vanadium pentoxide thin films was studied using a dip-coating method using a substrate withdrawal speed within the fast-rate draining regime. The formation of sub-100?nm thin films could be achieved rapidly from dilute alkoxide based precursor solutions with high optical transmission in the visible, linked to the phase and film structure. The effects of the polymer addition was shown to change the crystallized vanadium pentoxide thin films from a granular surface structure to a polycrystalline structure composed of a high density of smaller in-plane grains, resulting in a uniform surface morphology with lower thickness and roughness. PMID:26123117

  5. Linking Precursor Alterations to Nanoscale Structure and Optical Transparency in Polymer Assisted Fast-Rate Dip-Coating of Vanadium Oxide Thin Films.

    PubMed

    Glynn, Colm; Creedon, Donal; Geaney, Hugh; Armstrong, Eileen; Collins, Timothy; Morris, Michael A; Dwyer, Colm O'

    2015-01-01

    Solution processed metal oxide thin films are important for modern optoelectronic devices ranging from thin film transistors to photovoltaics and for functional optical coatings. Solution processed techniques such as dip-coating, allow thin films to be rapidly deposited over a large range of surfaces including curved, flexible or plastic substrates without extensive processing of comparative vapour or physical deposition methods. To increase the effectiveness and versatility of dip-coated thin films, alterations to commonly used precursors can be made that facilitate controlled thin film deposition. The effects of polymer assisted deposition and changes in solvent-alkoxide dilution on the morphology, structure, optoelectronic properties and crystallinity of vanadium pentoxide thin films was studied using a dip-coating method using a substrate withdrawal speed within the fast-rate draining regime. The formation of sub-100?nm thin films could be achieved rapidly from dilute alkoxide based precursor solutions with high optical transmission in the visible, linked to the phase and film structure. The effects of the polymer addition was shown to change the crystallized vanadium pentoxide thin films from a granular surface structure to a polycrystalline structure composed of a high density of smaller in-plane grains, resulting in a uniform surface morphology with lower thickness and roughness. PMID:26123117

  6. Ultrathin, ordered oxide films on metal surfaces

    NASA Astrophysics Data System (ADS)

    Chen, M. S.; Goodman, D. W.

    2008-07-01

    Metal oxides and oxide thin films are extensively used as active catalysts and catalytic supports, as well as in many other important technical applications. Unlike TiO2, which is a semiconductor and can be investigated using a variety of surface science techniques, most metal oxides are insulators, which seriously restricts their use as model surfaces with modern surface science techniques. This difficulty can be circumvented by synthesizing ultrathin oxide films a few nanometers in thickness with well-defined structures, that mimic the corresponding bulk oxides yet are thin enough to be sufficiently conducting. In this review, preparations, structures, electronic and chemical properties of four representative oxides, alumina, magnesium oxide, silica, and titania, are addressed. Of these MgO is found to grow in a layer-by-layer fashion, allowing preparation of crystalline thin film structures with varying thicknesses. Crystalline TiO2 and Ti2O3 can also be synthesized, whereas SiO2 and Al2O3, although amenable to synthesis as well-defined monolayer structures, have only been grown to date as amorphous multilayers.

  7. Repairing Chipped Silicide Coatings on Refractory Metal Substrates

    NASA Technical Reports Server (NTRS)

    Youngquist, Robert

    2006-01-01

    The space shuttle orbiter s reaction control system (RCS) is a series of small thrusters that use hypergolic fuels to orient the orbiter in space. The RCS thrusters are constructed from a special niobium-based alloy -- the C-103. This alloy retains excellent mechanical properties from cryogenic temperature all the way up to 2,500 F (1,370 C). C-103 is susceptible to rapid oxidation at elevated temperatures. The authors have developed two methods to repair damaged R512a coatings on C-103. For the first repair technique, metal foundries, semiconductor manufacturers, and many other industries have developed and routinely use coatings that can easily be painted on metal to protect it from corrosion, including oxidation, to temperatures in excess of 2,500 F (1,370 C). This first repair technique is considered somewhat temporary. The second repair technique is based on using the native coating material of the RCS nozzles. the chipped area is ground out and a "green" R512a coating is applied to the repair area. Both repair techniques can be applied for moderate protection until the permanent laser-repair technique is available to the repair area.

  8. Applying terahertz technology for nondestructive detection of crack initiation in a film-coated layer on a swelling tablet.

    PubMed

    Momose, Wataru; Yoshino, Hiroyuki; Katakawa, Yoshifumi; Yamashita, Kazunari; Imai, Keiji; Sako, Kazuhiro; Kato, Eiji; Irisawa, Akiyoshi; Yonemochi, Etsuo; Terada, Katsuhide

    2012-01-01

    Here, we describe a nondestructive approach using terahertz wave to detect crack initiation in a film-coated layer on a drug tablet. During scale-up and scale-down of the film coating process, differences in film density and gaps between the film-coated layer and the uncoated tablet were generated due to differences in film coating process parameters, such as the tablet-filling rate in the coating machine, spray pressure, and gas-liquid ratio etc. Tablets using the PEO/PEG formulation were employed as uncoated tablets. We found that heat and humidity caused tablets to swell, thereby breaking the film-coated layer. Using our novel approach with terahertz wave nondestructively detect film surface density (FSD) and interface density differences (IDDs) between the film-coated layer and an uncoated tablet. We also found that a reduced FSD and IDD between the film-coated layer and uncoated tablet increased the risk of crack initiation in the film-coated layer, thereby enabling us to nondestructively predict initiation of cracks in the film-coated layer. Using this method, crack initiation can be nondestructively assessed in swelling tablets after the film coating process without conducting accelerated stability tests, and film coating process parameters during scale-up and scale-down studies can be appropriately established. PMID:25755992

  9. Peculiarities of nanostructured silicon carbide films and coatings obtained by novel technique

    Microsoft Academic Search

    K. N. Filonov; V. N. Kurlov; N. V. Klassen; E. A. Kudrenko; E. A. Shteinman

    2009-01-01

    A new method has been developed for obtaining various versions of nanostructured SiC films and coatings, whose structure can\\u000a be altered in a controlled way for different applications. The films and coatings obtained can be useful in metallurgy, nuclear\\u000a power industry, microelectronics, and high-temperature furnaces.

  10. Interaction of beam and coated metals at high power continuous irradiation

    NASA Astrophysics Data System (ADS)

    Kim, Yong Hyeon; Baek, Won-Kye; Yoh, Jack J.

    2011-07-01

    The beam-matter interaction with various coating effects has received continued attention in the high power laser community. Previous works suggest that coatings promote target damage when compared to beaming on uncoated surface. Three types of paint coatings (acrylic urethane, silicone alkyd and stealth blend) and a water coat on metals (Al, Ti and STS) are irradiated with a CO 2 laser. Both strain and temperature measurements are provided for assessing the instantaneous response characteristics of each coating on different metals. A selective combination of surface coats with metals has been proven to be effective in either preventing or enhancing damage, both thermal and mechanical, associated with focused beaming on a target.

  11. STRUCTURE, PROPERTIES AND APPLICATIONS OF EDIBLE FILMS AND COATINGS FROM DAIRY PROTEINS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Based on their barrier properties, edible films from casein improve the quality of food and non-food products when applied as coatings. For example, casein coatings hinder lipid oxidation when applied to fresh meats. When applied to the surface of paperboard, casein coatings improve moisture barri...

  12. Method for nondestructive testing of the film coating behavior of surface acoustic wave (SAW) sensors

    NASA Astrophysics Data System (ADS)

    Taslakov, M. A.; Avramov, I. D.

    2010-04-01

    This paper presents a practical non-destructive method for studying the film coating behavior of SAW devices by using a water soluble dielectric film (manitol) deposited on the SAW device surface by resistive evaporation. After measuring the electrical parameters of the film coated SAW device, the film can easily be removed from its surface by water rinsing without causing any damage to it. The SAW device can then be used over and over again in a large number of film depositions. The method was tested on a 1 GHz surface transverse wave (STW) resonator coated with manitol of varying thickness. After each coating and evaluation, the STW device was successfully recovered without significant performance degradation. Data is presented on the electrical changes of the STW device as a result of depositing manitol coatings of various thicknesses.

  13. Effect of Ceramic Particle Velocity on Cold Spray Deposition of MetalCeramic Coatings

    Microsoft Academic Search

    A. Sova; V. F. Kosarev; A. Papyrin; I. Smurov

    2011-01-01

    In this paper, metal-ceramic coatings are cold sprayed taking into account the spray parameters of both metal and ceramic\\u000a particles. The effect of the ceramic particle velocity on the process of metal-ceramic coating formation and the coating properties\\u000a is analyzed. Copper and aluminum powders are used as metal components. Two fractions of aluminum oxide and silicon carbide\\u000a are sprayed in

  14. Anomalous hopping exponents of ultrathin metal films

    NASA Astrophysics Data System (ADS)

    Phillips, J. C.

    2001-07-01

    Under the above title Markovic et al. [Phys. Rev. B 62, 2195 (2000)] summarized their and others' low-temperature data that show that a consistent underlying conduction mechanism is needed to explain thermally activated resistivities, with an exponent x=0.75(5), on films of Ag, Bi, Pb, and Pd, with thicknesses of 5-15 Å. While this x cannot be explained by any kind of conventional continuum hopping model, with or without Coulomb interactions, here it is shown that the exponent x=34 is the direct result of a filamentary vibron quantum percolation model appropriate to a granular network film. The concepts used in this model were recently used to derive finite-size scaling exponents and/or phase diagrams in many other contexts, including network glasses, the impurity band metal-insulator transition, high-temperature superconductors, and evolutionary biology.

  15. Metallic oxide switches using thick film technology

    NASA Technical Reports Server (NTRS)

    Patel, D. N.; Williams, L., Jr.

    1974-01-01

    Metallic oxide thick film switches were processed on alumina substrates using thick film technology. Vanadium pentoxide in powder form was mixed with other oxides e.g., barium, strontium copper and glass frit, ground to a fine powder. Pastes and screen printable inks were made using commercial conductive vehicles and appropriate thinners. Some switching devices were processed by conventional screen printing and firing of the inks and commercial cermet conductor terminals on 96% alumina substrates while others were made by applying small beads or dots of the pastes between platinum wires. Static, and dynamic volt-ampere, and pulse tests indicate that the switching and self-oscillatory characteristics of these devices could make them useful in memory element, oscillator, and automatic control applications.

  16. Directed Assembly of PEGylated-Peptide Coatings for Infection-Resistant Titanium Metal

    E-print Network

    integration and performance of any implant, whether metal, plastic, or ceramic. A robust peptide-based coatingDirected Assembly of PEGylated-Peptide Coatings for Infection-Resistant Titanium Metal Xiaojuan, a PEGylated analogue of the peptide was shown to rapidly coat Ti to afford a nonfouling surface

  17. Hydrophobic coating of solid materials by plasma-polymerized thin film using tetrafluoroethylene

    NASA Technical Reports Server (NTRS)

    Hozumi, K.; Kitamura, K.; Kitade, T.

    1980-01-01

    Glass slides were coated with plasma-polymerized tetrafluoroethylene films of different thickness using the glow discharge technique in a tube-shaped chamber, and the plasma conditions, film growth rates, light permeability of the polymer films, and particle bond strength in the polymer films were studied. Ashed sections of mouse organs and ashed bacillus spores were also coated to give them hydrophobic treatment without damaging their shapes or appearance. The hydrophobic coating of the specimens was successful, and the fine ash patterns were strongly fixed onto the glass slides, making permanent preparations.

  18. Detection of Volatile Organic Compounds by Weight-Detectable Sensors coated with Metal-Organic Frameworks

    NASA Astrophysics Data System (ADS)

    Yamagiwa, Hiroki; Sato, Seiko; Fukawa, Tadashi; Ikehara, Tsuyoshi; Maeda, Ryutaro; Mihara, Takashi; Kimura, Mutsumi

    2014-09-01

    Detection of volatile organic compounds (VOCs) using weight-detectable quartz microbalance and silicon-based microcantilever sensors coated with crystalline metal-organic framework (MOF) thin films is described in this paper. The thin films of two MOFs were grown from COOH-terminated self-assembled monolayers onto the gold electrodes of sensor platforms. The MOF layers worked as the effective concentrators of VOC gases, and the adsorption/desorption processes of the VOCs could be monitored by the frequency changes of weight-detectable sensors. Moreover, the MOF layers provided VOC sensing selectivity to the weight-detectable sensors through the size-selective adsorption of the VOCs within the regulated nanospace of the MOFs.

  19. Detection of Volatile Organic Compounds by Weight-Detectable Sensors coated with Metal-Organic Frameworks

    PubMed Central

    Yamagiwa, Hiroki; Sato, Seiko; Fukawa, Tadashi; Ikehara, Tsuyoshi; Maeda, Ryutaro; Mihara, Takashi; Kimura, Mutsumi

    2014-01-01

    Detection of volatile organic compounds (VOCs) using weight-detectable quartz microbalance and silicon-based microcantilever sensors coated with crystalline metal-organic framework (MOF) thin films is described in this paper. The thin films of two MOFs were grown from COOH-terminated self-assembled monolayers onto the gold electrodes of sensor platforms. The MOF layers worked as the effective concentrators of VOC gases, and the adsorption/desorption processes of the VOCs could be monitored by the frequency changes of weight-detectable sensors. Moreover, the MOF layers provided VOC sensing selectivity to the weight-detectable sensors through the size-selective adsorption of the VOCs within the regulated nanospace of the MOFs. PMID:25175808

  20. Tribology of a novel UHMWPE\\/PFPE dual-film coated onto Si surface

    Microsoft Academic Search

    N. Satyanarayana; Sujeet K. Sinha; Boon Hong Ong

    2006-01-01

    A novel wear resistant polymer composite layer is coated onto the Si surface. The first layer consists of ultra-high molecular weight polyethylene (UHMWPE) film and the second top layer is made of perfluoropolyether (PFPE). These two layers are coated onto Si using a simple dip-coating technique. This particular combination of dual-film has reduced the coefficient of friction by at least

  1. Corrosion behavior of rare earth metal (REM) conversion coatings on aluminum alloy LY12

    Microsoft Academic Search

    Yu Xingwen; Cao Chunan; Yao Zhiming; Zhou Derui; Yin Zhongda

    2000-01-01

    The processes of the double layer rare earth metal (REM) conversion coating on aluminum alloy LY12 (2024) were introduced. The results of polarization tests showed that the corrosion resistance of the double layer REM conversion coating was superior to that of chromate conversion coating. The corrosion behavior of REM conversion coatings on LY12 alloy was studied with optical microscopy and

  2. Preparation of metallic coatings on polymer matrix composites by cold spray

    Microsoft Academic Search

    X. L. Zhou; A. F. Chen; J. C. Liu; X. K. Wu; J. S. Zhang

    2011-01-01

    In the present work, an Al metallic coating and an Al\\/Cu bimetallic coating were prepared on the surface of a carbon fiber-reinforced polymer matrix composite (PMC) using a cold spray system with nitrogen as process and powder carrier gas. The microstructure, microhardness, and bond strength of the resultant coatings are analyzed. The bonding mechanism of the coatings, especially the deposition

  3. Interaction of beam and coated metals at high power continuous irradiation

    Microsoft Academic Search

    Yong Hyeon Kim; Won-Kye Baek; Jack J. Yoh

    2011-01-01

    The beam-matter interaction with various coating effects has received continued attention in the high power laser community. Previous works suggest that coatings promote target damage when compared to beaming on uncoated surface. Three types of paint coatings (acrylic urethane, silicone alkyd and stealth blend) and a water coat on metals (Al, Ti and STS) are irradiated with a CO2 laser.

  4. Electronic Properties of Ultrathin d-Band Metal Films with Simple Metal or Vacuum Interfaces

    Microsoft Academic Search

    Bernard R. Cooper

    1973-01-01

    The Green's-function method has been used to study the changes in electronic structure of fcc d-band metals on going to ultrathin films. Varying the boundary where the electronic wave functions vanish allows an accurate treatment both for a d-band metal film embedded in a simple metal and for a d-band metal film in vacuum. Calculations for a copper monolayer predict

  5. Fabrication and characterization of thin, spin-coated, sol-gel, and colloidal silica films

    NASA Astrophysics Data System (ADS)

    Williams, David L.; Roden, Sven G.; King, Terence A.; Welford, Kevin R.

    1994-10-01

    This study was conducted on both inorganic silica and organically modified silica (ormosil) films. Sol-gel derived silica films were prepared by spin-coating either a sol or a colloidal silica (COLSI) suspension mixed with a polysiloxane solution onto glass substrates. The films were microscopically investigated to reveal their structure. The optical quality of the films was measured using a scatterometer which measured the intensity of light scattered from the films as a function of angle of scatter. Scatterometry allowed the quantitative study of the factors that affect film quality, particularly film composition and number of layers spun. The effect of heating the film in-between the application of successive coatings was also investigated. Various tools were used to inspect the films, these include interferometric profilometry, probe profilometry, phase-contrast and confocal optical microscopy, and electron microscopy. Laser dyes and also various molecules possessing significant nonlinear optical properties have been successfully incorporated into the films.

  6. Radiation damage in nanostructured metallic films

    NASA Astrophysics Data System (ADS)

    Yu, Kaiyuan

    High energy neutron and charged particle radiation cause microstructural and mechanical degradation in structural metals and alloys, such as phase segregation, void swelling, embrittlement and creep. Radiation induced damages typically limit nuclear materials to a lifetime of about 40 years. Next generation nuclear reactors require materials that can sustain over 60 - 80 years. Therefore it is of great significance to explore new materials with better radiation resistance, to design metals with favorable microstructures and to investigate their response to radiation. The goals of this thesis are to study the radiation responses of several nanostructured metallic thin film systems, including Ag/Ni multilayers, nanotwinned Ag and nanocrystalline Fe. Such systems obtain high volume fraction of boundaries, which are considered sinks to radiation induced defects. From the viewpoint of nanomechanics, it is of interest to investigate the plastic deformation mechanisms of nanostructured films, which typically show strong size dependence. By controlling the feature size (layer thickness, twin spacing and grain size), it is applicable to picture a deformation mechanism map which also provides prerequisite information for subsequent radiation hardening study. And from the viewpoint of radiation effects, it is of interest to explore the fundamentals of radiation response, to examine the microstructural and mechanical variations of irradiated nanometals and to enrich the design database. More importantly, with the assistance of in situ techniques, it is appealing to examine the defect generation, evolution, annihilation, absorption and interaction with internal interfaces (layer interfaces, twin boundaries and grain boundaries). Moreover, well-designed nanostructures can also verify the speculation that radiation induced defect density and hardening show clear size dependence. The focus of this thesis lies in the radiation response of Ag/Ni multilayers and nanotwinned Ag subjected to charged particles. The radiation effects in irradiated nanograined Fe are also investigated for comparison. Radiation responses in these nanostructured metallic films suggest that immiscible incoherent Ag/Ni multilayers are more resistant to radiation in comparison to their monolithic counterparts. Their mechanical properties and radiation response show strong layer thickness dependence in terms of radiation hardening and defect density. Coherent twin boundaries can interact with stacking fault tetrahedral and remove them effectively. Twin boundaries can actively absorb radiation induced defects and defect clusters resulting in boundary migration. Size dependence is also found in nanograins where fewer defects exhibit in films with smaller grains.

  7. Properties of Induction Plasma Sprayed Iron Based Nanostructured Alloy Coatings for Metal Based Thermal Barrier Coatings

    Microsoft Academic Search

    Dong-Il Shin; François Gitzhofer; Christian Moreau

    2007-01-01

    Metal-based thermal barrier coatings (MBTBCs) have been produced using high frequency induction plasma spraying (IPS) of iron-based\\u000a nanostructured alloy powders. The study of MBTBCs has been initiated to challenge issues associated with current TBC materials\\u000a such as difficult prediction of their “in-service” lifetime. Reliability of TBCs is an important aspect besides the economical\\u000a consideration. Therefore, the study of MBTBCs, which

  8. Generation of metal, metal oxide and metal-metal oxide powders by spray pyrolysis for microelectronic thick film applications

    Microsoft Academic Search

    Diptarka Majumdar

    1997-01-01

    Materials in powdered form have wide ranging applications. In thick film microelectronics, powders are dispersed in organic liquids to form pastes which are screen printed on ceramic substrates and fired to fabricate active and passive electronic devices. The functional phase is a metal powder in conductive pastes, a metal or conductive metal oxide powder in resistive pastes and a ceramic

  9. Enhanced thermoelectric performance of bar-coated SWCNT/P3HT thin films.

    PubMed

    Lee, Woohwa; Hong, Cheon Taek; Kwon, O Hwan; Yoo, Youngjae; Kang, Young Hun; Lee, Jun Young; Cho, Song Yun; Jang, Kwang-Suk

    2015-04-01

    The influence of processing conditions, such as ink concentration and coating method, on the thermoelectric properties of SWCNT/P3HT nanocomposite films was investigated systematically. Using simple wire-bar-coating, SWCNT/P3HT nanocomposite films with high thermoelectric performance could be obtained without additional P3HT doping. The wire-bar-coated SWCNT/P3HT nanocomposite films exhibited power factors of up to 105 ?W m(-1) K(-2) at room temperature. The SWCNT bundles with diameters in the range of 6-23 nm formed an interconnected network in the wire-bar-coated nanocomposite films. Network formation in these nanocomposite films was expected to be strongly related to the development of electrical pathways due to inter-SWCNT bundle connections. This study suggests that the thermoelectric performance of SWCNT/P3HT nanocomposite films could be optimized by controlling their processing conditions and morphology. PMID:25762308

  10. Tribological coatings for complex mechanical elements produced by supersonic cluster beam deposition of metal dichalcogenide nanoparticles

    NASA Astrophysics Data System (ADS)

    Piazzoni, C.; Buttery, M.; Hampson, M. R.; Roberts, E. W.; Ducati, C.; Lenardi, C.; Cavaliere, F.; Piseri, P.; Milani, P.

    2015-07-01

    Fullerene-like MoS2 and WS2 nanoparticles can be used as building blocks for the fabrication of fluid and solid lubricants. Metal dichalcogenide films have a very low friction coefficient in vacuum, therefore they have mostly been used as solid lubricants in space and vacuum applications. Unfortunately, their use is significantly hampered by the fact that in the presence of humidity, oxygen and moisture, the low-friction properties of these materials rapidly degrade due to oxidation. The use of closed-cage MoS2 and WS2 nanoparticles may eliminate this problem, although the fabrication of lubricant thin films starting from dichalcogenide nanoparticles is, to date, a difficult task. Here we demonstrate the use of supersonic cluster beam deposition for the coating of complex mechanical elements (angular contact ball bearings) with nanostructured MoS2 and WS2 thin films. We report structural and tribological characterization of the coatings in view of the optimization of tribological performances for aerospace applications.

  11. Preparation of cobalt doped nickel ferrite thin films on optical fibers by dip-coating technique

    Microsoft Academic Search

    Miroslav Sedlar; Ladislav Pust

    1995-01-01

    Cobalt doped NiFe2O4 thin films were synthesized using dip-coating wet-chemical process using a solution of iron (III) nitrate dissolved in ethylene glycol and 2-methoxyethanol. Films coated on flat (alumina plates, fused silica, slide glass) substrates and optical fibers were dense and without defects. The onset of the film crystallization was between 450 and 500 °C and crystallinity increased with increasing

  12. Film formation and paper coating with poly ([beta]-hydroxyalkanoate), a biodegradable latex

    SciTech Connect

    Lauzier, C.A.; Monasterios, C.J.; Saracovan, I.; Marchessault, R.H. (McGill Univ., Montreal, Quebec (Canada)); Ramsay, B.A. (Ecole Polytechnique de Montreal, Quebec (Canada))

    1993-05-01

    An aqueous latex of a poly ([beta]-hydroxyalkanoate) (PHA) coated on paper imparted water imperviousness without changing mechanical properties. Hot-pressed films biodegraded faster than solvent cast films. The PHA coating on paper degraded totally in activated sludge within 12 days, leaving the cellulose matrix relatively untouched. Blends of PHA latexes with sodium carboxymethl cellulose, polystyrene latex, carboxylated styrenel butadiene latex, natural rubber latex, carboxylated styrenel butadiene latex; natural rubber latex, and starch powders form satisfactory films at room temperature.

  13. Development, mechanical evaluation and surface characteristics of chitosan/polyvinyl alcohol based polymer composite coatings on titanium metal.

    PubMed

    Mishra, Sandeep K; Kannan, S

    2014-12-01

    Mechanical properties of orthopedic implants play important role in the regeneration and cell growth of the diseased body part. The present investigation was aimed at the development of a biocompatible, biodegradable and mechanically stable coating of chitosan (CS)-polyvinyl alcohol (PVA) polymer composite on Titanium (Ti) metal by employing a simple methodology at ambient conditions. The PVA to CS concentrations were maintained in fixed ratios of 1:4 weight/weight (w/w) for the development of all the coatings on Ti metal. Four different concentrations of the polymers ranging in the order of 5%, 10%, 15% and 20% weight/volume (w/v) solution of CS were selected in an aim to test their efficacy on mechanical stability. The results obtained from the analysis confirmed considerable improvement in mechanical properties of the composite polymer film comprising CS and PVA on Ti metal with the four different concentrations showing variable elastic modulus and hardness. The difference in mechanical properties of both dehydrated and hydrated coatings demonstrates the effective and efficient shielding of high mechanical properties of Ti metal in physiological conditions. The scratch tests performed on the coated specimens also indicated a good adhesion of the polymer on the Ti metal surface. PMID:25265031

  14. Cyclic nanoindentation studies on CrN thin films prepared by RF sputtering on Zr-based metallic glass

    SciTech Connect

    Jellad, A.; Benameur, T. [Laboratoire de Genie Mecanique LGM-MA05, ENIM, Av. Ibn El Jazzar, 5019 Monastir (Tunisia); Labdi, S. [Laboratoire d'etudes des Milieux Nanometriques, UEVE, Bd F. Mitterand, 91025 Evry Cedex (France)

    2011-01-17

    Cyclic nanoindentation tests were carried out to study the influence of the chromium nitride thin films on the mechanical properties of Zr-based metallic glass. Chromium nitride thin coatings have been deposited on Zr{sub 50}Cu{sub 40}Al{sub 10} metallic glass substrate by RF sputtering. The deposition process was done at room temperature under nitrogen reactive gas using a metallic chromium target. The CrN films have a thickness of 300 nm. Several cyclic nanoindentation measurements were conducted on CrN films and Zr{sub 50}Cu{sub 40}Al{sub 10} metallic glass substrate samples at various loading rate values. We have found that the coated metallic glass sample shows high mechanical properties such as hardness and reduced elastic modulus. Cyclic nanoindentation results show a hardening behaviour for these CrN coatings. Moreover, the CrN coated on Zr-based metallic glass was found to have a high value of resistance to crack propagation, as being analysed through the SEM pictures of the residual Vickers indentation impressions.

  15. Simulations of enhanced absorption in composite embedded, insulated metal nanopatterns for ultrathin film photovoltaics

    NASA Astrophysics Data System (ADS)

    Liu, Xinyu; Ye, Fan; Burns, Michael J.; Naughton, Michael J.

    2012-02-01

    In recent work [1], a concept of employing embedded metallic nanopatterns (EMN) in ultrathin film solar cells was discussed. Elsewhere in this conference, Fan et al. advance this with a scheme for embedded insulated metallic nanopatterns (EIMN) that is designed to avoid deleterious carrier recombination as would result from bare metal inclusions in a PV film. However, a practical route to fabricating EIMNs of desired shapes for eventual scale production is nontrivial. Here, we introduce two notions toward that goal, nano-stamping and spin-coating, of compact arrays of metallic core/insulating shell nanoparticles (MNP). We show by simulations that optical absorption of an EIMN composed of arrays of core-shell MNPs having SiO2 coatings is essentially the same as that of an EMN composed of solid metals without insulation, with absorption concentrated in the surrounding PV medium. These concepts may provide practical routes for scalability of EIMN-based ultrathin film plasmonic solar cells.[4pt] [1] F. Ye, M. J. Burns, M. J. Naughton, Proc. SPIE 8111, 811103 (2011), and this conference.

  16. Nanocomposite metal amorphous-carbon thin films deposited by hybrid PVD and PECVD technique.

    PubMed

    Teixeira, V; Soares, P; Martins, A J; Carneiro, J; Cerqueira, F

    2009-07-01

    Carbon based films can combine the properties of solid lubricating graphite structure and hard diamond crystal structure, i.e., high hardness, chemical inertness, high thermal conductivity and optical transparency without the crystalline structure of diamond. Issues of fundamental importance associated with nanocarbon coatings are reducing stress, improving adhesion and compatibility with substrates. In this work new nanocomposite coatings with improved toughness based in nanocrystalline phases of metals and ceramics embedded in amorphous carbon matrix are being developed within the frame of a research project: nc-MeNxCy/a-C(Me) with Me = Mo, Si, Al, Ti, etc. Carbide forming metal/carbon (Me/C) composite films with Me = Mo, W or Ti possess appropriate properties to overcome the limitation of pure DLC films. These novel coating architectures will be adopted with the objective to decrease residual stress, improve adherence and fracture toughness, obtain low friction coefficient and high wear-resistance. Nanocomposite DLC's films were deposited by hybrid technique using a PVD-Physically Vapor Deposition (magnetron sputtering) and Plasma Enhanced Chemical Vapor Deposition (PECVD), by the use of CH4 gas. The parameters varied were: deposition time, substrate temperature (180 degrees C) and dopant (Si + Mo) of the amorphous carbon matrix. All the depositions were made on silicon wafers and steel substrates precoated with a silicon inter-layer. The characterisation of the film's physico-mechanical properties will be presented in order to understand the influence of the deposition parameters and metal content used within the a-C matrix in the thin film properties. Film microstructure and film hybridization state was characterized by Raman Spectroscopy. In order to characterize morphology SEM and AFM will be used. Film composition was measured by Energy-Dispersive X-ray analysis (EDS) and by X-ray photoelectron spectroscopy (XPS). The contact angle for the produced DLC's on silicon substrates were also measured. Thin film adherence was studied by micro-scratch test. Residual stresses in the produced coatings will be analysed by bending technique. PMID:19916409

  17. Transition Metal Oxides: Extra Thermodynamic Stability as Thin Films

    Microsoft Academic Search

    Charles T. Campbell

    2006-01-01

    Introduction.—Transition metals are used as industrial catalysts for a wide range of oxidation reactions of great importance in fuel processing, chemical production, and pollution cleanup. A key fundamental question is whether the surface under catalytic reaction conditions is metallic or is, instead, the metal's oxide. We show here that since these oxides often wet their metals, an? 1n mthick film

  18. Spectral behavior of thin film coated cascaded tapered long period gratings in multiple configurations.

    PubMed

    Pilla, P; Foglia Manzillo, P; Giordano, M; Korwin-Pawlowski, M L; Bock, W J; Cusano, A

    2008-06-23

    In this work the spectral response of cascaded tapered long period gratings coated by nano-sized polymeric films has been investigated as function of the surrounding medium refractive index (SRI). The investigation was aimed to identify the best configuration in terms of coated/not coated areas in order to fully benefit of the SRI sensitivity enhancement due to the modal transition mechanism of nano-coated long period gratings while preserving the fringes visibility. PMID:18575545

  19. Evaluation of Adhesive Behaviors of Chromium Nitride Coating Films Produced by Arc Ion Plating Method

    Microsoft Academic Search

    Ri-Ichi Murakami; Yun-Hae Kim; Kazushi Kimura; Daisuke Yonekura; Do-Hoon Shin

    2006-01-01

    Scratch tests and pin-on-disk wear tests were performed to clarify the cracking and delaminating behavior of CrN coatings. The CrN films were coated onto an aluminum alloy substrate, JIS A2024, by an arc ion plating method. Eight types of single-layered coating and multilayered coatings were prepared by changing the bias voltage during the deposition. LCI and LCII values were not

  20. Measuring the thickness of protective coatings on historic metal objects using nanosecond and femtosecond laser induced breakdown spectroscopy depth profiling

    NASA Astrophysics Data System (ADS)

    Pouli, P.; Melessanaki, K.; Giakoumaki, A.; Argyropoulos, V.; Anglos, D.

    2005-08-01

    Depth profile analysis by means of laser induced breakdown spectroscopy (LIBS) was investigated with respect to its potential to measure the thickness of different types of thin organic films used as protective coatings on historical and archaeological metal objects. For the materials examined, acrylic varnish and microcrystalline wax, the output from a nanosecond ArF excimer laser at 193 nm was found appropriate for performing a reliable profiling of the coating films leading to accurate determination of the coating thickness on the basis of the number of laser pulses required to penetrate the coating and on the ablation etch rate of the corresponding coating material under the same irradiation conditions. Nanosecond pulses at 248 nm proved inadequate to profile the coatings because of their weak absorption at the laser wavelength. In contrast, femtosecond irradiation at 248 nm yielded well-resolved profiles as a result of efficient ablation achieved through the increased non-linear absorption induced by the high power density of the ultrashort pulses.

  1. Method of applying a bond coating and a thermal barrier coating on a metal substrate, and related articles

    DOEpatents

    Hasz, Wayne Charles (Pownal, VT); Borom, Marcus Preston (Tucson, AZ)

    2002-01-01

    A method for applying at least one bond coating on a surface of a metal-based substrate is described. A foil of the bond coating material is first attached to the substrate surface and then fused thereto, e.g., by brazing. The foil is often initially prepared by thermally spraying the bond coating material onto a removable support sheet, and then detaching the support sheet. Optionally, the foil may also include a thermal barrier coating applied over the bond coating. The substrate can be a turbine engine component.

  2. Reaction mechanism of electroless metal deposition using ZnO thin film (I): Process of catalyst formation

    SciTech Connect

    Yoshiki, Hajime; Hashimoto, Kazuhito; Fujishima, Akira [Univ. of Tokyo (Japan). Dept. of Applied Chemistry

    1995-02-01

    The reaction mechanism of electroless metal deposition proceeding selectively on a ZnO thin film coated on a glass substrate was investigated by X-ray diffraction, X-ray photoelectron spectroscopy, and inductively coupled plasma measurements. The ZnO thin film was activated for electroless metal deposition just by immersion in 1.1 mM PdCl{sub 2} solution adjusted to pH 2.5. In this process, PD(II) was selectively adsorbed on the ZnO thin film while simultaneously the ZnO underwent dissolution. The dissolution of ZnO thin film easily occurred on the (002) face with polarity. The strongly adsorbed Pd(II) was reduced to Pd(0) by a reducing agent in the electroless plating bath and this served as a catalyst center. As a result, metal layers were obtained selectively on the ZnO thin film in the electroless plating bath.

  3. Photophysical and photocatalytic properties of Bi 2MNbO 7 (M = Al, In, Ga, Fe) thin films prepared by dip-coating

    Microsoft Academic Search

    J. L. Ropero-Vega; K. L. Rosas-Barrera; J. A. Pedraza-Avella; D. A. Laverde-Cataño; J. E. Pedraza-Rosas; M. E. Niño-Gómez

    2010-01-01

    In this work we report the preparation and characterization of Bi2MNbO7 (M=Al, Ga, In, Fe) transparent thin films on glass slides. The films were obtained by dip-coating using bismuth(III) acetate, niobium(V) ethoxide and the corresponding metal(III) acetylacetonate precursors. Crystal structure and elemental analysis were performed by X-ray diffraction (XRD) and energy dispersive X-ray fluorescence (EDXRF). The band-gap energy (Eg) of

  4. A molecular dynamics study of metal coating on SWNT Teppei Matsuo, Junichiro Shiomi and Shigeo Maruyama

    E-print Network

    Maruyama, Shigeo

    A molecular dynamics study of metal coating on SWNT Teppei Matsuo, Junichiro Shiomi and Shigeo-8656, Japan Metal coating on an SWNT is an important element technology in CNT-based electric and thermal device integrations. With the strong motivation, vacuum-evaporation experiments of various metals onto

  5. EMISSION SPECTRAL CONTROL USING METAL-COATED SILICON MICROCAVITY FOR THERMOPHOTOVOLTAIC

    E-print Network

    Kasagi, Nobuhide

    using two different metal deposition methods, electron-beam evaporation and vacuum arc evaporation. Surface roughness of the metal coating with vacuum arc evaporation is much smaller than that with electron to the designed value. However, for microcavities with vacuum-arc-evaporated metal coatings, the emittance

  6. Nanocrystalline spin coated sol-gel hydroxyapatite thin films on Ti substrate: Towards potential applications for implants

    NASA Astrophysics Data System (ADS)

    Carradò, Adele; Viart, Nathalie

    2010-07-01

    Sol-gel spin coating is a promising process to obtain hydroxyapatite (HA) thin films. It is an alternative route to the hydroxyapatite deposition techniques usually employed to cover orthopaedic or dental titanium implant surfaces. The sol-gel (SG) parameters leading to a pure and crystalline HA coatings on Ti substrate were determined. They allow to reach a stoichiometric hydroxyapatite composition (ideal Ca/P atomic ratio 1.67) and a control of the growth of the crystalline phases. The samples, when observed by Scanning Electron Microscopy (SEM), exhibit grains of ca. 200 nm, well adapted for cell proliferation. The crystallisation of the HA films was thoroughly studied by X-Ray diffraction (XRD). The aim of this paper is to validate the sol-gel method as a processing method allowing the control of the mechanical state of the films and, in particular, of the residual stresses (RS) at metal-ceramic interfaces. These stresses were determined on titanium substrates. While the uncoated Ti substrates were in a compressive residual state, the coated ones were in a low tensile state. These results suggest that the sol-gel process is indeed a processing route to obtain HA coated Ti implants.

  7. Soybean oil in water-borne coatings and latex film formation study by AC impedance

    Microsoft Academic Search

    Nantana Jiratumnukul

    1999-01-01

    Conventional coalescing agents such as butyl cellosolve, butyl carbitol, and TexanolRTM are widely use in the latex coatings industry to facilitate film formation at ambient temperature. Coalescent aids are composed of solvents with low evaporation rates. After water evaporates, coalescent aids would help soften polymer molecules and form continuous films, then gradually evaporates from the film. Coalescent aids, therefore, are

  8. Supercritical-carbon dioxide-assisted cyclic deposition of metal oxide and metal thin films

    E-print Network

    Gougousi, Theodosia

    Supercritical-carbon dioxide-assisted cyclic deposition of metal oxide and metal thin films Dipak are of interest in mi- croelectronics for potential applications in advanced metal- oxide-semiconductor transistor 2006 Thin films of aluminum oxide and palladium were deposited on silicon at low temperatures 70­120 °C

  9. High-barrier coated bacterial cellulose nanowhiskers films with reduced moisture sensitivity.

    PubMed

    Martínez-Sanz, Marta; Lopez-Rubio, Amparo; Lagaron, Jose M

    2013-10-15

    This study reports on the development and characterization of bacterial cellulose (BCNW) films coated with hydrophobic layers, presenting enhanced barrier properties. Pure BCNW films showed good transparency and thermal stability, high rigidity and extremely low oxygen permeability at 0%RH. The dramatic increase in oxygen permeability at 80%RH, due to the hydrophilic character of BCNW, was counteracted through coating the films with annealed PLA electrospun nanostructured fibres or hydrophobic silanes. The use of electrospinning was crucial to attain a good adhesion between the hydrophilic BCNW and the hydrophobic PLA layer. After electrospinning, the fibres were homogenised by annealing, thus obtaining a uniform and continuous coating. Coated systems showed a hydrophobic surface and protected the BCNW from moisture, thus reducing ca. 70% the water permeability and up to 97% the oxygen permeability at 80%RH. Furthermore, this novel approach was seen to protect BCNW films from moisture more efficiently than coating with hydrophobic silanes. PMID:23987449

  10. Ablation of transition metal oxides by different laser pulse duration and thin films deposition

    NASA Astrophysics Data System (ADS)

    Giardini Guidoni, A.; Flamini, C.; Varsano, F.; Ricci, M.; Teghil, R.; Marotta, V.; Di Palma, T. M.

    2000-02-01

    Thin films of transition metal oxides are of interest in many applications such as anticorrosion coatings and optical and electrochromic devices. In this work, the effect of different wavelength and pulse duration on ablation of oxides target has been investigated. The plume has been characterized by mass spectrometry and optical spectroscopy. Ablation thresholds have been measured by detecting ion emission from the target and from the onset of the plume luminescence. Morphology and optical properties of thin films deposited in different conditions are presented.

  11. Vapor growth of electrochromic thin films of transition metal oxides

    Microsoft Academic Search

    K. A. Gesheva; T. Ivanova; B. Marsen; G. Zollo; M. Kalitzova

    2008-01-01

    Mixed oxide films of transition metals gain considerable much attention due to their interesting optoelectronic properties. The low temperature chemical vapor growth processing of thin films of mixed W and Mo oxides is presented. The investigation is related to optimization of films structure and the related optoelectronic properties in dependence on the chemical vapor deposition (CVD) process parameters. Their electrochromic

  12. A High-Performance Polycrystalline Silicon Thin-Film Transistor Using Metal-Induced Crystallization with Ni Solution

    Microsoft Academic Search

    Soo Young Yoon; Sung Ki Kim; Jae Young Oh; YoungJin Choi; Woo Sung Shon; Chae Jang; J. Jang

    1998-01-01

    A new fabrication process for polycrystalline silicon (poly-Si) thin-film transistors (TFTs) on glass substrate is reported. Amorphous silicon (a-Si) was crystallized by metal-induced crystallization (MIC) using a Ni solution for low-temperature crystallization. The a-Si film spin-coated with a 5000 ppm Ni solution was fully crystallized at 500° C. The poly-Si TFT made of the poly-Si exhibited a field-effect mobility of

  13. Environmental Effects on Subcritical Delamination of Dielectric and Metal Films from Organosilicate Glass (OSG) Thin Films

    E-print Network

    films may be vulnerable to stress-corrosion, leading to delamination of the film stack. To better with 150 nm of Cu; the SiNx and SiO2 wafers were coated with a 70 nm adhesion layer of Ti, followed by 300 nm of Cu. Four-point-bend samples were prepared by bonding these wafers to SiNx-coated silicon wafers

  14. Osmium conductive metal coating for SEM specimen using sublimated osmium tetroxide in negative glow phase of DC glow discharge.

    PubMed

    Tanaka, A

    1994-08-01

    A new method of osmium conductive metal coating for scanning electron microscopy specimens using osmium tetroxide in direct current glow discharge and its apparatus have been devised. Anode and cathode plates are placed in a gas reactor, sublimated osmium tetroxide is introduced, and glow discharge is generated. As a result, the gas between the electrodes instantaneously becomes plasma. At the specimen surface, which is placed in the negative glow phase on the cathode plate, positively ionized osmium molecules are directly adhered and deposited, thereby leaving a completely amorphous metal coating of osmium. As a result, the formed coating precisely matched the fine structure of the specimen surface, and even when irradiated with a strong electron beam was free of heat damage, electrification and contamination. The secondary electron emission efficiency of the coating was also good. Furthermore, no granularity of the film surface was observed even when viewed at a high magnification. In this way, a superior osmium conductive metal coating was obtained. PMID:7996076

  15. Preparation of chitosan-coated polyethylene packaging films by DBD plasma treatment.

    PubMed

    Theapsak, Siriporn; Watthanaphanit, Anyarat; Rujiravanit, Ratana

    2012-05-01

    Polyethylene (PE) packaging films were coated with chitosan in order to introduce the antibacterial activity to the films. To augment the interaction between the two polymers, we modified the surfaces of the PE films by dielectric barrier discharge (DBD) plasma before chitosan coating. After that the plasma-treated PE films were immersed in chitosan acetate solutions with different concentrations of chitosan. The optimum plasma treatment time was 10 s as determined from contact angle measurement. Effect of the plasma treatment on the surface roughness of the PE films was investigated by atomic force microscope (AFM) while the occurrence of polar functional groups was observed by X-ray photoelectron spectroscope (XPS) and Fourier transformed infrared spectroscope (FTIR). It was found that the surface roughness as well as the occurrence of oxygen-containing functional groups (i.e., C?O, C-O, and -OH) of the plasma-treated PE films increased from those of the untreated one, indicating that the DBD plasma enhanced hydrophilicity of the PE films. The amounts of chitosan coated on the PE films were determined after washing the coated films in water for several number of washing cycles prior to detection of the chitosan content by the Kjaldahl method. The amounts of chitosan coated on the PE films were constant after washing for three times and the chitosan-coated PE films exhibited appreciable antibacterial activity against Escherichia coli and Staphylococcus aureus. Hence, the obtained chitosan-coated PE films could be a promising candidate for antibacterial food packaging. PMID:22512401

  16. In vitro corrosion behavior of bioceramic, metallic, and bioceramic–metallic coated stainless steel dental implants

    Microsoft Academic Search

    M. H Fathi; M Salehi; A Saatchi; V Mortazavi; S. B Moosavi

    2003-01-01

    Objectives: The most common metals and alloys used in dentistry may be exposed to a process of corrosion in vivo that make them cytotoxic. The biocompatibility of dental alloys is primarily related to their corrosion behavior. The aim of this work was to evaluate the corrosion behavior and thus the biocompatibility of the uncoated and coated stainless steels and compare

  17. Enhanced electrochemical properties of fluoride-coated LiCoO2 thin films

    PubMed Central

    2012-01-01

    The electrochemical properties of fluoride-coated lithium cobalt oxide [LiCoO2] thin films were characterized. Aluminum fluoride [AlF3] and lanthanum fluoride [LaF3] coating layers were fabricated on a pristine LiCoO2 thin film by using a spin-coating process. The AlF3- and LaF3-coated films exhibited a higher rate capability, cyclic performance, and stability at high temperature than the pristine film. This indicates that the AlF3 and LaF3 layers effectively protected the surface of the pristine LiCoO2 film from the reactive electrolyte. PMID:22221488

  18. Thickness Measurement of Thin-metal Films by Optical Metrology

    Microsoft Academic Search

    V. K. Kamineni; M. Raymond; E. J. Bersch; B. B. Doris; A. C. Diebold

    2009-01-01

    Spectroscopic ellipsometry (SE) and resistivity measurements were used to characterize Nickel-metal films used for self-aligned silicidation process. Variable angle spectroscopic ellipsometer (VASE) in the VUV range of wavelengths was used to measure the thickness and optical properties of Nickel films. The thickness-dependent optical properties of thin-metal films are shown to be correlated to the change in electron relaxation time and

  19. An evaluation of process parameters to improve coating efficiency of an active tablet film-coating process.

    PubMed

    Wang, Jennifer; Hemenway, Jeffrey; Chen, Wei; Desai, Divyakant; Early, William; Paruchuri, Srinivasa; Chang, Shih-Ying; Stamato, Howard; Varia, Sailesh

    2012-05-10

    Effects of material and manufacturing process parameters on the efficiency of an aqueous active tablet film-coating process in a perforated pan coater were evaluated. Twenty-four batches representing various core tablet weights, sizes, and shapes were coated at the 350-500 kg scale. The coating process efficiency, defined as the ratio of the amount of active deposited on tablet cores to the amount of active sprayed, ranged from 86 to 99%. Droplet size and velocity of the coating spray were important for an efficient coating process. Factors governing them such as high ratios of the suspension spray rate to atomization air flow rate, suspension spray rate to pattern air flow rate, or atomization air flow rate to pattern air flow rate improved the coating efficiency. Computational fluid dynamics modeling of the droplets showed that reducing the fraction of the smaller droplets, especially those smaller than 10 ?m, resulted in a marked improvement in the coating efficiency. Other material and process variables such as coating suspension solids concentration, pan speed, tablet velocity, exhaust air temperature, and the length of coating time did not affect the coating efficiency profoundly over the ranges examined here. PMID:22301427

  20. Electron Dynamics in Transition Metal Granular Films

    NASA Astrophysics Data System (ADS)

    Massa, N. E.; Denardin, J. C.; Socolovsky, L. M.; Knobel, M.; Zhang, X. X.

    2007-03-01

    Near normal incidence reflectivity spectra of transition metal ˜500 nm thick cosputtered granular films on SiO2 subtracts were measured from 30 to 11000 cm-1 and at temperatures from 30 to 490 K. The reflectivity for Co0.85(SO2)0.15 has a frequency and temperature behavior according to conducting metal oxides. The electron scattering rate denotes an unique relaxation time characteristic of a single type of carriers and has a very strong temperature dependence due to strong electron-phonon interactions. Using small polaron fits we individualize these as related to glass stretching vibrational modes. The optical conductivity of Ni0.61(SO2)0.39, undergoing a metal-insulator transition at ˜77 K, has a Drude mode (freer carriers) and a mid-IR band (mid-infrared ``carriers''). This last disorder related strong resonance drives the phase transition by localization decreasing in magnitude as the temperature is lowered and points to a double relaxation process (two different scattering mechanisms). On the other hand, Co0.51(SO2)0.49 has an insulator reflectivity in which a distinctive band at ˜1450cm-1 originates in electron promotion, localization, and defect induced quasiparticle formation.

  1. Sol-gel antireflective coating on plastics

    DOEpatents

    Ashley, Carol S. (Albuquerque, NM); Reed, Scott T. (Albuquerque, NM)

    1990-01-01

    An antireflection film made from a reliquified sol-gel hydrolyzation, condensation polymeric reaction product of a silicon, alkoxides and/or metal alkoxides, or mixtures thereof. The film is particularly useful for coating plastics.

  2. Sol-gel antireflective coating on plastics

    DOEpatents

    Ashley, C.S.; Reed, S.T.

    1988-01-26

    An antireflection film made from reliquified sol-gel hydrolyzation, condensation polymeric reaction product of a silicon, alkoxides and/or metal alkoxides, or mixtures thereof. The film is particularly useful for coating plastics.

  3. Evaluation of Adhesive Behaviors of Chromium Nitride Coating Films Produced by Arc Ion Plating Method

    NASA Astrophysics Data System (ADS)

    Murakami, Ri-Ichi; Kim, Yun-Hae; Kimura, Kazushi; Yonekura, Daisuke; Shin, Do-Hoon

    Scratch tests and pin-on-disk wear tests were performed to clarify the cracking and delaminating behavior of CrN coatings. The CrN films were coated onto an aluminum alloy substrate, JIS A2024, by an arc ion plating method. Eight types of single-layered coating and multilayered coatings were prepared by changing the bias voltage during the deposition. LCI and LCII values were not improved by increasing the number of layers. The critical loads of the single-layered coatings decreased with increasing the bias voltage. It appears that, for the multilayered coatings, the combination of bias voltages influenced the critical loads. The critical loads strongly depended on dynamic hardness and Young’s modulus. In particular, the critical loads of the multilayered coatings were influenced by the properties of the intermediate and bottom layers as well as the surface roughness, hardness and Young’s modulus of the top layer. The large film delamination for single-layered coatings deposited using a high bias voltage occurred during pin-on-disk wear tests even though the critical loads of the single-layered coatings were higher than those of the multilayered coatings. If the brittle top layer could be broken and delaminated by the sliding contact, the ductile bottom layer coated under a bias voltage of 0V could endure the complete delamination of film.

  4. Subwavelength metal grating metamaterial for polarization selective optical antireflection coating

    E-print Network

    Kim, Wonkyu; Hendrickson, Joshua

    2015-01-01

    A metamaterial structure consisting of a one-dimensional metal/air-gap subwavelength grating is investigated for optical antireflection coating on germanium substrate in the infrared regime. For incident light polarized perpendicularly to the grating lines, the metamaterial exhibits effective dielectric property and Fabry-Perot like plasmon-coupled optical resonance results in complete elimination of reflection and enhancement of transmission. It is found that the subwavelength grating metamaterial antireflection structure does not require a deep subwavelength grating period, which is advantageous for device fabrication. Maximal transmittance of 93.4% with complete elimination of reflection is seen in the mid-wave infrared range.

  5. A study of Nafion-coated and uncoated thin mercury film-rotating disk electrodes for cadmium and lead speciation in model solutions of fulvic acid

    Microsoft Academic Search

    J. Murimboh; Michael T. Lam; Nouri M. Hassan; C. L. Chakrabarti

    2000-01-01

    The speciation of lead and cadmium in model solutions of a well characterized fulvic acid (FA), Laurentian FA, was investigated by anodic stripping voltammetry (ASV) using a thin mercury film-rotating disk electrode (TMF-RDE) and a Nafion-coated TMF-RDE. Pseudopolarograms were fitted to a model that accounted for differences in the diffusion coefficients between the free metal ion, M, and the metal

  6. Microstructural and superconducting properties of high current metal-organic chemical vapor deposition YBa2Cu3O7-delta coated conductor wires

    Microsoft Academic Search

    T. G. Holesinger; B. Maiorov; O. Ugurlu; L. Civale; Y. Chen; X. Xiong; Y. Xie; V. Selvamanickam

    2009-01-01

    Metal-organic chemical vapor deposition (MOCVD) on flexible, ion beam assisted deposition MgO templates has been used to produce high critical current density (Jc) (Y,Sm)1Ba2Cu3Oy (REBCO) films suitable for use in producing practical high temperature superconducting (HTS) coated conductor wires. Thick films on tape were produced with sequential additions of 0.7 µm of REBCO via a reel-to-reel progression through a custom-designed

  7. Metallic thin films for NEMS/MEMS: From fundamental behaviour to microstructural design and fabrication

    NASA Astrophysics Data System (ADS)

    Luber, Erik

    2011-07-01

    The main focus of this thesis is the study of thin metal films in microelectromechanical/ nanoelectromechanical systems (MEMS/NEMS), ranging from application to fundamental behaviour. The use of metallic structural components is desirable since they are electrically conductive, optically re ective and ductile. However, polycrystalline metallic thin films typically exhibit low strength and hardness, high surface roughness and significant incremental stress, making them unusable for NEMS/MEMS. By co-sputtering Ni-Mo thin films we are able to tailor the microstructure and surface morphology such that these limitations are overcome. As such, uncurled NEMS cantilevers possessing enhanced hardness, metallic conductivity and sub-nanometer roughness are fabricated with resonant frequencies in the MHz regime, and quality factors ranging from 200-900. Following this, the use and design of all-metal atomic force microscope (AFM) probes is investigated. This is motivated by the growing number of AFM applications which make use of metal-coated probes, and as a result of the metallization suffers from stress-induced cantilever bending, thermal expansion mismatch, increased tip radius and limited device lifetime due to coating wear. To this end, monostructural all-metal AFM probes having 1 ?m thickness, lengths of 100-400 ?m, and tip radii ranging from 10 to 40 nm are fabricated. This is accomplished through microstructural design of Cu-Hf thin films, where an optimal combination of resistivity (96 ??cm), hardness (5:2 GPa), ductility and incremental stress. Lastly, in many MEMS/NEMS applications the unique properties of nonmetallic components are required, but a metallization layer is still needed. As metallization layers become increasingly thinner, film stability can become problematic, due to the phenomenon of solid-state dewetting. The fundamental mechanisms of solid-state dewetting are investigated in Ni thin films on SiO2. This phenomenon is monitored in situ using time resolved differential reflectometry (TRDR) and ex situ using AFM. It is found that Ni dewetting on SiO2 occurs through the sequential processes of grain growth, grain boundary grooving, hole growth and particle coarsening. Kinetic analysis of the TRDR data revealed two rate-limiting processes, with activation energies of 0:31±0:04 and 0.59±00.6 eV. It is hypothesized that these kinetic pathways correspond to Ni grain growth and surface mass self-diffusion on the Ni(111) planes, respectively.

  8. Investigation of a methodology for in-film defects detection on film coated blank wafers

    NASA Astrophysics Data System (ADS)

    Kiyotomi, Akiko; Dauendorffer, Arnaud; Shimura, Satoru; Miyazaki, Shinobu; Miyagi, Takemasa; Ota, Shigeru; Haneda, Koji; Baris, Oksen; Wei, Junwei

    2014-04-01

    Multi-patterning is one of the commonly used processes to shrink device node dimensions. With the miniaturization of the device node and the increasing number of coated layers and lithography processes, needs for defect reduction and control are getting stronger. Although there are needs for detecting in-film defects during the lithography process, it is difficult to verify in-film defects detected by an optical inspection tool because in-film defects usually appear as SEM Non-Visuals (SNV) during defect review using a scanning electron microscope (SEM). This makes the tuning of optical inspection tools difficult since these defects may be considered as noise. However, if these defects are "real defects", they will have a negative impact to manufacturing yield. In this paper, we investigate a new methodology to detect in-film defects with high sensitivity utilizing a broadband plasma inspection tool. This methodology is expected to allow the early detection of in-film defects before the pattern formation, hence improving device manufacturing yield.

  9. Ellipsometry study on gold-nanoparticle-coated gold thin film for biosensing application

    PubMed Central

    Moirangthem, Rakesh Singh; Chang, Yia-Chung; Wei, Pei-Kuen

    2011-01-01

    The amplified plasmonic response from various distributions of gold nanoparticles (AuNPs) coated on top of gold thin film was studied via ellipsometry under total internal reflection mode. The surface plasmon resonance dip can be tuned from the visible to near infrared by simply varying the AuNP concentration. Theoretical modeling based on effective medium theory with a multi-slice model has been employed to fit the experimental results. Additionally, this experimental tool has been further extended to study bio-molecular interactions with metal surfaces as well as in studying protein-protein interaction without any labeling. Hence, this technique could provide a non-destructive way of designing tunable label-free optical biosensors with very high sensitivity. PMID:21991549

  10. Thin casein films as prepared by spin-coating: influence of film thickness and of pH.

    PubMed

    Müller-Buschbaum, P; Gebhardt, R; Maurer, E; Bauer, E; Gehrke, R; Doster, W

    2006-06-01

    Casein films were successfully prepared with the spin-coating technique of aqueous casein solutions on base-treated glass surfaces. The film structure is investigated in real space with optical microscopy and atomic force microscopy and for the first time in reciprocal space with grazing incidence small-angle X-ray scattering (GISAXS). The size of the substructures detected in the film increases with pH from 170 nm (pH 5.1) up to 490 nm (pH 9.4). Dynamic light scattering experiments reveal that the average diameters of casein micelles in solution exhibit the same quantitative increase. This result suggests that the substructures detected in the bulklike films with GISAXS reflect intact casein micelles. However, with thin homogeneous casein films, the micelle size diminishes with decreasing film thickness. This indicates that the moderate pressures introduced by spin-coating force the micelles to rearrange into a more compact structure. PMID:16768397

  11. Pentek metal coating removal system: Baseline report; Summary

    SciTech Connect

    NONE

    1997-07-31

    The Pentek metal coating removal system consists of the ROTO-PEEN Scaler, CORNER-CUTTER(R), and VAC-PAC(R). The system is designed to remove coatings from steel, concrete, brick, and wood. The Scaler uses 3M ROTO-PEEN tungsten carbide cutters, while the CORNER-CUTTER(R) uses solid needles for descaling activities. These are used with the VAC-PAC(R) vacuum system to capture dust and debris as removal of the coating takes place. The safety and health evaluation during the testing demonstration focused on two main areas of exposure: dust and noise. Dust exposure was minimal, but noise exposure was significant. Further testing for each exposure is recommended, since the outdoor environment where the testing demonstration took place may skew the results. It is feasible that dust and noise levels will be higher in an enclosed operating environment. Other areas of concern found were arm-hand vibration, whole-body vibration, ergonomics, heat stress, tripping hazards, electrical hazards, machine guarding, and lockout/tagout.

  12. The biocompatibility of the tantalum and tantalum oxide films synthesized by pulse metal vacuum arc source deposition

    NASA Astrophysics Data System (ADS)

    Leng, Y. X.; Chen, J. Y.; Yang, P.; Sun, H.; Wang, J.; Huang, N.

    2006-01-01

    The surface modification technique is extensively employed to improve and control biocompatibility for blood and cell attachment. In this paper, tantalum thin films were synthesized by pulsed metal vacuum arc source deposition, the tantalum oxide films were fabricated by tantalum films heated at 700 °C for 1 h in air. The films were characterized using X-ray diffraction (XRD). In vitro investigations of cultured human umbilical vein endothelial cells (HUVEC) on Ta, tantalum oxide films, 316L stainless steel and CP-Ti revealed that the growth and proliferation behavior of endothelial cells on the sample surfaces varied significantly. The adherence, growth, shape and proliferation of endothelial cells on tantalum and tantalum oxide films were much better than 316L stainless steel and CP-Ti. The Ta and tantalum oxide films shown to fulfill the requirements necessary for the application as a blood-contacting device (such as stent) coating.

  13. Patterning microconductor using nanosecond laser ablation of metal nanoparticle film

    NASA Astrophysics Data System (ADS)

    Han, Sewoon; Lim, Taewong; Chung, Jaewon; Ko, Seung H.; Grigoropoulos, Costas P.; Kim, Dongjo; Moon, Jooho

    2007-02-01

    Ablation of metal nanoparticle film using frequency doubled Nd:YAG nanosecond laser is explored to apply for trimming drop on demand (DOD) inkjet printed electrical micro-conductor for flexible electronics. While elevated rim structure due to expulsion of molten pool is observed in sintered nanoparticle film, the ablation of unsintered nanoparticle film results in a Gaussian-shaped ablation profile, so that a clean precise patterning is possible. In addition, the ablation fluence threshold of unsintered metal nanoparticle film is at least ten times lower than that of a corresponding metal film. Therefore, by using nanosecond laser ablation, inkjet printed metal nanoparticles compatible for flexible polymer can be patterned efficiently with a high resolution.

  14. Deposition of alloy films. [on irregulary shaped metal object

    NASA Technical Reports Server (NTRS)

    Spalvins, T. (inventor)

    1973-01-01

    An invention is described which deposits metal alloy films on a metal object. A glow discharge is established by applying a high voltage between an anode and a cathode object disposed in an inert gas atmosphere. An alloy of two or more metals is vaporized and the vapor injected into the glow discharge causing the alloy to be plated onto the cathode object.

  15. Solid film lubricants and thermal control coatings flown aboard the EOIM-3 MDA sub-experiment

    NASA Technical Reports Server (NTRS)

    Murphy, Taylor J.; David, Kaia E.; Babel, Hank W.

    1995-01-01

    Additional experimental data were desired to support the selection of candidate thermal control coatings and solid film lubricants for the McDonnell Douglas Aerospace (MDA) Space Station hardware. The third Evaluation of Oxygen Interactions With Materials Mission (EOIM-3) flight experiment presented an opportunity to study the effects of the low Earth orbit environment on thermal control coatings and solid film lubricants. MDA provided five solid film lubricants and two anodic thermal control coatings for EOIM-3. The lubricant sample set consisted of three solid film lubricants with organic binders one solid film lubricant with an inorganic binder, and one solid film lubricant with no binder. The anodize coating sample set consisted of undyed sulfuric acid anodize and cobalt sulfide dyed sulfuric acid anodize, each on two different substrate aluminum alloys. The organic and inorganic binders in the solid film lubricants experienced erosion, and the lubricating pigments experienced oxidation. MDA is continuing to assess the effect of exposure to the low Earth orbit environment on the life and friction properties of the lubricants. Results to date support the design practice of shielding solid film lubricants from the low Earth orbit environment. Post-flight optical property analysis of the anodized specimens indicated that there were limited contamination effects and some atomic oxygen and ultraviolet radiation effects. These effects appeared to be within the values predicted by simulated ground testing and analysis of these materials, and they were different for each coating and substrate.

  16. Bio-functional nano-coatings on metallic biomaterials.

    PubMed

    Mahapatro, Anil

    2015-10-01

    Metals and their alloys have been widely used in all aspects of science, engineering and medicine. Metals in biomedical devices are used due to their inertness and structural functions. They are generally preferred over polymers or ceramics and are especially desirable in applications where the implants are subjected to static, dynamic or cyclic loads that require a combination of strength and ductility. In biomedicine, the choice of a specific biomaterial is governed by many factors that include biocompatibility, corrosion resistance, controlled degradability, modulus of elasticity, fatigue strength and many other application specific criterions. Nanotechnology is driving newer demands and requirements for better performance of existing materials and presents an opportunity for surface modification of metals in response to demands on the surface of metals for their biomedical applications. Self-assembled monolayers (SAMs) are nanosized coatings that present a flexible method of carrying out surface modification of biomaterials to tailor its surface properties for specific end applications. These nanocoatings can serve primary functions such as surface coverage, etch protection and anti-corrosion along with a host of other secondary chemical functions such as drug delivery and biocompatibility. We present a brief introduction to surface modification of biomaterials and their alloys followed by a detailed description of organic nanocoatings based on self-assembled monolayers and their biomedical applications including patterning techniques and biological applications of patterned SAMs. PMID:26117759

  17. Chemical vapor deposition thin films as biopassivation coatings and directly patternable dielectrics

    E-print Network

    Pryce Lewis, Hilton G. (Hilton Gavin), 1973-

    2001-01-01

    Organosilicon thin films deposited by pulsed plasma-enhanced chemical vapor deposition (PPECVD) and hot-filament chemical vapor deposition (HFCVD) were investigated as potential biopassivation coatings for neural probes. ...

  18. Evaluation of polyelectrolyte multilayer thin-film coated microneedle arrays for transcutaneous vaccine delivery

    E-print Network

    Fung, Peter W. (Peter Waitak)

    2011-01-01

    The skin is an ideal organ for the safe and convenient delivery of vaccines, small molecules, and other biologics. Members of the Irvine and Hammond groups have developed a polyelectrolyte multilayer thin film-coated ...

  19. Oxide film on metal substrate reduced to form metal-oxide-metal layer structure

    NASA Technical Reports Server (NTRS)

    Youngdahl, C. A.

    1967-01-01

    Electrically conductive layer of zirconium on a zirconium-oxide film residing on a zirconium substrate is formed by reducing the oxide in a sodium-calcium solution. The reduced metal remains on the oxide surface as an adherent layer and seems to form a barrier that inhibits further reaction.

  20. Study of double layer rare earth metal conversion coating on aluminum alloy LY12

    Microsoft Academic Search

    Yu Xingwen; Cao Chunan; Yao Zhiming; Zhou Derui; Yin Zhongda

    2001-01-01

    The process of the double layer rare earth metal (REM) conversion coating on aluminum alloy LY12 (2024) was introduced in this paper. The corrosion resistance of REM conversion coating was examined by electrochemical impedance spectroscopy. The results showed that the coating increased the corrosion resistance (Rp) of the alloy surface, thus reducing the driving force of corrosion. The morphologies of

  1. Dissipation of micro-cantilevers as a function of air pressure and metallic coating

    E-print Network

    Paris-Sud XI, Université de

    when viscous dissipation van- ishes in vacuum. Understanding the source of this coating inducedepl draft Dissipation of micro-cantilevers as a function of air pressure and metallic coating T. J characterize the internal dissipation of coated micro-cantilevers through their mechanical thermal noise. Using

  2. Properties of two biological glasses used as metallic prosthesis coatings and after an implantation in body

    E-print Network

    Paris-Sud XI, Université de

    Properties of two biological glasses used as metallic prosthesis coatings and after an implantation a biomaterial coating. A layer thickness of few tens of micrometers allows to isolate the implant from-chemical techniques. The implant with its coating is in contact either with trabecular bone or with lacuna site

  3. Fly ash based geopolymer thin coatings on metal substrates and its thermal evaluation

    Microsoft Academic Search

    Jadambaa Temuujin; Amgalan Minjigmaa; William Rickard; Melissa Lee; Iestyn Williams; Arie van Riessen

    2010-01-01

    Class F fly ash based Na-geopolymer formulations have been applied as fire resistant coatings on steel. The main variables for the coating formulations were Si: Al molar and water: cement weight ratios. We have determined that the adhesive strength of the coatings strongly depend on geopolymer composition. The ease with which geopolymer can be applied onto metal surfaces and the

  4. Bismuth film electrodes for heavy metals determination

    NASA Astrophysics Data System (ADS)

    Rehacek, Vlastimil; Hotovy, Ivan; Vojs, Marian; Mika, Fedor

    2007-05-01

    Bismuth film electrodes (BiFEs) have a potential to replace toxic mercury used most frequently for determination of heavy metals (Cd, Pb, Zn) by anodic stripping voltammetry. We prepared a graphite disc electrode (0.5 mm in diameter) from a pencil-lead rod and developed a nitrogen doped diamond-like carbon (NDLC) microelectrode array consisting of 50 625 microdiscs with 3 ?m in diameter and interelectrode distances of 20 ?m on a highly conductive silicon substrate as a support for BiFEs. The disc graphite BiFE was used for simultaneous determination of Pb(II), Cd(II) and Zn(II) by square wave voltammetry (SWV) in an aqueous solution. We found the optimum bismuth-to-metal concentration ratio in the solution to be 20. The dependence of the stripping responses on the concentration of target metals was linear in the range from 1×10 -8 to 1.2×10 -7 mol/L. Detection limits 2.4×10 -9 mol/L for Pb(II), 2.9×10 -9 mol/L for Cd(II) and 1.2×10 -8 mol/L for Zn(II) were estimated. A bismuth-plated NDLC microelectrode array was used for Pb(II) determination by differential pulse voltammetry (DPV) in an aqueous solution. We found that the stripping current for bismuth-plated NDLC array was linear in the concentration range of Pb(II) from 2×10 -8 to 1.2×10 -7 mol/L. The detection limit 2.2×10 -8 mol/L was estimated from a calibration plot.

  5. Thermoelastic response of thin metal films and their adjacent materials

    SciTech Connect

    Kang, S.; Yoon, Y.; Kim, J.; Kim, W. [Samsung Electronics Co., Yongin-Si, 446-712 Gyeonggi-do (Korea, Republic of)] [Samsung Electronics Co., Yongin-Si, 446-712 Gyeonggi-do (Korea, Republic of)

    2013-01-14

    A pulsed laser beam applied to a thin metal film is capable of launching an acoustic wave due to thermal expansion. Heat transfer from the thin metal film to adjacent materials can also induce thermal expansion; thus, the properties of these adjacent materials (as well as the thin metal film) should be considered for a complete description of the thermoelastic response. Here, we show that adjacent materials with a small specific heat and large thermal expansion coefficient can generate an enhanced acoustic wave and we demonstrate a three-fold increase in the peak pressure of the generated acoustic wave on substitution of parylene for polydimethylsiloxane.

  6. Super elastic strain limit in metallic glass films

    PubMed Central

    Jiang, Q. K.; Liu, P.; Ma, Y.; Cao, Q. P.; Wang, X. D.; Zhang, D. X.; Han, X. D.; Zhang, Z.; Jiang, J. Z.

    2012-01-01

    On monolithic Ni-Nb metallic glass films, we experimentally revealed 6.6% elastic strain limit by in-situ transmission electron microscopy observations. The origin of high elastic strain limit may link with high free volume in the film, causing the rearrangement of loosely bonded atomic clusters (or atoms) upon elastic deformation. This high elastic limit of metallic glass films will shed light on new application fields for metallic glasses, and also trigger more studies for deformation mechanism of amorphous materials in general. PMID:23152943

  7. Thermal annealing effects on chemical states of deuterium implanted into boron coating film

    Microsoft Academic Search

    H. Kodama; T. Sugiyama; Y. Morimoto; Y. Oya; K. Okuno; N. Inoue; A. Sagara; N. Noda

    2003-01-01

    To reveal interaction between boron coating film and energetic hydrogen isotopes, chemical states of deuterium implanted into the boron coating films deposited on graphite by using DC glow discharge in a diborane diluted helium have been studied. The XPS measurements showed the possibility of the formation of B–D and C–D bonds by D2+ ion implantation. The TDS experiments indicated that

  8. The Use of Electric Fields for Edible Coatings and Films Development and Production: A Review

    Microsoft Academic Search

    Bartolomeu W. S. Souza; Miguel A. Cerqueira; José A. Teixeira; António A. Vicente

    2010-01-01

    Edible films and coatings can provide additional protection for food, while being a fully biodegradable, environmentally friendly\\u000a packaging system. A diversity of raw materials used to produce edible coatings and films are extracted from marine and agricultural\\u000a sources, including animals and plants. Electric fields processing holds advantage in producing safe, wholesome and nutritious\\u000a food. Recently, the presence of a moderate

  9. Characteristics of thin cellulose ester films spin-coated from acetone and ethyl acetate solutions

    Microsoft Academic Search

    J. Amim Jr; P. M. Kosaka; D. F. S. Petri

    2008-01-01

    Spin-coated films of cellulose acetate (CA), cellulose acetate propionate (CAP), cellulose acetate butyrate (CAB) and carboxymethylcellulose\\u000a acetate butyrate (CMCAB) have been characterized by ellipsometry, atomic force microscopy (AFM) and contact angle measurements.\\u000a The films were spin-coated onto silicon wafers, a polar surface. Mean thickness values were determined by means of ellipsometry\\u000a and AFM as a function of polymer concentration in

  10. Tackiness of acrylic and cellulosic polymer films used in the coating of solid dosage forms

    Microsoft Academic Search

    Martin Wesseling; Frank Kuppler; Roland Bodmeier

    1999-01-01

    The objective was to determine the tackiness of acrylic and cellulosic polymer films in order to make predictions on the tackiness (agglomeration) of coated dosage forms during coating and curing. Force-displacement curves of the detachment process of two polymeric films were used as a measure of tackiness. Various polymers (cellulosic (Aquacoat®) and acrylics (Eudragit® RS 30D, L 30D, NE 30D)),

  11. OPTICAL COATINGS OF CVD-TRANSITION METAL OXIDES AS FUNCTIONAL LAYERS IN \\

    Microsoft Academic Search

    K. A. Gesheva; T. Ivanov; F. Hamelmann

    The paper presents the recent study on the technology and investigation of thin metal oxide films based on transition metals, such as W and Mo. Defined is the application aspect of the research, by describing the optical systems based on these films, namely the electrochromic device and the X-ray mirror. Results on the optical absorption in the films are presented,

  12. The structure of ion plated films in relation to coating properties

    NASA Technical Reports Server (NTRS)

    Spalvins, T.

    1985-01-01

    Ion plating is an ion assisted or glow discharge deposition technique, where ions or energetic atoms transfer energy, momentum and charge to the substrate and the growing film in a manner which can be controlled to favorably modify surface, subsurface chemistry, and microstructure. The glow discharge energizing effects from the initial nucleation stages to the final film growth are discussed. As a result, adherence, coherence, internal stresses, density and morphology of the coatings are significantly improved, over the conventional (nonion-assisted) techniques which in turn favorably affect the surface initiated failures caused by friction, wear, erosion, corrosion and fatigue. Ion plated films because of their graded coating/substrate interface, fine, uniform, densely packed film structure also induce a surface strengthening effect which improved the mechanical properties such as yield, tensile strength and fatigue life. Since a uniform, continuous film can be obtained at lower nominal film thickness, this effect is of great importance in solid film lubrication and in corrosion protection.

  13. Spin coated unsubstituted copper phthalocyanine thin films for nitrogen dioxide sensors

    NASA Astrophysics Data System (ADS)

    Chakane, Sanjay; Datir, Ashok; Koinkar, Pankaj

    2015-03-01

    Copper phthalocyanine (CuPc) is synthesized chemically and used for making CuPc thin films using spin coating technique. Films were prepared from trifluroacetic acid (TFA) and chlorobenzene mixed solution on the glass substrate. Spin coated films of unsubstituted CuPc films were heat annealed at 150°C for 2 h duration and were used to study NO2 gas sensing characteristics. ?-phase of CuPc is noted by UV-visible absorption spectra. IR spectra of undoped CuPc films and doped CuPc films with NO2 revealed that, doping of nitrogen dioxide modifies and deletes some of the bands. The effect of NO2 at various concentrations from 50 ppm to 500 ppm in atmospheric air at room temperature on the electrical conductivity of CuPc films was studied. Sensitivity, response time and repeatability of the CuPc sensor were discussed in this paper.

  14. Photoactivated chlorophyllin-based gelatin films and coatings to prevent microbial contamination of food products.

    PubMed

    López-Carballo, G; Hernández-Muñoz, P; Gavara, R; Ocio, M J

    2008-08-15

    The aim of this work was to develop antimicrobial photosensitizer-containing edible films and coatings based on gelatin as the polymer matrix, incorporating sodium magnesium chlorophyllin (E-140) and sodium copper chlorophyllin (E-141). Chlorophyllins were incorporated into the gelatin film-forming solution and the inhibiting effect of the cast films was tested against Staphylococcus aureus and Listeria monocytogenes. The results demonstrated that water soluble sodium magnesium chlorophyllin and water soluble sodium copper chlorophyllin reduced the growth of S. aureus and L. monocytogenes by 5 log and 4 log respectively. Subsequently, the activity of self-standing films and coatings containing E-140 was assessed on cooked frankfurters inoculated with S. aureus and L. monocytogenes. These tests showed that it was possible to reduce microorganism growth in cooked frankfurters inoculated with S. aureus and L. monocytogenes by covering them with sodium magnesium chlorophyllin-gelatin films and coatings. PMID:18555550

  15. Low earth orbit environmental effects on osmium and related optical thin-film coatings

    Microsoft Academic Search

    T. R. Gull; Howard Herzig; J. F. Osantowski; A. R. Toft

    1985-01-01

    A number of samples of optical thin film materials were flown on Shuttle flight STS-8 as part of an experiment to evaluate their interaction with residual atomic oxygen in low earth orbit. Osmium was selected because of its usefulness as a reflective optical coating for far-UV instruments and for confirmation of results from previous Shuttle flights in which such coatings

  16. Undercutting of defects in thin film protective coatings on polymer surfaces exposed to atomic oxygen

    Microsoft Academic Search

    S. K. Rutledge; J. A. Mihelcic

    1989-01-01

    Protection for polymeric surfaces is needed to make them durable in the low Earth orbital environment, where oxidation by atomic oxygen is the predominant failure mechanism. Thin film coatings of oxides such as silicon dioxide are viable candidates to provide this protection, but concern has been voiced over the ability of these coatings to protect when defects are present in

  17. Atomic force microscopy (AFM) morphological surface characterization of transparent gas barrier coatings on plastic films

    Microsoft Academic Search

    G. Garcia-Ayuso; L. Vázquez; J. M. Martínez-Duart

    1996-01-01

    The relationship between the surface morphology and water vapor diffusivity of barrier coatings on polymeric polyethylene terephthalate (PET) films is studied by atomic force microscopy. The coatings, composed of aluminum oxide and\\/or silicon oxide, were grown by various deposition methods. It is observed that no correlation exists when the surface roughness is measured over large scanned areas owing to the

  18. Bioequivalence study of 400 and 100 mg imatinib film-coated tablets in healthy volunteers.

    PubMed

    Ostrowicz, Andrzej; Miko?ajczak, Przemys?aw L; Wierzbicka, Marzena; Boguradzki, Piotr

    2014-01-01

    The aim of the study was to investigate the bioavailability of a generic product of 100 mg and 400 mg imatinib film-coated tablets (test) as compared to that of a branded product (reference) at the same strength to determine bioequivalence. The secondary objective of the study was to evaluate tolerability of both products. An open-label, randomized, crossover, two-period, single-dose, comparative study was conducted in 43 (Imatynib-Biofarm 100 mg film-coated tablet) and in 42 (Imatynib-Biofarm 400 mg film-coated tablet), brand name Imatenil, Caucasian healthy volunteers in fed conditions. A single oral dose administration of the test or reference product was separated by 14-day washout period. The imatinib and its metabolite N-desmethyl imatinib concentrations were determined using a validated LC MS/MS method. The results of the single-dose study in healthy volunteers indicated that the film-coated tablets of Imatynib-Biofarm 100 mg and 400 mg film-coated tablets manufactured by Biofarm Sp. z o.o. (test products) are bioequivalent to those of Glivec 100 mg and 400 mg film-coated tablets manufactured by Novartis Pharma GmbH (reference products). Both products in the two doses of imatinib were well tolerated. PMID:25362813

  19. Structure and Function of Starch-Based Edible Films and Coatings

    Microsoft Academic Search

    Michael E. Kramer

    \\u000a Edible films and coatings satisfy a variety of needs and meet specific product challenges for a large number of food applications.\\u000a There is a general lack of agreement as to what constitutes a coating. A layer of seasoning on a snack or an oil spray applied\\u000a to a cracker or a baked product, are examples of edible coatings. Further examples

  20. Multilayer coatings on flexible substrates

    SciTech Connect

    Martin, P.M.; Affinito, J.D.; Gross, M.E.; Coronado, C.A.; Bennett, W.D.; Stewart, D.C.

    1995-04-01

    Thin-film optical and non-optical multilayer coatings are deposited onto flexible substrates using a vacuum web coater developed at Pacific Northwest Laboratory. The coater`s primary application is rapid prototyping of multilayer (1) polymer coatings, (2) polymer/metal coatings, (3) ceramic/metal coatings, and (4) hybrid polymer, ceramic, and metal coatings. The coater is fully automated and incorporates polymer evaporation and extrusion heads, high-rate magnetron sputtering cathodes, and e-beam evaporation sources. Polymer electrolytes are deposited by extrusion techniques. Flexible plastic, metal, and ceramic substrates can be coated using roll-to-roll or closed-loop configurations. Examples of multilayer optical coatings demonstrated to date are solar reflectors, heat mirrors, Fabry-Perot filters, and alpha particle sensors. Nonoptical coatings include multilayer magnetic metal/ceramic and lamellar composites.

  1. Surface Roughness Statistic Models of Metallized Coatings in Grinding Manufacturing System

    Microsoft Academic Search

    MIHAIELA ILIESCU; MIHNEA COSTOIU

    Metallizing process has known a continuous extent, lately, because of the sprayed coatings' intensive application into various industrial fields. Metallized coatings have very important wear or, corrosion resistance characteristics and, when used for repairing worn parts, the prescribed surface quality specifications can be obtained only by grinding, after thermal spraying. Statistic models of grinded surface roughness are useful, specially, for

  2. Temperature dependence of mechanical properties of isotropic conductive adhesive filled with metal coated polymer spheres

    Microsoft Academic Search

    Hoang-Vu Nguyen; Helge Kristiansen; Rolf Johannessen; Erik Andreassen; Andreas Larsson; Nils Hoivik; Knut E. Aasmundtveit

    2011-01-01

    An isotropic conductive adhesive (ICA) filled with metalcoated polymer spheres (MPS) has been studied as a novel approach to increase the flexibility, and hence the reliability, compared to the conventional metal-filled ICA. In this study, the effect of the metal coating on the die shear strength was investigated by comparing ICA materials with coated and uncoated polymer spheres. The other

  3. Electrical double layer and adhesive force in fatigue strength of metals coated with plastics

    Microsoft Academic Search

    K. Jamroziak; W. Jargulinski

    Purpose: Literature consists a lot of information concerning the issues of the fatigue endurance of metals coated with plastics. However few studies explicitly explain, what mechanisms decide on the increased fatigue endurance of metals coated with plastics. Therefore an expression is a purpose of the work on what a way increasing this fatigue endurance permanence is taking a place. Design\\/methodology\\/approach:

  4. Squeezed mode conversion in hybrid plasmon polariton waveguide using spin-coated silver film.

    PubMed

    Ha, Thi-Vu-Anh; Park, Hae-Ryeong; Son, Jung-Han; Lee, Myung-Hyun

    2012-07-01

    We designed, fabricated, and characterized a hybrid surface plasmon polariton waveguide (SPP_wg) for mode conversion. The 20-nm-thick silver SPP_wg was fabricated via spin-coating with an aqueous silver ionic complex solution. The structure of the SPP_wg consists of a straight Insulator-Metal-Insulator waveguide (IMl_wg), a lateral tapered Insulator-Metal-Insulator-Metal-Insulator waveguide (tapered_IMIMI_wg), and a straight IMIMI waveguide (IMIMI_wg). An s0 mode size of 12.90 microm x 8.08 microm at a 6-microm-wide IMI_wg was excited by a butt-coupling method at a wavelength of 1550 nm. The s0 mode was converted into an Ss0 mode size of 8.08 microm x 5.65 microm at a 3-microm-wide IMIMI_wg. The mode size was squeezed by approximately 2/3 via a 15-microm-long lateral tapered_IMIMI_wg with a 500-nm-thick central insulator. The coupling loss for mode conversion between the straight IMI_wg and the straight IMIMI_wg was 5.49 dB. The hybrid SPP_wg for mode conversion has the potential to bridge the gap between micron and sub-micron scales in nano plasmonic integrated circuits. In addition, the use of the spin coating method is very cost-effective because films are formed at a low temperature in a short period of time without the need for a vacuum system. PMID:22966593

  5. Metal matrix coated fiber composites and the methods of manufacturing such composites

    DOEpatents

    Weeks, J.K. Jr.; Gensse, C.

    1993-09-14

    A fiber coating which allows ceramic or metal fibers to be wetted by molten metals is disclosed. The coating inhibits degradation of the physical properties caused by chemical reaction between the fiber and the coating itself or between the fiber and the metal matrix. The fiber coating preferably includes at least a wetting layer, and in some applications, a wetting layer and a barrier layer between the fiber and the wetting layer. The wetting layer promotes fiber wetting by the metal matrix. The barrier layer inhibits fiber degradation. The fiber coating permits the fibers to be infiltrated with the metal matrix resulting in composites having unique properties not obtainable in pure materials. 8 figures.

  6. Conductive metal oxide film and method of making

    DOEpatents

    Windisch, Jr., Charles F. (Kennewick, WA); Exarhos, Gregory J. (Richland, WA)

    1999-01-01

    The present invention is a method for reducing a dopant in a film of a metal oxide wherein the dopant is reduced and the first metal oxide is substantially not reduced. The method of the present invention relies upon exposing the film to reducing conditions for a predetermined time and reducing a valence of the metal from a positive valence to a zero valence and maintaining atoms with a zero valence in an atomic configuration within the lattice structure of the metal oxide. According to the present invention, exposure to reducing conditions may be achieved electrochemically or achieved in an elevated temperature gas phase.

  7. New Approach to Ceramic/Metal-Polymer Multilayered Coatings for High Performance Dry Sliding Applications

    NASA Astrophysics Data System (ADS)

    Rempp, A.; Killinger, A.; Gadow, R.

    2012-06-01

    The combination of thermally sprayed hard coatings with a polymer based top coat leads to multilayered coating systems with tailored functionalities concerning wear resistance, friction, adhesion, wettability or specific electrical properties. The basic concept is to combine the mechanical properties of the hard base coating with the tribological or chemical abilities of the polymer top coat suitable for the respective application. This paper gives an overview of different types of recently developed multilayer coatings and their application in power transmission under dry sliding conditions. State of the art coatings for dry sliding applications in power transmission are mostly based on thin film coatings like diamond-like carbon or solid lubricants, e.g. MoS2. A new approach is the combination of thin film coatings with combined multilayer coatings. To evaluate the capability of these tribological systems, a multi-stage investigation has been carried out. In the first stage the performance of the sliding lacquers and surface topography of the steel substrate has been evaluated. In the following stage thermally sprayed hard coatings were tested in combination with different sliding lacquers. Wear resistance and friction coefficients of combined coatings were determined using a twin disc test-bed.

  8. Film condensation of liquid metals -- precision of measurement

    E-print Network

    Wilcox, Stanley James

    1969-01-01

    Major differences exist in results published by investigators of film condensation of liquid metal vapors. In particular, the reported dependence of the condensation coefficient on pressure has raised questions about both ...

  9. Ultrathin film deposition by liquid CO2 free meniscus coating-uniformity and morphology.

    PubMed

    Kim, Jaehoon; Novick, Brian J; Desimone, Joseph M; Carbonell, Ruben G

    2006-01-17

    Ultrathin organic films of sucrose octaacetate (SOA) were deposited on 12.5 cm diameter silicon wafer substrates using high-pressure free meniscus coating (hFMC) with liquid CO2 (l-CO2) as a coating solvent. The dry film thickness across the wafer and the morphology of deposited films were characterized as a function of coating conditions-withdrawal velocity, solution concentration, and evaporation driving force (deltaP). When no evaporation driving force was applied (deltaP = 0), highly uniform films were deposited with thickness in the range of 8-105 angstroms over the entire concentration range (3-11 wt%). Uniform films were also obtained at low concentrations (3-5 wt%) with a low evaporation driving force (deltaP = 0.0138 MPa). However, films deposited at medium to high concentrations (7-11 wt%) were thicker (110-570 angstroms) and less uniform, with larger nonuniformities at higher applied evaporation driving forces. Optical microscopy and atomic force microscopy (AFM) were used to characterize film morphology including drying defects and film roughness. Films deposited without evaporation had no apparent drying defects and very low root-mean-square (RMS) roughness (1.4-3.8 angstroms). Spinodal-like dewetting morphologies including holes with diameters in the range of 100-300 nm, and surface undulations were observed in films deposited at medium concentration (7 wt%) and low deltaP (0.0138-0.0276 MPa). At higher concentrations and higher evaporative driving forces, spinodal-like dewetting morphologies disappeared but concentric ring defect structures were observed with diameters in the range 20-125 microm. The film thickness and morphology of SOA films deposited from 1-CO2 hFMC were compared to those deposited from toluene and acetone under normal dip coating. Films deposited from l-CO2 hFMC were much thinner, more uniform, and exhibited much fewer drying defects and lower RMS roughness. PMID:16401113

  10. Influence of metal plasma ion implantation on photo-sensitivity of anatase TiO 2 thin films

    Microsoft Academic Search

    Da-Yung Wang; Hsiao-Cheng Lin; Chung-Chih Yen

    2006-01-01

    Nano-scale TiO2 thin films were synthesized by using sol–gel and spin-coating techniques on glass substrates for photo-catalytic applications. The Ti(IV) butoxide-based TiO2 thin films were optimized for transforming into the high-purity crystalline anatase phase when calcined at 500 °C. To further enhance the photo-catalysis sensitivity of TiO2 thin films for use in visible light environments, a metal plasma ion implantation process

  11. Production and characterisations of thin films deposited by a novel vacuum coating plant (VCP)

    Microsoft Academic Search

    Hakan Kockar; Turgut Meydan; Mursel Alper; Elif Gungor

    2006-01-01

    This paper reports a novel vacuum coating plant (VCP) system to prepare magnetic thin films. The first step of this extensive investigation was to evaporate and characterise simple iron films on various substrate in order to understand the process of deposition. The source material evaporated by a resistively heated furnace, which was position under the substrate within the VCP system,

  12. Fracture mechanics of diamond-like carbon (DLC) films coated on flexible polymer substrates

    Microsoft Academic Search

    Dai Tsubone; Terumitsu Hasebe; Aki Kamijo; Atsushi Hotta

    2007-01-01

    Diamond-like carbon (DLC) films have been widely used for many industrial applications due to their outstanding physical properties such as high hardness, wear resistance and biological compatibility. The DLC films coated on polymer substrates have also been extensively used and investigated because recently, quite a few applications for the use of these polymer–DLC composites have been proposed and actively discussed.

  13. Enhanced spin-dependent tunneling magnetoresistance in magnetite films coated by polystyrene

    Microsoft Academic Search

    Wendong Wang; Leszek Malkinski; Jinke Tang

    2007-01-01

    Hematite films were deposited by magnetron sputtering. A phase transformation from hematite to magnetite occurred when polystyrene (PS) coated hematite films were annealed above 200 °C in hydrogen flow. Giant negative magnetoresistance (MR) was observed with the best MR ratio of over 8% (at room temperature and in a field of 5.5 T) found in samples annealed at 230 °C.

  14. Spintronics in metal–insulator nanogranular magnetic thin films

    Microsoft Academic Search

    Hiroyasu Fujimori; Shigehiro Ohnuma; Nobukiyo Kobayashi; Tsuyosi Masumoto

    2006-01-01

    Magnetic and electrical properties of metal–insulator nanogranular thin films are overviewed, from the spintronics point of view, by presenting our recent results. (1) The metal-rich ferromagnetic ones possess ultrahigh-frequency (MHz–GHz) permeabilities ??, ??, mainly owing to large induced magnetic anisotropy field Hk. They are useful for various magnetic devices, such as thin-film inductors and noise suppressors. (2) The insulator-rich superpramagnetic

  15. Method of synthesizing metal doped diamond-like carbon films

    NASA Technical Reports Server (NTRS)

    Ueno, Mayumi (Inventor); Sunkara, Mahendra Kumar (Inventor)

    2003-01-01

    A method of synthesizing metal doped carbon films by placing a substrate in a chamber with a selected amount of a metalorganic compound. An electron cyclotron resonance is applied to the chamber in order to vaporize the metalorganic compound. The resonance is applied to the chamber until a metal doped carbon film is formed. The metalorganic compound is preferably selected from the group consisting of an organic salt of ruthenium, palladium, gold or platinum.

  16. Evenly distributed thin-film Ag coating on stainless plate by tricomponent Ag/silicate/PU with antimicrobial and biocompatible properties.

    PubMed

    Huang, Yi-Hsiu; Chen, Mark Hung-Chih; Lee, Bing-Heng; Hsieh, Kuo-Huang; Tu, Yuan-Kun; Lin, Jiang-Jen; Chang, Chih-Hao

    2014-11-26

    A tricomponent nanohybrid dispersion in water comprising silver nanoparticles (AgNP), nanometer-thick silicate platelets (NSP), and water-based polyurethane (PU) was developed for surface coating on orthopedic metal plates. The previously developed AgNP-on-NSP nanohybrid was homogeneously blended into a selected waterborne PU dispersion at varied weight ratios from 1/0.1 to 1/10 (w/w). PU was used to adhere the Ag nanohybrid to the metal surface. The resultant dispersions were analyzed and found to contain AgNP 2-18 nm in diameter and characterized by using UV absorption and TEM micrograph. The subsequent coating of AgNP/NSP-PU dispersion generated a film of 1.5 ?m thickness on the metal plate surface, further characterized by an energy dispersive spectroscope (EDS) to show the homogeneous distribution of Ag, Si, and C elements on the metal plates. The surface antimicrobial efficacy was proven for the coating composition of AgNP/NSP to PU ranging from 1/1 to 1/5 by weight ratio but irrelevant to the thickness of the coated materials. The metal plate coated with the high Ag content at 1/1 (w/w) ratio was shown to have very low cytotoxicity toward the contacted mammal fibroblasts. Overall, the optimized tricomponent Ag/silicate/PU in water dispersion from 1/2 to 1/3 (w/w) could generate a stable film on a metal surface exhibiting both antimicrobial and biocompatible properties. The facile coating technique of the AgNP/NSP in waterborne PU is proven to be viable for fabricating infection- and cytotoxicity-free medical devices. PMID:25307230

  17. Development of technique for AR coating and nickel and copper metallization of solar cells. FPS Project: Product development

    NASA Astrophysics Data System (ADS)

    Taylor, W.

    1982-04-01

    Printed nickel overplated with copper and applied on top of a predeposited silicon nitride antireflective coating system for metallizing solar cells was analyzed. The ESL D and E paste formulations, and the new formulations F, G, H, and D-1 were evaluated. The nickel thick films were tested after firing for stability in the cleaning and plating solutions used in the Vanguard-Pacific brush plating process. It was found that the films are very sensitive to the leaning and alkaline copper solutions. Less sensitivity was displayed to the neutral copper solution. Microscopic and SEM observations show segregation of frit at the silicon nitride thick film interface with loose frit residues after lifting off plated grid lines.

  18. Deposition of nanostructured crystalline and corrosion resistant alumina film on bell metal at low temperature by rf magnetron sputtering

    NASA Astrophysics Data System (ADS)

    Kakati, H.; Pal, A. R.; Bailung, H.; Chutia, Joyanti

    2009-05-01

    Aluminium oxide films deposited by rf magnetron sputtering for protective coatings have been investigated. The alumina films are found to exhibit grainy surface microstructure. The grain size, structure and density depend on different system parameters such as argon and/or oxygen flow rate and applied rf power etc. The effect of transition of the discharge from metallic to reactive mode on the surface characteristics of the alumina film is studied. X-ray diffractometry reveals that in poisoned mode of sputtering and under optimized power and pressure, crystalline alumina film can be grown. Different system conditions are optimized for corrosion resistant aluminium oxide films with good adhesion properties. Nanostructured alumina film is obtained at lower pressure (8 × 10 -4 to 9 × 10 -4 Torr) by rf reactive magnetron sputtering.

  19. Electromechanically driven chaotic dynamics of voids in metallic thin films

    Microsoft Academic Search

    Vivek Tomar; M. Rauf Gungor; Dimitrios Maroudas

    2010-01-01

    We report a systematic investigation of complex asymptotic states reached in the electromigration-driven morphological evolution of void surfaces in thin films of face-centered cubic metals with - and -oriented film planes under the simultaneous action of biaxial tension. The analysis is based on self-consistent dynamical simulations according to a realistic, well-validated, and fully nonlinear model. For -oriented film planes, we

  20. Vapor growth of electrochromic thin films of transition metal oxides

    NASA Astrophysics Data System (ADS)

    Gesheva, K. A.; Ivanova, T.; Marsen, B.; Zollo, G.; Kalitzova, M.

    2008-04-01

    Mixed oxide films of transition metals gain considerable much attention due to their interesting optoelectronic properties. The low temperature chemical vapor growth processing of thin films of mixed W and Mo oxides is presented. The investigation is related to optimization of films structure and the related optoelectronic properties in dependence on the chemical vapor deposition (CVD) process parameters. Their electrochromic behavior and photoelectrode properties were studied.

  1. Microstructural evolution of sputtered phase segregated metal composite thin films

    Microsoft Academic Search

    Dana I. Filoti

    2010-01-01

    In this thesis, we present the first comparative study of crystallographic texture development in three different types of metal thin film composites: fully miscible (Au-Ag), slightly immiscible (Cu-Ag) and immiscible (Au-SiO 2). Texture development refers to the distribution of orientations of crystallites in polycrystalline thin films, and is an important part of the microstructure that determines thin film properties. A

  2. Young's Moduli of Cold and Vacuum Plasma Sprayed Metallic Coatings

    NASA Technical Reports Server (NTRS)

    Raj, S. V.; Pawlik, R.; Loewenthal, W.

    2009-01-01

    Monolithic metallic copper alloy and NiCrAlY coatings were fabricated by either the cold spray (CS) or the vacuum plasma spray (VPS) deposition processes. Dynamic elastic modulus property measurements were conducted on these monolithic coating specimens between 300 K and 1273 K using the impulse excitation technique. The Young's moduli decreased almost linearly with increasing temperature at all temperatures except in the case of the CS Cu-23%Cr-5%Al and VPS NiCrAlY, where deviations from linearity were observed above a critical temperature. It was observed that the Young's moduli for VPS Cu-8%Cr were larger than literature data compiled for Cu. The addition of 1%Al to Cu- 8%Cr significantly increased its Young's modulus by 12 to 17% presumably due to a solid solution effect. Comparisons of the Young s moduli data between two different measurements on the same CS Cu- 23%Cr-5%Al specimen revealed that the values measured in the first run were about 10% higher than those in the second run. It is suggested that this observation is due to annealing of the initial cold work microstructure resulting form the cold spray deposition process.

  3. Negative index metamaterial combining magnetic resonators with metal films

    Microsoft Academic Search

    Uday K. Chettiar; Alexander V. Kildishev; Thomas A. Klar; Vladimir M. Shalaev

    2006-01-01

    We present simulation results of a design for negative index materials that\\u000auses magnetic resonators to provide negative permeability and metal film for\\u000anegative permittivity. We also discuss the possibility of using semicontinuous\\u000ametal films to achieve better manufacturability and enhanced impedance\\u000amatching.

  4. Combustion zone durability program-B. Task VIII. Sputter deposited ceramic and metallic coatings. Executive summary. [Graded metal; metal/ceramic layered; dense surface ceramic

    SciTech Connect

    Patten, J. W.; Moss, R. W.; Hays, D. D.

    1980-11-01

    The graded metal coatings are of the CoCrAlY type modified by including high Cr surface compositions, gradients in Cr and Al composition, underlayers and graded Pt additions, and Hf substitutions for Y. The metal ceramic layered coatings consist of alternate metal (Ni, Ni-Cr, CoCrAlY or Pt) and ceramic (Al/sub 2/O/sub 3/ or ZrO/sub 2/ + Y) layers. Investigations of dense surface ceramic coatings are directed towards methods for obtaining adherent impermeable ceramic protective coatings for gas turbine hot section components. Increased coating adherence is being sought through two coating designs intended to accomodate expansion and modulus mismatches at the coating-substrate interface.

  5. Improvement of Film Thickness Uniformity in TFA-MOD Coated Conductors

    NASA Astrophysics Data System (ADS)

    Katayama, K.; Nakahata, K.; Yoshizumi, M.; Izumi, T.; Shiohara, Y.

    TFA-MOD process is expected to be promising for future applications since it can produce high performance YBCO coated conductors with low cost. The dip-coating is adopted as the coating process because of its simplicity and controllability of the overall film thickness. Dip-coated films have uniform thickness along longitudinal direction, but not necessary in transverse direction. In the case of thicker films, the more cracks form during processing at the thicker region near the edges generate and propagate mainly due to tensile and bending strain. So we have to suppress the thickness distribution in transverse direction for thicker films for high IC values. In this study, we found that the thickness distribution was firstly given by meniscus shape and then the solution flew down till it's dried. The solution in the center region drops more since it is slowly dried compared with the edge region. Then, we developed a drying process, which accelerates the drying by blowing hot gas to prevent the coated solutions from dropping. As a result, the thickness uniformity was improved; the thickness ratio of the thick region (edge) to the flat one (center) was improved from 1.35 to 1.07. Furthermore, we successfully produced ~1.5 ?m thick films with high critical current density values (> 2MA/cm2) by the new coating process including the force drying step.

  6. Anomalous Hopping Exponents of Ultrathin Metal Films

    NASA Astrophysics Data System (ADS)

    Phillips, J. C.

    2001-03-01

    Under this title [1] has summarized data that show that a consistent underlying conduction mechanism is needed to explain thermally activated resistivities, logR(T) = logR + x(T*/T), with x = 0.75(5) on films of Ag, Bi, Pb, and Pd, with thicknesses 5-15A. Conventional continuum semiconductor models, with or without Coulomb interactions, give 1/4 < x < 1/2, and so do not explain x = 3/4, but a filamentary quantum percolation granular network relaxation model does. The concepts used in this unified, broad, non-crystalline platform have successfully derived scaling exponents and/or phase diagrams for network glasses (including window glass), polymers, electrolytes and alcohols, fused salts, molecular organic glasses, a-Si:H, quasicrystals, the impurity band metal-insulator transition (d = 2,3), high-temperature superconductors, and metabolic evolutionary biology [2,3]. [1] N. Markovic et al., Phys. Rev. B, 62, 2195 (2000). [2] J. C. Phillips, Phil. Mag. B, 80, 1773 (2000). [3] J. C. Phillips, Rep. Prog. Phys., 59, 1133 (1996).

  7. Effects of a ceramic coating on metal temperatures of an air-cooled turbine vane

    NASA Astrophysics Data System (ADS)

    Gladden, H. J.; Liebert, C. H.

    1980-02-01

    The metal temperatures of air cooled turbine vanes both uncoated and coated with the NASA thermal barrier system were studied experimentally. Current and advanced gas turbine engine conditions were simulated at reduced temperatures and pressures. Airfoil metal temperatures were significantly reduced, both locally and on the average, by use of the the coating. However, at low gas Reynolds number, the ceramic coating tripped a laminar boundary layer on the suction surface, and the resulting higher heat flux increased the metal temperatures. Simulated coating loss was also investigated and shown to increase local metal temperatures. However, the metal temperatures in the leading edge region remained below those of the uncoated vane tested at similar conditions. Metal temperatures in the trailing edge region exceeded those of the uncoated vane.

  8. Effects of a ceramic coating on metal temperatures of an air-cooled turbine vane

    NASA Technical Reports Server (NTRS)

    Gladden, H. J.; Liebert, C. H.

    1980-01-01

    The metal temperatures of air cooled turbine vanes both uncoated and coated with the NASA thermal barrier system were studied experimentally. Current and advanced gas turbine engine conditions were simulated at reduced temperatures and pressures. Airfoil metal temperatures were significantly reduced, both locally and on the average, by use of the the coating. However, at low gas Reynolds number, the ceramic coating tripped a laminar boundary layer on the suction surface, and the resulting higher heat flux increased the metal temperatures. Simulated coating loss was also investigated and shown to increase local metal temperatures. However, the metal temperatures in the leading edge region remained below those of the uncoated vane tested at similar conditions. Metal temperatures in the trailing edge region exceeded those of the uncoated vane.

  9. Organic hydrogen gas sensor with palladium-coated ?-phase poly(vinylidene fluoride) thin films

    NASA Astrophysics Data System (ADS)

    Imai, Yuji; Kimura, Yasuo; Niwano, Michio

    2012-10-01

    We have proposed an organic hydrogen gas sensor in which palladium (Pd)-coated ?-phase poly(vinylidene fluoride) (PVDF) films are utilized. Volume expansion of the Pd thin film caused by absorption of hydrogen gas is monitored by a piezoelectric thin film of PVDF attached to the Pd films. We have developed a simple method of synthesizing ?-phase PVDF films from ?-phase PVDF powder by using a wet process in which a mixture of acetone and hexamethylphosphoric triamide is used as the solvent for the PVDF powder. The sensor works by itself at room temperature without a power source.

  10. The performance of fluorescence gas sensor using TiO2 coated dye-porphyrin nanocomposite thin films

    Microsoft Academic Search

    Nurul Huda Yusoff; Muhamad Mat Salleh; Muhammad Yahaya

    2008-01-01

    This paper reports the performance of fluorescence gas sensor to detect the presence of volatile organic compounds. Two thin films were prepared; TiO2 coated with iron (III) meso-tetraphenylporphine chloride (TiO2 coated IMTPPCl) and TiO2 coated with manganase (III) 5,10,15,20 tetra (4-pyridyl)-21 H, 23 H porphine chloride tetrakis (TiO2 coated MnTPCl). All the thin films were deposited on quartz substrate using

  11. Silver activation on thin films of Ag-ZrCN coatings for antimicrobial activity.

    PubMed

    Ferreri, I; Calderon V, S; Escobar Galindo, R; Palacio, C; Henriques, M; Piedade, A P; Carvalho, S

    2015-10-01

    Nowadays, with the increase of elderly population and related health problems, knee and hip joint prosthesis are being widely used worldwide. However, failure of these invasive devices occurs in a high percentage thus demanding the revision of the chirurgical procedure. Within the reasons of failure, microbial infections, either hospital or subsequently-acquired, contribute in high number to the statistics. Staphylococcus epidermidis (S. epidermidis) has emerged as one of the major nosocomial pathogens associated with these infections. Silver has a historic performance in medicine due to its potent antimicrobial activity, with a broad-spectrum on the activity of different types of microorganisms. Consequently, the main goal of this work was to produce Ag-ZrCN coatings with antimicrobial activity, for the surface modification of hip prostheses. Thin films of ZrCN with several silver concentrations were deposited onto stainless steel 316L, by DC reactive magnetron sputtering, using two targets, Zr and Zr with silver pellets (Zr+Ag target), in an atmosphere containing Ar, C2H2 and N2. The antimicrobial activity of the modified surfaces was tested against S. epidermidis and the influence of an activation step of silver was assessed by testing samples after immersion in a 5% (w/v) NaClO solution for 5min. The activation procedure revealed to be essential for the antimicrobial activity, as observed by the presence of an inhibition halo on the surface with 11at.% of Ag. The morphology analysis of the surface before and after the activation procedure revealed differences in silver distribution indicating segregation/diffusion of the metallic element to the film's surface. Thus, the results indicate that the silver activation step is responsible for an antimicrobial effect of the coatings, due to silver oxidation and silver ion release. PMID:26117788

  12. Study of slurry spin coating technique parameters for the fabrication of anode-supported YSZ Films for SOFCs

    Microsoft Academic Search

    Jiaming Wang; Zhe Lü; Kongfa Chen; Xiqiang Huang; Na Ai; Jinyan Hu; Yaohui Zhang; Wenhui Su

    2007-01-01

    A slurry spin coating method was developed to fabricate gas-tight anode-supported YSZ films for solid oxide fuel cells (SOFCs). Several technique parameters for slurry spin coating, such as the slurry viscosity, spinning speed, number of coating cycles, film thickness and their effects on YSZ electrolyte film were investigated. SEM results, open-circuit voltage (OCV) values and cell performance indicated that these

  13. Antimicrobial edible films and coatings for fresh and minimally processed fruits and vegetables: a review.

    PubMed

    Valencia-Chamorro, Silvia A; Palou, Lluís; Del Río, Miguel A; Pérez-Gago, María B

    2011-01-01

    The use of edible films and coatings is an environmentally friendly technology that offers substantial advantages for shelf-life increase of many food products including fruits and vegetables. The development of new natural edible films and coatings with the addition of antimicrobial compounds to preserve fresh and minimally processed fruits and vegetables is a technological challenge for the industry and a very active research field worldwide. Antimicrobial agents have been successfully added to edible composite films and coatings based on polysaccharides or proteins such as starch, cellulose derivatives, chitosan, alginate, fruit puree, whey protein isolated, soy protein, egg albumen, wheat gluten, or sodium caseinate. This paper reviews the development of edible films and coatings with antimicrobial activity, typically through the incorporation of antimicrobial food additives as ingredients, the effect of these edible films on the control of target microorganisms, the influence of antimicrobial agents on mechanical and barrier properties of stand-alone edible films, and the effect of the application of antimicrobial edible coatings on the quality of fresh and fresh-cut fruits and vegetables. PMID:21888536

  14. A Quartz tuning fork-based humidity sensor using Nanocrystalline Zinc oxide thin film coatings

    Microsoft Academic Search

    Xiaofeng Zhou; Tao Jiang; Jian Zhang; Jianzhong Zhu; Xiaohua Wang; Ziqiang Zhu

    2006-01-01

    This paper describes an application of quartz tuning forks (QTF) coated with nanocrystalline ZnO films used as relative humidity sensors. The nanocrystalline ZnO thin films were deposited on the QTF by sol-gel method. The film was characterized by X-Ray Diffraction (XRD) and Atomic Force Microscope (AFM) to obtain the information on the structural and morphological properties. And the humidity sensitivity

  15. Functional properties of ZnO films prepared by thermal oxidation of metallic films

    NASA Astrophysics Data System (ADS)

    Rambu, A. P.; Tiron, V.; Nica, V.; Iftimie, N.

    2013-06-01

    We have prepared ZnO films by thermal oxidation of Zn metallic films and analyzed their structure, morphology, wettability, and gas sensing properties. Films structure and surface morphology were derived from X-ray diffraction and atomic force microscopy data. XRD analysis indicates that obtained ZnO films posses a crystalline structure. An increase of the surface roughness was observed, once the oxidation time increases. Surface wettability investigations showed that under UV-illumination, ZnO films present a reversible switching between hydrophobic and hydrophilic states. The gas response to methane, acetone, and formaldehyde was investigated, and experimental results indicate that tested films are selective to methane. Also, the gas response was found to increase, as the oxidation time of metallic films increases. This behavior was attributed to the structural changes (crystallite sizes, surface roughness), which take place during oxidation process.

  16. Electrolytic plasma processing for cleaning and metal-coating of steel surfaces

    Microsoft Academic Search

    E. I. Meletis; X. Nie; F. L. Wang; J. C. Jiang

    2002-01-01

    Electrolytic plasma processing (EPP) involves electrolysis and electrical discharge phenomena and it is an emerging, environmentally friendly surface engineering technology. Electrolytic-plasma\\/material surface interactions during processing can be used for cleaning of metal surfaces, formation of diffusion layers and\\/or deposition of metal, ceramic and composite coatings. The present work was concerned with cleaning and deposition of metal coatings on steel surfaces

  17. Brilliant and tunable color by changing pore diameter of metal-coated porous anodic alumina

    NASA Astrophysics Data System (ADS)

    Li, Jiawen; Zhu, Zhiqiang; Deng, Ping; Hu, Yanlei; Chu, Jiaru; Huang, Wenhao

    2012-11-01

    Porous anodic alumina (PAA), with highly ordered microstructures, has attracted much attention due to some unique physical and optical characteristics. In recent years, PAA is also used to obtain different colors by methods such as growing nanowires, tuning pore depth, or sputtering metal on PAA surface. In this paper, we report a simple and precisely controllable method to tune color by changing the pore diameter of PAA. In order to obtain PPA with different pore diameter, we first prepare the PPA membrane by two step anodization of high purity aluminium foil in acidic solutions and then immerse the fabricated PPA membrane into phosphoric acid to enlarge pore diameter. The different pore diameters of PAA are controlled by immersed time in phosphoric acid. After sputtering metal on surface of PAA, the brilliant color can be seen on the surface of PAA. Different colors of PAA film with metal-coated are obtained using this method and colorful patterns are successfully fabricated. The physical model of the PAA is constructed and the mechanism of tuning color is analyzed. It is concluded that the color can be tuned by changing pore diameter of the PAA membrane. This method will be of potential use in decoration, color displays and anti-counterfeiting technology.

  18. Effect of thermal cycling on stress in metallic films on ceramic substrates

    NASA Technical Reports Server (NTRS)

    Mattison, Edward M.; Vessot, Robert F. C.

    1990-01-01

    The hydrogen maser is the most stable frequency standard currently available for averaging intervals of hours to weeks. A major contributor to maser frequency variations is the maser's microwave resonant cavity: by means of the cavity pulling effect, a change in the cavity's resonance frequency produces a proportional change in the maser's output frequency. To minimize variations in the cavity's dimensions, and thus in its resonance frequency, maser cavities are often constructed of a low-expansivity glass-ceramic material coated on its surface with a conductive metallic film. It was previously shown that silver films like those used in SAO maser cavities develop tensile stress when cooled to room temperature after being fired onto the cavity, and that the stress in such films relaxes with time at a rate proportional to the level of stress. Stress relaxation in maser cavity coatings can alter the shape, and hence the resonance frequency, of the cavity, resulting in a slow variation in the maser's output frequency. The possibility was investigated of reversing the initial tensile stress by precooling the coated cavity material. It was hypothesized that cooling the material well below its normal working temperature and then warming it to its normal temperature would result in a lower tensile stress or even a compressive stress. Under such a condition stress relaxation, and thus any consequent frequency drifts, might be reduced or reversed.

  19. Study for Electrode Metals on Taste Sensor with LB film

    NASA Astrophysics Data System (ADS)

    Yokoya, Takahiro; Hirata, Takamichi; Akiya, Masahiro

    In this paper, sensor responses with only metal electrode as Au, Cr, Ti and more with LB film were described. LB film material was the Dioctadecyldimethylammonium bromide combined by PVSK as an underlayer. To detect five basic taste substances, sensor parameters were defined as maximum voltage change and response time. Response time for sourness and umami with Ti and Cr evaporated metal electrode was larger than that of usual Au electrode. LB film effect was finally found to increase response time for five basic taste materials.

  20. Characterization of electrically conductive transition metal dichalcogenide lubricant films

    Microsoft Academic Search

    Harish C. Waghray

    1997-01-01

    Groups VB and VIB transition metal dichalcogenides with layered structures, are intrinsic solid lubricants, and constitute a class of materials with unique and unusual properties based on their extreme anisotropy. The primary objective of this investigation was to conduct a comprehensive study on the tribological and electrical properties of burnished and sputtered transition metal dichalcogenide films, and characterize the performance

  1. Pulse handling capability of energy storage metallized film capacitors

    Microsoft Academic Search

    G. Picci; M. Rabuffi

    1999-01-01

    The aim of this work was to point out the current performance of metallized polypropylene film capacitors. Many tests have demonstrated that the contact between the sprayed terminations and the metallized electrodes is one of the most critical points for capacitors manufactured with this technology, generally when the capacitors are used in impulsive conditions. This is the case of energy

  2. Pulse handling capability of energy storage metallized film capacitors

    Microsoft Academic Search

    Guido Picci; Maurizio Rabuffi

    2000-01-01

    The aim of this work was to point out the current performance of metallized polypropylene film capacitors. Many tests have demonstrated that the contact between the sprayed terminations and the metallized electrodes is one of the most critical points for capacitors manufactured with this technology, generally when the capacitors are used in impulsive conditions. This is the case of energy

  3. Fabrication of electrically bistable organic semiconducting/ferroelectric blend films by temperature controlled spin coating.

    PubMed

    Hu, Jinghang; Zhang, Jianchi; Fu, Zongyuan; Weng, Junhui; Chen, Weibo; Ding, Shijin; Jiang, Yulong; Zhu, Guodong

    2015-03-25

    Organic semiconducting/ferroelectric blend films attracted much attention due to their electrical bistability and rectification properties and thereof the potential in resistive memory devices. During film deposition from the blend solution, spinodal decomposition induced phase separation, resulting in discrete semiconducting phase whose electrical property could be modulated by the continuous ferroelectric phase. However, blend films processed by common spin coating method showed extremely rough surfaces, even comparable to the film thickness, which caused large electrical leakage and thus compromised the resistive switching performance. To improve film roughness and thus increase the productivity of these resistive devices, we developed temperature controlled spin coating technique to carefully adjust the phase separation process. Here we reported our experimental results from the blend films of ferroelectric poly(vinylidene fluoride-trifluoroethylene (P(VDF-TrFE)) and semiconducting poly(3-hexylthiophene) (P3HT). We conducted a series of experiments at various deposition temperatures ranging from 20 to 90 °C. The resulting films were characterized by AFM, SEM, and VPFM to determine their structure and roughness. Film roughness first decreased and then increased with the increase of deposition temperature. Electrical performance was also characterized and obviously improved insulating property was obtained from the films deposited between 50 and 70 °C. By temperature control during film deposition, it is convenient to efficiently fabricate ferroelectric/semiconducting blend films with good electrical bistability. PMID:25748212

  4. Understanding Organic Film Behavior on Alloy and Metal Oxides

    PubMed Central

    Raman, Aparna; Quiñones, Rosalynn; Barriger, Lisa; Eastman, Rachel; Parsi, Arash

    2010-01-01

    Native oxide surfaces of stainless steel 316L and Nitinol alloys and their constituent metal oxides namely, nickel, chromium, molybdenum, manganese, iron and titanium were modified with long chain organic acids to better understand organic film formation. The adhesion and stability of films of octadecylphosphonic acid, octadecylhydroxamic acid, octadecylcarboxylic acid and octadecylsulfonic acid on these substrates was examined in this study. The films formed on these surfaces were analyzed by diffuse reflectance infrared Fourier transform spectroscopy, contact angle goniometry, atomic force microscopy and matrix assisted laser desorption ionization mass spectrometry. The effect of the acidity of the organic moiety and substrate composition on the film characteristics and stability is discussed. Interestingly, on the alloy surfaces, the presence of less reactive metal sites does not inhibit film formation. PMID:20039608

  5. Formation of molten metal films during metal-on-metal slip under extreme interfacial conditions

    NASA Astrophysics Data System (ADS)

    Liou, Nai-Shang; Okada, Makoto; Prakash, Vikas

    2004-09-01

    The present paper describes results of plate-impact pressure-shear friction experiments conducted to study time-resolved growth of molten metal films during dry metal-on-metal slip under extreme interfacial conditions. By employing tribo-pairs comprising hard tool-steel against relatively low melt-point metals such as 7075-T6 aluminum alloys, interfacial friction stress ranging from 100 to 400 MPa and slip speeds of approximately 100 m/ s have been generated. These relatively high levels of friction stress combined with high slip-speeds generate conditions conducive for interfacial temperatures to approach the melting point of the lower melt point metal (Al alloy) comprising the tribo-pair. A Lagrangian finite element code is developed to understand the evolution of the thermo-mechanical fields and their relationship to the observed slip response. The code accounts for dynamic effects, heat conduction, contact with friction, and full thermo-mechanical coupling. At temperatures below the melting point the material is described as an isotropic thermally softening elastic-viscoplastic solid. For material elements with temperatures in excess of the melt point a purely Newtonian fluid constitutive model is employed. The results of the hybrid experimental-computational study provides new insights into the thermoelastic-plastic interactions during high speed metal-on-metal slip under extreme interfacial conditions. During the early part of frictional slip the coefficient of kinetic friction is observed to decrease with increasing slip velocity. During the later part transition in interfacial slip occurs from dry metal-on-metal sliding to the formation of molten Al films at the tribo-pair interface. Under these conditions the interfacial resistance approaches the shear strength of the molten aluminum alloy under normal pressures of approximately 1- 3 GPa and shear strain rates of ˜10 7 s-1. The results of the study indicate that under these extreme conditions molten aluminum films maintain a shearing resistance as high as 100 MPa. Scanning electron microscopy of the slip surfaces reveal molten aluminum to be smeared on the tribo-pair interface. Knoop hardness measurements in 7075-T6 Al alloy at various depths from the slip interface indicate that the hardness increases approximately linearly with depth and reaches a plateau at approximately 40 ?m from the surface.

  6. Nano polymer Films by Fast Dip Coating Method for Field Effect Transistor Applications

    NASA Astrophysics Data System (ADS)

    Sathish, S.; Shekar, B. Chandar; Sathyamoorthy, R.

    Nano Polyvinyl alcohol films are prepared by fast dip coating method. Cleaned glass plates are used as substrate to prepare the above said films. The thickness of the films are measured by capacitance method, weighing method and cross checked by electronic measuring instrument (Tesatronic-TTD 20). IR spectrum is used to identify the coated films. The coated films are identified by IR spectrum. No pits and pin holes are found on the surface. The XRD spectrum indicated the amorphous nature of the films studied. Aluminium/PVA/Aluminum sandwich structures are formed to study the dielectric and AC conduction behaviour. The capacitance and dielectric loss of the films are measured in the frequency range of 0.1 kHz to 100 kHz for various temperatures ranging from 290 K to 450 K. The observed increase of capacitance with the decrease of frequency in the lower frequency range can be assigned to charge carriers being blocked at the electrodes. The decrease of capacitance with increasing frequency is also attributed to the increasing inability of the dipoles to orient them selves in a rapidly varying electric field. The AC conductivity is found to vary according to the relation ?ac ? ?n, where the value of n depends on temperature and frequency. The value of activation energy is found to be 0.0015 eV ?0.007 eV for various temperatures confirms the amorphous nature of the film.

  7. Molecular Interactions Between Alcohols and Metal Phthalocyanine Thin Films for Optical Gas Sensor Applications

    NASA Astrophysics Data System (ADS)

    Uttiya, Sureeporn; Kladsomboon, Sumana; Chamlek, Onanong; Suwannet, Wiriya; Osotchan, Tanakorn; Kerdcharoen, Teerakiat; Brinkmann, Martin; Pratontep, Sirapat

    Optically active organic gas sensors represent a promising molecular sensing device with low power consumption. We report experimental and computational investigations into the molecular interactions of metal phthalocyanine thin films with alcohol vapor. In the gas-sensing regime, the interactions of zinc phthalocyanine and alcohol molecules were studied by the Density Functional Theory (DFT) calculations, in comparison to the x-ray absorption spectroscopy. The DFT results reveal a reversible charge interaction mechanism between the zinc atom and the oxygen atom in the alcohol OH group, which corresponds to a shift in the x-ray absorption edge of the zinc atom. In the irreversible interaction regime, the effect of saturated alcohol vapor on spin-coated zinc phthalocyanine films was studied by the phase contrast microscopy, the optical absorption spectroscopy, and the transmission electron microscopy. Annealing the spin-coated films in saturated methanol vapor was found to induce an irreversible structural transformation from an amorphous to a crystalline phase, similar to the effect of a thermal annealing process. These crystallization processes of the zinc phthalocyanine films were also found to enhance their stability and alcohol sensing performance.

  8. Sorption and filtration of metals using iron-oxide-coated sand

    Microsoft Academic Search

    Mark M. Benjamin; Ronald S. Sletten; Robert P. Bailey; Thomas Bennett

    1996-01-01

    Iron oxides are good adsorbents for uncomplexed metals, some metal-ligand complexes, and many metal oxyanions. However, the adsorbent properties of these oxides are not fully exploited in wastewater treatment operations because of difficulties associated with their separation from the aqueous phase. This paper describes experiments in which iron oxides were coated onto the surface of ordinary filter sand, and this

  9. Molten metal containment vessel with rare earth oxysulfide protective coating thereon and method of making same

    DOEpatents

    Krikorian, Oscar H. (Danville, CA); Curtis, Paul G. (Tracy, CA)

    1992-01-01

    An improved molten metal containment vessel is disclosed in which wetting of the vessel's inner wall surfaces by molten metal is inhibited by coating at least the inner surfaces of the containment vessel with one or more rare earth oxysulfide or rare earth sulfide compounds to inhibit wetting and or adherence by the molten metal to the surfaces of the containment vessel.

  10. Materials Analysis of CED Nb Films Being Coated on Bulk Nb Single Cell SRF Cavities

    SciTech Connect

    Zhao, Xin; Reece, Charles; Palczewski, Ari; Ciovati, Gianluigi; Krishnan, Mahadevan; James, Colt; Irfan, Irfan

    2013-09-01

    This study is an on-going research on depositing a Nb film on the internal wall of bulk Nb single cell SRF cavities, via a cathodic arc Nb plasma ions source, an coaxial energetic condensation (CED) facility at AASC company. The motivation is to firstly create a homoepitaxy-like Nb/Nb film in a scale of a ~1.5GHz RF single cell cavity. Next, through SRF measurement and materials analysis, it might reveal the baseline properties of the CED-type homoepitaxy Nb films. Literally, a top-surface layer of Nb films which sustains SRF function, always grows up in homo-epitaxy mode, on top of a Nb nucleation layer. Homo-epitaxy growth of Nb must be the final stage (a crystal thickening process) of any coatings of Nb film on alternative cavity structure materials. Such knowledge of Nb-Nb homo-epitaxy is useful to create future realistic SRF cavity film coatings, such as hetero-epitaxy Nb/Cu Films, or template-layer-mitigated Nb films. One large-grain, and three fine grain bulk Nb cavities were coated. They went through cryogenic RF measurement. Preliminary results show that the Q0 of a Nb film could be as same as the pre-coated bulk Nb surface (which received a chemically-buffered polishing plus a light electro-polishing); but quality factor of two tested cavities dropped quickly. We are investigating if the severe Q-slope is caused by hydrogen incorporation before deposition, or is determined by some structural defects during Nb film growth.

  11. Thin film coating process using an inductively coupled plasma

    DOEpatents

    Kniseley, Richard N. (Ames, IA); Schmidt, Frederick A. (Ames, IA); Merkle, Brian D. (Ames, IA)

    1990-01-30

    Thin coatings of normally solid materials are applied to target substrates using an inductively coupled plasma. Particles of the coating material are vaporized by plasma heating, and pass through an orifice to a first vacuum zone in which the particles are accelerated to a velocity greater than Mach 1. The shock wave generated in the first vacuum zone is intercepted by the tip of a skimmer cone that provides a second orifice. The particles pass through the second orifice into a second zone maintained at a higher vacuum and impinge on the target to form the coating. Ultrapure coatings can be formed.

  12. Tensile and Adhesion Properties of Metal Thin Films Deposited onto Polyester Film Substrate Prepared by a Conventional Vacuum Evaporator

    NASA Astrophysics Data System (ADS)

    Kita, Takuya; Saitoh, Shou; Iwamori, Satoru

    Four kinds of metal, such as aluminum, copper, indium and tin, thin films were deposited onto polyester (PET) substrate by a conventional vacuum evaporator and evaluated their tensile and adhesion properties. The tensile property was estimated by observations of micro-cracks of the thin films due to the tensile test at 150°C. The tensile property of the metal thin films seems to relate with Brinell hardness and thickness of the thin film. The adhesion property of these metal thin films was estimated by measuring the pull strength. Aluminum thin film showed highest pull strength of all the thin films, and the pull strength increased with increase of the thickness.

  13. Antibacterial and physical properties of poly(vinyl chloride)-based film coated with ZnO nanoparticles.

    PubMed

    Li, X H; Xing, Y G; Li, W L; Jiang, Y H; Ding, Y L

    2010-06-01

    Nanoparticles of ZnO and their application in coating systems have attracted a great deal of attention in recent years because of its multifunction property, especially antibacterial activity. In this study, antibacterial and physical properties of poly(vinyl chloride) (PVC) based film coated with ZnO nanoparticles were investigated. It was found that the antibacterial action should be attributed to the killing effect property of ZnO nanoparticles. The ZnO-coated films treated by shaking for 10 h exhibited a similar high antibacterial activity against Escherichia coli and Staphylococcus aureus as the untreated ZnO-coated films. This result indicated that the ZnO nanoparticles adhered very well to the plastic film. The antibacterial activity of the ZnO-coated film to inactivate E. coli or S. aureus was improved by UV irradiation. The analysis of physical properties of the ZnO-coated films revealed that the nano-ZnO particles showed less effects on the tensile strength and elongation at break of the film. The ultraviolet (UV) light fastness of the ZnO-coated PVC film was improved, which may be attributed to the absorption of ZnO nanoparticles against UV light. Water vapor transmission of the ZnO-coated film decreased from 128 to 85 g/m(2) · 24 h, whereas the thickness of film increased from 6.0 ?m with increasing the amount of nano-ZnO particles coated from 0 to 187.5 ?g/cm(2). This research revealed that the PVC film coated with nano-ZnO particles has a good potential to be used as an active coating system for food packaging. PMID:21339138

  14. Reversible potentiometric oxygen sensors based on polymeric and metallic film electrodes.

    PubMed

    Yim, H S; Meyerhoff, M E

    1992-09-01

    Various materials and sensor configurations that exhibit reversible potentiometric responses to the partial pressure of oxygen at room temperature in neutral pH solution are examined. In one arrangement, platinum electrodes are coated with plasticized poly(vinyl chloride) films doped with a cobalt(II) tetraethylene pentamine complex. For such sensors, potentiometric oxygen response is attributed to a mixed potential originating from the underlying platinum electrode surface as well as a change in redox potential of the Co(II)-tetren-doped film as the complex binds oxygen reversibly. The response due to the platinum surface is prolonged by the presence of the Co(II)-tetren/PVC film. Alternately, thin films of metallic copper, electrochemically deposited on platinum and/or sputtered or vapor deposited on a single crystal silicon substrate, may be used for reversible oxygen sensing. The long-term reversibility and potentiometric stability of such copper film-based sensors is enhanced (up to 1 month) by preventing the formation of cuprous oxide on the surfaces via the application of an external nonpolarizing cathodic current through the working electrode or by specifically using sputtered copper films that have [100] preferred crystal structures as determined by X-ray diffraction. The implications of these findings in relation to fabricating analytically useful potentiometric oxygen sensors are discussed. PMID:1416035

  15. Magneto-optical features and extraordinary light transmission through perforated metal films filled with liquid crystals

    E-print Network

    Strelniker, Yakov M.

    Magneto-optical features and extraordinary light transmission through perforated metal films filled a metal film perforated by a periodic array of subwavelength holes has stimulated worldwide interest to perforated metal film made from metals traditionally used in such cases, such as Ag, Au, or Al , whose holes

  16. Growth of CdS thin films on indium coated glass substrates via chemical bath deposition and subsequent air annealing

    NASA Astrophysics Data System (ADS)

    Ghosh, Biswajit; Kumar, Kamlesh; Singh, Balwant Kr; Banerjee, Pushan; Das, Subrata

    2014-11-01

    In the present work attempts were made to synthesize indium doped CdS films by fabricating In/CdS bilayers using CBD-CdS on vacuum evaporated In thin films and subsequent air annealing. 135 nm CdS films were grown onto 20 nm and 35 nm indium coated glass substrate employing chemical bath deposition technique. The In/CdS bilayers thus formed were subjected to heat treatment at the temperatures between 200 and 400 °C for 4 min in the muffle furnace to facilitate indium to diffuse into the CdS films. XRD pattern ascertained no noticeable shift in lattice constant implying grain boundary metal segregation, while secondary ion mass spectrometry indicated the diffusion profile of indium into CdS matrices. Mass spectrometry results showed that substantial diffusion of indium had been taken place within CdS at 400 °C. Dark and photocurrent with different illumination time were measured to ascertain the photosensitivity of pure and composite CdS films.

  17. Pinhole defect evaluation of TiN films prepared by dry coating process

    Microsoft Academic Search

    H Uchida; M Yamashita

    2000-01-01

    Pinhole defects of TiN films deposited onto stainless steel by a few dry coating processes were evaluated potentiodynamically in a deaerated 0.5kmol\\/m3 H2SO4+0.05kmol\\/m3 KSCN solution at 298K. The critical passivation current density icrit in the TiN films prepared by activated reactive evaporation method decreased considerably with increasing film thickness. For the ?1.5?m thick films prepared by r.f. reactive sputtering, and

  18. Zinc oxide films prepared by sol–gel spin coating technique

    Microsoft Academic Search

    Sharul Ashikin Kamaruddin; Kah-Yoong Chan; Ho-Kwang Yow; Mohd Zainizan Sahdan; Hashim Saim; Dietmar Knipp

    2011-01-01

    Zinc oxide (ZnO) thin films and micro- and nanostructures are very promising candidates for novel applications in emerging\\u000a thin-film transistors, solar cells, sensors and optoelectronic devices. In this paper, a low-cost sol–gel spin coating technique\\u000a was used to fabricate ZnO films on glass substrates. The sol–gel fabrication process of the ZnO films is described. The influence\\u000a of precursor concentration on

  19. Indium tin oxide films prepared by atmospheric plasma annealing and their semiconductor-metal conductivity transition around room temperature

    NASA Astrophysics Data System (ADS)

    Li, Yali; Li, Chunyang; He, Deyan; Li, Junshuai

    2009-05-01

    We report the synthesis of indium tin oxide (ITO) films using the atmospheric plasma annealing (APA) technique combined with the spin-coating method. The ITO film with a low resistivity of ~4.6 × 10-4 ? cm and a high visible light transmittance, above 85%, was achieved. Hall measurement indicates that compared with the optimized ITO films deposited by magnetron sputtering, the above-mentioned ITO film has a higher carrier concentration of ~1.21 × 1021 cm-3 and a lower mobility of ~11.4 cm2 V-1 s-1. More interestingly, these electrical characteristics result in the semiconductor-metal conductivity transition around room temperature for the ITO films prepared by APA.

  20. Plasmonic waveguide modes of film-coupled metallic nanocubes.

    PubMed

    Lassiter, J Britt; McGuire, Felicia; Mock, Jack J; Ciracì, Cristian; Hill, Ryan T; Wiley, Benjamin J; Chilkoti, Ashutosh; Smith, David R

    2013-01-01

    A metallic nanoparticle positioned over a metal film offers great advantages as a highly controllable system relevant for probing field-enhancement and other plasmonic effects. Because the size and shape of the gap between the nanoparticle and film can be controlled to subnanometer precision using relatively simple, bottom-up fabrication approaches, the film-coupled nanoparticle geometry has recently been applied to enhancing optical fields, accessing the quantum regime of plasmonics, and the design of surfaces with controlled reflectance. In the present work, we examine the plasmon modes associated with a silver nanocube positioned above a silver or gold film, separated by an organic, dielectric spacer layer. The film-coupled nanocube is of particular interest due to the formation of waveguide cavity-like modes between the nanocube and film. These modes impart distinctive scattering characteristics to the system that can be used in the creation of controlled reflectance surfaces and other applications. We perform both experimental spectroscopy and numerical simulations of individual nanocubes positioned over a metal film, finding excellent agreement between experiment and simulation. The waveguide mode description serves as a starting point to explain the optical properties observed. PMID:24199752

  1. Calcium and Zinc Containing Bactericidal Glass Coatings for Biomedical Metallic Substrates

    PubMed Central

    Esteban-Tejeda, Leticia; Díaz, Luis A.; Prado, Catuxa; Cabal, Belén; Torrecillas, Ramón; Moya, José S.

    2014-01-01

    The present work presents new bactericidal coatings, based on two families of non-toxic, antimicrobial glasses belonging to B2O3–SiO2–Na2O–ZnO and SiO2–Na2O–Al2O3–CaO–B2O3 systems. Free of cracking, single layer direct coatings on different biomedical metallic substrates (titanium alloy, Nb, Ta, and stainless steel) have been developed. Thermal expansion mismatch was adjusted by changing glass composition of the glass type, as well as the firing atmosphere (air or Ar) according to the biomedical metallic substrates. Formation of bubbles in some of the glassy coatings has been rationalized considering the reactions that take place at the different metal/coating interfaces. All the obtained coatings were proven to be strongly antibacterial versus Escherichia coli (>4 log). PMID:25056542

  2. Fabrication of Metal Oxide Thin Films Using the Langmuir-Blodgett Deposition Technique.

    NASA Astrophysics Data System (ADS)

    Johnson, David John

    The Langmuir Blodgett (LB) deposition of metal arachidates was investigated as a technique for fabrication of metal oxides with emphasis placed on the lanthanide arachidates. Traditionally, these materials are difficult to deposit via the LB process, due to the rigidity of the floating monolayer. Studies on yttrium arachidate have shown that the quality of deposition of these materials is highly dependent on the concentration of the metal salt and the pH of the subphase. Yttrium arachidate was thus deposited at 10^{-5} M YCl_3 over a pH range of 4.0 to 6.9. Uniform multilayer films were produced with films at the higher pH's showing 100% yttrium arachidate. A pK_{rm a} value of 4.9 +/- 0.2 was obtained under these conditions. Fourier transform infrared spectroscopy, Rutherford backscattering spectrometry and x-ray photoelectron spectroscopy data indicate that the metal is being incorporated into the arachidic acid predominantly as Y(OH) ^{2+}. A saturation areal density of (2.0 +/- 0.1) times 10^{14} Y/cm ^2 was measured for one layer of yttrium arachidate. Ellipsometric measurements were performed on films of yttrium arachidate to study order-disorder transitions. Upon heating the films were observed to undergo two transitions at 65^circC and 100 ^circC. At room temperature, the as -deposited films were found to be anisotropic with indices of refraction of N_{rm x} = 1.503 +/- 0.005 and N _{rm z} = 1.554 +/- 0.005 and a monolayer spacing of 2.73 +/- 0.03 nm. Above 100^ circC the films were isotropic with N = 1.440 +/- 0.005 and a thickness of 3.13 +/- 0.03 nm per original layer. The films showed no desorption below 100^circ C. In contrast to films of cadium arachidate, the yttrium arachidate films were observed to undergo supercooling by 35^circC. This may point to a lack of nucleation sites in the yttrium arachidate films explaining why they maintain areal integrity at high temperature while cadmium arachidate films do not. The decomposition of LB films was studied in some detail, using two processes: thermal decomposition and decomposition via ultraviolet/ozone exposure. The second technique was found to reduce LB arachidate multilayers to a metal carbonate (at a rate of less than 1 minute per layer), which could be further decomposed into an oxide via a thermal treatment. The ultraviolet/ozone process allowed uniform films of CdO to be produced in addition to the thin films of Y_2O_3 , Er_2O_3 and La_2O_3 fabricated via either thermal or ultraviolet/ozone processing. Applications of the LB produced metal oxides were investigated. Electrical characterization of Y _2O_3 dielectric layers gave a permittivity of varepsilon~ 11.5 +/- 0.9 and good quality metal -oxide-semiconductor structures of <10 nm in thickness. Y_2O_3 coatings on 304 stainless steel were found to significantly reduce thermal oxidation of the steel at 800^ circC. Finally, La_2O _3 interface layers in PZT/Pt structures were found to have a significant effect on the nucleation and growth of the ferroelectric.

  3. CO 2 laser cutting of metallic coated sheet steels

    Microsoft Academic Search

    J Wang; W. C. K Wong

    1999-01-01

    Sheet steels with zinc and aluminum coatings, such as Galvabond, exhibit an anomalous behavior when subjected to laser light and pose some severe machining limitations by virtue of the high light reflectivity and thermal conductivity of the coatings as well as the difference in physical properties between the coating and substrate materials. An investigation of the machinability of Galvabond using

  4. Characterization of thermally aged AlPO4-coated LiCoO2 thin films

    PubMed Central

    2012-01-01

    The electrochemical properties and stability during storage of pristine and AlPO4-coated LiCoO2 thin films were characterized. The wide and smooth surface of the thin film electrode might provide an opportunity for one to observe surface reactions with an electrolyte. The rate capability and cyclic performance of the LiCoO2 thin film were enhanced by AlPO4 surface coating. Based on secondary ion mass spectrometry analysis and scanning electron microscopy images of the surface, it was confirmed that the coating layer was successfully protected from the reactive electrolyte during storage at 90°C. In contrast, the surface of the pristine sample was severely damaged after storage. PMID:22221315

  5. Thin film thermoelectric devices as thermal control coatings: A study

    NASA Technical Reports Server (NTRS)

    Clemons, J. M.; Krupnick, A. C.

    1973-01-01

    Peltier effect, Thomson effect, and Seeback effect are utilized in design of thermal control coating that serves as versatile means for controlling heat absorbed and radiated by surface. Coatings may be useful in extreme temperature environment enclosures or as heat shields.

  6. Microstructure and Electrochemical Behavior of Fe-Based Amorphous Metallic Coatings Fabricated by Atmospheric Plasma Spraying

    Microsoft Academic Search

    Z. Zhou; L. Wang; D. Y. He; F. C. Wang; Y. B. Liu

    2011-01-01

    A Fe48Cr15Mo14C15B6Y2 alloy with high glass forming ability (GFA) was selected to prepare amorphous metallic coatings by atmospheric plasma spraying (APS). The as-deposited coatings present a dense layered structure and low porosity. Microstructural studies show that some nanocrystals and a fraction of yttrium oxides formed during spraying, which induced the amorphous fraction of the coatings decreasing to 69% compared with

  7. Thermally Sprayed Coatings as Effective Tool Surfaces in Sheet Metal Forming Applications

    Microsoft Academic Search

    V. Franzen; J. Witulski; A. Brosius; M. Trompeter; A. E. Tekkaya

    2011-01-01

    Two approaches to produce wear-resistant effective surfaces for deep drawing tools by thermal arc wire spraying of hard materials\\u000a are presented. Arc wire spraying is a very economic coating technique due to a high deposition rate. The coated surface is\\u000a very rough compared to that of conventional sheet metal forming tools. In the first approach, the coated surface is smoothed

  8. Surface-modification of LiMn 2O 4 with a silver-metal coating

    Microsoft Academic Search

    J. T. Son; K. S. Park; H. G. Kim; H. T. Chung

    2004-01-01

    Spenel lithium manganese oxides with a nominal composition of LiMn2O4 are prepared by using a conventional ceramic synthesis method and are coated by a chemical deposition of silver particles. The silver-coated nano-particle LiMn2O4 shows excellent cycleability at 2C galvanostatic conditions. The high surface electronic conductivity caused by the metal coating reduces cell polarization. The results indicate that such surface treatment

  9. Electromagnetic levitation: A new technology for high rate physical vapour deposition of coatings onto metallic strip

    Microsoft Academic Search

    Laurent Baptiste; Nitte van Landschoot; Gerard Gleijm; Janis Priede; Jan Schade van Westrum; Han Velthuis; Tae-Yeob Kim

    2007-01-01

    For about three decennia, there has been a growing interest from the strip coating business in fully continuous or semi-continuous PVD based coating processes.For the deposition of thin coatings (?<100 nm) on polymer webs and thin metal foils, magnetron sputtering has become the predominant technology. However, the deposition rate obtained with magnetron sputtering is too low to be economically interesting for

  10. Effect of the manufacturing conditions on the structure and permeability of polymer films intended for coating undergoing phase separation.

    PubMed

    Marucci, Mariagrazia; Arnehed, Johan; Jarke, Annica; Matic, Hanna; Nicholas, Mark; Boissier, Catherine; von Corswant, Christian

    2013-02-01

    The major aim of this work was to study the effect of two process parameters, temperature and coating flow, on permeability to water and structure of free films sprayed from mixtures of ethyl cellulose (EC), hydroxypropyl cellulose (HPC), and ethanol. The films were sprayed in a new spraying setup that was developed to mimic the film coating process in a fluid bed and to provide well controlled conditions. EC and HPC phase separated during the film drying process, and EC- and HPC-rich domains were formed. The process parameters had a great impact on the structure and the permeability to water of the films. The longer the time before the film structure was locked by a high film viscosity, that is, the lower the temperature and the higher the coating flow, the larger the domains and the lower the film permeability. The effective diffusion coefficient of water in the films varied by about six times within the range of the process parameters studied. Structures of sprayed films and water effective diffusion coefficients in sprayed films were compared to those of cast films. For the cast films, the domains were bigger, and the permeability to water was significantly lower compared to those of the sprayed films. The results indicate that the process parameters can be used as a mean to regulate structure and permeability of coating films undergoing phase separation. PMID:23064326

  11. Solar absorptance of copper-cobalt oxide thin film coatings with nano-size, grain-like morphology: Optimization and synchrotron radiation XPS studies

    NASA Astrophysics Data System (ADS)

    Amri, Amun; Duan, XiaoFei; Yin, Chun-Yang; Jiang, Zhong-Tao; Rahman, M. Mahbubur; Pryor, Trevor

    2013-06-01

    Copper-cobalt oxides thin films had been successfully coated on reflective aluminium substrates via a facile sol-gel dip-coating method for solar absorptance study. The optimum absorptance in the range of solar radiation is needed for further optimum design of this material for selective solar absorber application. Field emission scanning electron microscopy was used to characterize the surface morphology of the coating whereby nano-size, grain-like morphology was observed. Synchrotron radiation X-ray photoelectron spectroscopy was employed to analyze the electronic structure of the coated surface showing that the (i) oxygen consisted of lattice, surface and subsurface oxygen, (ii) copper consisted of octahedral and tetrahedral Cu+, as well as octahedral and paramagnetic Cu2+ oxidation states, and (iii) cobalt consisted of tetrahedral and paramagnetic Co(II), octahedral Co(III) as well as mixed Co(II,III) oxidation states. In order to optimize the solar absorptance of the coatings, relevant parameters such as concentrations of cobalt and copper, copper/cobalt concentration ratios and dip-speed were investigated. The optimal coating with ? = 83.4% was produced using 0.25 M copper acetate and 0.25 M cobalt chloride (Cu/Co ratio = 1) with dip-speed 120 mm/min (four cycles). The operational simplicity of the dip-coating system indicated that it could be extended for coating of other mixed metal oxides as well.

  12. Electrochemical characterization of YSZ thick films deposited by dip-coating process

    Microsoft Academic Search

    F. Mauvy; P. Lenormand; C. Lalanne; F. Ansart; J. M. Bassat; J. C. Grenier

    2007-01-01

    Yttria stabilized zirconia (YSZ, 8% Y2O3) thick films were coated on dense alumina substrates by a dip-coating process. The suspension was obtained by addition of a polymeric matrix in a stable suspension of commercial YSZ (Tosoh) powders dispersed in an azeotropic mixture MEK–EtOH. The suspension composition was improved by the addition of YSZ Tosoh particles encapsulated by zirconium alkoxide sol

  13. Super-hydrophobic surfaces of layer-by-layer structured film-coated electrospun nanofibrous membranes

    Microsoft Academic Search

    Tasuku Ogawa; Bin Ding; Yuji Sone; Seimei Shiratori

    2007-01-01

    We have recently fabricated super-hydrophobic membrane surfaces based on the inspiration of self-cleaning silver ragwort leaves. This biomimetic super-hydrophobic surface was composed of fluoroalkylsilane (FAS)-modified layer-by-layer (LBL) structured film-coated electrospun nanofibrous membranes. The rough fibre surface caused by the electrostatic LBL coating of TiO2 nanoparticles and poly(acrylic acid) (PAA) was used to imitate the rough surface of nanosized grooves along

  14. Characteristics of Nanohybrid Coating Films Synthesized from Colloidal Silica and Organoalkoxysilanes by Sol-Gel Process

    Microsoft Academic Search

    Moonkyong Na; Dongpil Kang; Myeongsang Ahn; Heewoong Lee

    2008-01-01

    Organic-inorganic hybrid sols were synthesized using colloidal silica and organoalkoxysilane using the sol-gel process. Hybrid sols were functionalized using methyltrimethoxysilane (MTMS) and gamma-glycidoxypropyltrimethoxysilane (GTMS). Coating films were formed on a glass substrate using a spin coating procedure. The hybrid sols were evaluated for stability and thermal degradation. Viscosity increased markedly when the hybrid sols were reacted for 10 d. It

  15. Nafion-coated mercury thin film electrodes for batch-injection analysis with anodic stripping voltammetry

    Microsoft Academic Search

    Christopher M. A. Brett; Ana Maria Oliveira Brett; Frank-Michael Matysik; Silke Matysik; Sunita Kumbhat

    1996-01-01

    Batch-injection analysis exhibits the advantages of rapid and simple electroanalysis of microlitre samples. Nafion-coated mercury thin film electrodes have been evaluated for use in batch-injection analysis with anodic stripping voltammetry (BIA-ASV). The advantages of Nafion-coated electrodes in reducing electrode contamination by components of complex matrices are combined with the analysis of small microlitre sample volumes. The measurement of traces of

  16. Mechanical Properties and Microstructure of Plasma Sprayed Ni-Based Metallic Glass Coating

    NASA Astrophysics Data System (ADS)

    Kobayashi, Akira; Kuroda, Toshio; Kimura, Hisamichi; Inoue, Akihisa

    2010-10-01

    Various developmental research works on the metallic glass have been conducted in order to broaden its application field. Thermal spraying method is one of the potential techniques to enhance the excellent properties such as high toughness and corrosion resistance of the metallic glass material. The gas tunnel type plasma spraying is useful to obtain high quality ceramic coatings such as Al2O3 and ZrO2 coatings. In this study, the Ni-based metallic glass coatings were produced by the gas tunnel type plasma spraying under various experimental conditions, and their microstructure and mechanical properties were investigated. At the plasma current of 200-300 A, the Ni-based metallic glass coatings of more than 200 ?m in thickness were formed densely with Vickers hardness of about Hv = 600.

  17. Optimized upper bound analysis of polymer coated metal rod extrusion through conical die

    E-print Network

    Shah, Ritesh Lalit

    2007-09-17

    after the extrusion process. In the present research study a new upper bound analytical model is developed to predict the forces required to conduct extrusion of a polymer coated metal rod successfully. The search for the lower upper bound power...

  18. Fabrication and Evaluation of One-Axis Oriented Lead Zirconate Titanate Films Using Metal-Oxide Nanosheet Interface Layer

    NASA Astrophysics Data System (ADS)

    Minemura, Yoshiki; Nagasaka, Kohei; Kiguchi, Takanori; Konno, Toyohiko J.; Funakubo, Hiroshi; Uchida, Hiroshi

    2013-09-01

    Nanosheet Ca2Nb3O20 (ns-CN) layers with pseudo-perovskite-type crystal configuration were applied on the surface of polycrystalline metal substrates to achieve preferential crystal orientation of Pb(Zr,Ti)O3 (PZT) films for the purpose of enhanced ferroelectricity comparable to that of epitaxial thin films. PZT films with tetragonal symmetry (Zr/Ti=0.40:0.60) were fabricated by chemical solution deposition (CSD) on ns-CN-buffered Inconel 625 and SUS 316L substrates, while ns-CN was applied on the the substrates by dip-coating. The preferential crystal growth on the ns-CN layer can be achieved by favorable lattice matching between (001)/(100)PZT and (001)ns-CN planes. The degree of (001) orientation was increased for PZT films on ns-CN/Inconel 625 and ns-CN/SUS 316L substrates, whereas randomly-oriented PZT films with a lower degree of (001) orientation were grown on bare and Inconel 625 films. Enhanced remanent polarization of 60 µC/cm2 was confirmed for the PZT films on ns-CN/metal substrates, ascribed to the preferential alignment of the polar [001] axis normal to the substrate surface, although it also suffered from higher coercive field above 500 kV/cm caused by PZT/metal interfacial reaction.

  19. Coating composition for inhibiting corrosion of metal substrates

    SciTech Connect

    Seibel, L.P.

    1993-06-29

    The corrosion-inhibiting coating composition for application to a metal substrate is described comprising: (a) from about 55% to about 78.5%, by weight of nonvolatile material, of an epoxy resin having a molecular weight of about 15,000 to about 80,000; (b) from about 20% to about 40%, by weight of nonvolatile material, of a phenolic resin; (c) from about 1.5% to about 5%, by weight of nonvolatile material, of an organic corrosion inhibitor having the structural formula: wherein each R is selected, independently, from the group consisting of hydrogen, alkyl, haloalkyl, alkoxy, alkylthio, alkylsulfonyl, cycloalkyl, phenyl, alkylphenyl, phenylalkyl, halo, cyano, nitro, carboxyl, carboxyalkyl, hydroxy, amino, and carbamoyl, and wherein R[sub 1], R[sub 2], R[sub 3] and R[sub 4] are selected, independently, from the group consisting of hydrogen, alkyl, hydroxyalkyl, haloalkyl, alkoxyalkyl, carboxyalkyl, carboxyl, phenyl, and phenylalkyl, and wherein at least one of the R[sub 1], R[sub 2], R[sub 3] and R[sub 4] groups is a carboxyl group; and (d) a sufficient amount of a nonaqueous carrier such that the corrosion-inhibiting composition includes from about 20% to about 40%, by weight of the total composition, of nonvolatile material.

  20. Radioisotope albedo thickness gauging of polymer coatings on a metallic substrate

    SciTech Connect

    Kapranov, B.I.; Myakin 'Kova, L.V.; Shaverin, V.A.

    1986-12-01

    This paper presents results of theoretical and experimental analysis of the possibilities of albedo thickness gauging of the polymer coating on metals. The ranges of measured coating thickness and their relationship with the thickness of the substrate for aluminum, copper, steel, and lead using Pm 147, Am 241, Cd 109, and Co 57 radionuclides as readiation sources are presented.

  1. Hybrid organic-inorganic network coatings for protecting metal substrates from abrasion and corrosion

    SciTech Connect

    Jordens, K.; Wilkes, G. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States)

    1996-12-31

    Ceramers or Ormocers are hybrid organic-inorganic materials first created a decade ago, and are the subject of a recent review article. Recent research from the authors laboratory in this area of materials science has focused on synthesizing protective coatings for (soft) polymeric substrates, i.e. polycarbonate. The authors have now extended the application of such coatings to metallic substrates.

  2. Residual stress and thermo-mechanical properties of cold spray metal coatings

    Microsoft Academic Search

    V. Luzin; K. Spencer; M.-X. Zhang

    2011-01-01

    The residual stress profiles in Cu and Al coatings cold sprayed using kinetic metallization have been studied using neutron diffraction. To interpret results and to describe them quantitatively, the measured profiles were fit to Tsui and Clyne’s progressive coating deposition model, which demonstrated that the residual stresses are largely due to kinetic and not thermal effects. The residual stress state

  3. Biomedical effect of tissue contact with metallic material used for body piercing modified by DLC coatings

    Microsoft Academic Search

    D. Bociaga; K. Mitura

    2008-01-01

    Body piercing is one of the most popular methods to decorate the body at present. All the time this metallic material is in contact with body fluids and living tissues. It is well documented that carbon coatings were examined and pointed as safe and biocompatible. In this connection the jewellery made of 316L steel was covered by diamond-like coatings using

  4. High Performance Optical Coatings Utilizing Tailored Refractive Index Nanoporous Thin Films

    NASA Astrophysics Data System (ADS)

    Poxson, David J.

    Refractive index is perhaps the most important quantity in optics. It is particularly relevant in the field of optical coatings, where the refractive index appears in virtually every optics equation as a figure of merit. Recently it has been demonstrated through control of the deposition angle during oblique-angle electron-beam deposition, nanoporous films of virtually any desired porosity may be accurately deposited. As the porosity of a nanoporous film directly relates to its effective refractive index, the refractive index value of a film may be tailored to any value between that of the bulk material and close to that of air. These two characteristics, namely; (i) tailored-refractive index and (ii) very low-refractive index values close to that of air, offer significant advantages in the design and optical performance in all optical coating applications. In this dissertation we explore optical coating applications whose performance can be greatly enhanced by utilization of a tailored- and low-refractive index nanoporous material system. One such important application is in the design and fabrication of broadband, omnidirectional antireflection (AR) coatings on solar cell devices. To harness the full spectrum of solar energy, Fresnel reflections at the surface of a photovoltaic cell must be reduced as much as possible over the relevant solar wavelength range and over a wide range of incident angles. However, the development of AR coatings embodying omni-directionality over a wide range of wavelengths is challenging. By utilizing the tailored- and low-refractive index properties of the nanoporous material system, in conjunction with a computational genetic algorithm and a predictive quantitative model for the porosity of such nanoporous films, truly optimized AR coatings can be designed and fabricated on solar cells. Here we show that these optimized AR structures demonstrate significant improvement to overall device efficiency. Traditionally, nanoporous films fabricated by oblique-angle deposition techniques have been restricted to rigid and planar substrates such as silicon and glass. This limitation greatly constrains the applicability, tailorability, functionality and even the economic viability of such nanoporous films. As another avenue into extending the applicability of such films, here we demonstrate a novel nanoporous film / polymer substrate composite system fabricated by utilizing oblique-angle electron-beam methodology. This unique composite system exhibits several favorable characteristics, namely i) fine-tuned control over film nano-porosity and thickness, ii) excellent adhesion between the nanoporous film and polymer substrate, iii) and ability to withstand significant and repeated bending as well as three dimensional molding, all the while closely retaining the composite system's designed nanostructure and optical properties. These newly available characteristics show promise to greatly extend the range of applications and functionalities of such nanoporous films.

  5. Metal-insulator transition in epitaxial vanadium sesquioxide thin films

    NASA Astrophysics Data System (ADS)

    Allimi, Bamidele S.

    Of all the transition metal oxides which exhibit metal-insulator transitions (MIT), one of the most extensively studied in recent years is the vanadium sesquioxide (V2O3), both from experimental and theoretical point of view. At a transition temperature of about 160 K at an ambient pressure of 1 atm, pure V2O3 transforms from a rhombohedral paramagnetic metallic (PM) to a monoclinic antiferromagnetic insulating (AFI) phase upon cooling, with a jump in the resistivity of about seven orders of magnitude. Experimental studies have focused more on bulk V2O3 and recently there have been significant interest in thin film fabrication of this material due to potential applications as thermal sensors, current limiters, Positive Temperature Coefficient (PTC) thermistors, and optical switches. This study addresses the deposition, characterization, and properties of high-quality epitaxial V2O3 thin films grown on a-, c-Al2O3 and c-LiTaO 3 substrates by a straightforward method of pulsed laser deposition (PLD). Various characterization techniques including X-ray diffraction, atomic force microscopy, scanning electron microscopy, and X-ray photoemission spectroscopy were used to examine the structural, crystallographic, and surface properties, while four point probe resistivity measurements were used to examine the electrical properties of the films. V2O3 thin films of different thicknesses ranging from 10-450 nm were deposited on c-Al 2O3 and c-LiTaO3 substrates by PLD to understand also the role of epitaxial strains. Resistivity measurements showed that depending on the thicknesses of films, different electrical transitions were exhibited by the samples. While some of the samples displayed the expected metal-insulator transition typical of bulk V2O3, some showed insulating behavior only and others exhibited metallic characteristics only over the whole temperature range. For example, for films on c-LiTaO3 with increasing film thickness, first an insulator-insulator, then a metal-insulator, followed by a metal-metal transition is observed. Thicker films (>202 nm) remain metallic in the temperature range of the measurements.

  6. Antimicrobial activity of allyl isothiocyanate used to coat biodegradable composite films as affected by storage and handling conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We evaluated the effects of storage and handling conditions on the antimicrobial activity of biodegradable composite films (polylactic acid and sugar beet pulp) coated with allyl isothiocyanate (AIT). Polylactic acid (PLA) and chitosan were incorporated with AIT and coated on one side of the film. T...

  7. Improved electrical conductivity of graphene films integrated with metal nanowires.

    PubMed

    Kholmanov, Iskandar N; Magnuson, Carl W; Aliev, Ali E; Li, Huifeng; Zhang, Bin; Suk, Ji Won; Zhang, Li Li; Peng, Eric; Mousavi, S Hossein; Khanikaev, Alexander B; Piner, Richard; Shvets, Gennady; Ruoff, Rodney S

    2012-11-14

    Polycrystalline graphene grown by chemical vapor deposition (CVD) on metals and transferred onto arbitrary substrates has line defects and disruptions such as wrinkles, ripples, and folding that adversely affect graphene transport properties through the scattering of the charge carriers. It is found that graphene assembled with metal nanowires (NWs) dramatically decreases the resistance of graphene films. Graphene/NW films with a sheet resistance comparable to that of the intrinsic resistance of graphene have been obtained and tested as a transparent electrode replacing indium tin oxide films in electrochromic (EC) devices. The successful integration of such graphene/NW films into EC devices demonstrates their potential for a wide range of optoelectronic device applications. PMID:23083055

  8. Mechanical and adhesive properties of cellulosic film coats containing polymeric additives.

    PubMed

    Pooponpun, S; Polnok, A; Paeratakul, O; Kraisit, P; Sarisuta, N

    2015-05-01

    The effects of some polymeric additives, i.e. corn starch (CS) and magnesium stearate (MS), on mechanical properties (tensile strength, modulus of elasticity, and elongation at break) and adhesive toughness of hydroxypropyl methylcellulose (HPMC) and ethylcellulose (EC) film coats were investigated. The free and in situ films containing 10 and 20% additives by weight of polymer were prepared by spray method. The mechanical properties of both HPMC and EC free films decreased as the concentration of additives was increased because of the lower stiffening effect brought about by hydrodynamic or reinforcing effect. However, adhesive toughness of in situ films was found to increase for HPMC whereas that of EC films decreased with the increasing concentration of polymeric additives. Such contradictory results between these two film forming polymers may be attributed to the net result of the opposite effects between interference of film-tablet interfacial bonds and the reduction of mechanical properties. The former seemed to be preferential in the case of EC films, while the latter predominated for HPMC films. Such conclusions were supported by the FTIR results, in which the polymer-additive interaction was found for EC. Increase in concentration of polymeric additives resulted in the decrease in mechanical properties of free films whereas the adhesive toughness of in situ films may be influenced by either the interference of film-tablet interfacial bonds or the significant reduction of mechanical properties. PMID:26062297

  9. Novel conductive characteristics of ITO:Ti films deposited by spin coating from colloidal precursor

    Microsoft Academic Search

    A. Al-Kahlout; S. Heusing; T. Mueller; N. Aldahoudi; M. Quilitz; P. W. de Oliveira

    Transparent semiconducting ITO:Ti thin films, prepared by a sol–gel process, has been deposited by spin-coating technique\\u000a onto alkali-free glass substrates. The as-coated films were annealed in ambient air at 550 °C for 1 h and further annealed\\u000a in a reducing atmosphere. The influences of the Ti content in the sol on the surface morphology, microstructure, optical properties\\u000a and electrical resistivity have been

  10. On Coating Durability of Polymer Coated Sheet Metal under Plastic Deformation 

    E-print Network

    Huang, Yu-Hsuan

    2011-08-08

    Page Table 1 Two types of Coated sheets ..................................................................... 34 Table 2 Initial Pull-off stress of coated-sheets ..................................................... 35 Table 3 Young?s modulus... the Venetian blinds manufacturers in the 1940s. Now, the coil coating process could reduce VOCs emissions and prevent the formation of hazardous wastes with its highly automated and continuous process [2, 3]. As shown in Figure 1, a typical coil coating line...

  11. Thermal contact conductance of metallic coated superconductor/copper interfaces at cryogenic temperatures

    E-print Network

    Ochterbeck, Jay Matthew

    1990-01-01

    THERMAL CONTACT CONDUCTANCE OF METALLIC COATED SUPERCONDUCTOR/COPPER INTERFACES AT CRYOGENIC TEMPERATURES A Thesis by JAY MATTHEW OCHTERBECK Submitted to the 0%ce of Graduate Studies of Texas AJrM IJniversity in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE August 1990 Major Subject: Mechanical Engineering THERMAL CONTACT CONDUCTANCE OF METALLIC COATED SUPERCONDUCTOR/COPPER INTERFACES AT CRYOGENIC TEMPERATURES A Thesis JA'r '(IATTHEW OCHTERBECK Approved...

  12. Apparatus for coating a surface with a metal utilizing a plasma source

    DOEpatents

    Brown, Ian G. (Berkeley, CA); MacGill, Robert A. (Richmond, CA); Galvin, James E. (Emeryville, CA)

    1991-01-01

    An apparatus and method for coating or layering a surface with a metal utilizing a metal vapor vacuum arc plasma source. The apparatus includes a trigger mechanism for actuating the metal vacuum vapor arc plasma source in a pulsed mode at a predetermined rate. The surface or substrate to be coated or layered is supported in position with the plasma source in a vacuum chamber. The surface is electrically biased for a selected period of time during the pulsed mode of operation of the plasma source. Both the pulsing of the metal vapor vacuum arc plasma source and the electrical biasing of the surface are synchronized for selected periods of time.

  13. Metal-Hydride Films with Switchable Optical Properties

    Microsoft Academic Search

    R. Griessen

    1997-01-01

    We have discovered^1,2 that yttrium-, lanthanum-, and rare-earth-hydride films exhibit spectacular changes in their optical properties when the hydrogen concentration is increased from 0 to 3. For example, a 500 nm thick YH2 film is metallic and shiny, while YH_3-delta is yellowish and transparent. The transition is reversible, fast, and can simply be induced by adding or removing hydrogen from

  14. High-rate reel-to-reel continuous coating of biaxially textured magnesium oxide thin films for coated conductors

    SciTech Connect

    Chudzik, M. P.; Erck, R. A.; Balachandran, U.; Luo, Z. P.; Miller, D. J.; Kannewurf, C. R.

    2000-01-12

    Biaxially textured thin films of magnesium oxide (MgO) were deposited by electron beam evaporation at deposition rates of 0.6 {mu}m/min on moving Ni-based alloy tapes as oriented buffer layers for coated conductors. Moving substrates were inclined with respect to the atomic vapor and translated through collimated dual vapor sources. Growth anisotropy in the MgO and self-shadowing effects due to the inclined angle combine to create biaxial texture in the deposited thin films. MgO films grown to a thickness of 2.0 {mu}m with this inclined-substrate deposition technique have yielded in-plane textures of 10--12{degree} fill-width half-maximum (FWHM). Results of a parametric study on the in-plane texture in short-length static-mode samples are presented, along with preliminary results of long-length samples deposited under translating conditions.

  15. Breakdown of ultrathin anodic valve metal oxide films in metal-insulator-metal-contacts compared with metal-insulator-electrolyte contacts

    Microsoft Academic Search

    Achim W. Hassel; Detlef Diesing

    2002-01-01

    The anodic breakdown of thin valve metal oxide films on aluminium, hafnium, niobium, titanium, tantalum and zirconium in the system valve-metal\\/valve-metal-oxide\\/silver was investigated. For all systems valve metal wires covered by an anodically formed oxide with an evaporated silver film were used. For comparison three different types of oxide were used in the case of aluminium: anodic oxide, gas phase

  16. Enhanced spin-dependent tunneling magnetoresistance in magnetite films coated by polystyrene

    NASA Astrophysics Data System (ADS)

    Wang, Wendong; Malkinski, Leszek; Tang, Jinke

    2007-05-01

    Hematite films were deposited by magnetron sputtering. A phase transformation from hematite to magnetite occurred when polystyrene (PS) coated hematite films were annealed above 200°C in hydrogen flow. Giant negative magnetoresistance (MR) was observed with the best MR ratio of over 8% (at room temperature and in a field of 5.5T) found in samples annealed at 230°C. The temperature dependence of the resistivity is characteristic of intergranular tunneling. After the PS layer was removed and the films annealed again at 230°C in hydrogen flow, the resistivity increased by about one order of magnitude and the MR ratio decreased to 4.3%. These data show that PS coating layer can protect magnetite films from oxidation and enhance interganular spin-dependent tunneling magnetoresistance.

  17. UV laser deposition of metal films by photogenerated free radicals

    NASA Technical Reports Server (NTRS)

    Montgomery, R. K.; Mantei, T. D.

    1986-01-01

    A novel photochemical method for liquid-phase deposition of metal films is described. In the liquid phase deposition scheme, a metal containing compound and a metal-metal bonded carbonyl complex are dissolved together in a polar solvent and the mixture is irradiated using a UV laser. The optical arrangement consists of a HeCd laser which provides 7 mW of power at a wavelength of 325 nm in the TEM(OO) mode. The beam is attenuated and may be expanded to a diameter of 5-20 mm. Experiments with photochemical deposition of silver films onto glass and quartz substrates are described in detail. Mass spectrometric analysis of deposited silver films indicated a deposition rate of about 1 A/s at incident power levels of 0.01 W/sq cm. UV laser-induced copper and palladium films have also been obtained. A black and white photograph showing the silver Van Der Pauw pattern of a solution-deposited film is provided.

  18. Corrosion-resistant amorphous metallic films of Mo/sub 49/Cr/sub 33/B/sub 18/ alloy

    SciTech Connect

    Ramesham, R.; DiStefano, S.; Fitzgerald, D.; Thakoor, A.P.; Khanna, S.K.

    1987-09-01

    Amorphous metallic films of Mo/sub 49/Cr/sub 33/B/sub 18/ have been deposited onto glass and quartz substrates by the magnetron sputter quenching technique. The amorphous nature of the as-deposited films was confirmed by their diffuse x-ray diffraction patterns. The crystallization temperature of the as-deposited films was 590/sup 0/C, according to the differential scanning calorimetry studies. Surface texture and cross-sectional features of the coatings were examined by scanning electron microscopy. Electron microprobe analysis was used to determine the chemical composition of the films. Chemical compositional uniformity of the as-deposited amorphous metallic films was verified by secondary ion mass spectrometry. As-deposited films exhibited microhardness of the order of 600-850 HV. Kinetics of corrosion of the alloy films in H/sub 2/SO/sub 4/ (1N) solution has been studied by potentiodynamic and galvanostatic techniques. As-deposited amorphous films exhibited corrosion current density three orders of magnitude less than the corrosion current density of 304 stainless steel in H/sub 2/SO/sub 4/ (1N) solution. A reaction mechanism at the corrosion potential is proposed.

  19. Single Wall Carbon Nano Tube Films and Coatings

    Microsoft Academic Search

    T. V. Sreekumar; Satish Kumar; Lars M. Ericson; Richard E. Smalley

    2002-01-01

    Purified single wall carbon nano tubes (SWNTs) produced from the high-pressure carbon monoxide (HiPCO) process have been dissolved \\/dispersed in oleum. These solutions \\/dispersions were optically homogeneous and have been used to form stand-alone SWNT films. The washed, dried, and heat-treated films are isotropic. The scanning electron micrographs of the film surface shows that the nanotube ropes (or fibrils) of

  20. Current sharing between the metallic and superconducting layers of high temperature superconductor coated conductors operated above their critical current

    NASA Astrophysics Data System (ADS)

    Bernstein, Pierre; McLoughlin, Conor; Thimont, Yohann; Sirois, Frédéric; Coulombe, Jonathan

    2011-02-01

    In this contribution, we report and discuss the physical meaning of pulse current measurements carried out on coated conductors (CCs) consisting of a superconducting YBCO film deposited on a Hastelloy substrate and coated with a thin metallic layer. The high current (up to 1000 A) and short duration pulses have allowed us to determine the current-voltage characteristics of two different samples in a situation near that of zero injected energy and therefore remove the bias resulting from the temperature rise during the measurement. The characteristics obtained show a flux creep region and two linear regimes. The first linear regime is the flux flow regime. In this regime, we show that there is a constant vortex velocity that depends on the metal film resistivity. The second linear regime is also a vortex regime, but its precise nature is less clear. We propose models describing both linear regimes, in agreement with the measurements. Finally, we discuss the consequences of these results for the applications of CCs in devices for power systems, especially fault current limiters and power transmission cables.

  1. FLUORESCENCE GAS SENSOR USING TiO2 NANOPARTICLES COATED WITH PORPHYRIN DYE THIN FILMS

    Microsoft Academic Search

    Nurul Huda Yusoff; Muhamad Mat Salleh; Muhammad Yahaya

    This paper explores the possibility of using fluorescence technique to detect the presence of volatile organic compounds based on TiO2 nanoparticles coated with porphyrin dye thin films. Porphyrin dye used was Iron (III) meso-tetraphenylporphine chloride. The thin films were prepared with the variation of TiO2 and porphyrin ratio, i.e. 1:2, 1:3, 1:4 and 1:5 by volume. The purpose of this

  2. Polycrystalline silicon thin-film solar cells on ZnO:Al-coated glass substrates

    Microsoft Academic Search

    S. Gall; C. Becker; K. Y. Lee; B. Rau; F. Ruske; B. Rech

    2009-01-01

    Polycrystalline Si (poly-Si) thin-film solar cells feature the potential to reach very high efficiencies at low costs. This paper addresses the development of poly-Si thin-film solar cells on ZnO:Al-coated glass substrates. This development is based on the fact that the properties of capped ZnO:Al layers stay the same (or even improve) upon annealing at temperatures far above the deposition temperature

  3. Transparent MgF 2-films by sol–gel coating: Synthesis and optical properties

    Microsoft Academic Search

    Hannes Krüger; Erhard Kemnitz; Andreas Hertwig; Uwe Beck

    2008-01-01

    Dielectric, anti-reflective or high reflective systems consist of low and high refractive index layers. Common systems are oxides. The preparation of low refractive index MgF2-films of optical quality by means of an anhydrous low temperature sol–gel synthesis is presented. The MgF2-sol is prepared by spin-coating on silicon and glass substrates. Various film thicknesses between 20 nm and 435 nm have been deposited.

  4. Properties of ITO on PET film in dependence on the coating conditions and thermal processing

    Microsoft Academic Search

    Michael Boehme; Christoph Charton

    2005-01-01

    Thin films of indium tin oxide (ITO) were deposited onto plastic web (PET) by reactive DC magnetron sputtering from a ceramic target of In2O3\\/SnO2 (90:10). The layer thickness and partial pressure of H2O were varied. After coating, the PET was heated up to 175 °C by various annealing steps. The films were then examined by XRD, SEM, UV\\/VIS\\/NIR spectroscopy, and

  5. SnO2 thin films prepared by dip-coating from microwave synthesized colloidal suspensions.

    PubMed

    Michel, E; Chaumont, D; Stuerga, D

    2003-01-15

    Tin(IV) oxide thin films have been prepared by dip-coating. The suspensions used for these depositions have been synthesized by microwave-induced thermohydrolysis of tin tetrachloride aqueous solutions in the presence of hydrochloric acid. Single or multiple depositions were tested, on glass substrates as well as on pure SiO2. The obtained thin films were characterized by optical microscopy, interferometric roughness measurements (Micromap), scanning electron microscopy, secondary ion mass spectroscopy, and scanning tunneling microscopy. PMID:16256478

  6. Carbon-coated film method PIXE for thick and insulating samples

    NASA Astrophysics Data System (ADS)

    Hideo, Ohashi; Yoshinobu, Koizumi; Koichi, Kobayashi

    1993-04-01

    We have developed a new and simple technique for thick, insulating samples for PIXE analysis. The sample was covered with a carbon-coated mylar film. The thickness of the mylar film was 2.7 ?m, and the carbon layer was less than 100 Å thick. This technique proved to be quite effective for eliminating sample charge buildup and also for sample current measurements.

  7. Ion-Plated Soft Metallic Films Reduce Friction and Wear

    NASA Technical Reports Server (NTRS)

    Spalvins, T.

    1986-01-01

    Ion plating is ion-assisted or glow-discharge surface-deposition technique. In this process, ions or energetic atoms transfer energy, momentum, and charge to substrate and deposited surface film. Process controlled to modify physical characteristics of surface, subsurface chemical conditions, and surface and subsurface microstructures as well. Ion plating with such soft, thin metallic films as gold, silver, or lead has great potential for producing self-contained lubricating surfaces. Such films reduce friction, wear, and corrosion on sliding or rotating mechanical surfaces used in wide range of environments.

  8. Metal films on polymer substrates stretched beyond 50%

    NASA Astrophysics Data System (ADS)

    Lu, Nanshu; Wang, Xi; Suo, Zhigang; Vlassak, Joost

    2007-11-01

    When a freestanding plastically deformable metal film is stretched, it ruptures by strain localization, and the elongation is less than a few percent. When the film is deposited on a polymer substrate, however, strain localization may be retarded by the substrate. This paper reports Cu films deposited on Kapton substrates and stretched up to the rupture of the substrates (at an elongation between 50% and 60%). When Cr adhesion layers are introduced between Cu and Kapton, few microcracks in Cu may be found, and the measured electrical resistance agrees with a theoretical prediction. Micrographs show that the strain localization and debonding coevolve.

  9. Effects of humidity during photoprocessing on thin film metallization adhesion

    SciTech Connect

    Norwood, D.P.

    1980-03-01

    Humidity effects during photoprocessing on tantalum/chromium/gold thin film networks (TFNs) were investigated. Humidity conditions at various process steps were controlled by placing either desiccant or water in handling containers for the TFNs. The TFNs photoprocessed in humid conditions had a much higher occurrence of metallization failures compared to TFNs processed in dry conditions. Ceramic surface defects were shown to cause pores in the thin films, and these pores enhanced corrosion susceptibility for the films. This study resulted in a desiccated storage process for production of TFNs.

  10. RAPID COMMUNICATION: YBCO thin films prepared by fluorine-reduced metal organic deposition using trifluoroacetates

    NASA Astrophysics Data System (ADS)

    Cui, X. M.; Tao, B. W.; Tian, Z.; Xiong, J.; Liu, X. Z.; Li, Y. R.

    2006-04-01

    Solution deposition is a promising method for YBCO coated conductor fabrication. We developed a new fluorine-reduced 'metal-organic deposition using trifluoroacetates' (TFA-MOD) method with copper acetate as one of the starting materials. Using the fluorine-reduced TFA-MOD method, we were able to get high performance YBCO films with good out-of-plane and in-plane orientations within a shortened calcining time, which was reduced by at least 4 h in comparison with that for the normal TFA-MOD process. Good superconducting properties, with Jc of 2 MA cm-2 at 77 K and Tc of 88.3 K (?Tc = 0.9 K), have been obtained for 350 nm epitaxial YBCO thin films on LaAlO3 single-crystal substrates. Owing to the low price of copper acetate and the shorter calcining time, fluorine-reduced TFA-MOD is a very effective and cost-cutting process.

  11. Superconducting Bi-Ca-Sr-Cu oxide thin films by spray pyrolysis of metal acetates

    NASA Astrophysics Data System (ADS)

    Vaslow, Dale F.; Dieckmann, Gunter H.; Elli, David Dawson; Ellis, Arthur B.; Holmes, D. Scott; Lefkow, Anthony; MacGregor, Mark; Nordman, James E.; Petras, Michael F.; Yang, Yifeng

    1988-07-01

    Superconducting Bi-Ca-Sr-Cu oxide thin films have been prepared on ZrO2-coated silicon (111) wafers by spray pyrolysis of metal acetate precursors followed by rapid annealing to 850 °C in air. Resistivity measurements indicate a broad superconducting transition with Tc onset near 90 K and zero resistivity below 60 K. The films are highly oriented with the c axis normal to the substrate surface and can be indexed to a tetragonal structure with lattice parameters of a=3.832(1) Å and c=30.78(5) Å. Both x-ray photoelectron spectroscopy and x-ray diffraction measurements indicate the loss of Ca to the ZrO2 buffer layer.

  12. Electrically Conductive, Corrosion-Resistant Coatings Through Defect Chemistry for Metallic Interconnects

    SciTech Connect

    Anil V. Virkar

    2006-12-31

    The principal objective of this work was to develop oxidation protective coatings for metallic interconnect based on a defect chemistry approach. It was reasoned that the effectiveness of a coating is dictated by oxygen permeation kinetics; the slower the permeation kinetics, the better the protection. All protective coating materials investigated to date are either perovskites or spinels containing metals exhibiting multiple valence states (Co, Fe, Mn, Cr, etc.). As a result, all of these oxides exhibit a reasonable level of electronic conductivity; typically at least about {approx}0.05 S/cm at 800 C. For a 5 micron coating, this equates to a maximum {approx}0.025 {Omega}cm{sup 2} area specific resistance due to the coating. This suggests that the coating should be based on oxygen ion conductivity (the lower the better) and not on electronic conductivity. Measurements of ionic conductivity of prospective coating materials were conducted using Hebb-Wagner method. It was demonstrated that special precautions need to be taken to measure oxygen ion conductivity in these materials with very low oxygen vacancy concentration. A model for oxidation under a protective coating is presented. Defect chemistry based approach was developed such that by suitably doping, oxygen vacancy concentration was suppressed, thus suppressing oxygen ion transport and increasing effectiveness of the coating. For the cathode side, the best coating material identified was LaMnO{sub 3} with Ti dopant on the Mn site (LTM). It was observed that LTM is more than 20 times as effective as Mn-containing spinels. On the anode side, LaCrO3 doped with Nb on the Cr site (LNC) was the material identified. Extensive oxidation kinetics studies were conducted on metallic alloy foils with coating {approx}1 micron in thickness. From these studies, it was projected that a 5 micron coating would be sufficient to ensure 40,000 h life.

  13. Improved Cutting Processes with Adapted Coating Systems

    Microsoft Academic Search

    F. Klocke; T. Krieg; K. Gerschwiler; R. Fritsch; V. Zinkann; M. Pöhls; G. Eisenblätter

    1998-01-01

    Since the introduction of coated metal cutting tools, there has been continuous development and improvement of substrates and coatings. These improvements are invariably aimed at better resistance to the stresses involved in specific cutting tasks like interrupted cutting, machining of adhesive materials or hard and dry machining. Examples of improved performance coatings include multilayer hard thin films or composite hard\\/soft

  14. Role of vacuum fluctuation forces in thin metal film stability

    E-print Network

    Andrea Benassi; Carlo Calandra

    2008-08-18

    Thin metal films are subject to the pressure caused by the zero point oscillations of the electromagnetic field, which depends upon the film optical properties and, in case of deposition onto a substrate, upon the substrate reflectivity. It has been suggested that this force may be relevant in determining the stability of deposited pseudomorphic films with respect to buckling or island formation. We present a detailed analysis of its behaviour as a function of the optical parameters and of the film thickness and we illustrate the conditions under which it may play some role. For free standing films it turns out that the film stabilization is basically due to the surface stress, which largely overwhelms the vacuum force. For epilayers on metal substrate the vacuum force may be important, and we give stability diagrams and critical thicknesses for several cases, illustrating how the flat surface growth may depend upon the film parameters. The importance of including retardation effects into the theory for a realistic determination of the stability conditions is also discussed.

  15. Films loaded with insulin-coated nanoparticles (ICNP) as potential platforms for peptide buccal delivery.

    PubMed

    Morales, Javier O; Huang, Siyuan; Williams, Robert O; McConville, Jason T

    2014-10-01

    The goal of this investigation was to develop films containing insulin-coated nanoparticles and evaluate their performance in vitro as potential peptide delivery systems. To incorporate insulin into the films, a new antisolvent co-precipitation fabrication process was adapted to obtain insulin-coated nanoparticles (ICNPs). The ICNPs were embedded in polymeric films containing a cationic polymethacrylate derivative (ERL) or a combination of ERL with hydroxypropyl methylcellulose (HPMC). ICNP-loaded films were characterized for morphology, mucoadhesion, and insulin release. Furthermore, in vitro insulin permeation was evaluated using a cultured tridimensional human buccal mucosa model. The antisolvent co-precipitation method was successfully adapted to obtain ICNPs with 40% (w/w) insulin load, achieving 323±8nm particles with a high zeta potential of 32.4±0.8mV, indicating good stability. High yields were obtained after manufacture and the insulin content did not decrease after one month storage. ICNP-embedded films using ERL as the polymer matrix presented excellent mucoadhesive and insulin release properties. A high permeation enhancement effect was observed for ICNP-loaded ERL films in comparison with ICNP-loaded ERL-HPMC films and a control insulin solution. ICNP-loaded ERL formulations were found to be more effective in terms of film performance and insulin permeation through the human buccal mucosa model, and thus are a promising delivery system for buccal administration of a peptide such as insulin. PMID:25016543

  16. Antimicrobial and enzymatic antibrowning film used as coating for bamboo shoot quality improvement.

    PubMed

    Badwaik, Laxmikant S; Borah, Pallab Kumar; Deka, Sankar C

    2014-03-15

    Edible films were prepared with varying proportion of alginate and starch in the ratio of 2:0(F1), 2:1(F2), 1:1(F3), 1:1.5(F4), 1:2(F5), 0:2(F6) with added carboxymethyl cellulose (15%, w/w of starch). The film F5 had superior barrier, mechanical and thermal properties over the other films. Water vapor permeability, moisture absorption, water solubility, breakage strength and elongation capacity of F5 film were reported as 1.21 × 10(-9)g/Pa h m, 9.37%, 40%, 977.3g and 14.62 mm respectively. However, surface characteristics showed the smooth and uniform film and thermal decomposition took place above 200 °C. The film forming solution of selected F5 film, added with antioxidant and antimicrobial extracts was coated on bamboo shoots and stored for 5 days. The film was successful in lowering the browning of bamboo shoots, and also successfully inhibited surface microbial load. Moreover, the moisture loss of coated shoot was less compared to uncoated. PMID:24528722

  17. Development of an all-metal thick film cost effective metallization system for solar cells

    Microsoft Academic Search

    B. Ross; J. Parker

    1983-01-01

    Improved thick film solar cell contacts for the high volume production of low cost silicon solar arrays are needed. All metal screenable pastes made from economical base metals and suitable for application to low to high conductivity silicon were examined. Silver fluoride containing copper pastes and fluorocarbon containing copper pastes were discussed. The effect of hydrogen on the adhesion of

  18. Tribological coatings for liquid metal and irradiation environments

    Microsoft Academic Search

    R. N. Johnson

    1986-01-01

    Several metallurgical coatings have been developed that provide good tribological performances in high-temperature liquid\\u000a sodium and that are relatively unaffected by neutron fluences to 6 × 1022 n\\/cm2 (E >0.1 MeV). The coatings that have consistently provided the best tribological performance have been the nickel aluminide diffusion\\u000a coatings created by the pack cementation process, chromium carbide or Tribaloy 700 (a

  19. Erosion of mylar and protection by thin metal films

    NASA Technical Reports Server (NTRS)

    Fraundorf, P.; Lindstrom, D.; Sandford, S.; Swan, P.; Walker, R.; Zinner, E.; Pailer, N.

    1983-01-01

    Mylar strips, 2.5 microns thick, uncoated and coated with 50A, 100A and 200A of Al, Pd, and Au/Pd were exposed on STS-5 in order to measure the erosion of mylar and to test means of protecting thin plastic foils commonly used for space experiments in low earth orbit. Analysis by optical microscopy, SEM and STEM investigation, EDX measurements, FTIR spectroscopy and weight loss measurements showed that while up to 75 percent of the uncoated mylar was eroded during exposure, thin coatings of the above metals can protect mylar for integrated oxygen-fluxes of at least 10 to the 21st atoms/sq cm.

  20. Effects of interfacial properties on the ductility of polymer-supported metal films for flexible electronics

    Microsoft Academic Search

    W. Xu; T. J. Lu; F. Wang

    2010-01-01

    Polymer-supported metal films as interconnects for flexible, large area electronics may rupture when they are stretched, and the rupture strain is strongly dependent upon the film\\/substrate interfacial properties. This paper investigates the influence of interfacial properties on the ductility of polymer-supported metal films by modeling the microstructure of the metal film as well as the film\\/substrate interface using the method

  1. Self-healing of capacitors with metallized film technology

    Microsoft Academic Search

    J. H Tortai; A Denat; N Bonifaci

    2001-01-01

    Capacitors made of metallized polypropylene films suffer partial discharges, called self-healing, due to weak electrical defects. Those defects are destroyed by an electrical arc that extinguishes when enough metal of the electrodes is vapourized around this point. From experimental results, we have elaborated a model of the self-healing phenomenon. The present work shows that the volatilized area of self-healing is

  2. Micro-nanoprobing measurement of polymer coating/film mechanical properties

    NASA Astrophysics Data System (ADS)

    Xia, Xinyun (Sherry)

    2000-10-01

    The goals of this study are (1) to demonstrate the applications of nanoindentation for mechanical properties studies of polymer coating/film systems; (2) to develop and verify viscoelastic analytical solutions for indentation on polymers; (3) to advance nanoindentation technique for better understanding of coating processes, particularly under drying conditions. To meet the project goals, several polymer coating/film systems are studied during or after drying and curing. First, the demonstration experiments were mainly conducted on near-surface structure formation of chemically imidized polyimide films. Nanoindentation method successfully explained the peel strength difference observed in industry by distinguishing variation of microstructure related modulus difference between two sides of films with different annealing temperature. Second, to verify a linear viscoelastic analytical solutions based on standard solids model developed by Cheng et al, indentation creep and relaxation tests with flat-ended punch and spherical indenter were conducted on polystyrene, photographic protecting coatings and polyvinyl alcohol coatings (PVOH). The coatings' young's modulus and viscosity obtained were similar to literature values. The application of these solutions to PVOH coatings also successfully helped to distinguish the near surface crystallinity difference formed during the drying process. Furthermore, humidity and temperature control accessories are set up for Hysitron to extend the capability of nanoindentation method on in situ coating mechanical properties study. Influence on mechanical properties of drying semicrystalline PVOH coating with different molecular weight under different humidity was studied. The work first relates the near-surface mechanical property to solvent induced surface crystallinity during process and indicates that such approaches will help to optimize drying processes and coating microstructure control. To demonstrate the application of the temperature stage, an initial study on temperature effect on the PVOH coating surface adhesion using pull-off force during indentation was carried out. For indentation, adhesion energy between the indenter and sample surface will influence the contact area determination and eventually the measured mechanical properties. It is also an important issue to the fields where interactions at and across the interface operate. This study makes it possible to study surface adhesion energy of small-scale features using nanoindentation.

  3. Finite-difference time-domain modeling of nonperfectly conducting metallic thin-film gratings

    SciTech Connect

    Judkins, J.B.; Ziolkowski, R.W. [Electromagnetics Laboratory, Department of Electrical and Computer Engineering, University of Arizona, Tucson, Arizona 85721 (United States)

    1995-09-01

    A simulation tool based on the finite-difference time-domain (FDTD) technique is developed to model the electromagnetic interaction of a focused optical Gaussian beam in two dimensions incident on a simple model of a corrugated dielectric surface plated with a thin film of realistic metal. The technique is a hybrid approach that combines an intensive numerical method near the surface of the grating, which takes into account the optical properties of metals, with a free-space transform to obtain the radiated fields. A description of this technique is presented along with numerical examples comparing gratings made with realistic and perfect conductors. In particular, a demonstration is given of an obliquely incident beam focused on a uniform grating and a normally incident beam focused on a nonuniform grating. The gratings in these two cases are coated with a negative-permittivity thin film, and the scattered radiation patterns for these structures are studied. Both TE and TM polarizations are investigated. Using this hybrid FDTD technique results in a complete and accurate simulation of the total electromagnetic field in the near field as well as in the far field of the grating. It is shown that there are significant differences in the performances of the realistic metal and the perfect metal gratings.

  4. Adherent diamond like carbon coatings on metals via plasma source ion implantation

    SciTech Connect

    Walter, K.C.; Nastasi, M.; Munson, C.P.

    1996-12-01

    Various techniques are currently used to produce diamond-like carbon (DLC) coatings on various materials. Many of these techniques use metallic interlayers, such as Ti or Si, to improve the adhesion of a DLC coating to a ferrous substrate. An alternative processing route would be to use plasma source ion implantation (PSII) to create a carbon composition gradient in the surface of the ferrous material to serve as the interface for a DLC coating. The need for interlayer deposition is eliminated by using a such a graded interfaces PSII approach has been used to form adherent DLC coatings on magnesium, aluminum, silicon, titanium, chromium, brass, nickel, and tungsten. A PSII process tailored to create a graded interface allows deposition of adherent DLC coatings even on metals that exhibit a positive heat of formation with carbon, such as magnesium, iron, brass and nickel.

  5. Contact Angle of Glass Substrate Coated with TiO2\\/SiO2 Thin Film

    Microsoft Academic Search

    Jiraporn Damchan; Lek Sikong; Kalayanee Kooptarnond; Sutham Niyomwas

    The self- cleaning effect in terms of contact angle value and photocata- lytic activity of SiO2\\/TiO2 thin films coated on glass substrate was measured. The composite thin films were prepared by means of spin coating and calcina - tions at the temperature 500°C for 2 h. The microstructure of pure TiO2 and SiO2\\/TiO2 composite film were characterized by using AFM.

  6. Characterization of gas-phase adsorption on metal oxide thin films using a magnetoelastic resonance microbalance.

    PubMed

    Zorn, Michael E; Rahne, Kari A; Tejedor-Tejedor, M Isabel; Anderson, Marc A; Grimes, Craig A

    2003-11-15

    In this study, a magnetoelastic resonance microbalance (MERM) was used to directly measure the gas-phase adsorption behavior of water vapor, isopropyl alcohol, and acetone on a sol-gel-derived titanium dioxide sensor coating. The nature of the MERM platform enables chemical measurements in situations in which wires or physical connections are undesired (or not possible) or in which sensor cost is a major issue. The underlying MERM technique (with an uncoated sensor) showed excellent day-to-day stability, a linear calibration over a 1 kHz change in frequency (or a 1.5-mg change in mass), and the ability to detect a mass change of 15 microg without any efforts at sensitivity optimization. The titanium dioxide coated sensor yielded excellent response to each of the analytes; however, the response did not follow a simple linear calibration function. A more complex calibration model or utilization of the coated sensor in a limited concentration range would be required for quantitative analysis. The process of applying the metal oxide coatings onto the magnetic substrate altered the structure of the thin film layer, resulting in a relatively loose packing of the porous primary titanium dioxide particles to create an open overall honeycomb structure, thereby affecting the adsorption behavior at high relative concentration. PMID:14616005

  7. Texture etched ZnO:Al coated glass substrates for silicon based thin film solar cells

    Microsoft Academic Search

    O. Kluth; B Rech; L Houben; S Wieder; G Schöpe; C Beneking; H Wagner; A Löffl; H. W Schock

    1999-01-01

    ZnO:Al films were r.f.- and d.c.-magnetron sputtered on glass substrates from ceramic (ZnO:Al2O3) and metallic (Zn:Al) targets, respectively. The initially smooth films exhibit high transparencies (T?83% for visible light including all reflection losses) and excellent electrical properties (?=2.7–6×10?4 ? cm). Depending on their structural properties these films develop different surface textures upon post deposition etching in diluted HCl. The light

  8. Metal oxide\\/hydroxide-coated dual-media filter for simultaneous removal of bacteria and heavy metals from natural waters

    Microsoft Academic Search

    M. Mansoor Ahammed; V. Meera

    2010-01-01

    The present study was conducted to compare the performance of a dual-media filter consisting of manganese oxide-coated (MOCS) and iron hydroxide-coated sand (IOCS) with that of IOCS filter and uncoated sand filter in treating water contaminated by microorganisms, heavy metals and turbidity with a view to its use in simple household water purification devices in developing countries. Long-duration column tests

  9. Nafion-coated mercury thin film electrodes for batch-injection analysis with anodic stripping voltammetry.

    PubMed

    Brett, C M; Maria Oliveira Brett, A; Matysik, F M; Matysik, S; Kumbhat, S

    1996-11-01

    Batch-injection analysis exhibits the advantages of rapid and simple electroanalysis of microlitre samples. Nafion-coated mercury thin film electrodes have been evaluated for use in batch-injection analysis with anodic stripping voltammetry (BIA-ASV). The advantages of Nafion-coated electrodes in reducing electrode contamination by components of complex matrices are combined with the analysis of small microlitre sample volumes. The measurement of traces of lead and cadmium is used to illustrate the approach. An optimised procedure for formation of Nafion-coated mercury thin film electrodes is evolved. The relative sensitivity for BIA-ASV at electrodes with and without Nafion coatings is 0.9 and 0.8 for cadmium and lead respectively; detection limits are 2 x 10(-9) M and 4 x 10(-9) M. Studies were done concerning the influence of surfactants and their effect was found to be much less with the Nafion film coating. Applications to real environmental samples are demonstrated. PMID:18966693

  10. VO2 films with strong semiconductor to metal phase transition prepared by the precursor oxidation process

    E-print Network

    Luryi, Serge

    VO2 films with strong semiconductor to metal phase transition prepared by the precursor oxidation, the precursor oxidation process, for making VO2 films with strong semiconductor-to-metal phase transition. Sputter-deposited metal precursor V films were oxidized in situ in the deposition chamber for 2.5­7 h

  11. Effect of metal films on the photoluminescence and electroluminescence of conjugated polymers

    Microsoft Academic Search

    H. Becker; S. E. Burns; R. H. Friend

    1997-01-01

    We report the modification of photoluminescence (PL) and electroluminescence (EL) from conjugated polymers due to the proximity of metal films. The presence of a metal film alters the radiative decay rate of an emitter via interference effects, and also opens up an efficient nonradiative decay channel via energy transfer to the metal film. We show that these effects lead to

  12. Improvement of boundary lubrication properties of diamond-like carbon (DLC) films due to metal addition

    Microsoft Academic Search

    Shojiro Miyake; Tadashi Saito; Yoshiteru Yasuda; Yusuke Okamoto; Makoto Kano

    2004-01-01

    The effects of added materials such as metals like titanium (Ti), molybdenum (Mo) and iron (Fe) diamond-like carbon (DLC) films on boundary lubrication and microtribological properties were investigated. The nanoindentation hardness and microwear resistance can be improved by adding the proper metal to DLC films, as evaluated by atomic force microscopy (AFM). Boundary lubrication properties of DLC films with metals

  13. A Theoretical Study of Instabilities at the Advancing Front of Thermally Driven Coating Films

    Microsoft Academic Search

    Dawn E. Kataoka; Sandra M. Troian

    1997-01-01

    A thin liquid coating can spread vertically beyond the equilibrium meniscus position by the application of a temperature gradient to the adjacent substrate. So called super-meniscus films experience a surface shear stress which drives flow toward regions of higher surface tension located at the cooler end of the substrate. The Marangoni stresses responsible for this spreading process can also be

  14. Normal spectral emittance of Inconel 718 aeronautical alloy coated with yttria stabilized zirconia films

    Microsoft Academic Search

    L. González-Fernández; L. del Campo; R. B. Pérez-Sáez; M. J. Tello

    Knowledge of the radiative behaviour of the yttria stabilized zirconia (YSZ) thermal barrier coatings (TBCs) is needed to perform radiative heat transfer calculations in industrial applications. In this paper, normal spectral emittance experimental data of atmospheric plasma sprayed (PS) YSZ films layered on Inconel 718 substrates are shown. The spectral emittance was measured between 2.5 and 22?m on samples with

  15. Sputtered silver films to improve chromium carbide based solid lubricant coatings for use to 900 C

    NASA Technical Reports Server (NTRS)

    Dellacorte, Christopher; Sliney, Harold E.; Deadmore, Daniel L.

    1988-01-01

    Thin silver films, 250 to 3500 A thick, were sputtered onto PS200, a plasma sprayed, chromium carbide based solid lubricant coating, to reduce run-in wear and improve tribological properties. The coating contains bonded chromium carbide as the wear resistant base stock with silver and barium fluoride/calcium fluoride eutectic added as low and high temperature lubricants, respectively. Potential applications for the PS200 coating are cylinder wall/piston ring lubrication for Stirling engines and foil bearing journal lubrication. In this preliminary program, the silver film overlay thickness was optimized based on tests using a pin-on-disk tribometer. The friction and wear studies were performed in a helium atmosphere at temperatures from 25 to 760 C with a sliding velocity of 2.7 m/s under a 4.9 N load. Films between 1000 and 1500 A provide the best lubrication of the counterface material. The films enrich the sliding surface with lubricant and reduce the initial abrasiveness of the as ground, plasma-sprayed coating surface, thus reducing wear.

  16. Sputtered silver films to improve chromium carbide based solid lubricant coatings for use to 900 C

    NASA Technical Reports Server (NTRS)

    Dellacorte, Christopher; Sliney, Harold E.; Deadmore, Daniel L.

    1988-01-01

    Thin silver films, 250 to 3500 A thick, were sputtered onto PS200, a plasma sprayed, chromium carbide based solid lubricant coating, to reduce run-in wear and improve tribological properties. The coating contains bonded chromium carbide as the wear resistant base stock with silver and barium fluoride/calcium fluoride eutectic added as low and high temperature lubricants respectively. Potential applications for the PS200 coating are cylinder wall/piston ring lubrication for Stirling engines and foil bearing journal lubrication. In this preliminary program, the silver film overlay thickness was optimized based on tests using a pin-on-disk tribometer. The friction and wear studies were performed in a helium atmosphere at temperatures from 25 to 760 C with a sliding velocity of 2.7 m/s under a 4.9 N load. Films between 1000 and 1500 A provide the best lubrication of the counterface material. The films enrich the sliding surface with lubricant and reduce the initial abrasiveness of the as ground, plasma-sprayed coating surface, thus reducing wear.

  17. Helium irradiation effects on retention behavior of deuterium implanted into boron coating film by PCVD

    Microsoft Academic Search

    H. Kodama; M. Oyaidzu; A. Yoshikawa; H. Kimura; Y. Oya; M. Matsuyama; A. Sagara; N. Noda; K. Okuno

    2005-01-01

    Helium irradiation effects on the retention of energetic deuterium implanted into the boron coating film were investigated by means of X-ray photoelectron spectroscopy (XPS) and thermal desorption spectroscopy (TDS). It was found, by XPS, that the B 1s peak was shifted to lower binding energy side by He+ ion irradiation and the FWHM was extended. These facts show that the

  18. Fatigue Properties and Fracture Mechanism of Steel Coated with Diamond-Like Carbon Films

    NASA Astrophysics Data System (ADS)

    Akebono, Hiroyuki; Kato, Masahiko; Sugeta, Atsushi

    Diamond-like carbon (DLC) films have attracted much attention in many industrial fields because of their excellent tribological properties, high hardness, chemical inertness and biocompatibility. In order to examine the fatigue properties and to clear the fracture mechanism of DLC coated materials, AISI4140 steel coated with DLC films by using unbalanced magnetron sputtering method was prepared and two types of fatigue test were carried out by using a tension and compression testing machine with stress ratio -1 and a bending testing machine with stress ratio -1 with a focused on the fatigue crack behavior in detail. The fracture origin changed from the slip deformation to micro defects at surface whose size didn't affect the fatigue crack initiation behavior in the case of Virgin series because the hard coating like DLC films make the defect sensitivity of coated material higher. However, DLC series indicated higher fatigue strengths in finite life region and fatigue limit compared with Virgin series. From the continuously observation by using a plastic replicas technique, it is clear that there are no noticeable differences on fatigue crack propagation rate between the Virgin and DLC series, however the fatigue crack initiation of DLC series was delayed significantly by existence of DLC films compared with Virgin series.

  19. Enhancement of evanescent fluorescence from fiber optic sensors by thin film sol gel coatings

    Microsoft Academic Search

    H. P. Kao; N. Yang; J. S. Schoeniger

    1997-01-01

    A theoretical analysis and experimental demonstration of the increase in collected evanescent fluorescence for a fiber optic sensor having a high refractive index, titanium sol gel, thin film coating is presented. Collected fluorescence increased by up to 6 X over that from a bare fiber having a numerical aperture of 0.60. The maximum collected fluorescence increased and shifted to smaller

  20. Structural and electrical properties of sol-gel spin coated indium doped cadmium oxide thin films

    SciTech Connect

    Rajammal, R. [Department of Physics, M.V.M Govt. Arts College for Women, Dindigul-624001 (India); Savarimuthu, E., E-mail: savari56@gmail.com; Arumugam, S., E-mail: savari56@gmail.com [Department of Physcis, Gandhigram Rural Institute, Gandhigram-624302 (India)

    2014-04-24

    The indium doped CdO thin films have been prepared by the sol-gel spin coating technique and the influence of indium doping concentration on the structural and electrical properties of the deposited films has been investigated. The indium doping concentration in the solution has been varied from 0-10 wt% insteps of 2wt%. A indium doping concentration of 6wt% has been found to be optimum for preparing the films and at this stage a minimum resistivity of 5.92×10{sup ?4}? cm and a maximum carrier concentration of 1.20×10{sup 20}cm{sup ?3} have been realized.

  1. Optical Reflectance Of Metallic Coatings: Effect Of Aluminum Flake Orientation

    Microsoft Academic Search

    Li-Piin Sung; Maria E. Nadal; Mary E. McKnight; Egon Marx; Brent Laurenti

    2001-01-01

    A set of aluminum-flake pigmented coatings having different flake orientations was pre- pared using various spray conditions. The orientations of individual flakes were determined from images obtained by laser scanning confocal microscopy. Reflectance measurements were carried out to quantify the optical properties of the coatings. A Gaussian orientation distribution or topographic map of the flakes was then used as input

  2. Polymer blend lithography for metal films: large-area patterning with over 1 billion holes/inch2

    PubMed Central

    Huang, Cheng; Förste, Alexander; Schimmel, Thomas

    2015-01-01

    Summary Polymer blend lithography (PBL) is a spin-coating-based technique that makes use of the purely lateral phase separation between two immiscible polymers to fabricate large area nanoscale patterns. In our earlier work (Huang et al. 2012), PBL was demonstrated for the fabrication of patterned self-assembled monolayers. Here, we report a new method based on the technique of polymer blend lithography that allows for the fabrication of metal island arrays or perforated metal films on the nanometer scale, the metal PBL. As the polymer blend system in this work, a mixture of polystyrene (PS) and poly(methyl methacrylate) (PMMA), dissolved in methyl ethyl ketone (MEK) is used. This system forms a purely lateral structure on the substrate at controlled humidity, which means that PS droplets are formed in a PMMA matrix, whereby both phases have direct contact both to the substrate and to the air interface. Therefore, a subsequent selective dissolution of either the PS or PMMA component leaves behind a nanostructured film which can be used as a lithographic mask. We use this lithographic mask for the fabrication of metal patterns by thermal evaporation of the metal, followed by a lift-off process. As a consequence, the resulting metal nanostructure is an exact replica of the pattern of the selectively removed polymer (either a perforated metal film or metal islands). The minimum diameter of these holes or metal islands demonstrated here is about 50 nm. Au, Pd, Cu, Cr and Al templates were fabricated in this work by metal PBL. The wavelength-selective optical transmission spectra due to the localized surface plasmonic effect of the holes in perforated Al films were investigated and compared to the respective hole diameter histograms.

  3. Novel Nanocrystalline Intermetallic Coatings for Metal Alloys in Coal-fired Environments

    SciTech Connect

    Z. Zak Fang; H. Y. Sohn

    2009-08-31

    Intermetallic coatings (iron aluminide and nickel aluminide) were prepared by a novel reaction process. In the process, the aluminide coating is formed by an in-situ reaction between the aluminum powder fed through a plasma transferred arc (PTA) torch and the metal substrate (steel or Ni-base alloy). Subjected to the high temperature within an argon plasma zone, aluminum powder and the surface of the substrate melt and react to form the aluminide coatings. The prepared coatings were found to be aluminide phases that are porosity-free and metallurgically bonded to the substrate. The coatings also exhibit excellent high-temperature corrosion resistance under the conditions which simulate the steam-side and fire-side environments in coal-fired boilers. It is expected that the principle demonstrated in this process can be applied to the preparation of other intermetallic and alloy coatings.

  4. Depth profile of residual stress in metal-ion implanted TiN coatings

    Microsoft Academic Search

    David Rafaja; Václav Valvoda; Anthony J. Perry; James R. Treglio

    1997-01-01

    Titanium nitride coatings made by conventional CVD were implanted with metal ions of different species at various energies. Changes occurring in the host structure after the ion implantation were studied using grazing incidence X-ray diffraction. One consequence of the metal ion implantation was an increase of the compressive residual stress in the implantation affected zone. The depth profile of the

  5. Nanoscale growth twins in sputtered metal films

    NASA Astrophysics Data System (ADS)

    Zhang, X.; Anderoglu, O.; Hoagland, R. G.; Misra, A.

    2008-09-01

    This article reviews recent studies on the mechanical properties of sputtered copper and 330 stainless-steel films with {111} nanoscale growth twins preferentially oriented perpendicular to growth direction. The mechanisms of formation of growth twins during sputtering, unusually high strengths, and excellent thermal stability of nanotwinned structures are highlighted.

  6. Laser generation of ultrasound in films and coatings

    NASA Astrophysics Data System (ADS)

    Murray, T. W.; Krishnaswamy, S.; Achenbach, J. D.

    1999-06-01

    A model for the pulsed laser generation of ultrasound in an isotropic film on a semi-infinite substrate is presented. The model gives the time domain displacement of the system as a function of the density and mechanical properties of the film and substrate and the thermal properties of the film. The model has been verified experimentally using a 1 ns Nd:YAG laser source for acoustic wave generation and a stabilized Michelson interferometer for detection. Experimental and theoretical signals agree well for both the case of a fast layer on a slow substrate (zirconium nitride/steel) and a slow layer on a fast substrate (titanium/aluminum).

  7. Photon management by metallic nanodiscs in thin film solar cells

    Microsoft Academic Search

    Carsten Rockstuhl; Falk Lederer

    2009-01-01

    We investigate the absorption enhancement by metallic nanodiscs in thin-film amorphous silicon solar cells. The effect is quantitatively evaluated by rigorously solving Maxwell's equations. We show that 50% more photons can be absorbed using geometries accessible for current nanofabrication technologies. Moreover, the thinner the solar cell, the larger the absorption enhancement. Detailed investigations prove that the enhancement can be related

  8. Negative group velocity of surface plasmons on thin metallic films

    Microsoft Academic Search

    Yongmin Liu; David F. P. Pile; Zhaowei Liu; Dongmin Wu; Cheng Sun; Xiang Zhang

    2006-01-01

    By tailoring the dispersion curve of surface plasmons (SPs) of a thin metallic film surrounded by dielectric half-spaces, it is shown that the group velocity of the symmetric mode is always positive, while the group velocity of the anti-symmetric mode can be negative. Consequently, the forward and backward propagation of SPs, in which the energy flow is respectively parallel or

  9. Thermal simulation for geometric optimization of metallized polypropylene film capacitors

    Microsoft Academic Search

    M. H. El-Husseini; Pascal Venet; Gérard Rojat; Charles Joubert

    2002-01-01

    In this paper, the authors use an analytical model to calculate the losses in the metallized polypropylene film capacitors. The model is validated experimentally for capacitors having the same capacitance but different geometry. For each group of capacitors, a temperature distribution in the roll is assumed with the aim of optimizing its thermal performance. It appears that the heating of

  10. Alginate- and gellan-based edible films for probiotic coatings on fresh-cut fruits.

    PubMed

    Tapia, M S; Rojas-Graü, M A; Rodríguez, F J; Ramírez, J; Carmona, A; Martin-Belloso, O

    2007-05-01

    Alginate- (2% w/v) or gellan-based (0.5%) edible films, containing glycerol (0.6% to 2.0%), N-acetylcysteine (1%), and/or ascorbic acid (1%) and citric acid (1%), were formulated and used to coat fresh-cut apple and papaya cylinders. Water vapor permeability (WVP) was significantly higher (P < 0.05) in alginate films (0.30 to 0.31 x 10(-9) g m/Pa s m2) than in the gellan ones (0.26 to 0.27 x 10(-9) g m/Pa s m2). Addition of 0.025% (w/v) sunflower oil decreased WVP of gellan films (0.20 to 0.22 x 10(-9) g m/Pa s m2). Water solubility of gellan and alginate films at 25 degrees C (0.47 to 0.59 and 0.74 to 0.79, respectively) and their swelling ratios (2.3 to 2.6 and 1.6 to 2.0, respectively) indicate their potential for coating high moisture fresh-cut fruits. Fresh-cut apple and papaya cylinders were successfully coated with 2% (w/v) alginate or gellan film-forming solutions containing viable bifidobacteria. WVP in alginate (6.31 and 5.52 x 10(-9) g m/Pa s m2) or gellan (3.65 and 4.89 x 10(-9) g m/Pa s m2) probiotic coatings of papaya and apple, respectively, were higher than in the corresponding cast films. The gellan coatings and films exhibited better water vapor properties in comparison with the alginate coatings. Values > 10(6) CFU/g B. lactis Bb-12 were maintained for 10 d during refrigerated storage of fresh-cut fruits, demonstrating the feasibility of alginate- and gellan-based edible coatings to carry and support viable probiotics on fresh-cut fruit. PMID:17995771

  11. Refractive index sensitivity of nano-film coated long-period fiber gratings.

    PubMed

    Zou, Fang; Liu, Yunqi; Deng, Chuanlu; Dong, Yanhua; Zhu, Shan; Wang, Tingyun

    2015-01-26

    We demonstrate the fabrication of long-period fiber gratings (LPFGs) coated with high index nano-film using the atomic layer deposition (ALD) technology. Higher index sensitivity can be achieved in the transition region of the coated LPFGs. For the LPFG coated by nano-film with a thickness of 100 nm, the high index sensitivity of 3000 nm/RIU and the expanded index sensitive range are obtained. The grating contrast of the over-coupled LPFGs and conventional LPFGs are measured and the over-coupled gratings are found to have a higher contrast in the transition region. The cladding modes transition is observed experimentally with increasing surrounding index using an infrared camera. The theoretical model of the hybrid modes in four-layer cylindrical waveguide is proposed for numerical simulation. The experimental results are well consistent with theoretical analysis. PMID:25835871

  12. A travelling photothermal technique employing pyroelectric detection to measure thermal diffusivity of films and coatings.

    PubMed

    Philip, J; Manjusha, M V; Soumya, H

    2011-10-01

    A travelling thermal wave technique employing optical excitation and pyroelectric detection of thermal waves propagating along a material film/coating on a substrate is described. The method enables direct measurement of thermal diffusivity. The technique involves measurement of the phase lag undergone by an optically excited thermal wave as it propagates along the coating. The set up has been automated for convenient and fast data acquisition and analysis. The technique has been adapted to measurement of thermal diffusivity of a commercial paint sample coated on glass and copper substrates. It is found that thermal diffusivity of the coating is independent of the thermal conductivity of the substrate. Dependence of thermal diffusivity on coating thickness shows exponential increase, with value reaching a constant at a characteristic high thickness. Measurements have been carried out on a few other samples with wide variations in thermal diffusivity, and the results compared with available reports or results obtained following other techniques. Analyses of the results show that the technique allows measurement of thermal diffusivity of coatings and films with uncertainties better than ±2.5%. PMID:22047317

  13. Ellipsometric Measurement of Bacterial Films at Metal-Electrolyte Interfaces

    PubMed Central

    Busalmen, J. P.; de Sánchez, S. R.; Schiffrin, D. J.

    1998-01-01

    Ellipsometric measurements were used to monitor the formation of a bacterial cell film on polarized metal surfaces (Al-brass and Ti). Under cathodic polarization bacterial attachment was measured from changes in the ellipsometric angles. These were fitted to an effective medium model for a nonabsorbing bacterial film with an effective refractive index (nf) of 1.38 and a thickness (df) of 160 ± 10 nm. From the optical measurements a surface coverage of 17% was estimated, in agreement with direct microscopic observations. The influence of bacteria on the formation of oxide films was monitored by ellipsometry following the film growth in situ. A strong inhibition of metal oxide film formation was observed, which was assigned to the decrease in oxygen concentration due to the presence of bacteria. It is shown that the irreversible adhesion of bacteria to the surface can be monitored ellipsometrically. Electrophoretic mobility is proposed as one of the factors determining bacterial attachment. The high sensitivity of ellipsometry and its usefulness for the determination of growth of interfacial bacterial films is demonstrated. PMID:9758786

  14. Theoretical optical properties of composite metal NiO films

    NASA Astrophysics Data System (ADS)

    Ferreira, F. F.; Fantini, M. C. A.

    2003-10-01

    This paper reports theoretical optical properties of composite metal (Cu, Ag, Au, Ni, Pd and Pt) nickel oxide thin films, aiming to create a new electrochromic material. Selective absorption was verified only in composites with metals belonging to the IB column of the periodic table. In particular, emphasis was given to the spectral transmission, reflection and absorption, between 0.4 and 2.5 µm, of Au-NiO composite thin films, that showed the narrowest absorption band in the visible spectrum. Au-CoO films presented similar results. The calculations were based on the Maxwell-Garnett effective medium theory, with Au fill factors, f, varying from 0.0 to 0.2. The Au configurations were modelled to be isolated single spheres (ISS), isolated double spheres, single linear chain (SLC), double linear chain and fcc clusters (FCCs). Independent of the aggregate state, the increase in the fill factor enhances the selective absorption and broadens the absorption band of the films. Films with different thicknesses (0.1-0.3 µm), but with the same amount of Au particles per unit area and aggregate state, showed distinct interference patterns in the transmission and reflection spectra. The absorption spectra were almost insensitive to thickness, being very dependent on the gold content and configuration. The tailoring of the optical properties in the visible region of the Au-NiO films was achieved by controlling the Au configuration. A combination of ISS (25%), SLC (25%) and FCC (50%) was also simulated.

  15. Biomolecule-based antibacterial coating on a stainless steel surface: multilayer film build-up optimization and stability study

    Microsoft Academic Search

    C. Vreuls; G. Zocchi; H. Vandegaart; E. Faure; C. Detrembleur; Anne-Sophie Duwez; J. Martial; C. Van De Weerdt

    2012-01-01

    The goal of this paper was to establish the durability profile of antibacterial multilayer thin films under storage and usage conditions. Thin films were built on stainless steel (SS) by means of a layer-by-layer process alternating a negatively charged polyelectrolyte, polyacrylic acid, with a cationic antibacterial peptide, nisin. SS coupons coated with the antibacterial film were challenged under environmental and

  16. Preparation of superhydrophobic boehmite and anatase nanocomposite coating films

    SciTech Connect

    Hsiang, H.-I [Particulate Materials Research Center, Department of Resources Engineering, National Cheng Kung University, Tainan, Taiwan (China)]. E-mail: hsingi@mail.ncku.edu.tw; Liang, M.-T. [Particulate Materials Research Center, Department of Resources Engineering, National Cheng Kung University, Tainan, Taiwan (China); Department of Chemical Engineering, I-Shou University, Kaoshiung, Taiwan (China); Huang, H.-C. [Particulate Materials Research Center, Department of Resources Engineering, National Cheng Kung University, Tainan, Taiwan (China); Yen, F.-S. [Particulate Materials Research Center, Department of Resources Engineering, National Cheng Kung University, Tainan, Taiwan (China)

    2007-03-22

    Developing a surface with water-repelling and self-cleaning ability has attracted much interest in nano-technology. We prepared superhydrophobic films in this study using a mixture of small anatase particles and large boehmite particles. Additionally, a N{sub 2} automated adsorption apparatus, atomic force microscopy and contact angle meter were employed to examine the effects of the added boehmite and anatase to the boehmite ratio on the roughness, micropore ratio and contact angle of the hydrophobic films. As boehmite addition increased from 0 to 8 wt.%, the average roughness increased up to 30 nm, which resulted in the water contact angles increasing from 105{sup o} to 155{sup o}. The hardness of the films increased from 6B to 2H. The addition of a proper amount of small anatase particles into the large boehmite particles could lead to increasing the micropore ratio in the films, which would enhance the contact angle.

  17. Optimizing vanadium pentoxide thin films and multilayers from dip-coated nanofluid precursors.

    PubMed

    Glynn, Colm; Creedon, Donal; Geaney, Hugh; O'Connell, John; Holmes, Justin D; O'Dwyer, Colm

    2014-02-12

    Using an alkoxide-based precursor, a strategy for producing highly uniform thin films and multilayers of V2O5 is demonstrated using dip coating. Defect-free and smooth films of V2O5 on different surfaces can be deposited from liquid precursors. We show how pinholes are formed due to heterogeneous nucleation during hydrolysis as the precursor forms a nanofluid. Using knowledge of instability formation often found in composite nanofluid films and the influence of cluster formation on the stability of these films, we show how polymer-precursor mixtures provide optimum uniformity and very low surface roughness in amorphous V2O5 and also orthorhombic V2O5 after crystallization by heating. Pinhole and roughness instability formation during the liquid stage of the nanofluid on gold and ITO substrates is suppressed giving a uniform coating. Practically, understanding evolution pathways that involve dewetting processes, nucleation, decomposition, or hydrolysis in complex nanofluids provides a route for improved uniformity of thin films. The method could be extended to improve the consistency in sequential or iterative multilayer deposits of a range of liquid precursors for functional materials and coatings. PMID:24432710

  18. A micro force sensor based on a single ZnO belt coated with chromium film.

    PubMed

    Ren, Xiaoyan; Yang, Xing; Zhou, Zhaoying; Li, Jinming; Liu, Jing

    2010-11-01

    A micro force sensor was fabricated using a single ZnO belt coated with ultra thin Cr film. As a result of the piezoresistive effect of the ultra thin (in nano-scale) Cr film, the bending of the belt led to the change in the resistance of ultra thin Cr film. Based on the mechanics of the materials, the relationship between the deformation and the force was calculated, and a linear relationship between the bending force and the resistance of Cr thin film was deduced at small bending regions. Dielectrophoresis, focused ion beam (FIB) and sputtering were used in the process of the micro force sensor. The experimental results show that the resistance of Cr film is sensitive to the bending force and demonstrate the potential for developing a new class of stable and sensitive nano-sized structures for force sensing. PMID:21137908

  19. Studies on VOx thin films deposited over Si3N4 coated Si substrates

    NASA Astrophysics Data System (ADS)

    Raj, P. Deepak; Gupta, Sudha; Sridharan, M.

    2015-06-01

    Vanadium oxide (VOx) thin films were deposited on to the silicon nitride (Si3N4) coated silicon (Si) substrate using reactive direct current magnetron sputtering at different substrate temperatures (Ts). The deposited films were characterized for their structural, morphological, optical and electrical properties. The average grain size of the deposited films was in the range of 95 to 178 nm and the strain varied from 0.071 to 0.054 %. The optical bandgap values of the films were evaluated using UV-Vis spectroscopy and lies in the range of 2.46 to 3.88 eV. The temperature coefficient of resistance (TCR) for the film deposited at 125 °C was -1.23%/°C with the sheet resistivity of 2.7 ?.cm.

  20. Oxygen Plasma Modification of Poss-Coated Kapton(Registered TradeMark) HN Films

    NASA Technical Reports Server (NTRS)

    Wohl, C. J.; Belcher, M. A.; Ghose, S.; Connell, J. W.

    2008-01-01

    The surface energy of a material depends on both surface composition and topographic features. In an effort to modify the surface topography of Kapton(Registered TradeMark) HN film, organic solutions of a polyhedral oligomeric silsesquioxane, octakis(dimethylsilyloxy)silsesquioxane (POSS), were spray-coated onto the Kapton(Registered TradeMark) HN surface. Prior to POSS application, the Kapton(Registered TradeMark) HN film was activated by exposure to radio frequency (RF)-generated oxygen plasma. After POSS deposition and solvent evaporation, the films were exposed to various durations of RF-generated oxygen plasma to create a topographically rich surface. The modified films were characterized using optical microscopy, attenuated total reflection infrared (ATR-IR) spectroscopy, and high-resolution scanning electron microscopy (HRSEM). The physical properties of the modified films will be presented.