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Sample records for anticorrosion coatings

  1. Anticorrosive coatings: a review

    DEFF Research Database (Denmark)

    Sørensen, Per Aggerholm; Kiil, Søren; Dam-Johansen, Kim;

    2009-01-01

    The main objective of this review is to describe some of the important topics related to the use of marine and protective coatings for anticorrosive purposes. In this context, "protective" refers to coatings for containers, offshore constructions, wind turbines, storage tanks, bridges, rail cars......, and petrochemical plants while "marine" refers to coatings for ballast tanks, cargo holds and cargo tanks, decks, and engine rooms on ships. The review aims at providing a thorough picture of state-of-the-art in anticorrosive coatings systems. International and national legislation aiming at reducing...... the emission of volatile organic compounds (VOCs) have caused significant changes in the anticorrosive coating industry. The requirement for new VOC-compliant coating technologies means that coating manufacturers can no longer rely on the extensive track record of their time-served products to...

  2. Anti-Corrosion Coating

    Science.gov (United States)

    1986-01-01

    SuperSpan RM 8000 is an anti-corrosion coating which effectively counteracts acid degradation, abrasive wear, and cracking in power industry facilities. It was developed by RM Industrial Products Company, Inc. with NERAC assistance. It had previously been necessary to shut down plants to repair or replace corroded duct-work in coal burning utilities. NASA-developed technology was especially useful in areas relating to thermoconductivity of carbon steel and the bonding characteristics of polymers. The product has sold well.

  3. Self-Healing anticorrosive coatings

    DEFF Research Database (Denmark)

    Nesterova, Tatyana

    %. The number is lower than anticipated and needs to be confirmed. Finally, a 3-D model, based on Monte-Carlo simulations, has been developed for prediction of healing efficiency of a microcapsule-based anticorrosive coating. Two kinds of cracks were considered: cracks accommodated within the bulk coating......Self-healing anticorrosive coatings are multi-component so-called smart materials, which have been proposed as a way to long-lasting corrosion protection of steel structures. The presently most promising technology route is based on microcapsules, filled with active healing agents, and has been...... to capillary forces. The healing agents then start to react, form a polymer network, and =glue‘ the crack. The approach has been applied to development of an epoxy-based self-healing anticorrosive coating for above water heavy duty corrosion protection. Emphasis has been on investigation of practical issues...

  4. Anticorrosion diffusion coatings

    International Nuclear Information System (INIS)

    The effect of chemical- and heat treatment on corrosion resistance of steels in aqueous solutions of acids, salts and alkalies has been investigated to find a possibility of replacing stainless steel by carbon or low-alloyed steels with diffusion coatings. Data on corrosion resistance of steels with diffusion coatings such as Cr, Cr-Si, Cr-Ti, Cr-Al, Zr-Al, V-Al are presented. The mechanism of fracture of steels with coatings prepared under optimum conditions is studied

  5. Qualification of anticorrosive coatings in nuclear vessels

    International Nuclear Information System (INIS)

    Test qualifications of the behavior of anticorrosive coating systems used in nuclear vessels in service and under the accident conditions of radiation decontamination, steam chemical resistance, thermal conductivity, weathering accelerated aging are presented and discussed. (author)

  6. Organic/inorganic hybrid coatings for anticorrosion

    Science.gov (United States)

    He, Zhouying

    Compared to organic coatings, organic-inorganic hybrid coatings can potentially improve the anticorrosion performance. The organic phase provides the excellent mechaincal and barrier properties while the inorganic phase acts as an adhesion promoter and corrosion inhibitor. Despite that many studies on alkoxylsilane-based hybrid coatings have been developed and studied, their weatherability and anticorrosion performance has been rarely evaluated. On the other hand, organic-inorganic hybrid coatings based on mixed sol-gel precursors have received much less attention compared to alkoxylsilane-based hybrid coatings. In the first part, polyurethane hybrid coatings with a unique hybrid crosslinked structure as an improved unicoat were successfully prepared. The effect of polyesters on physical properties of the hybrid coatings was studied. Polyurethane coatings derived from cycloaliphatic polyester show comparable properties than those derived from the commercially viable aromatic polyester. Introducing the polysiloxane part into the polyurethane coatings enhanced the crosslinking density, Tg, mechanical properties, and general coating properties. The increased adhesion between the hybrid coating and the substrate make the hybrid coating a good candidate for anticorrosion application, which is shown by electrochemical impedance spectroscopy (EIS). The degradation mechanism of the polyurethane/polysiloxane hybrid coatings under various weathering conditions was shown to be the scission of the urethane and ester groups in the organic phase along with reorganizing and rearranging of the inorganic phase. The anticorrosion performance of the cycloaliphatic hybrid was much better than that of aromatic based hybrid under outdoor weathering based on visual observation and EIS analysis. Acid undercutting is an issue for TEOS based hybrid coating. In the second part, design of experiments (DOEs) was used to statistically investigate on the effect of sol-gel precursors. The

  7. Radiation resistance of anticorrosion coatings

    International Nuclear Information System (INIS)

    Experimental results are reported of a study of high-energy radiation and its effects on properties and corrosive behaviour of metals, on plastics, paints, and other coatings. The irradiation tests have been made with various paint compounds on the basis of epoxide resins, polyurethane resins, acryl/styrol dispersions, and with ethyl silicate or alkali silicate zinc dust primers. The coatings have been applied to accelerator component parts and to plate specimens (aluminium, steel) and have been irradiated with energies between 104 and 107 Gy. Very good results have been found for the polyurethane compound and the acryl/styrol dispersion coatings. (orig.)

  8. Anticorrosion properties of polyaniline-coated pigments in organic coatings

    Czech Academy of Sciences Publication Activity Database

    Kalendová, A.; Sapurina, I.; Stejskal, Jaroslav; Veselý, D.

    2008-01-01

    Roč. 50, č. 12 (2008), s. 3549-3560. ISSN 0010-938X R&D Projects: GA MŠk ME 847 Institutional research plan: CEZ:AV0Z40500505 Keywords : anticorrosion pigment * polyaniline * coating Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.293, year: 2008

  9. Anticorrosion properties of polyaniline-coated pigments in organic coatings

    International Nuclear Information System (INIS)

    Four pigments of various morphology - specularite, α-Fe2O3; goethite, α-FeO(OH); talc, (Mg3(OH)2(Si4O10); and graphite, C - without and with polyaniline phosphate coating, were tested for the anticorrosion performance in coatings produced by epoxy binders on iron plates. The corrosion tests were carried out in a condenser chamber with continuous water condensation or humidity with sulfur dioxide, and in a salt mist cabinet. Polyaniline coating of pigments in all cases improved the anticorrosion properties. Graphite coated with polyaniline performed the best among eight systems under investigation. The role of graphite and polyaniline conductivity in the electron transfers associated with corrosion of iron has been proposed

  10. Actual problems of ultrasonic testing of surfacing anticorrosion coatings

    International Nuclear Information System (INIS)

    Reasons for a change of equivalent sizes of NPP equipmet surfacing anticorrosion coating discontinuities are investigated. Evaluation of the limiting level of the coating ultrasonic testing (UST) sensitivity is conducted. Results of complex experimental efforts using UST of the NPP surfacing components which agree with practice are presented

  11. Pulsed laser deposited praseodymium zinc molybdate coating for anticorrosion applications

    International Nuclear Information System (INIS)

    The praseodymium zinc molybdate nanopigment prepared by sol-gel was coated over SS steel 301 at 200℃ by Pulsed laser deposition for anticorrosion application. The prepared compound is a better alternative to lead, cadmium and chromium pigments, in which Cr6+ is carcinogenic, responsible for human diseases. The combination of a four-beam PLD evaporator with a suitable movement of the substrates results in a high-rate film growth on large surfaces. The nano pigment coated surface was investigated using X-ray diffraction analysis shows the combined phases of praseodymium zinc molybdate nano particles along with molybdate and praseodymium oxide, confirmed. Scanning electron microscopy shows the uniform coating without cracks and porosity on the surface. (author)

  12. Complex anticorrosion coating for ZK30 magnesium alloy

    International Nuclear Information System (INIS)

    This work aims at developing a new complex anticorrosion protection system for ZK30 magnesium alloy. This protective coating is based on an anodic oxide layer loaded with corrosion inhibitors in its pores, which is then sealed with a sol-gel hybrid polymer. The porous oxide layer is produced by spark anodizing. The sol-gel film shows good adhesion to the oxide layer as it penetrates through the pores of the anodized layer forming an additional transient oxide-sol-gel interlayer. The thickness of this complex protective coating is about 3.7-7.0 μm. A blank oxide-sol-gel coating system or one doped with Ce3+ ions proved to be effective corrosion protection for the magnesium alloy preventing corrosion attack after exposure for a relatively long duration in an aggressive NaCl solution. The structure and the thickness of the anodized layer and the sol-gel film were characterized by scanning electron microscopy (SEM). The corrosion behaviour of the ZK30 substrates pre-treated with the complex coating was tested by electrochemical impedance spectroscopy (EIS), scanning vibrating electrode technique (SVET), and scanning ion-selective electrode techniques (SIET).

  13. Actual problems of ultrasonic control of welded anticorrosion coatings (ch. 1)

    International Nuclear Information System (INIS)

    Results of investigations into heat treatment effect on the size of discontinuities revealed under ultrasonic control (USC) of welded anticorrosion coatings are presented. Comparison of dimensions of equivalent area of allowable and non-allowable reflector-discantinuities (defectiveness standards) in the alloying zone of melted anticorrosion coatings and bimetal sheet, applied in NPP equipment, is given. It is shown that USC on the side of basic metal monifest almost by an order more defects than USC on the side of melting surface

  14. Applying of non-toxic oxide alloys and hybrid polianiline compounds as anticorrosive pigments in organic epoxy coatings

    Science.gov (United States)

    Szymański, W.; Halama, A.; Madaliński, J.

    2016-02-01

    The objective of this work was to study inorganic oxide pigments as well as polyaniline heptamolybdes anticorrosive efficiency in epoxy coating. Antycorrosion resistance of modified coatings was examined by accelerated corrosion test in comparison to coatings of the suitable commercial epoxy paint. The carried out investigations shoved much bigrs anticorrosion performance of coatings modified with elaborated, new pigments.

  15. Improving anti-corrosion property of thermal barrier coatings by intense pulsed ion beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Yan, S., E-mail: syan@pku.edu.cn [State Key Laboratory of Nuclear Physics and Technology, Institute of Heavy Ion Physics, Peking University, Beijing 100871 (China); Shang, Y.J., E-mail: shangyijun@pku.edu.cn [State Key Laboratory of Nuclear Physics and Technology, Institute of Heavy Ion Physics, Peking University, Beijing 100871 (China); Xu, X.F., E-mail: reandy123@126.com [State Key Laboratory of Nuclear Physics and Technology, Institute of Heavy Ion Physics, Peking University, Beijing 100871 (China); Yi, X., E-mail: xyle@buaa.edu.com [Department of Applied Physics, School of Science, Beihang University, Beijing 100083 (China); Le, X.Y., E-mail: xyle@buaa.edu.cn [Department of Applied Physics, School of Science, Beihang University, Beijing 100083 (China)

    2012-02-01

    Anticorrosion behavior is an important factor for the reliability and durability of thermal barrier coatings (TBCs). Intense pulsed ion beam (ion species: 70% H{sup +} + 30% C{sup +}; current density: 150 A/cm{sup 2} and 250 A/cm{sup 2}; accelerate voltage: 300 kV; pulse duration: 65 ns) irradiation were used to improve the anticorrosion behavior of the Y{sub 2}O{sub 3}-stabilized ZrO{sub 2} (YSZ) /NiCoCrAlY thermal barrier coating. The anticorrosion property of the TBCs was evaluated with polarization curves method. A quite good result was obtained. Further analysis show that IPIB irradiation can seal the pores in YSZ layer, and block the penetration channels of corrosive fluid, therefore, improves the anticorrosion behavior.

  16. Improving anti-corrosion property of thermal barrier coatings by intense pulsed ion beam irradiation

    Science.gov (United States)

    Yan, S.; Shang, Y. J.; Xu, X. F.; Yi, X.; Le, X. Y.

    2012-02-01

    Anticorrosion behavior is an important factor for the reliability and durability of thermal barrier coatings (TBCs). Intense pulsed ion beam (ion species: 70% H + + 30% C +; current density: 150 A/cm 2 and 250 A/cm 2; accelerate voltage: 300 kV; pulse duration: 65 ns) irradiation were used to improve the anticorrosion behavior of the Y 2O 3-stabilized ZrO 2 (YSZ) /NiCoCrAlY thermal barrier coating. The anticorrosion property of the TBCs was evaluated with polarization curves method. A quite good result was obtained. Further analysis show that IPIB irradiation can seal the pores in YSZ layer, and block the penetration channels of corrosive fluid, therefore, improves the anticorrosion behavior.

  17. Improving anti-corrosion property of thermal barrier coatings by intense pulsed ion beam irradiation

    International Nuclear Information System (INIS)

    Anticorrosion behavior is an important factor for the reliability and durability of thermal barrier coatings (TBCs). Intense pulsed ion beam (ion species: 70% H+ + 30% C+; current density: 150 A/cm2 and 250 A/cm2; accelerate voltage: 300 kV; pulse duration: 65 ns) irradiation were used to improve the anticorrosion behavior of the Y2O3-stabilized ZrO2 (YSZ) /NiCoCrAlY thermal barrier coating. The anticorrosion property of the TBCs was evaluated with polarization curves method. A quite good result was obtained. Further analysis show that IPIB irradiation can seal the pores in YSZ layer, and block the penetration channels of corrosive fluid, therefore, improves the anticorrosion behavior.

  18. Development of Exterior Anti-corrosion Coating Production Line for Large Diameter Hot Bent Pipes

    Institute of Scientific and Technical Information of China (English)

    JiaoRuyi; ZhangYing

    2004-01-01

    The epoxy powder exterior anti-corrosion coating production line for bent pipes with a single (double) course production is a technologically advanced bent pipe anti-corrosion method with cost efficiency, environment friendliness and stable coating quality. The quality of the coating on the bent pipe fully meets the requirements of the current national and industrial standards. The application of the technology has filled the gap in the bent pipe anti-corrosion coating area of China, and leads the world technologically. With this technology the coating quality of the bent pipe has greatly improved, resulting in significant social and economic benefits. With the use of the technology in various large scale pipeline projects such as the “West to East Gas Pipeline Project”, it will exhibite a greater potential in the future pipeline projects with a broad application prospect.

  19. Research on the Anticorrosion Coating Under the Paved Layer for Highway Steel Box Bridge Deck

    Institute of Scientific and Technical Information of China (English)

    SHEN Cheng-jin; MING Tu-zhang; HU Guang-wei; OU Xue-mei; GEN Ou

    2006-01-01

    The corrosion of the anticorrosion coating and the defects of the asphalt concrete paved layer have been investigated on long-span steel box bridge decks. The anticorrosion coating lies in the middle of two entirely different materials: a highway steel box bridge deck and a paved layer, which is used as anticorrosion and waterproof coating for the steel bridge deck. For our study, electrochemical corrosion and pull strength experiments have been selected for the investigation of the corrosion properties of inorganic zinc rich coating, epoxy zinc rich coating and arc sprayed zinc coating. The adhesive strength between the coatings and the panel, and the effect of the coating corrosion on the shear properties of the paved layers including cast asphalt, thermal asphalt mortar, epoxy asphalt and modified asphalt concrete have been investigated. The results show that the adhesive strength between the coatings and the bridge panel is controlled by the method of pre-processing rust removal. Coating by sandblasting has stronger adhesive strength than coating by shot peening. The results also reveal that shear strength of the paved layer is affected by the corrosion product of zinc coating. The arc sprayed zinc coating has stronger shear strength than zinc rich coatings.

  20. Graphene as an anti-corrosion coating layer.

    Science.gov (United States)

    Kyhl, Line; Nielsen, Sune Fuglsang; Čabo, Antonija Grubišić; Cassidy, Andrew; Miwa, Jill A; Hornekær, Liv

    2015-01-01

    Graphene, a single layer of carbon atoms arranged in an aromatic hexagonal lattice, has recently drawn attention as a potential coating material due to its impermeability, thermodynamic stability, transparency and flexibility. Here, the effectiveness of a model system, a graphene covered Pt(100) surface, for studying the anti-corrosion properties of graphene, has been evaluated. Chemical vapour deposition techniques were used to cover the single crystal surface with a complete layer of high-quality graphene and the surface was characterised after exposure to corrosive environments with scanning tunnelling microscopy (STM) and Raman spectroscopy. Graphene covered Pt samples were exposed to: (i) ambient atmosphere for 6 months at room temperature and 60 °C for 75 min, (ii) Milli-Q water for 14 hours at room temperature and 60 °C for 75 min, and (iii) saltwater (0.513 M NaCl) for 75 min at room temperature and 60 °C. STM provides atomic resolution images, which show that the graphene layer and the underlying surface reconstruction on the Pt(100) surface remain intact over the majority of the surface under all conditions, except exposure to saltwater when the sample is kept at 60 °C. Raman spectroscopy shows a broadening of all graphene related peaks due to hybridisation between the surface Pt d-orbitals and the graphene π-bands. This hybridisation also survives exposure to all environments except saltwater on the hot surface, with the latter leading to peaks more representative of a quasi free-standing graphene layer. A mechanism explaining the corrosive effect of hot saltwater is suggested. Based on these experiments, graphene is proposed to offer protection against corrosion in all tested environments, except saltwater on a hot surface, and Raman spectroscopy is proposed as a useful method for indirectly assessing the chemical state of the Pt surface. PMID:25915827

  1. Anticorrosion characteristics of a Zn-primer coating in a ballast tank under various chloride concentrations

    International Nuclear Information System (INIS)

    At an open-circuit potential, the anodic polarization curves had very similar values, and no significant differences were observed among the conditions. In the cathodic polarization curves, total residual chloride (TRC) reacted with the Zn-primer coating and created a film that had anticorrosion properties. Therefore, the anticorrosion property improved. With an increase in applied potential in the potentiostatic experiment, the observed surface corrosion occurred due to the dissolution reaction. From Tafel analysis, the corrosion current density had the highest value in natural seawater and the lowest value in the 2 ppm solution. Generally, metals corrode faster with increasing TRC concentration, but with the formation of Zn(OH)2, which has anticorrosion properties, the corrosion resistance of a Zn-primer-coated specimen in seawater can be improved.

  2. Anticorrosion properties of tin oxide coatings for carbonaceous bipolar plates of proton exchange membrane fuel cells

    Science.gov (United States)

    Kinumoto, Taro; Nagano, Keita; Yamamoto, Yuji; Tsumura, Tomoki; Toyoda, Masahiro

    2014-03-01

    An anticorrosive surface treatment of a carbonaceous bipolar plate used in proton exchange membrane fuel cells (PEMFCs) was demonstrated by addition of a tin oxide surface coating by liquid phase deposition (LPD), and its effectiveness toward corrosion prevention was determined. The tin oxide coating was deposited by immersion in tin fluoride and boric acid solutions, without any observable decrease in the bipolar plate electrical conductivity. Anticorrosion properties of a flat carbonaceous bipolar plate were investigated in an aqueous HClO4 electrolyte solution (10 μmol dm-3) at 80 °C. CO2 release due to corrosion was significant for the bare specimen above 1.3 V, whereas no CO2 release was noted for the tin-oxide-coated specimen, even approaching 1.5 V. Moreover, minimal changes in contact angle against a water droplet before and after treatment indicated suppressed corrosion of the surface-coated specimen. Anticorrosion properties were also confirmed for a model bipolar plate having four gas flow channels. The tin oxide layer remained on the channel surfaces (inner walls, corners and intersections) after durability tests. Based on these results, tin-oxide-based surface coatings fabricated by LPD show promise as an anticorrosion technique for carbonaceous bipolar plates for PEMFCs.

  3. Superamphiphobic and Electroactive Nanocomposite toward Self-Cleaning, Antiwear, and Anticorrosion Coatings.

    Science.gov (United States)

    Yuan, Ruixia; Wu, Shiqi; Yu, Peng; Wang, Baohui; Mu, Liwen; Zhang, Xiguang; Zhu, Yixing; Wang, Bing; Wang, Huaiyuan; Zhu, Jiahua

    2016-05-18

    Multifunctional coatings are in urgent demand in emerging fields. In this work, nanocomposite coatings with extraordinary self-cleaning, antiwear, and anticorrosion properties were prepared on aluminum substrate by a facile spraying technique. Core-shell structured polyaniline/functionalized carbon nanotubes (PANI/fCNTs) composite and nanosized silica were synergistically integrated into ethylene tetrafluoroethylene (ETFE) matrix to construct lotus-leaf-like structures, and 1H,1H,2H,2H- perfluorooctyltriethoxysilane (POTS) was used to decrease the surface energy. The composite coating with 6 wt % PANI/fCNTs possesses superamphiphobic property, with contact angles of 167°, 163°, and 159° toward water, glycerol, and ethylene glycol, respectively. This coating demonstrates stable nonwetting performance over a wide temperature range (cleaning ability to prevent contamination by sludge, concentrated H2SO4, and ethylene glycol. Superamphiphobic surface property could be maintained even after 45 000 times abrasion or bending test for 30 times. The coating displayed strong adhesive ability (grade 1 according to the GB/T9286) on the etched aluminum plate. The superamphiphobic surface could be retained after immersion in 1 mol/L HCl and 3.5 wt % NaCl solutions for 60 and 90 d, respectively. It should be noted that this coating reveals significantly improved anticorrosion performance as compared to the bare ETFE coating and ETFE composite coating without PANI/fCNTs. Such coatings with integrated functionalities offer promising self-cleaning and anticorrosion applications under erosive/abrasive environment. PMID:27136103

  4. Fabrication and Assessment of Crumb-Rubber-Modified Coatings with Anticorrosive Properties

    OpenAIRE

    Nasser Al-Aqeeli

    2015-01-01

    Scrap tires continue to be a major source of waste due to the lack of valuable and effective disposal routes. A viable solution to this problem is to recycle crumb rubber (CR)—a granulated material derived from scrap tires—and use it to develop other valuable products. Herein we report the fabrication and characterization of CR-modified coatings with anticorrosive properties on metal substrates. By varying the particle size and concentration of CR, we have determined the coating composition ...

  5. A study of the anti-corrosive coating for radioactive waste water storage tanks

    International Nuclear Information System (INIS)

    This paper describes briefly the testing results and method of a kind of anti-corrosive coating, which consisted of bitumen and other chemicals. The coating was tested in several kinds of simulated waste water under γ-irradiation. Some coupons of the coating were γ-irradiated in the air also. The tested coating has been applied to the Low-level radioactive waste water storage tanks, which are made of carbon steel, for more than 15 years. Those storage tanks are being used well now

  6. Anticorrosive coatings for storage tanks; Revestimentos anticorrosivos para tanques de armazenamento de petroquimicos

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Jeferson de [Coordenacao dos Programas de Pos-graduacao em Engenharia (COPPE/UFRJ), RJ (Brazil). Lab. de Ensaios Nao Destrutivos, Corrosao e Soldagem; Silva, Cosmelina G. da; Mattos, Oscar R. [Coordenacao dos Programas de Pos-graduacao em Engenharia (COPPE/UFRJ), RJ (Brazil). Programa de Engenharia Metalurgica e de Materiais; Margarit-Mattos, Isabel C.P. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Escola de Quimica. Dept. de Processos Inorganicos; Solymossy, Victor; Quintela, Joaquim P. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2008-07-01

    The anticorrosive performance of commercial coatings that can be employed inside petrochemical storing reservoirs was evaluated. The aim is to select products able to extend the time between maintenance. Some of the products tested are composites and formulas with novolac resins. The tests were: cathodic delamination and total immersion in distilled water at 40 deg C, formation water at 80 deg C, NaOH 20%, H{sub 2}SO{sub 4} 20%, MIBK, ethanol and naphtha. The performance evaluation took into account the presence of corrosion, blistering, adhesion loss and electrochemical properties. Based on the results, considerations are made about the adequacy of tests and procedures for the new generations of organic anticorrosive coatings. (author)

  7. Effect of Nano Al Pigment on the Anticorrosive Performance of Waterborne Epoxy Coatings

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This paper presents the results regarding the effect of nano aluminum powder pigment concentration on the protective properties of waterborne epoxy films in 3.5 wt pct NaCl solution. The anticorrosive performance of the coatings with 0.5, 1, and 3 wt pct pigments and none pigment were investigated using electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and Raman spectroscopy techniques.The results show that adding appropriate amount of nano-aluminium powder pigment can enhance the barrier properties of the epoxy coating, which is attributed to the surface effect of nanoparticles and the compatibility of the pigment with the waterborne epoxy coatings.

  8. Study of Polyaniline/Vermiculie/Tert-fluoro Emulsion Composites Anticorrosion Coatings

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    1 Results Polyaniline (PANI) is one of the most promising materials for commercial applications.It can be applied to electronic devices and products such as light-emitting diodes,organic FETs,EMI shielding,secondary batteries,etc.Composites of polyaniline with other polymers or inorganic materials can provide new synergistic properties that cannot be attained from individual materials.Vermiculite (VMT) is a chain-layer magnesium-aluminum silicate mineral.We prepared composite anticorrosion coatings of p...

  9. An intelligent anticorrosion coating based on pH-responsive supramolecular nanocontainers

    International Nuclear Information System (INIS)

    The hollow mesoporous silica nanoparticles (HMSNs), which have been used as the nanocontainers for the corrosion inhibitor, benzotriazole, were fabricated using the hard-template method. Alkaline-responsive HMSNs based on cucurbit[6]uril (CB[6])/bisammonium supramolecular complex and acid-responsive HMSNs based on α-cyclodextrin (α-CD)/aniline supramolecular complex, which operate in water, have been achieved and characterized by solid-state NMR, thermogravimetry analysis, scanning electron microscopy, transmission electron microscopy and N2 adsorption-desorption analysis. The two elaborately designed nanocontainers show the pH-controlled encapsulation/release behaviors for benzotriazole molecules. Equal amounts of the alkaline- and acid-responsive nanocontainers were uniformly distributed in the hybrid zirconia-silica sol–gel coating and thus formed the intelligent anticorrosion coating. The self-healing property of AA2024 alloy coated with the intelligent anticorrosion coating is evaluated by electrochemical impedance spectroscopy (EIS). The sol–gel coating doped with the pH-responsive nanocontainers clearly demonstrates long-term corrosion protection performances when compared to the undoped sol–gel coating, which is attributed to the release of corrosion inhibitor from the nanocontainers after feeling the changes of environmental pH values near the corroded areas. (paper)

  10. Application of Ketone-Based Resins as Anticorrosive Coating

    OpenAIRE

    Esma Sezer; Nilgün Kızılcan; Kerim Çoban

    2011-01-01

    Effect of some newly synthesized modified ketonic resins on corrosion inhibition of stainless steel (SS) and copper (Cu) was investigated in acidic medium. Carboxyl, hydroxyl, and carbonyl functionalized resins have been coated on metal electrode as a thin film by dipping method. Corrosion characteristics of coating on SS (304 L) and Cu were investigated by polarization, open-circuit, and impedance measurement. These measurements performed at different time and the stability of polymeric coat...

  11. Self-healing Coatings for an Anti-corrosion barrier in Damaged Parts

    International Nuclear Information System (INIS)

    Polymer coatings are commonly applied to metal substrates to prevent corrosion in aggressive environments such as high humidity and under salt water. Once the polymer coating has been breached, for example due to cracking or scratches, it loses its effectiveness, and corrosion can rapidly propagate across the substrate. The self-healing system we will describe prevents corrosion by healing the damage through a healing reaction triggered by the actual damage event. This self-healing coating solution can be easily applied to most substrate materials, and our dual-capsule healing system provides a general approach to be compatible with most common polymer matrices. Specifically, we expect an excellent anti-corrosion property of the self-healing coatings in damaged parts coated on galvanized metal substrates.

  12. Electrochemical measurements of siloxane polymers for anticorrosion coatings

    International Nuclear Information System (INIS)

    Full text: We report on the ability of various coatings, prepared from model organofunctional silanes of form (C3H7)Si(CH3)n(OH)3.n, where n = 1,2 or 3, to provide a barrier to corrosion. These coatings have been characterised with electrochemical impedance spectroscopy (EIS) and X-ray Photoelectron Spectroscopy (XPS) measurements. Surface coatings from pH 2 and 4 aqueous solutions of these materials have been formed on the native oxide of aluminium, and studied with XPS at Flinders and EIS at LaTrobe. Our results show an interesting correlation between the number of active silanol species and the corrosion performance of the respective coating. Copyright (2005) Australian Institute of Physics

  13. Influence of substrate topography on cathodic delamination of anticorrosive coatings

    OpenAIRE

    Sørensen, Per Aggerholm; Kiil, Søren; Dam-Johansen, Kim; Weinall, C.E.

    2009-01-01

    The cathodic delamination of a commercial magnesium silicate and titanium dioxide pigmented epoxy coating on abrasive cleaned cold rolled steel has been investigated. The rate of delamination was found to depend on interfacial transport from the artificial defect to the delamination front and thereby the substrate topography, whereas the coating thickness had little influence. The presence of a significant potential gradient between the anode and the cathode and the dependency of the delamina...

  14. ANTICORROSION PROPERTIES OF ORGANIC COATINGS CONTAINING POLYPHENYLENEDIAMINE PHOSPHATE

    OpenAIRE

    Miroslav Kohl; Andréa Kalendová

    2015-01-01

    The present work was aimed at the synthesis of polyphenylenediamine, its description and determination of parameters whose knowledge is required for the formulation of organic coatings pigmented with this compound. Polyphenylenediamine phosphate was prepared by oxidation polymerization in acidic environment. Phosphoric acid was used as the doping acid. Based on the results, pigmented organic coatings containing polyphenylenediamine at volume concentrations of 0%, 0.5%, 1%, 3%; 5%, and 10% wer...

  15. Self-healing anticorrosive organic coating based on an encapsulated water reactive silyl ester: synthesis and proof of concept

    NARCIS (Netherlands)

    García, S.J.; Fischer, H.R.; White, P.A.; Mardel, J.; González-García, Y.; Mol, J.M.C.; Hughes, A.E.

    2011-01-01

    In this paper a self-healing anticorrosive organic coating based on an encapsulated water reactive organic agent is presented. A reactive silyl ester is proposed as a new organic reactive healing agent and its synthesis, performance, incorporation into an organic coating and evaluation of self-heali

  16. ANTICORROSION PROPERTIES OF ORGANIC COATINGS CONTAINING POLYPHENYLENEDIAMINE PHOSPHATE

    Directory of Open Access Journals (Sweden)

    Miroslav Kohl

    2015-11-01

    Full Text Available The present work was aimed at the synthesis of polyphenylenediamine, its description and determination of parameters whose knowledge is required for the formulation of organic coatings pigmented with this compound. Polyphenylenediamine phosphate was prepared by oxidation polymerization in acidic environment. Phosphoric acid was used as the doping acid. Based on the results, pigmented organic coatings containing polyphenylenediamine at volume concentrations of 0%, 0.5%, 1%, 3%; 5%, and 10% were formed. The effect of the conductive polymer on the organic coatings‘ corrosion properties was examined via accelerated corrosion tests. From the results of an accelerated corrosion test it follows that if added to an epoxy-ester coating, this pigment improves appreciably the coating‘s corrosion resistance, especially at low pigment volume concentrations.

  17. Influence of substrate topography on cathodic delamination of anticorrosive coatings

    DEFF Research Database (Denmark)

    Sørensen, Per Aggerholm; Kiil, Søren; Dam-Johansen, Kim; Weinall, C.E.

    The cathodic delamination of a commercial magnesium silicate and titanium dioxide pigmented epoxy coating on abrasive cleaned cold rolled steel has been investigated. The rate of delamination was found to depend on interfacial transport from the artificial defect to the delamination front and...

  18. Growth of graphene on cylindrical copper conductors as an anticorrosion coating: a microscopic study

    Science.gov (United States)

    Datta, A. J.; Gupta, B.; Shafiei, M.; Taylor, R.; Motta, N.

    2016-07-01

    We have successfully grown graphene film on the surface of cylindrical copper conductors by chemical vapour deposition. The quality and number of graphene layers have been investigated using Raman spectroscopy, Raman mapping and scanning electron microscopy, as a function of methane gas flow rate and of growth temperature. Transmission electron microscopy analysis has been performed to verify the number of graphene layers, confirming the results obtained by Raman spectroscopy. The results open up the possibility of using graphene as an anticorrosion coating for copper cables and earth grids.

  19. UV-curable nanocasting technique to prepare bioinspired superhydrophobic organic-inorganic composite anticorrosion coatings

    Directory of Open Access Journals (Sweden)

    K. C. Chang

    2015-02-01

    Full Text Available A UV-curing technique was used to develop advanced anticorrosive coatings made of a poly(methyl methacrylate (PMMA/silica composite (PSC with bioinspired Xanthosoma sagittifolium leaf-like superhydrophobic surfaces. First of all, a transparent soft template with negative patterns of xanthosoma sagittifolium leaf can be fabricated by thermally curing the polydimethylsiloxane (PDMS pre-polymer in molds at 60°C for 4 h, followed by detaching PDMS template from the surface of natural leaf. PSC coatings with biomimetic structures can be prepared by performing the UV-radiation process upon casting UV-curable precursor with photo-initiator onto cold-rolled steel (CRS electrode under PDMS template. Subsequently, UV-radiation process was carried out by using light source with light intensity of 100 mW/cm2 with exposing wavelength of 365 nm. Surface morphologies of the as-synthesized hydrophobic PMMA (HP and superhydrophobic PSC (SPSC coatings showed a large number of micro-scaled mastoids, each decorated with many nano-scaled wrinkles that were systematically investigated by using scanning electron microscopy (SEM. The contact angles of water droplets on the sample surfaces can be increased from ~81 and 103° on PMMA and PSC surfaces to ~148 and 163° on HP and SPSC surfaces, respectively. The SPSC coating was found to provide an advanced corrosion protection effect on CRS electrodes compared to that of neat PMMA, PSC, and HP coatings based on a series of electrochemical corrosion measurements in 3.5 wt% NaCl electrolyte. Enhanced corrosion protection of SPSC coatings on CRS electrodes can be illustrated by that the silica nanoparticles on the small papillary hills of the bioinspired structure of the surface further increased the surface roughness, making the surface exhibit superior superhydrophobic, and thus leading to much better anticorrosion performance.

  20. Preparation technology and anti-corrosion performances of black ceramic coatings formed by micro-arc oxidation on aluminum alloys

    Institute of Scientific and Technical Information of China (English)

    CHEN Ling; HAN Jing; YU Shengxue

    2006-01-01

    In order to prepare ornamental and anti-corrosive coating on aluminum alloys, preparation technology of black micro-arc ceramic coatings on Al alloys in silicate based electrolyte was studied.The influence of content of Na2WO4 and combination additive in solution on the performance of black ceramic coatings was studied; the anticorrosion performances of black ceramic coatings were evaluated through whole-immersion test and electrochemical method in 3.5% NaCl solution at different pH value; SEM and XRD were used to analyze the surface morphology and phase constitutes of the black ceramic coatings.Experimental results indicated that, without combination additives, with the increasing of Na2WO4 content in the electrolyte, ceramic coating became darker and thicker, but the color was not black; after adding combination additive, the coating turned to be black; the black ceramic coating was multi-hole form in surface.There was a small quantity of tungsten existing in the black ceramic coating beside α-Al2O3 phase and β-Al2O3 phase.And aluminum alloy with black ceramic coating exhibited excellent anti-corrosion property in acid, basic and neutral 3.5% NaCl solution.

  1. Fabrication and Assessment of Crumb-Rubber-Modified Coatings with Anticorrosive Properties

    Directory of Open Access Journals (Sweden)

    Nasser Al-Aqeeli

    2015-01-01

    Full Text Available Scrap tires continue to be a major source of waste due to the lack of valuable and effective disposal routes. A viable solution to this problem is to recycle crumb rubber (CR—a granulated material derived from scrap tires—and use it to develop other valuable products. Herein we report the fabrication and characterization of CR-modified coatings with anticorrosive properties on metal substrates. By varying the particle size and concentration of CR, we have determined the coating composition that offers the highest level of erosion protection. Images from a scanning electron microscope (SEM reveal that CR is homogenously dispersed in the coating, especially when fine particles are used. As the concentration of CR increases, the hardness of the coating decreases as a result of the elastic properties of CR. More importantly, the erosion rate of the coating decreases due to increased ductility. Following Potentiodynamic tests, the utilization of these coatings proved to be beneficial as they showed good protection against aqueous corrosion when tested in 0.5 M NaCl solution. Our newly developed coatings offer an incentive to recycling CR and open up a safe and sustainable route to the disposal of scrap tires.

  2. Effect of pretreating technologies on the adhesive strength and anticorrosion property of Zn coated NdFeB specimens

    Science.gov (United States)

    Zhang, Pengjie; Xu, Guangqing; Liu, Jiaqin; Yi, Xiaofei; Wu, Yucheng; Chen, JingWu

    2016-02-01

    Zinc coated NdFeB specimens were prepared with different pretreating technologies, such as polishing, pickling (50 s), sandblasting and combined technology of sandblasting and pickling (5 s). Morphologies of the NdFeB substrates pretreated with different technologies were observed with a scanning electron microscope equipped with an energy dispersive spectrometer and an atomic force microscope. The tensile test was performed to measure the adhesive strength between Zn coating and NdFeB substrate. The self-corrosion behavior of the NdFeB specimen was characterized by potentiodynamic polarization curve. The anticorrosion properties of Zn coated NdFeB specimens were characterized by neutral salt spray tests. The pretreating technologies possess obvious impact on the adhesive strength and anticorrosion property of Zn coated NdFeB specimens. Combined pretreating technology of sandblasting and pickling (5 s) achieves the highest adhesive strength (25.56 MPa) and excellent anticorrosion property (average corrosion current density of 21 μA/cm2) in the four pretreating technologies. The impacting mechanisms of the pretreating technology on the adhesive strength and anticorrosion properties are deeply discussed.

  3. Electrochemical behavior and anticorrosion properties of modified polyaniline dispersed in polyvinylacetate coating on carbon steel

    International Nuclear Information System (INIS)

    Conducting polyaniline (Pani) was prepared in the presence of methane sulfonic acid (MeSA) as dopant by chemical oxidative polymerization. The Pani-MeSA polymer was characterized by FT-IR, UV-vis, X-ray diffraction (XRD) and impedance spectroscopy. The polymer was dispersed in polyvinylacetate and coated on carbon steel samples by a dipping method. The electrochemical behavior and anticorrosion properties of the coating on carbon steel in 3% NaCl were investigated using open-circuit potential (OCP) versus time of exposure, and electrochemical techniques including electrochemical impedance spectroscopy (EIS), potentiodynamic polarization and cyclic voltammetry (CV). During initial exposure, the OCP dropped about 0.35 V and the interfacial resistance increased several times, indicating a certain reduction of the polymer and oxidation of the steel surface. Later the OCP shifted to the noble direction and remained at a stable value during the exposure up to 60 days. The EIS monitoring also revealed the initial change and later stabilization of the coating. The stable high OCP and low coating impedance suggest that the conducting polymer maintains its oxidative state and provides corrosion protection for carbon steel throughout the investigated period. The polarization curves and CV show that the conducting polymer coating induces a passive-like behavior and greatly reduces the corrosion of carbon steel

  4. Determination of coating thickness, homogeneity and selective component leaching of sour service anti-corrosion coatings on mild steel by synchrotron infrared microspectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, K.J.; Apelblat, Y.; Theriault, Y.; Webb, M.A. [Alberta Synchrotron Inst., Edmonton, AB (Canada); Michaelian, K.H. [Natural Resources Canada, Devon, AB (Canada). CANMET Energy Technology Centre

    2004-07-01

    Mild steel with a corrosion protection coating made up of fatty imidazoline and fatty acid mixtures was subjected to a synchrotron radiation source and a bench-top Globar source to obtain an infrared microscope spectra of the protective coating. The synchrotron infrared microspectroscopy offered higher spatial resolution than the bench-top microscope. The spectra revealed that the anti-corrosion coatings were not homogeneous, with wide range in thicknesses and a 1 to 5 per cent error in each thickness measurement. The data was used to determine the effect on coating homogeneity resulting from changes in the coating times as well as the coating composition. The selective leaching of components from the anti-corrosion coatings was determined from an analysis of the infrared spectra obtained before and after corrosion testing in sour brine solutions.

  5. Long-Term Anti-Corrosion Performance of a Conducting Polymer-Based Coating System for Steels

    Science.gov (United States)

    Pan, Tongyan; Yu, Qifeng

    2016-06-01

    The long-term durability of a two-layer coating system was evaluated by two accelerated corrosion tests, i.e., the ASTM B117 Salt spray test and the ASTM D5894 Cyclic salt fog/UV exposure test, and a series of surface analyses. The coating system was developed for protecting structural steels from corrosion, including a functional primer made of intrinsically conducting polymer (ICP) and a protective topcoat. The standard pull-off test per ASTM D4541 was employed for characterizing the adhesion of the coating systems to substrate, aided by visual examination of the surface deterioration of the samples. The ICP-based systems demonstrated superior long-term anti-corrosion capacity when a polyurethane topcoat is used. The ICP-based primer made of a waterborne epoxy gave poorer anti-corrosion performance than the ICP-based primer made of regular non-waterborne epoxy, which can be attributed to the lower adhesion the waterborne epoxy demonstrated to the substrate surface. The zinc-rich control systems showed good anti-corrosion durability; however, they may produce excessive oxidative products of zinc to cause coating delamination. Based on the test results, the two-layer coating system consisting of an ICP-based primer and a polyurethane topcoat outperforms the conventional zinc-rich coating systems for corrosion protection of steels.

  6. Deposition of anti-corrosion coatings by atmospheric pressure plasma jet

    International Nuclear Information System (INIS)

    An atmospheric-pressure, non-equilibrium plasma jet is currently under investigation at Chalk River Laboratories for the application of anti-corrosion coatings. This device produces concentrations of chemically-active species, similar to those observed in low-pressure plasma deposition systems, with the advantage of operating in an ambient pressure atmosphere. This paper describes measurements of the properties of a bench-scale plasma jet operating in etch and deposition mode. The jet effluent was characterized by various methods, including optical emission spectroscopy. Films deposited on metallic and insulating substrates have been characterized by optical microscopy and surface analytical techniques. The potential for scale-up of this process to treatment of reactor components is discussed. (author)

  7. Advanced Anticorrosion Coating Materials Derived from Sunflower Oil with Bifunctional Properties.

    Science.gov (United States)

    Balakrishnan, Thiruparasakthi; Sathiyanarayanan, Sadagopan; Mayavan, Sundar

    2015-09-01

    High-performance barrier films preventing permeation of moisture, aggressive chloride ions, and corrosive acids are important for many industries ranging from food to aviation. In the current study, pristine sunflower oil was used to form uniform adherent films on iron (Fe) via a simple single-step thermal treatment (without involving any initiator/mediator/catalyst). Oxidation of oil on heating results in a highly conjugated (oxidized) crystalline lamellar network with interlayer separation of 0.445 nm on Fe. The electrochemical corrosion tests proved that the coating exhibits superior anticorrosion performance with high coating resistance (>10(9) ohm cm2) and low capacitance values (oil coatings developed in this study provided a two-fold protection of passivation from the oxide layer and barrier from polymeric films. It is clearly observed that there is no change in structure, morphology, or electrochemical properties even after a prolonged exposure time of 80 days. This work indicates the prospect of developing highly inert, environmentally green, nontoxic, and micrometer level passivating barrier coatings from more sustainable and renewable sources, which can be of interest for numerous applications. PMID:26292971

  8. Development and evaluation of electroless Ag-PTFE composite coatings with anti-microbial and anti-corrosion properties

    Science.gov (United States)

    Zhao, Q.; Liu, Y.; Wang, C.

    2005-12-01

    Electroless Ag-polytetrafluoroethylene (PTFE) composite coatings were prepared on stainless steel sheets. The existence and distribution of PTFE in the coatings were analysed with an energy dispersive X-ray microanalysis (EDX). The contact angle values and surface energies of the Ag-PTFE coatings, silver coating, stainless steel, titanium and E. coli Rosetta were measured. The experimental results showed that stainless steel surfaces coated with Ag-PTFE reduced E. coli attachment by 94-98%, compared with silver coating, stainless steel or titanium surfaces. The anti-bacterial mechanism of the Ag-PTFE composite coatings was explained with the extended Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. The anticorrosion properties of the Ag-PTFE composite coatings in 0.9% NaCl solution were studied. The results showed that the corrosion resistance of the Ag-PTFE composite coatings was superior to that of stainless steel 316L.

  9. Development of an environmentally benign anticorrosion coating for aluminum alloy using green pigments and organofunctional silanes

    Science.gov (United States)

    Yin, Zhangzhang

    Aerospace aluminum alloys such as Al alloy 2024-T3 and 7075-T6 are subject to localized corrosion due the existence of intermetallics containing Cu, Mg or Zn. Current protection measurement employs substantial use of chromate and high VOC organics, both of which are identified as environment and health hazards. The approach of this study is to utilize a combination of organofunctional silanes and a compatible inhibitor integrated into high-performance waterborne resins. First, an extensive pigment screening has been done to find replacements for chromates using the testing methodology for fast corrosion inhibition evaluation and pigment. Zinc phosphate and calcium zinc phosphomolybdate were found to have the best overall performance on Al alloys. Some new corrosion inhibitors were synthesized by chemical methods or modified by plasma polymerization for use in the coatings. Low-VOC, chromate-free primers (superprimer) were developed using these pigments with silane and acrylic-epoxy resins. The developed superprimer demonstrated good corrosion inhibition on aluminum substrates. The functions of inhibitor and silane in the coating were investigated. Both silane and inhibitor are critical for the performance of the superprimer. Silane was found to improve the adhesion of the coating to the substrate and also facilitate corrosion prevention. Addition of zinc phosphate to the coating improved the resistance of a scratched area against corrosion. The microstructure of the acrylic-epoxy superprimer coating was studied. SEM/EDAX revealed that the superprimer has a self-assembled stratified double-layer structure which accounts for the strong anti-corrosion performance of the zinc phosphate pigment. Zinc phosphate leaches out from the coating to actively protect the scratched area. The leaching of pigment was confirmed in the ICP-MS analysis and the leaching rate was measured. Coating-metal interface and the scribe of coated panels subjected to corrosion test was studied

  10. Influence of Functionalization of Nanocontainers on Self-Healing Anticorrosive Coatings.

    Science.gov (United States)

    Zheng, Zhaoliang; Schenderlein, Matthias; Huang, Xing; Brownbill, Nick J; Blanc, Frédéric; Shchukin, Dmitry

    2015-10-21

    Feedback coating based on pH-induced release of inhibitor from organosilyl-functionalized containers is considered as a compelling candidate to achieve smart self-healing corrosion protection. Four key factors that determine the overall coating performance include (1) the uptake and release capacity of containers, (2) prevention of the premature leakage, (3) compatibility of containers in coating matrix, and (4) cost and procedure simplicity consideration. The critical influence introduced by organosilyl-functionalization of containers is systematically demonstrated by investigating MCM-41 silica nanoparticles modified with ethylenediamine (en), en-4-oxobutanoic acid salt (en-COO(-)), and en-triacetate (en-(COO(-))3) with higher and lower organic contents. The properties of the modified silica nanoparticles as containers were mainly characterized by solid-state (13)C nuclear magnetic resonance, scanning and transmission electron microscopy, N2 sorption, thermogravimetric analysis, small-angle X-ray scattering, dynamic light scattering, and UV-vis spectroscopy. Finally, the self-healing ability and anticorrosive performances of hybrid coatings were examined through scanning vibrating electrode technique (SVET) and electrochemical impedance spectroscopy (EIS). We found that en-(COO(-))3-type functionalization with content of only 0.23 mmol/g performed the best as a candidate for establishing pH-induced release system because the resulting capped and loaded (C-L) functionalized silica nanocontainers (FSNs) exhibit high loading (26 wt %) and release (80%) capacities for inhibitor, prevention of premature leakage (less than 2%), good dispersibility in coating matrix, and cost effectiveness. PMID:26393678

  11. Anticorrosive field joint coating qualification, heat shrinkable sleeve; Qualificacao de revestimento anticorrosivo para juntas de campo, mantas termocontrateis

    Energy Technology Data Exchange (ETDEWEB)

    Cabral, Glaucia B.; Koebsch, Andre; Castinheiras Junior, Wilson [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2005-07-01

    The main objective of this job is to present the quality requirements fixed by PETROBRAS for anticorrosive field joint coating for buried pipelines, industrially coated with PE-3L. It describes the used system - polyethylene based heat shrinkable sleeve - comparing with the existent on the pipeline. So, it exposes the suppliers' qualification stages, which include test carried out for the materials, for the sleeve set and for the coating after its application on the joint field. Finally, it shows that the experience, which has been gotten in the qualification, consolidated the quality control systematic that have been carry out during the sleeves acquisition and application at the pipeline construction. (author)

  12. Multi-functional hybrid coatings containing silica nanoparticles and anti-corrosive acrylate monomer for scratch and corrosion resistance

    International Nuclear Information System (INIS)

    Multi-functional hybrid coatings having both anti-corrosion and scratch resistance were prepared from modified silica nanoparticles and functional acrylates. To improve the dispersion properties of silica nanoparticles in the organic/inorganic hybrid coatings, the surface of the nanoparticles was modified with γ-methacryloxypropyltrimethoxysilane. The coating solution could be prepared by mixing modified silica nanoparticles, tetrasiloxane acrylate, di-acrylate monomer containing an anti-corrosion functional group, acrylic acid, and an initiator in a solvent. The mixture was then dip-coated on iron substrates and finally polymerized by ultraviolet (UV) irradiation. Corrosion and scratch resistance of the coated iron was evaluated by electrochemical impedance spectroscopy (EIS) and a pencil hardness test, respectively. From the EIS results, the coatings with tetrasiloxane acrylate and di-acrylate did not show any decrease in impedance or phase angle, even after 50 days' exposure to 0.1 M NaCl electrolyte, whereas the conventional acrylate coatings started to fail after only 24 h. A hybrid coating containing the amine-quinone functional group exhibited excellent corrosion protection properties with 4-5H pencil hardness.

  13. Multi-functional hybrid coatings containing silica nanoparticles and anti-corrosive acrylate monomer for scratch and corrosion resistance

    Science.gov (United States)

    Seo, Ji Yeon; Han, Mijeong

    2011-01-01

    Multi-functional hybrid coatings having both anti-corrosion and scratch resistance were prepared from modified silica nanoparticles and functional acrylates. To improve the dispersion properties of silica nanoparticles in the organic/inorganic hybrid coatings, the surface of the nanoparticles was modified with γ-methacryloxypropyltrimethoxysilane. The coating solution could be prepared by mixing modified silica nanoparticles, tetrasiloxane acrylate, di-acrylate monomer containing an anti-corrosion functional group, acrylic acid, and an initiator in a solvent. The mixture was then dip-coated on iron substrates and finally polymerized by ultraviolet (UV) irradiation. Corrosion and scratch resistance of the coated iron was evaluated by electrochemical impedance spectroscopy (EIS) and a pencil hardness test, respectively. From the EIS results, the coatings with tetrasiloxane acrylate and di-acrylate did not show any decrease in impedance or phase angle, even after 50 days' exposure to 0.1 M NaCl electrolyte, whereas the conventional acrylate coatings started to fail after only 24 h. A hybrid coating containing the amine-quinone functional group exhibited excellent corrosion protection properties with 4-5H pencil hardness.

  14. Epoxy coatings for anticorrosion challenges: a link between chemistry and performance?

    Energy Technology Data Exchange (ETDEWEB)

    Sauvant-Moynot, Valerie; Schweitzer, Sylvie; Grenier, Jacky; Duval, Sebastien [Institut Francais du Petrole, 1 et 4 avenue Bois Preau, 92450 Rueil-Malmaison (France)

    2004-07-01

    Epoxy coatings have been used extensively for pipeline protection in the oil and gas industries over the past decades. Thank to their outstanding adhesive properties, epoxy resins are classically used for external coating of offshore pipelines although cathodic protection is applied. They provide corrosion protection while being used as neat coating or as primer layer in a three-layer coating. Protection of internal pipelines devoted to gas transport is another application of epoxy coatings. Whatever the case, the choice of the right epoxy formulation should be adapted to the service conditions, namely exposition medium and temperature, in order to provide efficient and sustainable corrosion protection. Epoxy resins constitute a wide family and classical formulations may not fulfill the requirements of today's challenges: as pipelines are require d to operate in more and more difficult conditions, coatings are expected to function in higher temperature conditions; additionally, practical conditions such as temporary injection of methanol make the environmental exposure of the epoxy coating harsher. Therefore, there is a need of a better knowledge of technical performance and limitations of high temperature epoxy resins. This paper examined the influence of the epoxy network architecture on their protection properties and durability while exposed to distilled / sea water at 110 deg. C and to methanol at room temperature. The objective was to investigate the link between resin chemistry and final performance with respect to anticorrosion applications. Five epoxy resin formulations mixed in stoichiometric proportions were cured and post-cured to infinite extent in order to achieve densely cross-linked networks exhibiting controlled and reproducible architectures. Gravimetric and pressurised differential scanning calorimetry (DSC) measurements were performed to evaluate the plasticization effect of both water and methanol on formulations under study. The related

  15. Development of anti-corrosion coating on low activation materials against fluoridation and oxidation in Flibe blanket environment

    International Nuclear Information System (INIS)

    W coating by vacuum plasma spray process and Cr coating by chromizing process were performed on fusion low activation materials, JLF-1 ferritic steel and NIFS-HEAT-2 vanadium alloy. The present study discusses feasibility of the coatings as anti-corrosion coating against fluoridation in Flibe for fusion low activation materials. Coatings were characterized by microstructural analysis and examination on chemical stability by corrosion tests. The corrosion tests were conducted with H2O-47% HF solution at RT and He-1% HF-0.06 H2O gas mixture at 823 K to simulate fluoridation and oxidation in Flibe. The coatings presented suppression of fluoride formation compared with JLF-1 or NIFS-HEAT-2, however weight loss due to WF6 formation was induced, and much Cr2O3 was formed.

  16. A Comparative Study on Graphene Oxide and Carbon Nanotube Reinforcement of PMMA-Siloxane-Silica Anticorrosive Coatings.

    Science.gov (United States)

    Harb, Samarah V; Pulcinelli, Sandra H; Santilli, Celso V; Knowles, Kevin M; Hammer, Peter

    2016-06-29

    Carbon nanotubes (CNTs) and graphene oxide (GO) have been used to reinforce PMMA-siloxane-silica nanocomposites considered to be promising candidates for environmentally compliant anticorrosive coatings. The organic-inorganic hybrids were prepared by benzoyl peroxide (BPO)-induced polymerization of methyl methacrylate (MMA) covalently bonded through 3-(trimethoxysilyl)propyl methacrylate (MPTS) to silica domains formed by hydrolytic condensation of tetraethoxysilane (TEOS). Single-walled carbon nanotubes and graphene oxide nanosheets were dispersed by surfactant addition and in a water/ethanol solution, respectively. These were added to PMMA-siloxane-silica hybrids at a carbon (CNT or GO) to silicon (TEOS and MPTS) molar ratio of 0.05% in two different matrices, both prepared at BPO/MMA molar ratios of 0.01 and 0.05. Atomic force microscopy and scanning electron microscopy showed very smooth, homogeneous, and defect-free surfaces of approximately 3-7 μm thick coatings deposited onto A1020 carbon steel by dip coating. Mechanical testing and thermogravimetric analysis confirmed that both additives CNT and GO improved the scratch resistance, adhesion, wear resistance, and thermal stability of PMMA-siloxane-silica coatings. Results of electrochemical impedance spectroscopy in 3.5% NaCl solution, discussed in terms of equivalent circuits, showed that the reinforced hybrid coatings act as a very efficient anticorrosive barrier with an impedance modulus up to 1 GΩ cm(2), approximately 5 orders of magnitude higher than that of bare carbon steel. In the case of GO addition, the high corrosion resistance was maintained for more than 6 months in saline medium. These results suggest that both carbon nanostructures can be used as structural reinforcement agents, improving the thermal and mechanical resistance of high performance anticorrosive PMMA-siloxane-silica coatings and thus extending their application range to abrasive environments. PMID:27266403

  17. Low-cost mussel inspired poly(catechol/polyamine) coating with superior anti-corrosion capability on copper.

    Science.gov (United States)

    Wu, Junjie; Cai, Chao; Zhou, Zhou; Qian, Hui; Zha, Fanglin; Guo, Jing; Feng, Bing; He, Tiexiang; Zhao, Ning; Xu, Jian

    2016-02-01

    A low-cost mussel inspired approach was developed to produce anti-corrosion coating on copper substrate. Catechol (CA) and polyamine (PA) were spontaneously polymerized to form adhesive coating of poly(cetechol/polyamine) (P(CA/PA)) onto copper surface and then P(CA/PA) was grafted by 1-dodecanethiol. The SEM, contact angle, XPS, FTIR and TG results demonstrated the formation of uniform, compact and thermal stable coatings through multiple interactions and chemically grafting. Electrochemical tests indicated of Cu-P(CA/PA)-SH possessed a highest corrosion potential of -81mV, a lowest corrosion current density of 0.15μA/cm(2), and a highest coating resistance of 57.19kΩcm(2), and also exhibit great long-term stability whether in solution immersion or salt spray tests. The remarkable anti-corrosion capability of Cu-P(CA/PA)-SH could be ascribed to the synergistic effect of the hydrophobicity, good stability, and strong wet adhesion of the mussel-inspired coating. This study provides an effective and cheap way for material protection and may give inspiration in the fields of material, biology and medicine relating to surface and interface engineering. PMID:26524257

  18. Adsorption of alginate and albumin on aluminum coatings inhibits adhesion of Escherichia coli and enhances the anti-corrosion performances of the coatings

    Energy Technology Data Exchange (ETDEWEB)

    He, Xiaoyan; Liu, Yi; Huang, Jing; Chen, Xiuyong; Ren, Kun; Li, Hua, E-mail: lihua@nimte.ac.cn

    2015-03-30

    Graphical abstract: - Highlights: • Adsorption behaviors of alginate and albumin on Al coatings were investigated at molecular level. • The adsorption inhibits effectively the colonization of Escherichia coli bacteria. • The adsorption alters the wettability of the Al coatings. • The conditioning layer enhances anti-corrosion performances of the Al coatings. - Abstract: Thermal-sprayed aluminum coatings have been extensively used as protective layers against corrosion for steel structures in the marine environment. The corrosion usually deteriorates from marine biofouling, yet the mechanism of accelerated corrosion of the coatings remains elusive. As the first stage participating in biofouling process, adsorption of molecules plays critical roles in mediating formation of biofilm. Here, we report at molecular level the adsorption behaviors of albumin and marine polysaccharide on arc-sprayed aluminum coatings and their influence on adhesion of Escherichia coli. The adsorption of alginate and albumin was characterized by infrared spectra analyses and atomic force microscopic observation. The adsorption inhibits effectively adhesion of the bacteria. Further investigation indicates that alginate/albumin altered the hydrophilicity/hydrophobicity of the coatings instead of impacting the survival of the bacteria to decline their adhesion. The conditioning layer composed of the molecules enhances anti-corrosion performances of the coatings.

  19. Adsorption of alginate and albumin on aluminum coatings inhibits adhesion of Escherichia coli and enhances the anti-corrosion performances of the coatings

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • Adsorption behaviors of alginate and albumin on Al coatings were investigated at molecular level. • The adsorption inhibits effectively the colonization of Escherichia coli bacteria. • The adsorption alters the wettability of the Al coatings. • The conditioning layer enhances anti-corrosion performances of the Al coatings. - Abstract: Thermal-sprayed aluminum coatings have been extensively used as protective layers against corrosion for steel structures in the marine environment. The corrosion usually deteriorates from marine biofouling, yet the mechanism of accelerated corrosion of the coatings remains elusive. As the first stage participating in biofouling process, adsorption of molecules plays critical roles in mediating formation of biofilm. Here, we report at molecular level the adsorption behaviors of albumin and marine polysaccharide on arc-sprayed aluminum coatings and their influence on adhesion of Escherichia coli. The adsorption of alginate and albumin was characterized by infrared spectra analyses and atomic force microscopic observation. The adsorption inhibits effectively adhesion of the bacteria. Further investigation indicates that alginate/albumin altered the hydrophilicity/hydrophobicity of the coatings instead of impacting the survival of the bacteria to decline their adhesion. The conditioning layer composed of the molecules enhances anti-corrosion performances of the coatings

  20. Microcapsule-based self-healing anticorrosive coatings: Capsule size, coating formulation, and exposure testing

    DEFF Research Database (Denmark)

    Nesterova, Tatyana; Dam-Johansen, Kim; Pedersen, Lars Thorslund;

    2012-01-01

    actual self-healing effect was not part of this work. The synthesis parameters investigated are stirrer geometry, agitation rate, temperature, and stabilizer concentration. It was found that an increase in stirring rate, correct choice of temperature, and a high stabilizer concentration all caused a...... (CPVC) was conducted using gloss measurements and a PVC ladder and found to be about 30 vol%. Due to the rather large capsules used (relative to the coating thickness), the low CPVC value can probably be ascribed to a fairly low packing efficiency in the coating, but this needs to be confirmed. Coating...

  1. Development of advanced Al coating processes for future application as anti-corrosion and T-permeation barriers

    International Nuclear Information System (INIS)

    Reduced ferritic-martensitic steels (e.g. Eurofer 97) are foreseen in future fusion technology as structural material in the HCLL concept, however, they show strong dissolution attack in Pb-15.7Li. Corrosion testing in Picolo loop revealed dramatically values of about 400 μm/year at flow rates of 0.22 m/s at 550 oC. This large amount of corrosion products is transported and will be deposited as precipitates at cooler positions with the risk of line blockages as found in Picolo testing. Thus, reliable TBM function claims anti-corrosion barriers. Previous studies (e.g. Hot-Dip Aluminization) showed that Al-based coatings have such anti-corrosion and also T-permeation reduction behavior. However, industrially relevant coating technologies are missing and Hot-Dip cannot fulfill low activation criteria. Electro-chemical deposition promises such features, however water-based systems are unqualified. The investigation of Al coating methods from non-aqueous systems succeeded in deposition of Al-scales in high reproducible and controllable thickness from two different types of electrolytes. The first one is based on organic aromates as electrolyte and the second variant uses organic salt melts (ionic liquids). The specific characteristics and advantages will be discussed as well as the formation of the protective scales after heat treatment and their behavior in Pb-15.7Li.

  2. Scratch Cell Test: A Simple, Cost Effective Screening Tool to Evaluate Self-Healing in Anti-Corrosion Coatings

    Science.gov (United States)

    Rani, Amitha; Somaiah, Durga; Megha; Poddar, Mitalee

    2014-09-01

    A quick and simple scratch cell set up to evaluate the self-healing of an hybrid sol-gel (ormosil) coating was fabricated. This methacrylate-based anti-corrosion coating was applied on the aerospace aluminium alloy AA2024-T3, and cured at room temperature. This technique of evaluation requires minimum instrumentation. The inhibitors cerium nitrate, benzotriazole and 8-hydroxy quinoline (8-HQ) were used in the study. The self-healing ability of the inhibitors decreased in the following order: 8-HQ, BTZ and Ce. 8-HQ showed the highest self-healing ability and was comparable to the commercial hexavalent chromium conversion coating—Alodine. Spectroscopic analysis of the electrolyte and EDX of the coatings indicated the movement of the inhibitor from the coating to the site of damage, thereby effecting self-healing. It was observed that an increased inhibitor concentration in the coatings did not accelerate the healing process. Inhibitor release was slower in the coatings doped with inhibitor-loaded nano-containers, when compared to inhibitor-spiked coatings. This property of controlled release is desirable in self-healing coatings. Electro impedance studies further confirmed self-healing efficiency of the coatings. The scratch cell study reported here is the first of its kind with the ormosil under study on AA2024-T3 aluminium alloy. The results are encouraging and warranty a quick and simple qualitative screening of the self-healing potential of the inhibitors with minimum instrumentation.

  3. Spray-on superhydrophobic coatings with high mechanical durability for anti-corrosion and anti-soiling applications

    Science.gov (United States)

    Schaeffer, Daniel A.; Polizos, Georgios; Smith, D. Barton; Rajic, Slobodan; Datskos, Panos G.; Hunter, Scott R.

    2014-10-01

    A superhydrophobic (SH) surface has many characteristics - of which are its self-cleaning and anti-corrosion functionalities - that are desirable across various industries. A superhydrophobic surface utilizes the right combination of surface chemistry and roughness that force water droplets to form high water contact angles (CA). This in turn allows droplets to easily roll off and pick up dirt and debris across the surface while also preventing water from penetrating the surface. We have developed a simple yet durable spray-on coating based on functionalized SiO2 nanoparticles that can easily be applied to surfaces including, but not limited to, optical sensors, photovoltaics, sights and lenses, textiles, construction materials, and electronic devices. In addition, these coatings exhibit practical mechanical and environmental durability that allow prolonged use of the coatings in harsh environments.

  4. An electrochemical method for evaluating the resistance to cathodic disbondment of anti-corrosion coatings on buried pipelines

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Methods for evaluating the resistance to cathodic disbondment (RCD) of anti-corrosion coatings on buried pipelines were reviewed. It is obvious that these traditional cathodic disbondment tests (CDT) have some disadvantages and the evaluated results are only simple figures and always rely on the subjective experience of the operator. A new electrochemical method for evaluating the RCD of coatings, that is, the potentiostatic evaluation method (PEM), was developed and studied. During potentiostatic anodic polarization testing, the changes of stable polarization current of specimens before and after cathodic disbonding (CD) were measured,and the degree of cathodic disbondment of the coating was quantitatively evaluated, among which the equivalent cathodic disbonded distance △D was suggested as a parameter for evaluating the RCD. A series of testing parameters of the PEM were determined in these experiments.

  5. Experience in application of front waves to detect cracks in anticorrosion coatings

    International Nuclear Information System (INIS)

    Ultrasonic testing method with head waves and specialized converters for detecting cracks in anticorrosion overlayers and in their fusion zone with base metal of inner surface of WWER reactor vessel nozzles of 850 mm in diameter are described. The method includes excitation of longitudinal waves propagating along the contact surface. Head ultrasonic waves are reflected from cracks located perpendicular to wave propagation direction and are recorded with a receiver. Comparative tests of testing techniques and head wave converters, experience of their application have shown high sensitivity and efficiency of this method when detecting cracks in anticorrosion overlayers

  6. Adsorption of alginate and albumin on aluminum coatings inhibits adhesion of Escherichia coli and enhances the anti-corrosion performances of the coatings

    Science.gov (United States)

    He, Xiaoyan; Liu, Yi; Huang, Jing; Chen, Xiuyong; Ren, Kun; Li, Hua

    2015-03-01

    Thermal-sprayed aluminum coatings have been extensively used as protective layers against corrosion for steel structures in the marine environment. The corrosion usually deteriorates from marine biofouling, yet the mechanism of accelerated corrosion of the coatings remains elusive. As the first stage participating in biofouling process, adsorption of molecules plays critical roles in mediating formation of biofilm. Here, we report at molecular level the adsorption behaviors of albumin and marine polysaccharide on arc-sprayed aluminum coatings and their influence on adhesion of Escherichia coli. The adsorption of alginate and albumin was characterized by infrared spectra analyses and atomic force microscopic observation. The adsorption inhibits effectively adhesion of the bacteria. Further investigation indicates that alginate/albumin altered the hydrophilicity/hydrophobicity of the coatings instead of impacting the survival of the bacteria to decline their adhesion. The conditioning layer composed of the molecules enhances anti-corrosion performances of the coatings.

  7. Investigation on microstructural, anti-corrosion and mechanical properties of doped Zn–Al–SnO2 metal matrix composite coating on mild steel

    International Nuclear Information System (INIS)

    Highlights: • Properties of nanocomposite Zn–Al coating containing SnO2 nanoparticles. • The morphology and structure of the coating were analysed. • The anticorrosion activities of the coating prepared. • The mechanical properties were found to improve with the amount of the SnO2 embedded. - Abstract: In this study, the microstructural, mechanical and anti-corrosion properties of nanocomposite Zn–Al coating containing SnO2 nanoparticles prepared from sulphates electrolyte by electrodeposition on mild steel substrate was investigated. The morphologies of the coating were analysed using SEM/EDS, AFM Raman and X-ray diffraction. The anticorrosion behaviour of the coating prepared with different concentrations of SnO2 (7 and 13 g/L) and potential of (0.3 and 0.5 V) was examined in 3.65% NaCl solution by using linear polarization techniques. The wear and hardness properties of the coatings were performed under accelerated reciprocating dry sliding wear tests and diamond micro-hardness tester respectively. The results obtained showed that the incorporation of SnO2 in the plating bath brings an increase in corrosion resistance and mechanical properties of Zn–Al–SnO2 composite coatings. The SEM images showed a homogeneous grain structure and finer morphology of the coatings. The hardness values was found to improve with the amount of the SnO2 embedded into the Zn–Al metal deposit and effective deposition parameters

  8. Improvement of anti-corrosive property for alloy plated steel sheet by UV curable organic-inorganic hybrid coatings

    International Nuclear Information System (INIS)

    According to its merits about high curing speed and low emission of volatile organic compounds, UV curable inorganic-organic coating technology has been developed as an alternative for toxic and carcinogenic chromate-based treatments for years. It is consistently observed that ultra-thin films offer excellent corrosion protection as well as paint adhesion to metals. Based on the tetra-ethylorthosilicate(TEOS) and methacryloxypropyl trimethoxysilane(MPTMS), inorganic sol was synthesized and formed hybrid networks with UV curable acrylic monomer, 6-hexanediol diacrylate(HDDA), trimethylolpropane triacrylate(TMPTA), pentaer-ythritol triacrylate(PETA). Several methods were used to test their properties such as salt spray test, potentiodynamic measurement, tape peel test, etc. It was shown that anti-corrosive property and stability of storage were affected by the molecular ratios of inorganic and organic compounds. It was not only the stability of storage, but had a excellent anti-corrosive, paint adhesive, and anti-solvent properties in a final molar ratios of 0.6/0.04/0.86/0.005 (TEOS/MPTMS/Acetone/HNO3) and 0.08/0.106/0.081/0.02 (TMPTA/HDDA/PETA/photo initiator)

  9. Preparation of silver-cuprous oxide/stearic acid composite coating with superhydrophobicity on copper substrate and evaluation of its friction-reducing and anticorrosion abilities

    International Nuclear Information System (INIS)

    A simple two-step solution immersion process was combined with surface-modification by stearic acid to prepare superhydrophobic coatings on copper substrates so as to reduce friction coefficient, increase wear resistance and improve the anticorrosion ability of copper. Briefly, cuprous oxide (Cu2O) crystal coating with uniform and compact tetrahedron structure was firstly created by immersing copper substrate in 2 mol L−1 NaOH solution. As-obtained Cu2O coating was then immersed in 0.33 mmol L−1 AgNO3 solution to incorporate silver nanoparticles, followed by modification with stearic acid (denoted as SA) coating to achieve hydrophobicity. The surface morphology and chemical composition of silver-cuprous oxide/stearic acid (denoted as Ag-Cu2O/SA) composite coating were investigated using a scanning electron microscope and an X-ray photoelectron spectroscope (XPS); and its phase structure was examined with an X-ray diffractometer (XRD). Moreover, the contact angle of water on as-prepared Ag-Cu2O/SA composite coating was measured, and its friction-reducing and anticorrosion abilities were evaluated. It was found that as-prepared Ag-Cu2O/SA composite coating has a water contact angle of as high as 152.4o and can provide effective friction-reducing, wear protection and anticorrosion protection for copper substrate, showing great potential for surface-modification of copper.

  10. Large-scale fabrication of superhydrophobic polyurethane/nano-Al2O3 coatings by suspension flame spraying for anti-corrosion applications

    Science.gov (United States)

    Chen, Xiuyong; Yuan, Jianhui; Huang, Jing; Ren, Kun; Liu, Yi; Lu, Shaoyang; Li, Hua

    2014-08-01

    This study aims to further enhance the anti-corrosion performances of Al coatings by constructing superhydrophobic surfaces. The Al coatings were initially arc-sprayed onto steel substrates, followed by deposition of polyurethane (PU)/nano-Al2O3 composites by a suspension flame spraying process. Large-scale corrosion-resistant superhydrophobic PU/nano-Al2O3-Al coatings were successfully fabricated. The coatings showed tunable superhydrophilicity/superhydrophobicity as achieved by changing the concentration of PU in the starting suspension. The layer containing 2.0 wt.%PU displayed excellent hydrophobicity with the contact angle of ∼151° and the sliding angle of ∼6.5° for water droplets. The constructed superhydrophobic coatings showed markedly improved anti-corrosion performances as assessed by electrochemical corrosion testing carried out in 3.5 wt.% NaCl solution. The PU/nano-Al2O3-Al coatings with superhydrophobicity and competitive anti-corrosion performances could be potentially used as protective layers for marine infrastructures. This study presents a promising approach for fabricatiing superhydrophobic coatings for corrosion-resistant applications.

  11. Al/Al2O3 Composite Coating Deposited by Flame Spraying for Marine Applications: Alumina Skeleton Enhances Anti-Corrosion and Wear Performances

    Science.gov (United States)

    Huang, Jing; Liu, Yi; Yuan, Jianhui; Li, Hua

    2014-04-01

    Here we report aluminum-alumina composite coatings fabricated by flame spraying for potential marine applications against both corrosion and wear. Microstructure examination suggested dense coating structures and the evenly distributed alumina splats formed hard skeleton connecting individual Al splats. The anti-corrosion and wear performance of the coatings were enhanced significantly by the addition of alumina. Failure analyses of the coatings after accelerated corrosion testing disclosed the intact alumina skeleton, which prevented further advancement of the corrosion. The results suggest that there is great potential for the cost-effective Al-Al2O3 coatings with tailorable alumina contents for application in the marine environment.

  12. Modifying the TiAlZr biomaterial surface with coating, for a better anticorrosive and antibacterial performance

    International Nuclear Information System (INIS)

    The paper investigates the increase of anticorrosive and antimicrobial properties of a composite elaborated by coating TiAlZr with Ag nanoparticles. Silver nanoparticles (AgNPs) were synthesized by reducing silver salts using NaBH4, and were characterized using dynamic light scattering instrument to determine the size distribution. The morphological and elemental analysis of Ag nanoparticles on the TiAlZr surface were performed with scanning electron microscopy (SEM) and energy disperse spectroscopy (EDS). Antibacterial activity was evaluated on the basis of the inhibition of the growth of Escherichia coli bacteria, and of the electrochemical parameters from dynamic polarization tests performed in Ringers bioliquid. An empirical model of antibacterial effect of silver nanoparticles at biointerface in the presence of TiAlZr implant was discussed.

  13. Electrochemical synthesis and anticorrosive properties of Nafion-poly(aniline-co-o-aminophenol) coatings on stainless steel

    International Nuclear Information System (INIS)

    The objective of this work was to compare the electrochemical behavior and possible anticorrosive properties of composite with Nafion, poly(aniline-co-o-aminophenol) (P(An-co-OAP)) and polyaniline (PAn) films with those of corresponding simple films. The electrochemical synthesis of polymer films was carried out on stainless steel AISI 304 (SS) surfaces by using the cyclic potential sweep (CPS) deposition. Scanning electron microscopy (SEM) was used for the characterization of the structure and morphology of deposited films. Evaluation of anticorrosive properties of films in 0.5 M H2SO4 without and with chlorides was achieved by monitoring the open circuit potential (EOC) of coated SS electrodes as well as by tracing the anodic current-potential polarization curves. These studies have shown that the SS remains in its passive state in the presence of polymer coatings. Composite with Nafion, P(An-co-OAP) and PAn films, keep their redox activity in chloride-containing acid solutions providing almost a complete protection of the SS substrate against pitting corrosion. These films prevent chloride exchange with solution because of the cation permselectivity of the Nafion membrane. The charge compensation during redox reactions occurs mainly by protons since sulfonate groups of Nafion act as dopants in composite films. The redox behavior of the Nafion-P(An-co-OAP) film is improved as compared with that of the Nafion-PAn film in both Cl--free and Cl--containing solutions. This behavior may be ascribed to the functional group -OH that facilitates charge compensation through proton during redox reactions

  14. Effect of polytetrafluoroethylene content on electrochemical anticorrosion behaviors of electroless deposited Ni-P and Ni-P-polytetrafluoroethylene coatings in seawater

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jianfei; Tian Jintao, E-mail: jttian@ouc.edu.cn; Liu Xuezhong; Yin Yansheng; Wang Xin

    2011-07-01

    The Ni-P and Ni-P-polytetrafluoroethylene (PTFE) coatings with various PTFE contents were electroless deposited on carbon steel and characterized through X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy. The microstructural morphologies of the coatings significantly varied with the PTFE content. As a result, the electrochemical anticorrosion capabilities were seriously decreased with the increase of the PTFE content. The coating with a trace PTFE (PTFE emulsion concentration of 0.2 mL/L in the plating bath) possessed excellent anticorrosion both in sterilized and unsterilized seawater which has been attributed to the absence of nano pores blocked by the incorporated trace PTFE nano particles.

  15. Effect of polytetrafluoroethylene content on electrochemical anticorrosion behaviors of electroless deposited Ni-P and Ni-P-polytetrafluoroethylene coatings in seawater

    International Nuclear Information System (INIS)

    The Ni-P and Ni-P-polytetrafluoroethylene (PTFE) coatings with various PTFE contents were electroless deposited on carbon steel and characterized through X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy. The microstructural morphologies of the coatings significantly varied with the PTFE content. As a result, the electrochemical anticorrosion capabilities were seriously decreased with the increase of the PTFE content. The coating with a trace PTFE (PTFE emulsion concentration of 0.2 mL/L in the plating bath) possessed excellent anticorrosion both in sterilized and unsterilized seawater which has been attributed to the absence of nano pores blocked by the incorporated trace PTFE nano particles.

  16. Facile fabrication of core–shell Pr6O11-ZnO modified silane coatings for anti-corrosion applications

    International Nuclear Information System (INIS)

    In this work, we have developed a facile and inexpensive method to fabricate anti-corrosive and hydrophobic surface with hierarchical micro and nano structures. We demonstrate for the first time the use of praseodymium oxide doped zinc oxide (Pr6O11-ZnO) nanocomposites loaded in a hybrid sol–gel (SiOx/ZrOx) layer, to effectively protect the underlying steel substrate from corrosion attack. The influence of Pr6O11-ZnO gives the surprising aspects based on active anti-corrosion and hydrophobic coatings. The spherical SiO2 particles have been successfully coated with Pr6O11-ZnO layer through sol–gel process. The resulted SiO2@Pr6O11-ZnO core–shell was characterized by Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and X-ray Photoelectron Spectroscopy (XPS). The barrier properties of the intact coatings were assessed by Electrochemical Impedance Spectroscopy (EIS). The fabrication of SiO2@Pr6O11-ZnO shows dual properties of hydrophobic and anti-corrosion micro/nanostructured sol–gel coatings follows a single/simple step coating procedure. This study has led to a better understanding factor influencing the anti-corrosion performance with embedded nanocomposites. These developments are particularly for silane network@ Pr6O11-ZnO for self-healing and self-cleaning behavior which can be designed for new protective coating system.

  17. Facile fabrication of core–shell Pr{sub 6}O{sub 11}-ZnO modified silane coatings for anti-corrosion applications

    Energy Technology Data Exchange (ETDEWEB)

    Jeeva Jothi, K.; Palanivelu, K., E-mail: kpalanivelucipet@gmail.com

    2014-01-01

    In this work, we have developed a facile and inexpensive method to fabricate anti-corrosive and hydrophobic surface with hierarchical micro and nano structures. We demonstrate for the first time the use of praseodymium oxide doped zinc oxide (Pr{sub 6}O{sub 11}-ZnO) nanocomposites loaded in a hybrid sol–gel (SiO{sub x}/ZrO{sub x}) layer, to effectively protect the underlying steel substrate from corrosion attack. The influence of Pr{sub 6}O{sub 11}-ZnO gives the surprising aspects based on active anti-corrosion and hydrophobic coatings. The spherical SiO{sub 2} particles have been successfully coated with Pr{sub 6}O{sub 11}-ZnO layer through sol–gel process. The resulted SiO{sub 2}@Pr{sub 6}O{sub 11}-ZnO core–shell was characterized by Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and X-ray Photoelectron Spectroscopy (XPS). The barrier properties of the intact coatings were assessed by Electrochemical Impedance Spectroscopy (EIS). The fabrication of SiO{sub 2}@Pr{sub 6}O{sub 11}-ZnO shows dual properties of hydrophobic and anti-corrosion micro/nanostructured sol–gel coatings follows a single/simple step coating procedure. This study has led to a better understanding factor influencing the anti-corrosion performance with embedded nanocomposites. These developments are particularly for silane network@ Pr{sub 6}O{sub 11}-ZnO for self-healing and self-cleaning behavior which can be designed for new protective coating system.

  18. Facile fabrication of core-shell Pr6O11-ZnO modified silane coatings for anti-corrosion applications

    Science.gov (United States)

    Jeeva Jothi, K.; Palanivelu, K.

    2014-01-01

    In this work, we have developed a facile and inexpensive method to fabricate anti-corrosive and hydrophobic surface with hierarchical micro and nano structures. We demonstrate for the first time the use of praseodymium oxide doped zinc oxide (Pr6O11-ZnO) nanocomposites loaded in a hybrid sol-gel (SiOx/ZrOx) layer, to effectively protect the underlying steel substrate from corrosion attack. The influence of Pr6O11-ZnO gives the surprising aspects based on active anti-corrosion and hydrophobic coatings. The spherical SiO2 particles have been successfully coated with Pr6O11-ZnO layer through sol-gel process. The resulted SiO2@Pr6O11-ZnO core-shell was characterized by Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and X-ray Photoelectron Spectroscopy (XPS). The barrier properties of the intact coatings were assessed by Electrochemical Impedance Spectroscopy (EIS). The fabrication of SiO2@Pr6O11-ZnO shows dual properties of hydrophobic and anti-corrosion micro/nanostructured sol-gel coatings follows a single/simple step coating procedure. This study has led to a better understanding factor influencing the anti-corrosion performance with embedded nanocomposites. These developments are particularly for silane network@ Pr6O11-ZnO for self-healing and self-cleaning behavior which can be designed for new protective coating system.

  19. Investigation on microstructural, anti-corrosion and mechanical properties of doped Zn–Al–SnO{sub 2} metal matrix composite coating on mild steel

    Energy Technology Data Exchange (ETDEWEB)

    Fayomi, O.S.I., E-mail: ojosundayfayomi3@gmail.com [Department of Chemical, Metallurgical and Materials Engineering, Tshwane University of Technology, P.M.B. X680, Pretoria (South Africa); Department of Mechanical Engineering, Covenant University, P.M.B 1023, Ota, Ogun State (Nigeria); Popoola, A.P.I. [Department of Chemical, Metallurgical and Materials Engineering, Tshwane University of Technology, P.M.B. X680, Pretoria (South Africa); Aigbodion, V.S. [Department of Metallurgical and Materials Engineering, University of Nigeria, Nsukka (Nigeria)

    2015-02-25

    Highlights: • Properties of nanocomposite Zn–Al coating containing SnO{sub 2} nanoparticles. • The morphology and structure of the coating were analysed. • The anticorrosion activities of the coating prepared. • The mechanical properties were found to improve with the amount of the SnO{sub 2} embedded. - Abstract: In this study, the microstructural, mechanical and anti-corrosion properties of nanocomposite Zn–Al coating containing SnO{sub 2} nanoparticles prepared from sulphates electrolyte by electrodeposition on mild steel substrate was investigated. The morphologies of the coating were analysed using SEM/EDS, AFM Raman and X-ray diffraction. The anticorrosion behaviour of the coating prepared with different concentrations of SnO{sub 2} (7 and 13 g/L) and potential of (0.3 and 0.5 V) was examined in 3.65% NaCl solution by using linear polarization techniques. The wear and hardness properties of the coatings were performed under accelerated reciprocating dry sliding wear tests and diamond micro-hardness tester respectively. The results obtained showed that the incorporation of SnO{sub 2} in the plating bath brings an increase in corrosion resistance and mechanical properties of Zn–Al–SnO{sub 2} composite coatings. The SEM images showed a homogeneous grain structure and finer morphology of the coatings. The hardness values was found to improve with the amount of the SnO{sub 2} embedded into the Zn–Al metal deposit and effective deposition parameters.

  20. Anti-corrosive Effects of Multi-Walled Carbon Nano Tube and Zinc Particle Shapes on Zinc Ethyl Silicate Coated Carbon Steel

    Energy Technology Data Exchange (ETDEWEB)

    Jang, JiMan; Shon, MinYoung; Kwak, SamTak [Pukyong National University, Busan (Korea, Republic of)

    2016-01-15

    Zinc ethyl silicate coatings containing multi walled carbon nanotubes (MWCNTs) were prepared, to which we added spherical and flake shaped zinc particles. The anti-corrosive effects of MWCNTs and zinc shapes on the zinc ethyl silicate coated carbon steel was examined, using electrochemical impedance spectroscopy and corrosion potential measurement. The results of EIS and corrosion potential measurement showed that the zinc ethyl silicate coated with flake shaped zinc particles and MWCNT showed lesser protection to corrosion. These outcomes were in agreement with previous results of corrosion potential and corrosion occurrence.

  1. Anticorrosion Coating of Carbon Nanotube/Polytetrafluoroethylene Composite Film on the Stainless Steel Bipolar Plate for Proton Exchange Membrane Fuel Cells

    OpenAIRE

    Yoshiyuki Show; Toshimitsu Nakashima; Yuta Fukami

    2013-01-01

    Composite film of carbon nanotube (CNT) and polytetrafluoroethylene (PTFE) was formed from dispersion fluids of CNT and PTFE. The composite film showed high electrical conductivity in the range of 0.1–13 S/cm and hydrophobic nature. This composite film was applied to stainless steel (SS) bipolar plates of the proton exchange membrane fuel cell (PEMFC) as anticorrosion film. This coating decreased the contact resistance between the surface of the bipolar plate and the membrane electrode assemb...

  2. Preparation of silver-cuprous oxide/stearic acid composite coating with superhydrophobicity on copper substrate and evaluation of its friction-reducing and anticorrosion abilities

    Energy Technology Data Exchange (ETDEWEB)

    Li, Peipei [Key Laboratory of Ministry of Education for Special Functional Materials, Henan University, Kaifeng 475004 (China); Chen, Xinhua [College of Chemistry and Chemical Engineering, Xuchang University, Xuchang 461000 (China); Yang, Guangbin; Yu, Laigui [Key Laboratory of Ministry of Education for Special Functional Materials, Henan University, Kaifeng 475004 (China); Zhang, Pingyu, E-mail: pingyu@henu.edu.cn [Key Laboratory of Ministry of Education for Special Functional Materials, Henan University, Kaifeng 475004 (China)

    2014-01-15

    A simple two-step solution immersion process was combined with surface-modification by stearic acid to prepare superhydrophobic coatings on copper substrates so as to reduce friction coefficient, increase wear resistance and improve the anticorrosion ability of copper. Briefly, cuprous oxide (Cu{sub 2}O) crystal coating with uniform and compact tetrahedron structure was firstly created by immersing copper substrate in 2 mol L{sup −1} NaOH solution. As-obtained Cu{sub 2}O coating was then immersed in 0.33 mmol L{sup −1} AgNO{sub 3} solution to incorporate silver nanoparticles, followed by modification with stearic acid (denoted as SA) coating to achieve hydrophobicity. The surface morphology and chemical composition of silver-cuprous oxide/stearic acid (denoted as Ag-Cu{sub 2}O/SA) composite coating were investigated using a scanning electron microscope and an X-ray photoelectron spectroscope (XPS); and its phase structure was examined with an X-ray diffractometer (XRD). Moreover, the contact angle of water on as-prepared Ag-Cu{sub 2}O/SA composite coating was measured, and its friction-reducing and anticorrosion abilities were evaluated. It was found that as-prepared Ag-Cu{sub 2}O/SA composite coating has a water contact angle of as high as 152.4{sup o} and can provide effective friction-reducing, wear protection and anticorrosion protection for copper substrate, showing great potential for surface-modification of copper.

  3. Cathodic delamination of seawater-immersed anticorrosive coatings: Mapping of parameters affecting the rate

    DEFF Research Database (Denmark)

    Sørensen, Per Aggerholm; Dam-Johansen, Kim; Weinell, C. E.;

    2010-01-01

    Abstract: Cathodic delamination is one of the major modes of failure for organic coatings immersed in seawater and refers to the weakening or loss of adhesion between the coating and the substrate. The diminished adhesion is the result of electrochemical reactions occurring at the coating...

  4. Effect of cerium (IV) ions on the anticorrosion properties of siloxane-poly(methyl methacrylate) based film applied on tin coated steel

    International Nuclear Information System (INIS)

    This work investigates the influence of the addition of cerium (IV) ions on the anticorrosion properties of organic-inorganic hybrid coatings applied to passivated tin coated steel. In order to evaluate the specific effect of cerium (IV) addition on nanostructural features of the organic and inorganic phases of the hybrid coating, the hydrolytic polycondensation of silicon alkoxide and the radical polymerization of the methyl methacrylate (MMA) function were induced separately. The corrosion resistance of the coatings was evaluated by means of linear polarization, Tafel type curves and electrochemical impedance measurements. The impedance results obtained for the hybrid coatings were discussed based on an electrical equivalent circuit used to fit the experimental data. The electrochemical results clearly showed the improvement of the protective properties of the organic-inorganic hybrid coating mainly when the cerium (IV) was added to the organic phase solution precursor, which seemed to be due to the formation of a more uniform and densely reticulated siloxane-PMMA film.

  5. Comparison of anti-corrosion properties of polyurethane based composite coatings with low infrared emissivity

    Energy Technology Data Exchange (ETDEWEB)

    Wang Yajun, E-mail: wangyajun609@163.com [College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Xu Guoyue; Yu Huijuan; Hu Chen; Yan Xiaoxing; Guo Tengchao; Li Jiufen [College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China)

    2011-03-01

    Four polyurethane resins, pure polyurethane (PU), epoxy modified polyurethane (EPU), fluorinated polyurethane (FPU) and epoxy modified fluorinated polyurethane (EFPU), with similar polyurethane backbone structure but different grafting group were used as organic adhesive for preparing low infrared emissivity coatings with an extremely low emissivity near 0.10 at 8-14 {mu}m, respectively. By using these four resins, the effect of different resin matrics on the corrosion protection of the low infrared emissivity coatings was investigated in detail by using neutral salt spray test, SEM and FTIR. It was found that the emissivity of the coatings with different resin matrics changes significantly in corrosion media. And the results indicated that the coating using EFPU as organic adhesive exhibited excellent corrosion resistance property which was mainly attributed to the presence of epoxy group and atomic fluorine in binder simultaneously.

  6. Reduction of cathodic delamination rates of anticorrosive coatings using free radical scavengers

    DEFF Research Database (Denmark)

    Sørensen, Per Aggerholm; Weinell, C. E.; Dam-Johansen, Kim;

    2010-01-01

    formed as intermediates in the cathodic reaction during the corrosion process. In this study, antioxidants (i.e., free radical scavengers and peroxide decomposers) have been incorporated into various generic types of coatings to investigate the effect of antioxidants on the rate of cathodic delamination......, copper, aluminum, galvanized steel, and brass also showed a reduction in the rate of cathodic delamination when the coating was modified with a free radical scavenger. The protective mechanism of free radical scavengers investigated for the primers are similar to that of antioxidants used for protection...... against photochemical degradation by UV-radiation of top coatings. Both substrate corrosion and degradation of a coating exposed to UV-radiation lead to the formation of free radicals as reactive intermediates....

  7. Comparison of anti-corrosion properties of polyurethane based composite coatings with low infrared emissivity

    International Nuclear Information System (INIS)

    Four polyurethane resins, pure polyurethane (PU), epoxy modified polyurethane (EPU), fluorinated polyurethane (FPU) and epoxy modified fluorinated polyurethane (EFPU), with similar polyurethane backbone structure but different grafting group were used as organic adhesive for preparing low infrared emissivity coatings with an extremely low emissivity near 0.10 at 8-14 μm, respectively. By using these four resins, the effect of different resin matrics on the corrosion protection of the low infrared emissivity coatings was investigated in detail by using neutral salt spray test, SEM and FTIR. It was found that the emissivity of the coatings with different resin matrics changes significantly in corrosion media. And the results indicated that the coating using EFPU as organic adhesive exhibited excellent corrosion resistance property which was mainly attributed to the presence of epoxy group and atomic fluorine in binder simultaneously.

  8. Anticorrosion efficiency of zinc-filled epoxy coatings containing conducting polymers and pigments

    Czech Academy of Sciences Publication Activity Database

    Kalendová, A.; Veselý, D.; Kohl, M.; Stejskal, Jaroslav

    2015-01-01

    Roč. 78, January (2015), s. 1-20. ISSN 0300-9440 Institutional support: RVO:61389013 Keywords : conducting polymer * zinc metal * organic coating Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.358, year: 2014

  9. Comparison of anti-corrosion properties of polyurethane based composite coatings with low infrared emissivity

    Science.gov (United States)

    Wang, Yajun; Xu, Guoyue; Yu, Huijuan; Hu, Chen; Yan, Xiaoxing; Guo, Tengchao; Li, Jiufen

    2011-03-01

    Four polyurethane resins, pure polyurethane (PU), epoxy modified polyurethane (EPU), fluorinated polyurethane (FPU) and epoxy modified fluorinated polyurethane (EFPU), with similar polyurethane backbone structure but different grafting group were used as organic adhesive for preparing low infrared emissivity coatings with an extremely low emissivity near 0.10 at 8-14 μm, respectively. By using these four resins, the effect of different resin matrics on the corrosion protection of the low infrared emissivity coatings was investigated in detail by using neutral salt spray test, SEM and FTIR. It was found that the emissivity of the coatings with different resin matrics changes significantly in corrosion media. And the results indicated that the coating using EFPU as organic adhesive exhibited excellent corrosion resistance property which was mainly attributed to the presence of epoxy group and atomic fluorine in binder simultaneously.

  10. Thermally Sprayable Anti-corrosion Marine Coatings Based on MAH-g-LDPE/UHMWPE Nanocomposites

    Science.gov (United States)

    Jeeva Jothi, K.; Santhoskumar, A. U.; Amanulla, Syed; Palanivelu, K.

    2014-12-01

    Polymer composite coatings based on low-density polyethylene (LDPE) and ultra-high-molecular-weight polyethylene (UHMWPE) blends were prepared for marine coatings. The incorporation of carboxyl moiety in the polymer blends of LDPE/UHMWPE was carried out by grafting with maleic anhydride (MAH) at varying concentrations of 1-8 wt.% using reactive extrusion process. An optimum percentage of grafting of 2.1% was achieved with 5 wt.% of maleic anhydride. Further, the nanocomposites of MAH-grafted-LDPE/UHMWPE blends were prepared by incorporating cloisite 15A nanoclay at varying concentrations of 1-4 wt.%. The polymer nanocomposites were converted into fine powders suitable for thermal spray having ≤200 μ particle size using cryogenic grinding. The effect of the intact coatings applied on grit-blasted mild steel by thermal spray technique was evaluated for abrasion resistance, adhesion strength, and corrosion resistance. The corrosion resistance of the polymer nanocomposites was studied by salt spray technique and Electrochemical Impedance Spectroscopy The abrasion resistance of coatings increases with increasing UHMWPE content in the blends. However, blends with higher concentration of UHMWPE resulted in coarse coatings with poor adhesion. The coatings with 90:10 MAH-grafted-LDPE/UHMWPE having 3 wt.% of nanoclay showed good abrasion resistance, adhesion strength, and better corrosion resistance.

  11. Development of Castor oil Modified Epoxy Polyurethane Anti-corrosion Coatings%蓖麻油改性环氧聚氨酯防腐蚀涂料的研制

    Institute of Scientific and Technical Information of China (English)

    李阳

    2012-01-01

    A kind of castor oil-modified epoxy polyurethane anti-corrosion coating was introduced. Castor oil modified isocyanate prepolymer and epoxy resin were used as basic materials,cheap talc, titanium dioxide, precipitated barium sulfate were used as pigment and filler , a kind of low cost and excellent performance anti-corrosion coating was developed. The performance of the coating developed under optimized conditions was detected. Castor oil modified epoxy polyurethane anti-corrosion coating and epoxy polyurethane anti-corrosion coating were compared. The results show that castor oil modified epoxy polyurethane anti-corrosion coating is better than epoxy polyurethane anti-corrosion coating in the aspects of acid - resistant, alkali - resistant and seawater - resistant.%介绍了一种蓖麻油改性的环氧聚氨酯防腐蚀涂料、以蓖麻油改性异氰酸酯预聚物和环氧树脂为基料,以价格较为低廉的滑石粉、钛白粉、沉淀硫酸钡为颜填料制备了成本较低,件能较为优异的防腐蚀涂料.检测了优化条件下制备的涂料的性能.以蓖麻油改性环氧聚氨酯防腐蚀涂料和未经蓖麻油改件的环氧聚氨酯防腐蚀涂料进行防腐蚀性能对比,蓖麻油改性环氧聚氨酯防腐蚀涂料的耐酸、碱、盐水等防腐蚀性能更好.

  12. Electrochemical and anticorrosion performances of zinc-rich and polyaniline powder coatings

    International Nuclear Information System (INIS)

    In this work, hydrochloride polyaniline (PANI-Cl) powder was incorporated as a conductive pigment into powder zinc-rich primer (ZRP) formulations in order to enhance the electronic conduction paths between zinc particles inside the coating and the steel substrate (i.e. percolation). Coatings were applied onto steel substrates and immersed in a 3% NaCl solution at ambient temperature. The protective properties and electrochemical behaviour of coatings were investigated by monitoring the free corrosion potential versus time and by using EIS. It was found that corrosion potential remains cathodic and constant for a long time up to 100 days of immersion. From EIS results, it was shown that the coatings exhibit larger impedance values than those observed with liquid or other zinc-rich powder formulations containing carbon black. From Raman spectroscopy results, it may be proposed that zinc particles in contact with PANI-Cl pigments were passivated. Other zinc particles remain still active which ensures the cathodic protection of the substrate. Moreover, coatings exhibit good barrier properties

  13. Roentgenological methods of evaluating protective properties of anticorrosion vanish- and paint coatings

    International Nuclear Information System (INIS)

    Corrosion processes under vanish-and-paint coatings at steel substrate are investigated by measuring intensities of X-ray reflexes of corrosion prducts. To increase the sensitivity of photography a method of slanted X-ray photography was used, the thickness of steel coating of substrate being less than the depth of ray penetration. Copper radiation was used, which is most easily absorbed by irn substrate. The method of diffracted radiaion monochromatization was applied to increase signal/background ratio. Multiple cycle measurement-test-measurement is quite possible

  14. Synthesis of durable microcapsules for self-healing anticorrosive coatings: A comparison of selected methods

    DEFF Research Database (Denmark)

    Nesterova, Tatyana; Dam-Johansen, Kim; Kiil, Søren

    2011-01-01

    Self-healing materials have the ability to ‘repair’ themselves upon exposure to an external stimulus. In the field of coatings, extensive laboratory research has been conducted on these so-called smart materials in the last decade. In the present work, a self-healing concept for epoxy-based antic......Self-healing materials have the ability to ‘repair’ themselves upon exposure to an external stimulus. In the field of coatings, extensive laboratory research has been conducted on these so-called smart materials in the last decade. In the present work, a self-healing concept for epoxy......, for the concept to work, microcapsules have to be strong enough to remain intact during storage and coating formulation and application. Furthermore, the capsules must remain stable for many years in the dry coating. Laboratory experiments, using four out of several encapsulation methods available...... in the literature, have been conducted to investigate the challenges associated with the synthesis of stable microcapsules. It was found that the nature of the core material strongly affects the microcapsule stability and performance. Furthermore, it was evident that experimental procedures developed for certain...

  15. Research Progress of High Performance Anticorrosive and Antifouling Warship Coatings%舰船高性能防腐蚀防污涂料研究进展

    Institute of Scientific and Technical Information of China (English)

    叶章基; 王晶晶; 蔺存国; 陈光章; 李瑛; 吴建华

    2014-01-01

    The development history and research status of marine anticorrosive and antifouling coating were introduced briefly.The latest research progresses of high performance anticorrosive and antifouling warship coatings were discussed emphatically.Self-polishing antifouling coatings based on acrylic acid zinc,acrylic acid copper and acrylic acid silane have been used widely after organictin self-polishing being prohibited.The technologies based on biocide grafting,degrad-able resin and surface micro-structure are the topic research in antifouling coating.The relationships between structure and degradation properties,mechanical properties of the degradable resin were discussed in detail.The relationships between surface mico-structure and antifouling properties of the fouling release coating were also discussed.The development direc-tions of anticorrosive coating are solventless (or high solid content)and long-term service with more and more strict envi-ronmental protection laws.This paper reported a method for improving wet adhesion and compactness,which can greatly improve mechanical properties and corrosion resistance of anticorrosive coatings.These anticorrosive and antifouling coat-ings meet the development needs of the ocean liner and deep-sea equipments.%简要论述了海洋防腐蚀防污涂料的发展历史和研究现状,重点论述了舰船高性能防腐蚀防污涂料的最新研究进展。有机锡自抛光防污涂料被禁止使用之后,基于丙烯酸锌、丙烯酸铜和丙烯酸硅烷酯的自抛光防污涂料得到了广泛应用。基于含防污功能基团树脂的防污涂料、基于降解树脂的防污涂料以及基于表面结构特性的防污涂料技术成为当前防污涂料研究的热点。文中详细报道了降解树脂的结构对降解性能及力学性能影响规律,以及表面结构特性对污损释放型防污涂料防污性能的影响规律。随着环境保护法规的日趋严格,防腐蚀涂料向无溶剂

  16. ANTICORROSION PROPERTIES OF EPOXY/GLASS FIBER COATINGS%玻璃纤维/环氧复合涂层耐腐蚀性能研究

    Institute of Scientific and Technical Information of China (English)

    郝永胜; 刘福春; 史洪微; 韩恩厚

    2011-01-01

    This paper focuses on the influence of ultra-fine glass fiber on the coating properties. Diglycidyl ether of bisphenol-A and diglycidyl ether of bisphenol-F epoxy resins were used as film former. Salt spray test and electrochemical impedance spectroscopy (EIS) were employed to characterize the anticorrosion properties of the coatings. Experimental results indicate that the diglycidyl ether of bisphenol-A epoxy resin can improve the coating hardness, while the diglycidyl ether of bisphenol-F epoxy resin has better anticorrosion properties.%研究了超细玻璃纤维对双酚A型(E44)和双酚F型(DER354)环氧树脂涂层体系力学性能和耐腐蚀性能的影响。通过盐雾试验和电化学阻抗谱(EIS)研究了涂层的耐腐蚀性。结果表明在双酚A和双酚F环氧树脂组成的涂料体系中,双酚A环氧树脂能够提高涂层的硬度,而双酚F环氧树脂能够提高涂层的耐腐蚀性。

  17. Anti-corrosive Conversion Coating on Aluminium Alloys Using High Temperature Steam

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Jellesen, Morten Stendahl; Ambat, Rajan

    Aluminium is extensively used as a structural material due to its excellent strength to weight ratio and corrosion resistance properties. The surface of aluminium under normal conditions has a thin oxide film (1-10nm) which provides corrosion resistance. However due to lower thickness, flaws and...... heterogeneity of native oxide layer does not provide long time corrosion resistance and adhesion of organic coating for a particular function in different environments. In order to enhance the corrosion resistance and adhesion of organic coating, the aluminium native oxide layer is treated to transform or...... chemistries based on pH and oxidizing capabilities. Treatment is carried out in an autoclave at a temperature of 110 – 112 °C and pressure of 5 Psi for varying times. The growth and composition of the oxide layer was investigated in detail as a function of microstructure using GD-OES, FEG-SEM, EDX, FIB...

  18. Efficient anti-corrosive coating of cold-rolled steel in a seawater environment using an oil-based graphene oxide ink

    Science.gov (United States)

    Singhbabu, Y. N.; Sivakumar, B.; Singh, J. K.; Bapari, H.; Pramanick, A. K.; Sahu, Ranjan K.

    2015-04-01

    We report the production of an efficient anti-corrosive coating of cold-rolled (CR) steel in a seawater environment (~3.5 wt% NaCl aqueous solution) using an oil-based graphene oxide ink. The graphene oxide was produced by heating Aeschynomene aspera plant as a carbon source at 1600 °C in an argon atmosphere. The ink was prepared by cup-milling the mixture of graphene oxide and sunflower oil for 10 min. The coating of ink on the CR steel was made using the dip-coating method, followed by curing at 350 °C for 10 min in air atmosphere. The results of the potentiodynamic polarization show that the corrosion rate of bare CR steel decreases nearly 10 000-fold by the ink coating. Furthermore, the salt spray test results show that the red rusting in the ink-coated CR steel is initiated after 100 h, in contrast to 24 h and 6 h in the case of oil-coated and bare CR steel, respectively. The significant decrease in the corrosion rate by the ink-coating is discussed based on the impermeability of graphene oxide to the corrosive ions.We report the production of an efficient anti-corrosive coating of cold-rolled (CR) steel in a seawater environment (~3.5 wt% NaCl aqueous solution) using an oil-based graphene oxide ink. The graphene oxide was produced by heating Aeschynomene aspera plant as a carbon source at 1600 °C in an argon atmosphere. The ink was prepared by cup-milling the mixture of graphene oxide and sunflower oil for 10 min. The coating of ink on the CR steel was made using the dip-coating method, followed by curing at 350 °C for 10 min in air atmosphere. The results of the potentiodynamic polarization show that the corrosion rate of bare CR steel decreases nearly 10 000-fold by the ink coating. Furthermore, the salt spray test results show that the red rusting in the ink-coated CR steel is initiated after 100 h, in contrast to 24 h and 6 h in the case of oil-coated and bare CR steel, respectively. The significant decrease in the corrosion rate by the ink-coating is

  19. Anticorrosion Coating of Carbon Nanotube/Polytetrafluoroethylene Composite Film on the Stainless Steel Bipolar Plate for Proton Exchange Membrane Fuel Cells

    Directory of Open Access Journals (Sweden)

    Yoshiyuki Show

    2013-01-01

    Full Text Available Composite film of carbon nanotube (CNT and polytetrafluoroethylene (PTFE was formed from dispersion fluids of CNT and PTFE. The composite film showed high electrical conductivity in the range of 0.1–13 S/cm and hydrophobic nature. This composite film was applied to stainless steel (SS bipolar plates of the proton exchange membrane fuel cell (PEMFC as anticorrosion film. This coating decreased the contact resistance between the surface of the bipolar plate and the membrane electrode assembly (MEA of the PEMFC. The output power of the fuel cell is increased by 1.6 times because the decrease in the contact resistance decreases the series resistance of the PEMFC. Moreover, the coating of this composite film protects the bipolar plate from the surface corrosion.

  20. The effects of addition of poly(vinyl) alcohol (PVA) as a green corrosion inhibitor to the phosphate conversion coating on the anticorrosion and adhesion properties of the epoxy coating on the steel substrate

    Energy Technology Data Exchange (ETDEWEB)

    Ramezanzadeh, B., E-mail: ramezanzadeh-bh@icrc.ac.ir; Vakili, H.; Amini, R.

    2015-02-01

    Highlights: • Room temperature zinc phosphate coating was applied on the surface of steel sample. • Poly(vinyl) alcohol was added to the phosphating bath as a green corrosion inhibitor. • The adhesion and anticorrosion properties of the epoxy coating were investigated. • PVA decreased the phosphate crystal size and porosity. • PVA enhanced the corrosion protection and adhesion properties of the epoxy coating. - Abstract: Steel substrates were chemically treated by room temperature zinc phosphate conversion coating. Poly(vinyl) alcohol (PVA) was added to the phosphate solution as a green corrosion inhibitor. Finally, the epoxy/polyamide coating was applied on the untreated and surface treated steel samples. The effects of PVA on the morphological properties of the phosphate coating were studied by scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and contact angle measuring device. The adhesion properties of the epoxy coatings applied on the surface treated samples were investigated by pull-off and cathodic delamination tests. Also, the anticorrosion properties of the epoxy coatings were studied by electrochemical impedance spectroscopy (EIS). Results showed that addition of PVA to the phosphate coating increased the population density of the phosphate crystals and decreased the phosphate grain size. The contact angle of the steel surface treated by Zn-PVA was lower than Zn treated one. The corrosion resistance of the epoxy coating was considerably increased on the steel substrate treated by zinc phosphate conversion coating containing PVA. PVA also enhanced the adhesion properties of the epoxy coating to the steel surface and decreased the cathodic delamination significantly.

  1. The effects of addition of poly(vinyl) alcohol (PVA) as a green corrosion inhibitor to the phosphate conversion coating on the anticorrosion and adhesion properties of the epoxy coating on the steel substrate

    International Nuclear Information System (INIS)

    Highlights: • Room temperature zinc phosphate coating was applied on the surface of steel sample. • Poly(vinyl) alcohol was added to the phosphating bath as a green corrosion inhibitor. • The adhesion and anticorrosion properties of the epoxy coating were investigated. • PVA decreased the phosphate crystal size and porosity. • PVA enhanced the corrosion protection and adhesion properties of the epoxy coating. - Abstract: Steel substrates were chemically treated by room temperature zinc phosphate conversion coating. Poly(vinyl) alcohol (PVA) was added to the phosphate solution as a green corrosion inhibitor. Finally, the epoxy/polyamide coating was applied on the untreated and surface treated steel samples. The effects of PVA on the morphological properties of the phosphate coating were studied by scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and contact angle measuring device. The adhesion properties of the epoxy coatings applied on the surface treated samples were investigated by pull-off and cathodic delamination tests. Also, the anticorrosion properties of the epoxy coatings were studied by electrochemical impedance spectroscopy (EIS). Results showed that addition of PVA to the phosphate coating increased the population density of the phosphate crystals and decreased the phosphate grain size. The contact angle of the steel surface treated by Zn-PVA was lower than Zn treated one. The corrosion resistance of the epoxy coating was considerably increased on the steel substrate treated by zinc phosphate conversion coating containing PVA. PVA also enhanced the adhesion properties of the epoxy coating to the steel surface and decreased the cathodic delamination significantly

  2. Effect of cerium on structure modifications of a hybrid sol–gel coating, its mechanical properties and anti-corrosion behavior

    International Nuclear Information System (INIS)

    Highlights: ► New sol–gel routes to replace chromates for corrosion protection of aluminum. ► Effect of cerium concentration on the microstructure of xerogel. ► Electrochemical and mechanical performances of hybrid coating with different cerium contents. ► Good correlation between the different results with an optimal cerium content of 0.01 M. -- Abstract: An organic–inorganic hybrid coating was developed to improve the corrosion resistance of the aluminum alloy AA 2024-T3. Organic and inorganic coatings derived from glycidoxypropyl-trimethoxysilane (GPTMS) and aluminum tri-sec-butoxide Al(OsBu)3, with different cerium contents, were deposited onto aluminum by dip-coating process. Corrosion resistance and mechanical properties were investigated by electrochemical impedance measurements and nano-indentation respectively. An optimal cerium concentration of 0.01 M was evidenced. To correlate and explain the hybrid coating performances in relation to the cerium content, NMR experiments were performed. It has been shown that when the cerium concentration in the hybrid is higher than 0.01 M there are important modifications in the hybrid structure that account for the mechanical properties and anti-corrosion behavior of the sol–gel coating.

  3. Effect of cerium on structure modifications of a hybrid sol–gel coating, its mechanical properties and anti-corrosion behavior

    Energy Technology Data Exchange (ETDEWEB)

    Cambon, Jean-Baptiste, E-mail: cambon@chimie.ups-tlse.fr [Institut Carnot CIRIMAT, Université de Toulouse, UMR CNRS 5085, 118 Route de Narbonne, 31062 Toulouse Cedex 9 (France); Esteban, Julien; Ansart, Florence; Bonino, Jean-Pierre; Turq, Viviane [Institut Carnot CIRIMAT, Université de Toulouse, UMR CNRS 5085, 118 Route de Narbonne, 31062 Toulouse Cedex 9 (France); Santagneli, S.H.; Santilli, C.V.; Pulcinelli, S.H. [Departamento Fısico-Química, Instituto de Química, Universidade Estadual Paulista, UNESP, CP 355, 14801-970 Araraquara, SP (Brazil)

    2012-11-15

    Highlights: ► New sol–gel routes to replace chromates for corrosion protection of aluminum. ► Effect of cerium concentration on the microstructure of xerogel. ► Electrochemical and mechanical performances of hybrid coating with different cerium contents. ► Good correlation between the different results with an optimal cerium content of 0.01 M. -- Abstract: An organic–inorganic hybrid coating was developed to improve the corrosion resistance of the aluminum alloy AA 2024-T3. Organic and inorganic coatings derived from glycidoxypropyl-trimethoxysilane (GPTMS) and aluminum tri-sec-butoxide Al(O{sup s}Bu){sub 3}, with different cerium contents, were deposited onto aluminum by dip-coating process. Corrosion resistance and mechanical properties were investigated by electrochemical impedance measurements and nano-indentation respectively. An optimal cerium concentration of 0.01 M was evidenced. To correlate and explain the hybrid coating performances in relation to the cerium content, NMR experiments were performed. It has been shown that when the cerium concentration in the hybrid is higher than 0.01 M there are important modifications in the hybrid structure that account for the mechanical properties and anti-corrosion behavior of the sol–gel coating.

  4. Development of anti-corrosive coating technique for alloy plated steel sheet using silane based organic-inorganic hybrid materials

    International Nuclear Information System (INIS)

    Silane surface treatments have been developed as an alternative for toxic and carcinogenic chromate-based treatments for years. It is consistently observed that ultra-thin films offer excellent corrosion protection as well as paint adhesion to metals. The silane performance is comparable to, or in some cases better than, that of chromate layers. Based on the tetra-ethylorthosilicate(TEOS) and methlyl trieethoxysilane(MTES), inorganic sol was synthesized and formed hybrid networks with SiO2 nano particle and polypropylene glycol(PPG) on Zn alloyed steel surface. According to SST results, addition of 10nm and 50nm SiO2 nanoparticle in synthesized solution improved anti-corrosion property by its shear stress relaxation effect during curing process. Also, SST results were shown that anti-corrosive property was affected by the amounts of organic compounds

  5. 2D and 3D alkaline earth metal carboxyphosphonate hybrids: Anti-corrosion coatings for metal surfaces

    International Nuclear Information System (INIS)

    Reactions of Mg2+ (1), Ca2+ (2), Sr2+ (3), or Ba2+ (4) salts with hydroxyphosphonoacetic acid (HPAA) at a 1:1 ratio yield M-HPAA layered coordination polymers. The crystal structures of 3 (two phases) and 4 have been determined by single crystal X-ray crystallography. Both stereoisomers (R and S) of HPAA are incorporated in the metal-HPAA materials. Synergistic combinations of Sr2+ or Ba2+ and HPAA at pH 7.3 are effective corrosion inhibitors for carbon steel, but are ineffective at pH 2.0. - Graphical abstract: Syntheses, characterization and crystal structures of metal-hydroxyphosphonoacetate hybrids are reported (Metal=Sr, Ba). 2D and 3D materials were prepared. Their anti-corrosion effects were studied at pH 2.0 and 7.3. It was found that anti-corrosion efficiency was demonstrated only at pH 7.3

  6. Development of anti-corrosive coating technique for alloy plated steel sheet using silane based organic-inorganic hybrid materials

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jongwon; Lee, Kyunghwang [Ulsan Industrial Technology Research Center, Ulsan (Korea, Republic of); Park, Byungkyu; Hong, Shinhyub [AK ChemTech Co., Ltd., Daejeon (Korea, Republic of)

    2013-06-15

    Silane surface treatments have been developed as an alternative for toxic and carcinogenic chromate-based treatments for years. It is consistently observed that ultra-thin films offer excellent corrosion protection as well as paint adhesion to metals. The silane performance is comparable to, or in some cases better than, that of chromate layers. Based on the tetra-ethylorthosilicate(TEOS) and methlyl trieethoxysilane(MTES), inorganic sol was synthesized and formed hybrid networks with SiO{sub 2} nano particle and polypropylene glycol(PPG) on Zn alloyed steel surface. According to SST results, addition of 10nm and 50nm SiO{sub 2} nanoparticle in synthesized solution improved anti-corrosion property by its shear stress relaxation effect during curing process. Also, SST results were shown that anti-corrosive property was affected by the amounts of organic compounds.

  7. Anticorrosion/antifouling properties of bacterial spore-loaded sol-gel type coating for mild steel in saline marine condition: a case of thermophilic strain of Bacillus licheniformis

    OpenAIRE

    Eduok, Ubong; Suleiman, Rami; Gittens, Jeanette; Khaled, Mazen; Smith, Thomas J.; Akid, Robert; El Ali, Bassam; Khalil, Amjad

    2015-01-01

    This work reports the performance of a sol-gel type coating encapsulated with biofilm of inoculums of protective thermophilic strain of Bacillus licheniformis endospores isolated from the Gazan hot springs- Saudi Arabia for the inhibition of marine fouling and corrosion protection of S36-grade mild steel in 3.5 wt% NaCl medium. In order to improve its anticorrosion properties, the hybrid sol-gel coating is further doped with zinc molybdate (MOLY) and zinc aluminum polyphosphate (Z...

  8. Simultaneous determination of rare earth elements in ore and anti-corrosion coating samples using a portable capillary electrophoresis instrument with contactless conductivity detection.

    Science.gov (United States)

    Nguyen, Thi Anh Huong; Nguyen, Van Ri; Le, Duc Dung; Nguyen, Thi Thanh Binh; Cao, Van Hoang; Nguyen, Thi Kim Dung; Sáiz, Jorge; Hauser, Peter C; Mai, Thanh Duc

    2016-07-29

    The employment of an in-house-made capillary electrophoresis (CE) instrument with capacitively coupled contactless conductivity detection (C(4)D) as a simple and inexpensive solution for simultaneous determination of many rare earth elements (REEs) in ore samples from Vietnam, as well as in anti-corrosion coating samples is reported. 14 REEs (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) were determined using an electrolyte composed of 20mM arginine and 10mM α-hydroxyisobutyric acid adjusted to pH 4.2 with acetic acid. The best detection limit achieved was 0.24mg/L using the developed CE-C(4)D method. Good agreement between results from CE-C(4)D and the confirmation method (ICP-MS) was achieved, with a coefficient of determination (r(2)) for the two pairs of data of 0.998. PMID:27363736

  9. Formulation of anticorrosive paints employing conducting polymers

    OpenAIRE

    Martí Barroso, Mireia

    2013-01-01

    The intention and purpose of the present thesis is to prepare a series of protective coatings using some conducting polymers (CPs) as corrosion inhibitors. The use of organic paints is the most common method for corrosion prevention. Anticorrosive coatings form a class of high-performance systems with a very wide range of applications and being classified in two broad groups: heavy-duty coatings, for high performance, and light-duty coatings, for medium performance. The first class being requ...

  10. Effects of surface treatment of aluminium alloy 1050 on the adhesion and anticorrosion properties of the epoxy coating

    Energy Technology Data Exchange (ETDEWEB)

    Sharifi Golru, S., E-mail: samanesharifi@aut.ac.ir [Department of Polymer Engineering and Color Technology, Amirkabir University of Technology, P.O. Box 15875-4413 Tehran (Iran, Islamic Republic of); Attar, M.M., E-mail: attar@aut.ac.ir [Department of Polymer Engineering and Color Technology, Amirkabir University of Technology, P.O. Box 15875-4413 Tehran (Iran, Islamic Republic of); Ramezanzadeh, B. [Department of Surface Coating and Corrosion, Institute for Color Science and Technology, No. 59,Vafamanesh St, Hosainabad Sq, Lavizan, Tehran (Iran, Islamic Republic of)

    2015-08-01

    Highlights: • Aluminium alloy 1050 was treated by zirconium-based (Zr) conversion coating. • The surface morphology and surface free energy of the samples were obtained. • The adhesion properties of the epoxy coating was studied on the treated samples. • The corrosion resistance of the epoxy coating was enhanced on treated samples. - Abstract: The objective of this work is to investigate the effects of zirconium-based (Zr) conversion coating on the adhesion properties and corrosion resistance of an epoxy/polyamide coating applied on the aluminium alloy 1050 (AA1050). Field emission scanning electron microscope (FE-SEM), energy dispersive X-ray spectrum (EDS), atomic force microscope (AFM) and contact angle measuring device were employed in order to characterize the surface characteristics of the Zr treated AA1050 samples. The epoxy/polyamide coating was applied on the untreated and Zr treated samples. The epoxy coating adhesion to the aluminium substrate was evaluated by pull-off test before and after 30 days immersion in 3.5% w/w NaCl solution. In addition, the electrochemical impedance spectroscopy (EIS) and salt spray tests were employed to characterize the corrosion protection properties of the epoxy coating applied on the AA1050 samples. Results revealed that the surface treatment of AA1050 by zirconium conversion coating resulted in the increase of surface free energy and surface roughness. The dry and recovery (adhesion strength after 30 days immersion in the 3.5 wt% NaCl solution) adhesion strengths of the coatings applied on the Zr treated aluminium samples were greater than untreated sample. In addition, the adhesion loss of the coating applied on the Zr treated aluminium substrate was lower than other samples. Also, the results obtained from EIS and salt spray test clearly revealed that the Zr conversion coating could enhance the corrosion protective performance of the epoxy coating significantly.

  11. Effects of surface treatment of aluminium alloy 1050 on the adhesion and anticorrosion properties of the epoxy coating

    International Nuclear Information System (INIS)

    Highlights: • Aluminium alloy 1050 was treated by zirconium-based (Zr) conversion coating. • The surface morphology and surface free energy of the samples were obtained. • The adhesion properties of the epoxy coating was studied on the treated samples. • The corrosion resistance of the epoxy coating was enhanced on treated samples. - Abstract: The objective of this work is to investigate the effects of zirconium-based (Zr) conversion coating on the adhesion properties and corrosion resistance of an epoxy/polyamide coating applied on the aluminium alloy 1050 (AA1050). Field emission scanning electron microscope (FE-SEM), energy dispersive X-ray spectrum (EDS), atomic force microscope (AFM) and contact angle measuring device were employed in order to characterize the surface characteristics of the Zr treated AA1050 samples. The epoxy/polyamide coating was applied on the untreated and Zr treated samples. The epoxy coating adhesion to the aluminium substrate was evaluated by pull-off test before and after 30 days immersion in 3.5% w/w NaCl solution. In addition, the electrochemical impedance spectroscopy (EIS) and salt spray tests were employed to characterize the corrosion protection properties of the epoxy coating applied on the AA1050 samples. Results revealed that the surface treatment of AA1050 by zirconium conversion coating resulted in the increase of surface free energy and surface roughness. The dry and recovery (adhesion strength after 30 days immersion in the 3.5 wt% NaCl solution) adhesion strengths of the coatings applied on the Zr treated aluminium samples were greater than untreated sample. In addition, the adhesion loss of the coating applied on the Zr treated aluminium substrate was lower than other samples. Also, the results obtained from EIS and salt spray test clearly revealed that the Zr conversion coating could enhance the corrosion protective performance of the epoxy coating significantly

  12. Encapsulated cerium nitrate inhibitors to provide high-performance anti-corrosion sol-gel coatings on mild steel

    International Nuclear Information System (INIS)

    A rapid cure silane sol-gel coating containing encapsulated corrosion inhibitors that can be applied to a mild steel substrate to form a crack-free coating has been developed. The benefit of this system is that it appears to emulate the protection mechanism found with traditional chrome (VI) based systems, but without the environmental disadvantages, namely that it is non-toxic and non-carcinogenic. The high corrosion resistance performance of this coating is derived from the combination of the hydrophobic nature of the sol-gel coating and the presence of the encapsulated rare earth corrosion inhibitor which can be released at defects within the coating resulting in cerium hydroxide precipitation which hinders the reduction reaction at cathodic sites. The proposed mechanism for this protection is based upon an evaluation of the barrier properties of the coating using electrochemical impedance spectroscopy and long-term immersion/salt spray tests

  13. Anticorrosion protection of uranium

    International Nuclear Information System (INIS)

    Uranium in atmospheric conditions is non-stable. Sloughing products are being generated on its surface during storage or use. These corrosion products make many difficulties because of necessity to provide personnel safety. Besides, uranium corrosion may cause damage in parts. The first works devoted to uranium corrosion were performed in the framework of the USA Manhattan Project in the early forties of last century. Various methods of uranium protection were investigated, among them the galvanic one was the most studied. Later on the galvanic technology was patented. The works on this problem remains urgent up to the present time. In Russia, many methods of uranium corrosion protection, mainly against atmospheric corrosion, were tried on. In particular, such methods as diffusion zinc and paint coating were investigated. In the first case, a complex intermetallic U-Zn compound was formed but its protection was not reliable enough, this protection system was inconvenient and uncertain and that is why an additional paint coating was necessary. In the case of paint coatings another problem appeared. It was necessary to find such a coating where gas-permeability would prevail over water-permeability. Otherwise significant uranium corrosion occurs. This circumstance together with low mechanical resistance of paint coatings does not allow to use paint coating for long-term protection of uranium. Currently, there are following methods of uranium protection: ion-plasma, galvanic and thermo-vacuum annealing. These are described in this paper. In the end the issue of corrosion protection in reactor core zones is addressed. Here the greatest difficulties are caused when enriched uranium heated up to 500 deg. C needs anticorrosion protection. In this case various metal coatings are not reliable because of brittle inter-metallide formation. The reliable protection may be provided only up to the temperature plus 400 - 500 deg. C with the help of galvanic copper coating since

  14. Optimal conditions for the deposition of novel anticorrosive coatings by RF magnetron sputtering for aluminum alloy AA6082

    International Nuclear Information System (INIS)

    Highlights: • Non-conventional technique for improving the corrosion resistance of aluminum alloys. • Effect of the deposition parameters: power, substrate temperature and deposition time. • Changes in the crystallinity of the coatings are observed with the temperature. • The structure of these coatings is found to be dependent on the nature of the substrate. • La coatings can provide a better physical barrier to inhibit the corrosion attack. - Abstract: Cerium and lanthanum coatings were deposited on glass, silicon (1 0 0), and aluminum alloy by RF magnetron sputtering in which several experimental conditions such as power, substrate temperature, and deposition time were varied, using pure CeO2 and La2O3 targets. The effect of deposition parameters on the bonding structure, surface morphology and properties against corrosion of rare earth (RE) coatings formed on metallic substrate was reported. The microstructure and chemistry of the thin film were characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), and X-ray photoelectron spectroscopy (XPS); whereas their use as corrosion resistant coatings was studied in aqueous NaCl solution (3.0 wt%) by using polarization curves. Variations in these properties were observed by increasing the substrate temperature which modifies the crystallinity of the rare earth coatings. XRD and XPS findings indicate that the cerium coatings are composed by CeO2 and a significant quantity of Ce2O3 due to oxygen deficiency in the sputtering chamber, whereas La2O3/La(OH)3 and some La intermetallic compounds are detected in the lanthanum films. Variations in the Ecorr and Icorr were found as a function of the thickness, texture, and morphology of the as-prepared coatings

  15. Optimal conditions for the deposition of novel anticorrosive coatings by RF magnetron sputtering for aluminum alloy AA6082

    Energy Technology Data Exchange (ETDEWEB)

    Brachetti-Sibaja, S.B. [Instituto Politécnico Nacional, Postgraduate Student of CICATA-Unidad Altamira (Mexico); Instituto Tecnológico de Cd. Madero, Cd. Madero, Tamaulipas (Mexico); Domínguez-Crespo, M.A., E-mail: mdominguezc@ipn.mx [CICATA-Altamira, Instituto Politécnico Nacional, IPN Km 14.5 Carretera Tampico-Puerto Industrial Altamira, C.P. 89600 Altamira, Tamaulipas (Mexico); Rodil, S.E. [Universidad Nacional Autónoma de México, IIM, D.F. (Mexico); Torres-Huerta, A.M. [CICATA-Altamira, Instituto Politécnico Nacional, IPN Km 14.5 Carretera Tampico-Puerto Industrial Altamira, C.P. 89600 Altamira, Tamaulipas (Mexico)

    2014-12-05

    Highlights: • Non-conventional technique for improving the corrosion resistance of aluminum alloys. • Effect of the deposition parameters: power, substrate temperature and deposition time. • Changes in the crystallinity of the coatings are observed with the temperature. • The structure of these coatings is found to be dependent on the nature of the substrate. • La coatings can provide a better physical barrier to inhibit the corrosion attack. - Abstract: Cerium and lanthanum coatings were deposited on glass, silicon (1 0 0), and aluminum alloy by RF magnetron sputtering in which several experimental conditions such as power, substrate temperature, and deposition time were varied, using pure CeO{sub 2} and La{sub 2}O{sub 3} targets. The effect of deposition parameters on the bonding structure, surface morphology and properties against corrosion of rare earth (RE) coatings formed on metallic substrate was reported. The microstructure and chemistry of the thin film were characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), and X-ray photoelectron spectroscopy (XPS); whereas their use as corrosion resistant coatings was studied in aqueous NaCl solution (3.0 wt%) by using polarization curves. Variations in these properties were observed by increasing the substrate temperature which modifies the crystallinity of the rare earth coatings. XRD and XPS findings indicate that the cerium coatings are composed by CeO{sub 2} and a significant quantity of Ce{sub 2}O{sub 3} due to oxygen deficiency in the sputtering chamber, whereas La{sub 2}O{sub 3}/La(OH){sub 3} and some La intermetallic compounds are detected in the lanthanum films. Variations in the E{sub corr} and I{sub corr} were found as a function of the thickness, texture, and morphology of the as-prepared coatings.

  16. Synergism in anticorrosive paints

    Indian Academy of Sciences (India)

    G BLUSTEIN; C DEYÁ; R ROMAGNOLI

    2016-06-01

    The present work depicts synergism anticorrosive behaviour between zinc hypophosphite and zinc phosphate in a commercial pigment mixture. Also, the performance of anticorrosive paints was evaluated. Synergism anticorrosive behaviour was evaluated by corrosion potential and linear polarization measurements in pigment suspensions. The protective layer obtained with this pigment mixture was investigated by scanning electron microscopy (SEM). Then, the anticorrosive properties of the pigment were assessed by incorporating it into alkyd and epoxy paints which were evaluated by salt spray test and electrochemical noise technique. The morphology and the nature of the protective layer grown under the paint film were also studied by SEM. Experimental results showed that improved anticorrosion protection is achieved in paints with reduced zinc phosphate contents as a consequence of the synergistic interaction between zinc hypophosphite and the other components of the pigment mixture. The electrochemical noise technique proved to be adequate to monitor corrosion in painted panels and is able to detectcorrosion under the paint film from very early stages. This paper identified the need to study synergism between anticorrosive pigments to try to reduce the phosphate content in anticorrosive paints.

  17. Anticorrosive effects and in vitro cytocompatibility of calcium silicate/zinc-doped hydroxyapatite composite coatings on titanium

    Science.gov (United States)

    Huang, Yong; Zhang, Honglei; Qiao, Haixia; Nian, Xiaofeng; Zhang, Xuejiao; Wang, Wendong; Zhang, Xiaoyun; Chang, Xiaotong; Han, Shuguang; Pang, Xiaofeng

    2015-12-01

    This work elucidated the corrosion resistance and cytocompatibility of electroplated Zn- and Si-containing bioactive calcium silicate/zinc-doped hydroxyapatite (ZnHA/CS) ceramic coatings on commercially pure titanium (CP-Ti). The formation of ZnHA/CS coating was investigated through Fourier transform infrared spectroscopy, X-ray diffraction (XRD), scanning electron microscopy, energy dispersive X-ray and inductively coupled plasma analyses. The XRD image showed that the reaction layer was mainly composed of HA and CaSiO3. The fabricated ZnHA/CS coatings presented a porous structure and appropriate thickness for possible applications in orthopaedic surgery. Potentiodynamic polarization tests showed that ZnHA/CS coatings exhibited higher corrosion resistance than CP-Ti. Dissolution tests on the coating also revealed that Si4+ and Zn2+ were leached at low levels. Moreover, MC3T3-E1 cells cultured on ZnHA/CS featured improved cell morphology, adhesion, spreading, proliferation and expression of alkaline phosphatase than those cultured on HA. The high cytocompatibility of ZnHA/CS could be mainly attributed to the combination of micro-porous surface effects and ion release (Zn2+ and Si4+). All these results indicate that ZnHA/CS composite-coated CP-Ti may be a potential material for orthopaedic applications.

  18. Application of One Component Moisture Curing Polyurea/Polyurethane Anticorrosion Coatings in the Anticorrosion Maintenance of Steel Structure Bridge%单组分湿固化聚脲/聚氨酯防腐涂料在钢结构大桥防腐维修中的应用

    Institute of Scientific and Technical Information of China (English)

    王道前; 肖国亮; 欧阳明

    2011-01-01

    The steel beam bridge structure anticorrosion design and performance of three bridges on the river Huangpujiang were introduced. Based on the corrosion ambient condition, the disadvantages and limitations of traditional epoxy system, a bridge anticorrosion repair procedure were recommended. The performance characteristics and application procedure of the one component moisture curing polyurea/polyurethane coatings were described, and compared it with two components surface tolerant coatings.%介绍了黄浦江上南浦、杨浦、徐浦3座大桥钢箱梁结构的涂装情况。根据3座大桥所处的腐蚀环境和传统环氧涂料施工的局限性,提出了大桥防腐维修方案。阐述了单组分湿固化聚脲/聚氨酯涂料的性能特点和施工工艺流程,并与双组分低表面处理涂料的性能进行比较。

  19. Evaluation of the anti-corrosive effect of acid pickling and sol-gel coating on magnesium AZ31 alloy

    International Nuclear Information System (INIS)

    The effect of different acid pre-treatment procedures on the corrosion of magnesium AZ31 alloy was compared by measuring the amount of hydrogen gas formed when the surface was in contact with aqueous 5% sodium chloride solution. A 4-7 μm thick sol-gel coating prepared by phosphoric acid catalyzed sol-gel processing of a methyltriethoxysilane/tetraethoxysilane mixture was applied to the differently pre-treated magnesium surfaces. The corrosion rate of the alloy decreased by a factor of up to 60 by combination of acid pickling and sol-gel coating. The addition of triethylphosphate or 1,2,4-triazole as corrosion inhibitors led to further improvements. Composition and texture of the films was investigated by scanning electron microscopy and energy dispersive X-ray analysis

  20. Development and characterization of silicone/phosphorus modified epoxy materials and their application as anticorrosion and antifouling coatings

    OpenAIRE

    T. Balakrishnan; Alagar, M.; Denchev, Z.; Kumar, S. Ananda

    2006-01-01

    Epoxy resin is chosen for our present study owing to its exceptional combination of properties such as easy processing, high safety, excellent solvent and chemical resistance, toughness, low shrinkage on cure, good electrical, mechanical and corrosion resistance with excellent adhesion to many substrates. This versatility in formulation made epoxy resins widely applied for surface coatings, adhesives, laminates, composites, potting, painting materials, encapsulant for semiconductor and insula...

  1. The new aspects of the anticorrosive ZnO@SiO2 core-shell NPs in stabilizing of the electrolytic Ni bath and the Ni coating structure; electrochemical behavior of the resulting nano-composite coatings.

    Science.gov (United States)

    Sharifalhoseini, Zahra; Entezari, Mohammad H

    2015-10-01

    The pure phase of the ZnO nanoparticles (NPs) as anticorrosive pigments was synthesized by the sonication method. The surfaces of the sono-synthesized nanoparticles were covered with the protective silica layer. The durability of the coated and uncoated ZnO NPs in the used electrolytic Ni bath was determined by flame atomic absorption spectrometry. In the present research the multicomponent Ni bath as the complex medium was replaced by the simple one. The used nickel-plating bath was just composed of the Ni salts (as the sources of the Ni(2+) ions) to better clarify the influence of the presence of the ZnO@SiO2 core-shell NPs on the stability of the medium. The effect of ZnO@SiO2 NPs incorporation on the morphology of the solid electroformed Ni deposit was studied by scanning electron microscopy (SEM). Furthermore, the influence of the co-deposited particles in the Ni matrix on the corrosion resistance of the Ni coating was evaluated by the electrochemical methods including linear polarization resistance (LPR) and Tafel extrapolation. PMID:26057943

  2. Electrochemical anticorrosion performance evaluation of Al2O3 coatings deposited by MOCVD on an industrial brass substrate

    International Nuclear Information System (INIS)

    Alumina (Al2O3) coatings of different thickness were deposited on OT59 brass substrate (BS) using the metal organic chemical vapour deposition (MOCVD) technique to evaluate the corrosion performance by EIS measurements. The used precursor was dimethyl-aluminium-isopropoxide. Electrochemical characterizations of the deposited films were performed in a standard very aggressive acidic solution (aerated 1N H2SO4 at 25 deg. C up to 168 h of immersion time) by means of direct current method (Tafel curves) and electrochemical impedance spectroscopy (EIS). The Rutherford backscattering spectroscopy (RBS) indicated that the films are very pure with the correct Al2O3 stoichiometry, while the IR absorption spectra showed that the films did not contain any -O-H groups. The surface film morphology was investigated by atomic force microscopy (AFM) and displayed a globular texture. The films were very smooth, with a maximum root mean square roughness, for example, of 14 nm for a 0.96 μm thick coating. The EIS data confirmed, as expected, that a 2.40 μm Al2O3 layer ensures the best corrosion protection after 168 h of immersion in the very acidic environment used

  3. 镁合金防腐涂层的研究%Research on Anticorrosive Coating of Magnesium Alloy

    Institute of Scientific and Technical Information of China (English)

    张云露; 张士卫; 蔺绍玲

    2014-01-01

    To solve the corrosion of magnesium alloy in the engineering application,the paper imitated the working con-dition,made magnesium alloy parts,and prepared micro-arc oxidation layers and micro-arc oxidation electrophoresis layers on the parts.Salt spray tests and static load tests showed that micro-arc oxidation layers can protect magnesium alloy from corroding on the condition that micro-arc oxidation layer is unbroken,but on normal working condition,it is inevitable to keep micro-arc oxidation layers unbroken.Preparing organic coating on the micro-arc oxidation electrophoresis layers can not only protect micro-arc oxidation layer from destruction,but also can protect magnesium alloy from corroding.%为解决镁合金在工程应用过程中的腐蚀问题,按照工况条件制作了镁合金试验件,并在试验件上分别制备了微弧氧化电泳层和微弧氧化电泳有机涂层。通过试样的盐雾试验和静载试验,得出下述结论:微弧氧化电泳层在不被破坏的前提下,可以保护镁合金不受腐蚀;但在工况条件下,由于过盈配合等原因,不可避免地会破坏微弧电泳层,导致镁合金腐蚀。研究表明,在微弧氧化电泳层上制备有机涂层,既能有效保证微弧氧化电泳层不被破坏,又可在实际工况条件下保护镁合金不受腐蚀。

  4. 重防腐涂料用水性环氧乳液的制备%Preparation of waterborne epoxy emulsion for heavy-duty anticorrosion coating

    Institute of Scientific and Technical Information of China (English)

    陈中华; 高菲菲; 穆爱婷

    2012-01-01

    A specified nonionic emulsifier for waterborne epoxy resin was prepared by reaction between high-molecular weight polyether and solid bisphenoi A epoxy resin, and then used to prepare waterborne epoxy emulsion by phase inversion technique. The effect of the dosage of boron trifluoride (BF3) diethyl etherate as catalyst on the epoxy value of the reaction system with epoxy resin CYD011 and polyethylene glycol PEG6000 was discussed. The structure of emulsifier was characterized by infrared spectroscopy and gel permeation chromatography. The molar ratio of epoxy resin to PEG6000, mass fraction of emulsifier, emulsification temperature, and epoxy resins with various molecular weight on the performance of epoxy emulsion were studied. The results showed that a highly-stable emulsion with particlesize <1 um can be obtained when the epoxy equivalent of epoxy resin is 450-500, emulsification temperature is 75℃, the dosage of catalyst is 0.40%, the molar ratio of epoxy resin to PEG6000 is 1:1, and the mass fraction of emulsifier is 15wt%. The film prepared from the emulsion features a flexibility of 1 mm and an impact strength of 50 kg-cm, and is able to endure corrosion in 5wt% NaCl solution for 17 d and salt spray test for 480 h. The emulsion can be applied to heavy- duty anticorrosion coating.%采用固体双酚A型环氧树脂与高分子量聚醚反应合成水性环氧树脂专用非离子型乳化剂,然后结合相反转技术制备水性环氧乳液.讨论了催化剂三氟化硼乙醚(BF3-乙醚)的用量对环氧树脂CYD011和聚乙二醇PEG6000反应体系环氧值的影响,并利用红外光谱和凝胶渗透色谱对合成乳化剂的结构进行表征,探讨了环氧树脂与PEG6000的摩尔比、乳化剂质量分数、乳化温度及不同分子量的环氧树脂对乳液性能的影响.结果表明,当环氧树脂的环氧当量为450 ~ 500,乳化温度为75℃、催化剂用量为0.40%、n(环氧树脂):n(PEG6000)=1:1、乳化剂质量分数为15

  5. Corrosion and anticorrosion. Industrial practice

    International Nuclear Information System (INIS)

    This book comprises 14 chapters written with the collaboration of about 50 French experts of corrosion. It is complementary to another volume entitled 'corrosion of metals and alloys' and published by the same editor. This volume comprises two parts: part 1 presents the basic notions of corrosion phenomena, the properties of surfaces, the electrochemical properties of corrosion etc.. Part 2 describes the most frequent forms of corrosion encountered in industrial environments and corresponding to specific problems of protection: marine environment, atmospheric corrosion, galvanic corrosion, tribo-corrosion, stress corrosion etc.. The first 8 chapters (part 1) treat of the corrosion problems encountered in different industries and processes: oil and gas production, chemical industry, phosphoric acid industry, PWR-type power plants, corrosion of automobile vehicles, civil engineering and buildings, corrosion of biomaterials, non-destructive testing for the monitoring of corrosion. The other chapters (part 2) deal with anticorrosion and protective coatings and means: choice of materials, coatings and surface treatments, thick organic coatings and enamels, paints, corrosion inhibitors and cathodic protection. (J.S.)

  6. Synthesize and characterization of a novel anticorrosive cobalt ferrite nanoparticles dispersed in silica matrix (CoFe2O4-SiO2) to improve the corrosion protection performance of epoxy coating

    Science.gov (United States)

    Gharagozlou, M.; Ramezanzadeh, B.; Baradaran, Z.

    2016-07-01

    This study aimed at studying the effect of an anticorrosive nickel ferrite nanoparticle dispersed in silica matrix (NiFe2O4-SiO2) on the corrosion protection properties of steel substrate. NiFe2O4 and NiFe2O4-SiO2 nanopigments were synthesized and then characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and transmission electron microscope (TEM). Then, 1 wt.% of nanopigments was dispersed in an epoxy coating and the resultant nanocomposites were applied on the steel substrates. The corrosion inhibition effects of nanopigments were tested by an electrochemical impedance spectroscopy (EIS) and salt spray test. Results revealed that dispersing nickel ferrite nanoparticles in a silica matrix (NiFe2O4-SiO2) resulted in the enhancement of the nanopigment dispersion in the epoxy coating matrix. Inclusion of 1 wt.% of NiFe2O4-SiO2 nanopigment into the epoxy coating enhanced its corrosion protection properties before and after scratching.

  7. Anti-corrosion properties of Ni-P alloy coated on engine cylinder prepared from jet electrodeposion%发动机气缸电喷镀镍磷合金镀层及耐腐蚀性能

    Institute of Scientific and Technical Information of China (English)

    王颖; 康敏; 傅秀清; 王兴盛

    2014-01-01

    Cylinder is the important part of tractor engine, which service life and the production cost are directly affected by anti-corrosion of the component. With the excellent wear resistance, corrosion resistance and higher hardness, Ni-P alloy deposited layer plays an important role for enhance the service life and reliability of cylinder, and the capability and quality of the tractor engine can be improved. Because of severe working environment of cylinder and piston such as high temperature, high load, high-velocity motion, poor lubrication, difficult cooling, especially weak acid for work environment, it is advisable to study the anti-corrosion properties of Ni-P alloy coated on engine cylinder. However, with the advancement of social economy, the conventional method for electrodeposited Ni-P alloy fails to meet the requirements of the development due to lower depositing rate and lower production efficiency. The jet electrodeposition is developed in recent years, which can significant increase the production efficiency because jet electrolyte can accelerate transfer process of the electrodeposition material and augment limiting current density. So the jet electrodeposition is a kind of high-velocity, selective electrodeposition technique with high deposition current density. In this paper, the engine cylinder coated with Ni-P alloy with jet electrodeposition was taken as research object. The surface appearance of deposited layer was observed by 6XB-PC reflective optical microscope. The corrosion behavior of Ni-P alloy coated on cylinder in 50 g/L NaCl solutions at different moment was studied by electrochemical impedance spectroscopy and potentiodynamic polarization method. The results show that the coating surface appearance is dense and smooth. Electrochemical impedance spectroscopy is composed of high and low frequency arcs when the layer immersed in 50 g/L NaCl solutions with 0.5, 1, 6, 12 and 24 h. The high frequency arcs have relation with original oxidation

  8. Sol-gel composite coatings as anti-corrosion barrier for structural materials of lead-bismuth eutectic cooled fast reactor

    Science.gov (United States)

    Kasada, Ryuta; Dou, Peng

    2013-09-01

    In order to protect the structural components of lead-bismuth eutectic (LBE) cooled fast breeder reactors (FBRs) from liquid metal corrosion, advanced aluminum-yttrium nano- and micro-composite coatings were developed using an improved sol-gel process, which includes dipping specimens in a Y-added sol-gel solution dispersed with ultrafine α-Al2O3 powders prepared by mechanical milling. Scanning electron microscopy (SEM) and field emission electron probe microprobe analyzer (FE-EPMA) analyses revealed that the coatings are composed of alumina with high density. Accelerated corrosion tests were conducted on coated specimens in liquid LBE at 650 °C under dynamic conditions. After the corrosion tests, no cracking, spallation, erosion and liquid metal (e.g., lead) penetration occurred to the coatings, indicating that the coatings possess an enhanced dynamic LBE corrosion resistance. The superior LBE corrosion resistance is due to the presence of the nano-structured composite particles integrated into the coatings and the addition of trace amount of yttrium. Severe erosion and penetration of liquid Pb occurred to the Al2O3 nano- and micro-composite coatings. After the corrosion tests, no cracking, spallation, erosion and liquid metal (e.g., lead) penetration occurred to the newly-developed aluminum-yttrium nano- and micro-composite coatings, indicating that the coatings possess an enhanced dynamic LBE corrosion resistance. Therefore we can conclude that the coatings possess an enhanced dynamic LBE corrosion resistance under the experimental conditions chosen here. It is a way to protect the structural materials of LBE cooled FBRs from liquid metal corrosion. The much improved corrosion resistance of aluminum-yttrium nano- and micro-composite coatings, relative to Al2O3 nano- and micro-composite coatings, is due to the much higher density and the significantly superior high temperature strength resulting from using of finer Al2O3 seeding particles and adding trace

  9. Sol–gel composite coatings as anti-corrosion barrier for structural materials of lead–bismuth eutectic cooled fast reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kasada, Ryuta, E-mail: r-kasada@iae.kyoto-u.ac.jp; Dou, Peng, E-mail: pengdou11@gmail.com

    2013-09-15

    In order to protect the structural components of lead–bismuth eutectic (LBE) cooled fast breeder reactors (FBRs) from liquid metal corrosion, advanced aluminum–yttrium nano- and micro-composite coatings were developed using an improved sol–gel process, which includes dipping specimens in a Y-added sol–gel solution dispersed with ultrafine α-Al{sub 2}O{sub 3} powders prepared by mechanical milling. Scanning electron microscopy (SEM) and field emission electron probe microprobe analyzer (FE-EPMA) analyses revealed that the coatings are composed of alumina with high density. Accelerated corrosion tests were conducted on coated specimens in liquid LBE at 650 °C under dynamic conditions. After the corrosion tests, no cracking, spallation, erosion and liquid metal (e.g., lead) penetration occurred to the coatings, indicating that the coatings possess an enhanced dynamic LBE corrosion resistance. The superior LBE corrosion resistance is due to the presence of the nano-structured composite particles integrated into the coatings and the addition of trace amount of yttrium.

  10. Sol–gel composite coatings as anti-corrosion barrier for structural materials of lead–bismuth eutectic cooled fast reactor

    International Nuclear Information System (INIS)

    In order to protect the structural components of lead–bismuth eutectic (LBE) cooled fast breeder reactors (FBRs) from liquid metal corrosion, advanced aluminum–yttrium nano- and micro-composite coatings were developed using an improved sol–gel process, which includes dipping specimens in a Y-added sol–gel solution dispersed with ultrafine α-Al2O3 powders prepared by mechanical milling. Scanning electron microscopy (SEM) and field emission electron probe microprobe analyzer (FE-EPMA) analyses revealed that the coatings are composed of alumina with high density. Accelerated corrosion tests were conducted on coated specimens in liquid LBE at 650 °C under dynamic conditions. After the corrosion tests, no cracking, spallation, erosion and liquid metal (e.g., lead) penetration occurred to the coatings, indicating that the coatings possess an enhanced dynamic LBE corrosion resistance. The superior LBE corrosion resistance is due to the presence of the nano-structured composite particles integrated into the coatings and the addition of trace amount of yttrium

  11. Anticorrosion and halobios control for tidal power generating units

    International Nuclear Information System (INIS)

    The anticorrosion and halobios control is the key techniquesrelated to the safety and durability of tidal power generating units. The technique of material application, antifouling coating and cathodic protection are often adopted. The technical research, application, updating and development are carried on Jiangxia Tidal Power Station, which is based on the old Unit 1-Unit 5 operated for nearly 30 years, and the new Unit 6 operated in 2007. It is found that stainless steeland the antifouling coating used in Unit 1- Unit 5 are very effective, but cathodic protection is often likely to fail because of the limitation of structure and installation. Analyses and studies for anticorrosion and halobios control techniques of tidal power generating units according to theory, experience and actual effects have been done, which can be for reference to the tidal power station designers and builders.

  12. Sol-gel composite coatings as anti-corrosion barrier for structural materials of lead-bismuth eutectic cooled fast reactor

    International Nuclear Information System (INIS)

    The lead-bismuth eutectic (LBE) cooled fast reactor as one of the next generation fission nuclear power systems requires the development of new high-temperature corrosion-resistant materials and systems against LBE. The sol-gel coating methodology has several advantages between other coating methodologies; low-temperature processing, complex oxide coating, and commercially-feasible cost. The present paper demonstrates superior corrosion resistance of modified sol-gel alumina coatings on structural materials against the LBE environments. Sol-gel solution was fabricated from Al(NO3)3·9H2O water solution with and without small amount of Y(NO3)3·6H2O. The ph value of solution was controlled by the addition of NH4OH. The nano-sized α-Al203 powders as a seeding were added into the solution. The resulting solution was then dip-deposited onto substrates, and calcined at 400 C in air. This process was repeated for several times to obtain thick (∼10 μm) coating. The substrate used was Inconel 600 because the Ni based alloys are highly susceptible for LBE corrosion. The coatings obtained were examined in LBE at temperatures of 500 to 650 C up to 100 hr s. The coated specimens were rotated up to 500 rpm in the melted LBE located in an Ar environment glove box. After the corrosion tests, the specimens were investigated by scanning electron microscopy with X-ray spectroscopy. LBE corrosion experiment at 500 C up to 100 hr s showed no change in the substrate and coatings. However increasing the LBE temperature up to 650 C resulted in the severe corrosion of substrates and coating made of Al(NO3)3·9H2O solution. On the other hand, the coating made of Al(NO3)3·9H2O and Y(NO3)3·6H2O solution showed excellent resistance and prevented the corrosion of substrate. (Author)

  13. Ceramic nanotubes for polymer composites with stable anticorrosion properties

    Science.gov (United States)

    Fakhrullin, R. F.; Tursunbayeva, A.; Portnov, V. S.; L'vov, Yu. M.

    2014-12-01

    The use of natural halloysite clay tubes 50 nm in diameter as nanocontainers for loading, storing, and slowly releasing organic corrosion inhibitors is described. Loaded nanotubes can be mixed well with many polymers and dyes in amounts of 5-10 wt % to form a ceramic framework (which increases the strength of halloysite composites by 30-50%), increase the adhesion of these coatings to metals, and allow for the slow release of corrosion inhibitors in defects of coatings. A significant improvement of protective anticorrosion properties of polyacryl and polyurethane coatings containing ceramic nanotubes loaded with benzotriazole and hydroxyquinoline is demonstrated.

  14. The implementation and application of chemical cleaning and anti-corrosive coating of the condenser%凝汽器化学清洗及防腐镀膜的实施及应用

    Institute of Scientific and Technical Information of China (English)

    田红艳

    2011-01-01

    影响发电机组安全运行的因素有很多,凝汽器铜管的腐蚀就是其中之一。凝汽器铜管一旦发生腐蚀泄漏,冷却水便会漏入凝结水中,从而导致锅炉、汽轮机等设备的腐蚀与结垢。对凝汽器铜管进行化学清洗及防腐镀膜,可以有效阻止或缓解各类腐蚀,延长凝汽器使用寿命,减少因铜管泄漏造成的紧急停机、凝结水浪费、锅炉结垢,避免设备提前更换、甚至安全事故等风险。大大延长铜管的使用寿命,有利于凝汽器安全经济运行。%There are many factors in influencing the safe operation of the generator, and corrosion of the condenser copper pipe is one of them. Once the corrosion and leakage of the condenser copper pipe happened, it will lead to cooling water leak into the condensed water, and the corrosion and fouling of boiler and turbine was thereby produced. If the condenser copper pipe were dealt with the chemical cleaning and anti-corrosive coating, some risks will be reduced. Then kinds of corrosion can be effectively prevented or alleviated, service life of the condenser can be prolonged, emergency stop, condensed water waste and boiler scale caused by copper tube leakage will be reduced, replacement of the equipments in early, even accidents will avoid. Greatly extend the service life of the copper pipe will benefit to the safe and economical operation of the condenser.

  15. Smart Mesoporous Silica Nanocapsules as Environmentally Friendly Anticorrosive Pigments

    Directory of Open Access Journals (Sweden)

    C. Zea

    2015-01-01

    Full Text Available Nowadays there is a special interest to study and develop new smart anticorrosive pigments in order to increase the protection life time of organic coatings and, simultaneously, to find alternatives to conventional toxic and carcinogenic hexavalent chromium compounds. In this respect, the great development of nanotechnologies in recent years has opened up a range of possibilities in the field of anticorrosive paints through the integration of encapsulated nanoscale containers loaded with active components into coatings. By means of a suitable design of the capsule, the release of the encapsulated corrosion inhibitor can be triggered by different external or internal factors (pH change, mechanical damage, etc. thus preventing spontaneous leakage of the active component and achieving more efficient and economical use of the inhibitor, which is only released upon demand in the affected area. In the present work, the improved anticorrosive behaviour achieved by encapsulated mesoporous silica nanocontainers filled with an environmentally friendly corrosion inhibitor has been evaluated. It has been proven that a change in the pH allows the rupture of the capsules, the release of the inhibitor, and the successful protection of the carbon steel substrate.

  16. Comparatively electrochemical studies at different operational temperatures for the effect of layered silicate and spherical silica on the anticorrosion efficiency of PANI nanocomposite coatings.

    Science.gov (United States)

    Chang, Kung-Chin; Lai, Mei-Chun; Peng, Chih-Wei; Huang, Hsin-Hua; Fan, Tsuny-Hua; Yeh, Jui-Ming; Chou, Yi-Chen

    2011-02-01

    In this paper, a series of PANI nanocomposites have been successfully prepared by in situ oxidative polymerization. The as-prepared PANI nanocomposites were subsequently characterized by WAXRD patterns and TEM. It should be noted that the nanocomposite coating containing 3 wt-% of organophilic clay loading was found to exhibit an observable enhanced corrosion protection on cold-rolled steel (CRS) electrode at higher operational temperature of 50 degrees C, which was even better than that of uncoated and electrode-coated with PANI or PANI nanocomposites with 3 wt-% of amino-modified silica nanoparticles alone at room temperature of 30 degrees C based on the electrochemical parameter evaluations (e.g., E(corr), R(p), I(corr), R(corr) and impedance). The vapor permeability property at three different operational temperatures of PANI and PANI nanocomposite membranes were investigated by vapor permeability analyzer (VPA). Effect of material composition on the molecular weight, optical properties and surface hydrophobicity of neat PANI and PANI nanocomposite, in the form of membrane and solution, were studied by gel permeation chromatography (GPC), ultraviolet-visible absorption spectra and contact-angle measurements, respectively. Finally, electrical conductivity at three different operational temperatures of PANI and PANI nanocomposite powder-pressed pellets was also investigated through the measurements of standard four-point-probe technique. PMID:21456149

  17. Graphene grown on stainless steel as a high-performance and ecofriendly anti-corrosion coating for polymer electrolyte membrane fuel cell bipolar plates

    Science.gov (United States)

    Pu, Nen-Wen; Shi, Gia-Nan; Liu, Yih-Ming; Sun, Xueliang; Chang, Jeng-Kuei; Sun, Chia-Liang; Ger, Ming-Der; Chen, Chun-Yu; Wang, Po-Chiang; Peng, You-Yu; Wu, Chia-Hung; Lawes, Stephen

    2015-05-01

    In this study, the growth of graphene by chemical vapor deposition (CVD) on SUS304 stainless steel and on a catalyzing Ni/SUS304 double-layered structure was investigated. The results indicated that a thin and multilayered graphene film can be continuously grown across the metal grain boundaries of the Ni/SUS304 stainless steel and significantly enhance its corrosion resistance. A 3.5 wt% saline polarization test demonstrated that the corrosion currents in graphene-covered SUS304 were improved fivefold relative to the corrosion currents in non-graphene-covered SUS304. In addition to enhancing the corrosion resistance of stainless steel, a graphene coating also ameliorates another shortcoming of stainless steel in a corrosive environment: the formation of a passive oxidation layer on the stainless steel surface that decreases conductivity. After a corrosion test, the graphene-covered stainless steel continued to exhibit not only an excellent low interfacial contact resistance (ICR) of 36 mΩ cm2 but also outstanding drainage characteristics. The above results suggest that an extremely thin, lightweight protective coating of graphene on stainless steel can act as the next-generation bipolar plates of fuel cells.

  18. Influence on the anticorrosive properties of the use of erbium (III) trifluoromethanesulfonate as initiator in an epoxy powder clearcoat

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, S.J. [Centro de Biomateriales, Universitat Politecnica de Valencia, Camino de Vera s/n, E-46071 Valencia (Spain)]. E-mail: sangares@upvnet.upv.es; Suay, J. [Centro de Biomateriales, Universitat Politecnica de Valencia, Camino de Vera s/n, E-46071 Valencia (Spain)

    2007-08-15

    New low curing temperature epoxy powder coatings cured cationically by the use of erbium (III) trifluoromethanesulfonate as initiator have been formulated. Their curing kinetics and anticorrosive properties have been studied and compared with a system commonly used in industry (o-tolylbiguanide/epoxy resin). Three different tests of anticorrosive properties (EIS, AC/DC/AC, and salt fog spray) have been used together with an adherence test, in order to establish the optimal system. Results show that a system employing 1 phr of erbium triflate presents good anticorrosive properties. The technique AC/DC/AC has shown its ability to evaluate properly, much faster, and in accordance to anticorrosive properties results' of powder coatings obtained by other techniques.

  19. Experimental Study on the Electrochemical Anti-Corrosion Properties of Steel Structures Applying the Arc Thermal Metal Spraying Method

    OpenAIRE

    Hong-Bok Choe; Han-Seung Lee; Jun-Ho Shin

    2014-01-01

    The arc thermal metal spraying method (ATMSM) provides proven long-term protective coating systems using zinc, aluminum and their alloys for steel work in a marine environment. This paper focuses on studying experimentally the anti-corrosion criteria of ATMSM on steel specimens. The effects of the types of spraying metal and the presence or absence of sealing treatment from the thermal spraying of film on the anti-corrosion performance of TMSM were quantitatively evaluated by electrochemical ...

  20. Characterization of micro- and nanocapsules for self-healing anti-corrosion coatings by high-resolution SEM with coupled transmission mode and EDX.

    Science.gov (United States)

    Hodoroaba, V-D; Akcakayiran, D; Grigoriev, D O; Shchukin, D G

    2014-04-21

    The observation of morphological details down to the nanometer range of the outer surface of micro-, submicro- and nanoparticles in a high-resolution scanning electron microscope (SEM) was extended with in-depth observation by enabling the transmission mode in the SEM, i.e. TSEM. The micro- and nanocapsules characterized in this study were fabricated as depots for protective agents to be embedded in innovative self-healing coatings. By combining the two imaging modes (upper and in-depth observation) complementing each other a better characterisation by a more comprehensive interpretation of the "consistency" of the challenging specimens, e.g. including details "hidden" beyond the surface or the real specimen shape at all, has been attained. Furthermore, the preparation of the quasi electron transparent samples onto thin supporting foils enables also elemental imaging by energy dispersive X-ray spectroscopy (EDX) with high spatial resolution. Valuable information on the elemental distribution in individual micro-, submicro- and even nanocapsules completes the "3D" high resolution morphological characterization at the same multimodal SEM/TSEM/EDX system. PMID:24605359

  1. 无溶剂环氧重防腐隔热导静电涂料的研制%Preparation of Solventless Epoxy Heavy Anti-corrosion Insulation Conducting Electrostatic Coating

    Institute of Scientific and Technical Information of China (English)

    刘成楼; 隗功祥

    2012-01-01

    以丙烯酸改性环氧树脂为基料,以反应型和非反应型稀释剂为溶剂、以液态聚硫橡胶为增韧剂,在功能颜填料和助剂的配合下制备成甲组分;以腰果壳液合成的改性胺为固化剂,在促进剂和亲水剂配合下组成乙组分。固化后的涂层柔韧、致密,具有重防腐、隔热隔音、导静电性能。%Component I was prepared by using acrylic modified epoxy resin used as binder and reactive and nonreactive diluents as solvent, liquid polysulfide rubber as toughening agents, functional pigments and extender and additives; component Ⅱ was prepared by using modified amine synthesized by cashew nut shell liquid as curing agent, assorted with promoting agents and hydrophilic agent. After curing, the film flexible and compact, with heavy anti-corrosion, heat insulation, sound insulation, conducting electrostatic properties.

  2. Low-Temperature in Situ Growth of Graphene on Metallic Substrates and Its Application in Anticorrosion.

    Science.gov (United States)

    Zhu, Minmin; Du, Zehui; Yin, Zongyou; Zhou, Wenwen; Liu, Zhengdong; Tsang, Siu Hon; Teo, Edwin Hang Tong

    2016-01-13

    Metal or alloy corrosion brings about huge economic cost annually, which is becoming one area of growing concern in various industries, being in bulk state or nanoscale range. Here, single layer or few layers of graphene are deposited on various metallic substrates directly at a low temperature down to 400 °C. These substrates can be varied from hundreds-micrometer bulk metallic or alloy foils to tens of nanometer nanofibers (NFs). Corrosion analysis reveals that both graphene-grown steel sheets and NFs have reduced the corrosion rate of up to ten times lower than that of their bare corresponding counterparts. Moreover, such low-temperature in situ growth of graphene demonstrates stable and long-lasting anticorrosion after long-term immersion. This new class of graphene coated nanomaterials shows high potentials in anticorrosion applications for submarines, oil tankers/pipelines, and ruggedized electronics. PMID:26683895

  3. Test Production of Anti-Corrosive Paint in Laboratory Scale

    International Nuclear Information System (INIS)

    The main purpose of this project is to produce the anti-corrosive paint in laboratory scale. In these experiments, local raw materials, natural resin (shellac), pine oil, turpentine and ethyl alcohol wer applied basically. Laboratory trials were undrtaken to determine the suitablity of raw materials ane their composition for anti-corrosive paint manufacture.The results obtained show that the anti-corrosive paint from experiment No.(30) is suitable for steel plate and this is also considered commercially economics

  4. Study on the anticorrosion, biocompatibility, and osteoinductivity of tantalum decorated with tantalum oxide nanotube array films.

    Science.gov (United States)

    Wang, Na; Li, Hongyi; Wang, Jinshu; Chen, Su; Ma, Yuanping; Zhang, Zhenting

    2012-09-26

    With its excellent anticorrosion and biocompatibility, tantalum, as a promising endosseous implant or implant coating, is attracting more and more attention. For improving physicochemical property and biocompatibility, the research of tantalum surface modification has increased. Tantalum oxide (Ta(2)O(5)) nanotube films can be produced on tantalum by controlling the conditions of anodization and annealing. The objective of our present study was to investigate the influence of Ta(2)O(5) nanotube films on pure tantalum properties related with anticorrosion, protein adsorption, and biological function of rabbit bone mesenchymal stem cells (rBMSCs). The polarization curve was measured, the adsorption of bovine serum albumin and fibronectin to Ta(2)O(5) nanotubes was detected, and the morphology and actin cytoskeletons of the rBMSCs were observed via fluorescence microscopy, and the adhesion and proliferation of the rBMSCs, as well as the osteogenic differentiation potential on tantalum specimens, were examined quantificationally by MTT and real-time PCR technology. The results showed that Ta(2)O(5) nanotube films have high anticorrosion capability and can increase the protein adsorption to tantalum and promote the adhesion, proliferation, and differentiation of rBMSCs, as well as the mRNA expression of osteogenic gene such as Osterix, ALP, Collagen-I, and Osteocalcin on tantalum. This study suggests that Ta(2)O(5) nanotube films can improve the anticorrosion, biocompatibility, and osteoinduction of pure tantalum, which provides the theoretical elaboration for development of tantalum endosseous implant or implant coating to a certain extent. PMID:22894817

  5. 镁合金表面热喷涂铝的防腐蚀研究%Study on Anti-corrosion of Al Coating Prepared by Thermal Spray on Mg Alloy Surface

    Institute of Scientific and Technical Information of China (English)

    常森; 张宝红; 徐宏妍

    2011-01-01

    通过电化学实验和浸泡实验,研究不同压缩量状态下AZ80镁合金热喷涂铝涂层的抗腐蚀性能.结果表明:热喷涂铝涂层可明显提高AZ80镁合金的抗腐蚀性能,且当热喷涂铝涂层的压缩量为60%时,热喷涂铝涂层的抗腐蚀性能最好.%The corrosion resistance of thermal sprayed aluminum coating on AZ80 magnesium alloy with different corpression state was studied through immersion and electrochemical test. The results show that corrosion resistance of thermal sprayed aluminum coating on AZ80 magnesium alloy can be significantly improved, and when the compression of thermal spray coating is 60%, the corrosion resistance of the thermal spray coating is best.

  6. Special methods of anti-corrosion treatment in heat exchangers

    International Nuclear Information System (INIS)

    An anti-corrosion treatment must be adapted to the design of the heat exchanger and the conditions under which it is used. It is often the case, therefore, that highly specialized solutions are found. For the tubular heat exchanger, an organic coating has frequently proved suitable. The results obtained are determined by the construction, the surface characteristics of the components and paying attention to the risk of blister formation. With water-cooled condensers, cleaning of the tubes while the equipment is running has proved successful. It alleviates the corrosion problem and assists the action of the inhibitors. Equipment made from materials such as titanium and austenitic CrNi steels, which are capable of being passivated, can frequently be retained in a passive state by adding air to the corrosive medium. In such cases, the excessive corrosion would normally necessitate the use of an expensive material. Where damage is caused by gaps and dead spaces it is not always possible to find a constructional remedy. A well-devised construction can subsequently be decisively influenced by manufacturing techniques relating to the structure, the state of internal stress or the surface condition. (orig./GSCH)

  7. A room temperature cured sol-gel anticorrosion pre-treatment for Al 2024-T3 alloys

    International Nuclear Information System (INIS)

    The inherent reactivity of the Al-Cu alloys is such that their use for structural, marine, and aerospace components and structures would not be possible without prior application of a corrosion protection system. Historically these corrosion protection systems have been based upon the use of chemicals containing Cr(VI) compounds. Organic-inorganic hybrid silane coatings are of increasing interest in industry due to their potential application for the replacement of current toxic hexavalent chromate based treatments. In the present study, a hybrid epoxy-silica-alumina coating with or without doped cerium nitrate has been prepared using a sol-gel method. The hybrid coatings were applied by a dip-technique to an Al-Cu alloy, Al 2024-T3, and subsequently cured at room temperature. The anticorrosion properties of the coatings within 3.5% NaCl were studied using electrochemical impedance spectroscopy (EIS), and conventional DC polarisation. An exfoliation test method involving immersion in a solution of 4 M NaCl, 0.5 M KNO3 and 0.1 M HNO3 was also used. The cerium nitrate doped sol-gel coating exhibited excellent anticorrosion properties providing an adherent protection film on the Al 2024-T3 substrate. The resistance to corrosion of the sol-gel coating was also evaluated by analysing the morphology of the coating before and after corrosion testing using scanning electron microscopy

  8. Impact of heat treatment on surface chemistry of Al-coated Eurofer for application as anti-corrosion and T-permeation barriers in a flowing Pb–15.7Li environment

    International Nuclear Information System (INIS)

    Highlights: ► Electro-chemical Al deposition is industrially relevant for barrier formation. ► Al scales have to be converted into protective layers by heat treatments. ► Morphology of scales depend on deposition parameters. ► Solid state diffusion step at 640 °C avoids critical Al melting and activates steel surface. ► Al2O3 protective scales detected. - Abstract: The compatibility testing of Eurofer steel in flowing Pb–15.7Li has shown that corrosion attack is a serious concern at least under view of precipitate formation from dissolved steel components in cooler system sections, leading to a high risk of tube blockages. Additionally, the T-permeation from the liquid breeder through the steel structure into the He-cooling system is an important safety issue. Both topics may be reduced by the application of barriers. Hot dip aluminization (HDA) showed that Al scales exhibit such ability but claimed also the development of improved coating technologies. Thus, two electro-chemically-based deposition processes, which exhibit industrial relevance and adjustable layer thickness of deposited Al, were developed, tested and characterized. Both are working with water-free electrolytes of toluene or ionic liquid (IL) base near room temperature (RT). The successfully deposited homogeneous layers need a heat treatment to establish the required protective/functional properties. During this stage, the Al reacts with the steel and forms an Al-enriched zone with a thin protective Al2O3 surface scale. However, the topology is rough and pores are visible. Thus, for optimization of surface structure and scale quality, investigations concerning the required heat treatment were performed including effects coming from the applied coating technology.

  9. Impact of heat treatment on surface chemistry of Al-coated Eurofer for application as anti-corrosion and T-permeation barriers in a flowing Pb-15.7Li environment

    Energy Technology Data Exchange (ETDEWEB)

    Konys, J., E-mail: juergen.konys@kit.edu [Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen (Germany); Krauss, W.; Holstein, N.; Lorenz, J.; Wulf, S. [Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen (Germany); Bhanumurthy, K. [Scientific Information Resource Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)

    2012-08-15

    Highlights: Black-Right-Pointing-Pointer Electro-chemical Al deposition is industrially relevant for barrier formation. Black-Right-Pointing-Pointer Al scales have to be converted into protective layers by heat treatments. Black-Right-Pointing-Pointer Morphology of scales depend on deposition parameters. Black-Right-Pointing-Pointer Solid state diffusion step at 640 Degree-Sign C avoids critical Al melting and activates steel surface. Black-Right-Pointing-Pointer Al{sub 2}O{sub 3} protective scales detected. - Abstract: The compatibility testing of Eurofer steel in flowing Pb-15.7Li has shown that corrosion attack is a serious concern at least under view of precipitate formation from dissolved steel components in cooler system sections, leading to a high risk of tube blockages. Additionally, the T-permeation from the liquid breeder through the steel structure into the He-cooling system is an important safety issue. Both topics may be reduced by the application of barriers. Hot dip aluminization (HDA) showed that Al scales exhibit such ability but claimed also the development of improved coating technologies. Thus, two electro-chemically-based deposition processes, which exhibit industrial relevance and adjustable layer thickness of deposited Al, were developed, tested and characterized. Both are working with water-free electrolytes of toluene or ionic liquid (IL) base near room temperature (RT). The successfully deposited homogeneous layers need a heat treatment to establish the required protective/functional properties. During this stage, the Al reacts with the steel and forms an Al-enriched zone with a thin protective Al{sub 2}O{sub 3} surface scale. However, the topology is rough and pores are visible. Thus, for optimization of surface structure and scale quality, investigations concerning the required heat treatment were performed including effects coming from the applied coating technology.

  10. Experimental Study on the Electrochemical Anti-Corrosion Properties of Steel Structures Applying the Arc Thermal Metal Spraying Method

    Directory of Open Access Journals (Sweden)

    Hong-Bok Choe

    2014-12-01

    Full Text Available The arc thermal metal spraying method (ATMSM provides proven long-term protective coating systems using zinc, aluminum and their alloys for steel work in a marine environment. This paper focuses on studying experimentally the anti-corrosion criteria of ATMSM on steel specimens. The effects of the types of spraying metal and the presence or absence of sealing treatment from the thermal spraying of film on the anti-corrosion performance of TMSM were quantitatively evaluated by electrochemical techniques. The results showed that ATMSM represented a sufficient corrosion resistance with the driving force based on the potential difference of more than approximately 0.60 V between the thermal spraying layer and the base substrate steel. Furthermore, it was found that the sealing treatment of specimens had suppressed the dissolution of metals, increased the corrosion potential, decreased the corrosion current density and increased the polarization resistance. Metal alloy Al–Mg (95%:5% by mass with epoxy sealing coating led to the most successful anti-corrosion performance in these electrochemical experiments.

  11. Anti-corrosion measures and management of seawater system in Qinshan Nuclear Power Plant

    International Nuclear Information System (INIS)

    This paper introduces the process flow of seawater system in Qinshan Nuclear Power Plant and current anti-corrosion measures. It also introduces the policy, programs and procedures which are established for anti-corrosion management system. At last, this paper sets forth several anti-corrosion difficulties. (authors)

  12. Fabrication of anticorrosive multilayer onto magnesium alloy substrates via spin-assisted layer-by-layer technique

    Energy Technology Data Exchange (ETDEWEB)

    Cai Kaiyong, E-mail: Kaiyong_cai@cqu.edu.cn [Key Laboratory of Biorheological Science and Technology (Chongqing University), Ministry of Education, College of Bioengineering, Chongqing University, Chongqing 400044 (China); Sui Xiaojing; Hu Yan [Key Laboratory of Biorheological Science and Technology (Chongqing University), Ministry of Education, College of Bioengineering, Chongqing University, Chongqing 400044 (China); Zhao Li [China National Centre for Biotechnology Development, No. 16, Xi Si Huan Zhong Lu, Haidian District, Beijing 100036 (China); Lai Min; Luo Zhong; Liu Peng; Yang Weihu [Key Laboratory of Biorheological Science and Technology (Chongqing University), Ministry of Education, College of Bioengineering, Chongqing University, Chongqing 400044 (China)

    2011-12-01

    To improve the corrosion resistance of magnesium alloy, we reported a novel approach for the fabrication of anticorrosive multilayers onto AZ91D substrates. The multilayers were composed of poly(ethylene imine) (PEI), poly(styrene sulfonate) (PSS) and 8-hydroxyquinoline (8HQ). They were deposited onto AZ91D substrates via a spin-assisted layer-by-layer (LbL) technique. The multilayered structure was stabilized with glutaraldehyde (GA) as crossing linker. It was confirmed by Fourier transform infrared spectroscopy (FT-IR). Surface morphologies and elemental compositions of the formed anticorrosive multilayers were characterized with scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), respectively. The corrosion performance of the multilayer coated AZ91D substrates was characterized by hydrogen evolution. The results of electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization measurements suggested that the multilayered coating improved the corrosion resistance of AZ91D substrates. In vitro study revealed that the multilayered coating was cytocompatible. The study provides a potential alternative for the fabrication of corrosion resistant magnesium alloy-based implants. Highlights: {yields} Corrosion protective multilayers have been constructed onto AZ91D substrates via layer by layer technique. {yields} The multilayered structured containing 8-hydroxyquinoline highly improves the corrosion resistance of AZ91D substrates. {yields} The novel multilayered coating is potentially important for developing corrosion resistant magnesium alloy-based implants.

  13. Fabrication of anticorrosive multilayer onto magnesium alloy substrates via spin-assisted layer-by-layer technique

    International Nuclear Information System (INIS)

    To improve the corrosion resistance of magnesium alloy, we reported a novel approach for the fabrication of anticorrosive multilayers onto AZ91D substrates. The multilayers were composed of poly(ethylene imine) (PEI), poly(styrene sulfonate) (PSS) and 8-hydroxyquinoline (8HQ). They were deposited onto AZ91D substrates via a spin-assisted layer-by-layer (LbL) technique. The multilayered structure was stabilized with glutaraldehyde (GA) as crossing linker. It was confirmed by Fourier transform infrared spectroscopy (FT-IR). Surface morphologies and elemental compositions of the formed anticorrosive multilayers were characterized with scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), respectively. The corrosion performance of the multilayer coated AZ91D substrates was characterized by hydrogen evolution. The results of electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization measurements suggested that the multilayered coating improved the corrosion resistance of AZ91D substrates. In vitro study revealed that the multilayered coating was cytocompatible. The study provides a potential alternative for the fabrication of corrosion resistant magnesium alloy-based implants. Highlights: → Corrosion protective multilayers have been constructed onto AZ91D substrates via layer by layer technique. → The multilayered structured containing 8-hydroxyquinoline highly improves the corrosion resistance of AZ91D substrates. → The novel multilayered coating is potentially important for developing corrosion resistant magnesium alloy-based implants.

  14. Fly ash based zeolitic pigments for application in anticorrosive paints

    Science.gov (United States)

    Shaw, Ruchi; Tiwari, Sangeeta

    2016-04-01

    The purpose of this work is to evaluate the utilization of waste fly ash in anticorrosive paints. Zeolite NaY was synthesized from waste fly ash and subsequently modified by exchanging its nominal cation Na+ with Mg2+ and Ca2+ ions. The metal ion exchanged zeolite was then used as anticorrosive zeolitic pigments in paints. The prepared zeolite NaY was characterized using X-Ray diffraction technique and Scanning electron microscopy. The size, shape and density of the prepared fly ash based pigments were determined by various techniques. The paints were prepared by using fly ash based zeolitic pigments in epoxy resin and the percentages of pigments used in paints were 2% and 5%. These paints were applied to the mild steel panels and the anticorrosive properties of the pigments were assessed by the electrochemical spectroscopy technique (EIS).

  15. Studies on anticorrosion layers on steels typical for power stations

    International Nuclear Information System (INIS)

    Anticorrosion protective oxide layers arise on ferrous materials in the coolant circuits of power stations from the effect of hot water or steam. The corrosion damage occurring in practice starts with anticorrosion layer failure. However, the extent of corrosion inhibition also determines transfer of metallic compounds into the corrosive medium. The corrosion products transported by the medium form deposits hence leading to a reduction of heat transfer efficiency, local corrosion effects and, in pressurized water reactor circuits, radioactive contamination. Power plant chemistry requires a more detailed clarification of the processes involved at the phase boundary material/operating medium. This work is intended to give a contribution to those problems. (author)

  16. Coatings.

    Science.gov (United States)

    Anderson, Dennis G.

    1989-01-01

    This review covers analytical techniques applicable to the examination of coatings, raw materials, and substrates upon which coatings are placed. Techniques include chemical and electrochemical methods, chromatography, spectroscopy, thermal analysis, microscopy, and miscellaneous techniques. (MVL)

  17. Anticorrosion surface alloying of ferrous metal by carbide formers

    International Nuclear Information System (INIS)

    It is shown theoretically and experimentally that in cases of surface chromizing and titanizing of ferrous metal, proper carbon of the latter plays an important positive role, providing the formation of exclusively dense surface carbide layers with high and durable corrosion and mechanic stability. In the future surface alloying must become a more effective method of anticorrosion alloying

  18. Cold laminar galvanizing: a new anti-corrosion concept

    International Nuclear Information System (INIS)

    Cold laminar galvanizing, a recent anticorrosion technology, now combines the most positive characteristics of the hot galvanizing protective systems. This patented technology has a zinc laminated foil (obtained by processing 99.9% pure zinc ingots) that is homogeneous and isotropic, with a standard thickness of 80-100μm. This foil is backed with an electro-conductive, selfadhesive glue prepared under an original formula. The zinc laminated foil offers excellent anchorage and elevated resistance to the main atmospheric agents

  19. Al-based anti-corrosion and T-permeation barrier development for future DEMO blankets

    Energy Technology Data Exchange (ETDEWEB)

    Krauss, W., E-mail: wolfgang.krauss@kit.edu [Karlsruhe Institute of Technology, Hermann von Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Konys, J.; Holstein, N.; Zimmermann, H. [Karlsruhe Institute of Technology, Hermann von Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

    2011-10-01

    In the Helium-Cooled-Liquid-Lead (HCLL) design of Test-Blanket-Modules (TBM's) for a future fusion power plant Pb-15.7Li is used as liquid breeder which is in direct contact with the structure material, e.g. EUROFER steel. Compatibility testing showed that high corrosion attack appears and that the dissolved steel components form precipitates with a high risk of system blockages. A reliable operation needs coatings as corrosion barriers. The earlier developed Hot-Dip Aluminisation (HDA) process has shown that Al-based scales can act as anti-corrosion as well as T-permeation barriers. Meanwhile two advanced electro-chemically based processes for deposition of Al-scales were successfully developed. The first (ECA = Electro-Chemical Al-deposition) is working with an organic electrolyte and the second one (ECX = Electro-Chemical-X-metal-deposition) is based on ionic liquids. Coatings in the {mu}m-range were deposited homogeneously with exact controllable thicknesses. Metallurgical investigations showed the successful generation of protective scales and compatibility testing demonstrated the barrier function.

  20. Al-based anti-corrosion and T-permeation barrier development for future DEMO blankets

    Science.gov (United States)

    Krauss, W.; Konys, J.; Holstein, N.; Zimmermann, H.

    2011-10-01

    In the Helium-Cooled-Liquid-Lead (HCLL) design of Test-Blanket-Modules (TBM's) for a future fusion power plant Pb-15.7Li is used as liquid breeder which is in direct contact with the structure material, e.g. EUROFER steel. Compatibility testing showed that high corrosion attack appears and that the dissolved steel components form precipitates with a high risk of system blockages. A reliable operation needs coatings as corrosion barriers. The earlier developed Hot-Dip Aluminisation (HDA) process has shown that Al-based scales can act as anti-corrosion as well as T-permeation barriers. Meanwhile two advanced electro-chemically based processes for deposition of Al-scales were successfully developed. The first (ECA = Electro-Chemical Al-deposition) is working with an organic electrolyte and the second one (ECX = Electro-Chemical-X-metal-deposition) is based on ionic liquids. Coatings in the μm-range were deposited homogeneously with exact controllable thicknesses. Metallurgical investigations showed the successful generation of protective scales and compatibility testing demonstrated the barrier function.

  1. Microstructural studies of anti-corrosion Sn O2 thin films for glass protection

    International Nuclear Information System (INIS)

    .Advances in display technology, solar energy conversion and electrochemistry devices have simulated the study of transparent and electrically conductive coatings. In this context, Sn O2 is among the first transparent conductors that have received a significant commercialization. Moreover, owing to its chemical and thermal stability, Sn O2 thin coatings prepared by sol-gel method are promising candidates for glass anticorrosion applications. However, the two main challenges that we have to deal with are: - the elimination of the residual porosity of Sn O2 thin films. - the need of a non-aqueous sol for film deposition owing to the sensibility of the substrate to water corrosion. In this context, we first investigated two different ways to control the final porosity of the film, by acting on: Sn O2 particle formation: a complexing agent was added to the precursor solution in order to modify particle nucleation and growth during isothermal hydrolysis; and pore size growth: Sn O2 particles were doped with different amount of Mn or Sb, in order to increase the film densification during isothermal sintering. The kinetics of particles and pores formation processes were studied by in situ SAXS measurements. (author)

  2. Al-based anti-corrosion and T-permeation barrier development for future DEMO blankets

    International Nuclear Information System (INIS)

    In the Helium-Cooled-Liquid-Lead (HCLL) design of Test-Blanket-Modules (TBM's) for a future fusion power plant Pb-15.7Li is used as liquid breeder which is in direct contact with the structure material, e.g. EUROFER steel. Compatibility testing showed that high corrosion attack appears and that the dissolved steel components form precipitates with a high risk of system blockages. A reliable operation needs coatings as corrosion barriers. The earlier developed Hot-Dip Aluminisation (HDA) process has shown that Al-based scales can act as anti-corrosion as well as T-permeation barriers. Meanwhile two advanced electro-chemically based processes for deposition of Al-scales were successfully developed. The first (ECA = Electro-Chemical Al-deposition) is working with an organic electrolyte and the second one (ECX = Electro-Chemical-X-metal-deposition) is based on ionic liquids. Coatings in the μm-range were deposited homogeneously with exact controllable thicknesses. Metallurgical investigations showed the successful generation of protective scales and compatibility testing demonstrated the barrier function.

  3. Nano-engineering of superhydrophobic aluminum surfaces for anti-corrosion

    Science.gov (United States)

    Jeong, Chanyoung

    Metal corrosion is a serious problem, both economically and operationally, for engineering systems such as aircraft, automobiles, pipelines, and naval vessels. In such engineering systems, aluminum is one of the primary materials of construction due to its light weight compared to steel and good general corrosion resistance. However, because of aluminum's relatively lower resistance to corrosion in salt water environments, protective measures such as thick coatings, paints, or cathodic protection must be used for satisfactory service life. Unfortunately, such anti-corrosion methods can create other concerns, such as environmental contamination, protection durability, and negative impact on hydrodynamic efficiency. Recently, a novel approach to preventing metal corrosion has emerged, using superhydrophobic surfaces. Superhydrophobic surfaces create a composite interface to liquid by retaining air within the surface structures, thus minimizing the direct contact of the liquid environment to the metal surface. The result is a highly non-wetting and anti-adherent surface that can offer other benefits such as biofouling resistance and hydrodynamic low friction. Prior research with superhydrophobic surfaces for corrosion applications was based on irregular surface roughening and/or chemical coatings, which resulted in random surface features, mostly on the micrometer scale. Such microscale surface roughness with poor controllability of structural dimensions and shapes has been a critical limitation to deeper understanding of the anti-corrosive effectiveness and optimized application of this approach. The research reported here provides a novel approach to producing controlled superhydrophobic nanostructures on aluminum that allows a systematic investigation of the superhydrophobic surface parameters on the corrosion resistance and hence can provide a route to optimization of the surface. Electrochemical anodization is used to controllably modulate the oxide layer

  4. Formation of tunable graphene oxide coating with high adhesion.

    Science.gov (United States)

    Lin, Liangxu; Wu, Huaping; Green, Stephen J; Crompton, Joanna; Zhang, Shaowei; Horsell, David W

    2016-02-10

    Graphene oxide (GO) can be applied as a coating on metals, but few of these coatings have an adhesion suitable for practical applications. We demonstrate here how to form a GO coating on metals with a high adhesion (∼10.6 MPa) and tuneable surface, which can be further applied using similar/modified techniques for special applications (e.g. anti-corrosion and anti-biofouling). PMID:26814138

  5. Estimation of tribological anticorrosion properties of impregnated nitriding layers

    International Nuclear Information System (INIS)

    In this paper is described aim, experimental and test result of tribological anticorrosion properties of thin nitriding layer (12.5 μm) obtained on 45 steel grade in controlled gas-nitriding process (570oC, 4 h) impregnated with oil-based formulations, containing corrosion inhibitor BS-43, modified with tribological additives based on ashen organometallic compounds as well as ash-free organic compounds. It was stated, that tribological additives does not influence, in fact, on behaviour of corrosion resistance of nitriding layers impregnated with oil-base formulations mainly connected with inhibitor BS-43. Synergy of tribological additive and corrosion inhibitor is however more visible in modelling of wear resistance of nitriding layer. The influence nature of tribological additives in combination with corrosion inhibitor BS-43 is dependent on their kind and as result improves or worsens the wear resistance by friction. Hence in choice of impregnated formulation, which is enable to accomplish of tribological anticorrosion requirements, determined, above all, tribological additive. (author)

  6. Application Of Phenol/Amine Copolymerized Film Modified Magnesium Alloys: Anticorrosion And Surface Biofunctionalization.

    Science.gov (United States)

    Chen, Si; Zhang, Jiang; Chen, Yingqi; Zhao, Sheng; Chen, Meiyun; Li, Xin; Maitz, Manfred F; Wang, Jin; Huang, Nan

    2015-11-11

    Magnesium metal as degradable metallic material is one of the most researched areas, but its rapid degradation rate restricts its development. The current anticorrosion surface modification methods require expensive equipment and complicated operation processes and cannot continue to introduce biofunction on modified surface. In this study, the GAHD conversion coatings were fabricated on the surface of magnesium alloys (MZM) by incubating in the mixture solution of gallic acid (GA) and hexamethylenediamine (HD) to decrease the corrosion rate and provide primary amines (-NH2), carboxyl (-COOH), and quinone groups, which is supposed to introduce biomolecules on MZM. Chemical structures of the MZM-GAHD and MZM-HEP-GAHD were explored by analyzing the results of FTIR and XPS comprehensively. Furthermore, it was proved that the heparin (HEP) molecules were successfully immobilized on MZM-GAHD surface through carbodiimide method. The evaluation of platelet adhesion and clotting time test showed that MZM-HEP-GAHD had higher anticoagulation than MZM-GAHD. Through electrochemical detection (polarization curves and electrochemical impedance spectroscopy Nyquist spectrum) and immersion test (Mg(2+) concentration and weight loss), it was proved that compared to MZM, both the MZM-GAHD and MZM-HEP-GAHD significantly improved the corrosion resistance. Finally, in vivo experimentation indicated that mass loss had no significant difference between MZM-1:1, MZM-HEP-1:1, and MZM. However, the trend still suggested that MZM-1:1 and MZM-HEP-1:1 possessed corrosion resistance property. PMID:26479205

  7. Preparation of anti-corrosion films by microarc oxidation on an Al-Si alloy

    International Nuclear Information System (INIS)

    Thick ceramic films over 140 μm were prepared on Al-7% Si alloy by ac microarc oxidation in a silicate electrolyte. The film growth kinetics was determined by an eddy current technique and film growth features in different stages were discussed. The microstructure and composition profiles for different thick films were analyzed by scanning electron microscopy and energy dispersive X-ray spectroscopy. Their phase components were determined by X-ray diffraction. The electrochemical corrosion behaviors of bare and coated alloys were evaluated using potentiodynamic polarization curves, and their corrosion morphologies were observed. In the initial stage of oxidation, the growth rate is slow with 0.48 μm/min due to the effect of Si element though the current density is rather high up to 33 A/dm2. After the current density has decreased to a stable value of 11 A/dm2, the film mainly grows towards the interior of alloy. The film with a three-layer structure consists of mullite, γ-Al2O3, α-Al2O3 and amorphous phases. By microarc discharge treatment, the corrosion current of the Al-Si alloy in NaCl solution was significantly reduced. However, a thicker film has to be fabricated in order to obtain high corrosion-resistant film of the Al-Si alloy. Microarc oxidation is an effective method to form an anti-corrosion protective film on Si-containing aluminum alloys

  8. Choice of methods and determination of fracture toughness for anticorrosion cladding metal

    International Nuclear Information System (INIS)

    Technique for fracture toughness determination within wide temperature range is chosen. Experiment results on austenitic anticorrosion cladding metal cracking resistance are given in comparison with temperature dependence low envelope of 15Ch2MFA steel fracture toughness. From the data obtained it follows, that crack propagation direction along cladding metal does not affect KIJ fracture toughness value. It is shown, that fracture toughness values of anticorrosion layer material are higher, than those of low-alloy steel for cladding

  9. Fatigue crack propagation in the samples with anticorrosion bulding up

    International Nuclear Information System (INIS)

    Peculiarities of fatigue crack nucleation and propagation in the samples with anticorrosion building up from the concentrator placed in the melting zone are studied. A plate of experimental lot of 15Kh2NMFA steel δ=100 mm in thick has been used for sample production. The moment of nucleation is shown to depend on the level of loading and the coefficient of cycle asymmetry, if the stress concentrator is presented in the melting zone and there is a possibility for simultaneous ocurrence of the crack both in a base metal and in build-up metal. The character of crack development with different levels of loading and the coefficient of cycle asymmetry both in the base metal and in build-up one is similar. Approaching the sample surface the crack propagation rate is sharply increased

  10. 2-Mercaptobenzothiazole monolayers on zinc and silver surfaces for anticorrosion

    International Nuclear Information System (INIS)

    Anticorrosive behaviors of 2-mercaptobenzothiazole (MBT) self-assembled monolayers (SAMs) on silver and zinc electrodes were comparatively studied by means of electrochemical impedance spectroscopy (EIS). The promising inhibition effect of the MBT for silver and zinc from corrosion had been confirmed. The adsorption geometries of MBT monolayers on zinc and silver electrodes were observed by surface enhanced Raman scattering (SERS) technique. The SERS spectra implied that monolayers of MBT could be self-assembled on Ag surface through S10 and N3 atoms and the molecular plane should be tilted with respect to the surface. On Zn surface, MBT molecules formed monolayers via both S atoms and the other moieties of the molecule away from the surface. From the in situ electrochemical SERS results it can be found that MBT monolayers on both Ag and Zn surfaces experienced the changes of adsorption fashions as the potential shifting to more negative direction

  11. Composite coating prepared by micro-arc oxidation followed by sol-gel process and in vitro degradation properties

    International Nuclear Information System (INIS)

    A Mg phosphate coating was prepared on home-developed Mg-Zn-Ca alloy to improve its anticorrosion performance in simulated body fluid (SBF, Kokubo solution). The coating was prepared by micro-arc oxidation (MAO) method at the working voltage of 120-140 V. Evident improvement of anticorrosion was obtained even through the surface was porous. To further diminish the contact with SBF, a TiO2 layer was coated on the porous MAO layer by sol-gel dip coating followed by an annealing treatment. The coatings were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM) and energy dispersion spectroscopy (EDS). The electrochemical performance of the MAO and TiO2/MAO coated alloys was evaluated by anodic polarization measurements. The pores on Mg phosphate layer provided accommodation sites for the subsequent TiO2 sol-gel coating which sealed the pores and hence significantly enhanced the anticorrosion while single MAO coating only improve anticorrosion within a limited range. The present result indicates that fabrication of composite coatings is a significant strategy to improve the corrosion resistance of Mg-Zn-Ca alloy and other alloys, thus enhancing the potential of using Mg alloys as bio-implants.

  12. Estudio de las Propiedades Anticorrosivas del Benzoato de Hierro (III en Pinturas Base Solvente Study of Anticorrosive Properties of the Iron (III Benzoate in Solvent Based Paints

    Directory of Open Access Journals (Sweden)

    Guillermo Blustein

    2006-01-01

    Full Text Available La acción inhibidora del benzoato de hierro en electrodos de acero SAE 1010 en contacto con una suspensión acuosa fue estudiada mediante ensayos electroquímicos. Paralelamente, la eficiencia anticorrosiva de este producto incorporado a cubiertas orgánicas base solvente fue evaluada mediante ensayos de envejecimiento acelerado (cámara de niebla salina y de humedad. La evolución del comportamiento protector de la cubierta aplicada sobre paneles de acero pintados e inmersos en una solución 0.5M de NaClO4 fue periódicamente monitoreada por espectroscopía de impedancia electroquímica. Los resultados obtenidos indican que las pinturas formuladas con benzoato férrico presentan una capacidad anticorrosiva comparable a las formuladas con fosfato de cinc.This study investigated the inhibitory action of iron benzoate on SAE 1010 steel electrodes in aqueous suspensions using electrochemical assays. The anticorrosive efficiency of this product added to organic solvent-based coatings was also evaluated by means of accelerated weathering tests (salt spray cabinet and humidity chamber. The evolution of the protective behavior of the coating applied on steel panels and immersed in 0.5M NaClO4 solution was periodically checked by electrochemical impedance spectroscopy. The results obtained showed that paints formulated with ferric benzoate provide anticorrosive protection similar to those formulated with zinc phosphate.

  13. Corrosion Resistance of Zinc Coatings With Aluminium Additive

    Directory of Open Access Journals (Sweden)

    Votava Jiří

    2014-08-01

    Full Text Available This paper is focused on evaluation of anticorrosion protection of inorganic metal coatings such as hot-dipped zinc and zinc-galvanized coatings. The thickness and weight of coatings were tested. Further, the evaluation of ductile characteristics in compliance with the norm ČSN EN ISO 20482 was processed. Based on the scratch tests, there was evaluated undercorrosion in the area of artificially made cut. Corrosion resistance was evaluated in compliance with the norm ČSN EN ISO 9227 (salt-spray test. Based on the results of the anticorrosion test, there can be stated corrosion resistance of each individual protective coating. Tests were processed under laboratory conditions and may vary from tests processed under conditions of normal atmosphere.

  14. A new solvent-free super high build epoxy coating evaluated by marine corrosion simulation apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Yang, X. [Institute of Oceanology, Chinese Academic of Sciences, Qingdao 266071 (China); College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100 (China); Zhang, T. [College of Environmental and Safety Engineering, Qingdao University of Science and Technology, Qingdao 266042 (China); Wang, H. [College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100 (China); Hou, B. [Institute of Oceanology, Chinese Academic of Sciences, Qingdao 266071 (China)

    2012-04-15

    Coal tar epoxy and epoxy asphalt coating have been widely used to protect marine constructions conventionally. However, their use is being restricted for increasing environmental concerns. Therefore, solvent-free coating, i.e., coating without volatile organic compounds (VOCs) or hazardous air pollutant has become a new focus. Meanwhile, super high build (SHB) coating, having good anti-corrosion performance and environment-friendly feature, has become an important area of development in heavy-duty protection to marine constructions. Herein, we combine the virtues of solvent-free and SHB coating to introduce a new solvent-free SHB heavy-duty epoxy coating with no organic solvent and extremely low VOC content. Results show that the new coating is environment-friendly, and has excellent physical properties and anti-corrosion performance. The SHB coating performed much better than other three widely used coatings, especially in splash zone, the most dynamic area. The new solvent-free SHB coating provides an ideal substitute to coal tar epoxy and epoxy asphalt coating and is expected to be widely used for anti-corrosion of steel structures in splash, tidal, and immersed zones. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  15. Convenient routes to synthesize uncommon vaterite nanoparticles and the nanocomposites of alkyd resin/polyaniline/vaterite: The latter possessing superior anticorrosive performance on mild steel surfaces

    International Nuclear Information System (INIS)

    Polyaniline (PANI)/Precipitated Calcium Carbonate (PCC) composite materials are prepared, for the first time, starting from naturally occurring calcite, and are well characterized. X-ray diffraction (XRD) studies provide information for the presence of unstable vaterite form of PCC in the composites, with an average crystallite size of 26 nm, thus demonstrating the ability of PANI to stabilize, otherwise unstable, vaterite phase of CaCO3. Thermal analytical results (TGA and DSC) also provide information for the presence of only PANI and PCC, thus providing information for the purity of the composites. This method, therefore, provides a convenient route to prepare vaterite nanoparticles. Electron Microscopic (FE-SEM) images of the composites confirm that the voids of PANI chains are filled by the spherical nannoparticles of vaterite of diameter ∼ 24 nm, to result in spheres of the composites with an average diameter of 3–4 μm. FTIR spectra show that the PANI exists in its emaraldine form, weakly protonated when prepared at pH 5. Analysis of the FT-IR data for the four composites of PANI/vaterite gives the molar ratios of PANI:vaterite to be 1:4, 1:2, 1:1, 2:1, respectively. The PANI/PCC composites show electrical conductivity of ∼ 1.00 × 10−5 S cm−1, which is an impressive value to use these materials as anticorrosive coatings. AC impedance studies also give the conductivities of the PANI/PCC composites to be corresponding to a weakly electronically-conductive emeraldine form of PANI, with equal contributions from the ionic and electronic components, irrespective of the different amounts of vaterite or calcite present in the composites. The DC polarization test confirms equal transport numbers for ions and electrons in PANI samples. The above composites of PANI/vaterite, and a composite of 1:1 molar ratio of PANI/calcite, were mixed with alkyd resin and xylene, separately, to prepare anticorrosive coatings on mild steel (Mole percentages: 98.90% Fe, 0

  16. Preparation of anti-corrosion films by microarc oxidation on an Al-Si alloy

    Energy Technology Data Exchange (ETDEWEB)

    Xue Wenbin [Key Laboratory of Beam Technology and Materials Modification of Ministry of Education, Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing 100875 (China)]. E-mail: xuewb@bnu.edu.cn; Shi Xiuling [Key Laboratory of Beam Technology and Materials Modification of Ministry of Education, Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing 100875 (China); Hua Ming [Key Laboratory of Beam Technology and Materials Modification of Ministry of Education, Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing 100875 (China); Li Yongliang [Analytical and Testing Center, Beijing Normal University, Beijing 100875 (China)

    2007-05-15

    Thick ceramic films over 140 {mu}m were prepared on Al-7% Si alloy by ac microarc oxidation in a silicate electrolyte. The film growth kinetics was determined by an eddy current technique and film growth features in different stages were discussed. The microstructure and composition profiles for different thick films were analyzed by scanning electron microscopy and energy dispersive X-ray spectroscopy. Their phase components were determined by X-ray diffraction. The electrochemical corrosion behaviors of bare and coated alloys were evaluated using potentiodynamic polarization curves, and their corrosion morphologies were observed. In the initial stage of oxidation, the growth rate is slow with 0.48 {mu}m/min due to the effect of Si element though the current density is rather high up to 33 A/dm{sup 2}. After the current density has decreased to a stable value of 11 A/dm{sup 2}, the film mainly grows towards the interior of alloy. The film with a three-layer structure consists of mullite, {gamma}-Al{sub 2}O{sub 3}, {alpha}-Al{sub 2}O{sub 3} and amorphous phases. By microarc discharge treatment, the corrosion current of the Al-Si alloy in NaCl solution was significantly reduced. However, a thicker film has to be fabricated in order to obtain high corrosion-resistant film of the Al-Si alloy. Microarc oxidation is an effective method to form an anti-corrosion protective film on Si-containing aluminum alloys.

  17. Synthesis, characterization, and controlled release anticorrosion behavior of benzoate intercalated Zn-Al layered double hydroxides

    International Nuclear Information System (INIS)

    Graphical abstract: The benzoate anion released from Zn-Al LDHs provides a more effective long-term protection against corrosion of Q235 carbon steel in 3.5% NaCl solution. Highlights: → A benzoate anion corrosion inhibitor intercalated Zn-Al layered double hydroxides (LDHs) has been assembled by coprecipitation method. → The kinetic simulation indicates that the ion-exchange one is responsible for the release process and the diffusion through particle is the rate limiting step. → A significant reduction of the corrosion rate is observed when the LDH nanohybrid is present in the corrosive media. -- Abstract: Corrosion inhibitor-inorganic clay composite including benzoate anion intercalated Zn-Al layered double hydroxides (LDHs) are assembled by coprecipitation. Powder X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectrum analyses indicate that the benzoate anion is successfully intercalated into the LDH interlayer and the benzene planes are vertically bilayer-positioned as a quasi-guest ion-pair form in the gallery space. Kinetic simulation for the release data, XRD and FT-IR analyses of samples recovered from the release medium indicate that ion-exchange is responsible for the release process and diffusion through the particle is also indicated to be the rate-limiting step. The anticorrosion capabilities of LDHs loaded with corrosion inhibitor toward Q235 carbon steel are analyzed by polarization curve and electrochemical impedance spectroscopy methods. Significant reduction of corrosion rate is observed when the LDH nanohybrid is present in the corrosive medium. This hybrid material may potentially be applied as a nanocontainer in self-healing coatings.

  18. Corrosion Resistance of Electroless Ni-Cu-P Ternary Alloy Coatings in Acidic and Neutral Corrosive Mediums

    OpenAIRE

    Mbouillé Cissé; Mohamed Abouchane; Tayeb Anik; Karima Himm; Rida Allah Belakhmima; Mohamed Ebn Touhami; Rachid Touir; Abderrahmane Amiar

    2010-01-01

    Electroless Ni-Cu-P alloy coatings were deposited on the ordinary steel substrate in an acidic hypophosphite-type plating bath. These coatings were characterized by a scanning electron microscope (SEM) and an X-ray diffraction. The micrograph shows that coating presents a nodular aspect and is relatively homogeneous and very smooth. The EDX analysis shows that the coating contains 12 wt.% of phosphorus element with a predominance of nickel element. In addition, the anticorrosion properties of...

  19. Effects of Nano Pigments on the Corrosion Resistance of Alkyd Coating

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Alkyd coatings embedded with nano-TiO2 and nano-ZnO pigments were prepared. The effects of nano pigments on anticorrosion performance of alkyd coatings were investigated using electrochemical impedance spectrum (EIS). For the sake of comparison, the corrosion protection of alkyd coatings with conventional TiO2 and ZnO was also studied. It was found that nano-TiO2 pigment improved the corrosion resistance as well as the hardness of alkyd coatings. The optimal amount of nano-TiO2 in a colored coating for corrosion resistance was 1%. The viscosities of alkyd coatings with nanometer TiO2 and ZnO and conventional TiO2 and ZnO pigments were measured and the relation between viscosity and anticorrosion performance was discussed.

  20. Experimental Research on GIS Anticorrosion in Marine/Coastal Substation%海上/沿海变电站GIS设备防腐试验及研究

    Institute of Scientific and Technical Information of China (English)

    江玉蓉; 王霄峰; 符杨; 葛红花

    2012-01-01

    海上或沿海变电站气体绝缘开关设备(GIS)长期在高温高湿的海洋环境下,其外壳多采用铝合金及防腐涂层,它们的耐腐蚀性可满足陆上输变电的要求,这些材料及涂层是否满足海洋大气环境的耐腐蚀要求需要进行研究。利用盐雾试验箱对GIS铝合金封板进行耐盐雾腐蚀性能的检测,并最终做出评价。%Due to the long-term exposure to the oceanic atmosphere with high temperature and humidity,the Gas insulated switchgears(GIS) in marine or coastal substations require aluminum alloy and anticorrosion coating to be applied to their surface.Although their corrosion resistance is reliable to power transmission on the land,it needs further research to determine whether it can stand the oceanic environment.In this paper,the anticorrosion properties of GIS aluminum alloy sealing plate are measured by the salt spray test,and thereby their corrosion resistance to oceanic atmosphere is evaluated.

  1. Multilayer ceramic coating for impeding corrosion of sintered NdFeB magnets

    Institute of Scientific and Technical Information of China (English)

    A.Ali; A.Ahmad; K.M.Deen

    2009-01-01

    Sintered NdFeB magnets have complex microstructure that makes them susceptible to corrosion in active environments.The current paper evaluated the anticorrosion characteristics of multilayer titanium nitride ceramic coating applied through cathodic arc physical vapour deposition(CAPVD) for protection of sintered NdFeB permanent magnets.The performance of ceramic coating was compared to the electrodeposited nickel coating having a copper interlayer.Electrochemical impedance spectroscopy(EIS) and cyclic polar...

  2. The adsorption of an epoxy acrylate resin on aluminium alloy conversion coatings

    OpenAIRE

    Grilli, R; Abel, ML; Baker, MA; Dunn, B.; Watts, JF

    2011-01-01

    A thermodynamic study of the adsorption of an epoxy acrylate resin used for UV-cured coatings on two different anticorrosion pretreatments on aluminium alloys relevant to aerospace industry has been undertaken. Aluminium alloy Al2219 specimens, treated with an inorganic chromate based conversion coating (Alodine 1200S) and an organic titanium based conversion coating (Nabutan STI/310), were immersed in solutions of different concentrations of the resin and adsorption isotherms were determined...

  3. Evaluation of anti-corrosive protection stability in dual temperature separation installations

    International Nuclear Information System (INIS)

    Reduction of corrosive effects in the installations for heavy water production by the dual temperature procedure is obtained by deposing an adherent passivation layer of thermo-chemically stable against H2O-H2S medium iron sulfides on the inner surface of the equipment. The procedure is the result of 15 years of research, experimentation and testing in the frame of the pilot of heavy water production at INC-DTCI-ICIS Rm.Valcea. The following main objectives were realized in this field: - anti-corrosive protection against the hydrogen sulfide action; - conservation of anti-corrosive protections; - regeneration of anti-corrosive protection; - evaluation of the influence of working conditions upon the passivation layer stability. The results have been certified, patented and applied in the frame of the industrial units for heavy water production at ROMAG SA, Romania

  4. Present Status and Research Progress of Anti-corrosion Technology in Pipeline%管道内防腐技术现状与研究进展

    Institute of Scientific and Technical Information of China (English)

    赵帅; 兰伟

    2015-01-01

    介绍了石油管道内溶解氧、二氧化碳、硫化氢、以及二氧化碳和硫化氢协同腐蚀的机理. 综述了油气管道内防腐技术,现阶段主要的处理方式是选择耐蚀金属材料或非金属材料、添加缓蚀剂、涂层防腐和衬里防腐. 分析了各种内防腐技术的优缺点,认为管道内防腐在未来的发展方向是将基材选择、添加缓蚀剂、内涂镀层和内衬里技术进行综合,以减缓管道内的腐蚀. 低碳钢表面镀镍层自纳米合金化技术,即是集中内防腐技术的综合运用,得到了表面无缝冶金结合的高耐蚀性能管材,是未来发展趋势的代表.%The co-corrosion mechanism of oil and gases such as dissolved oxygen, carbon dioxide, hydrogen sulfide as well as carbon dioxide and hydrogen sulfide in the pipeline was described. The anti-corrosion technology of oil and gas in pipeline was re-viewed, including selection of corrosion resistant metallic materials or non-metallic materials, addition of corrosion inhibitor, coat-ing technology and lining technology. The paper analyzed advantages and disadvantages of various anti-corrosion technology and proposed that the future development trend of pipeline corrosion would be combination of substrate selection with addition of corro-sion inhibitors and internal lining technology for coating and lining to slow down the corrosion inside the pipe. Low carbon steel nickel-plated layer by nano alloying technology, which is the integrated utilization of concentrated anti-corrosion technology to ob-tain high metallurgical bonding surface seamless pipe with high corrosion resistance, is representative of future trends.

  5. Boron nitride nanosheets as oxygen-atom corrosion protective coatings

    International Nuclear Information System (INIS)

    The research of two-dimensional nanomaterials for anticorrosion applications is just recently burgeoning. Herein, we demonstrate the boron nitride nanosheets (BNNSs) coatings for protecting polymer from oxygen-atom corrosion. High-quality BNNSs, which are produced by an effective fluid dynamics method with multiple exfoliation mechanisms, can be assembled into coatings with controlled thickness by vacuum filtration. After exposed in atom oxygen, the naked polymer is severely corroded with remarkable mass loss, while the BNNSs-coated polymer remains intact. Barrier and bonding effects of the BNNSs are responsible for the coating's protective performance. These preliminary yet reproducible results pave a way for resisting oxygen-atom corrosion

  6. Cyclic corrosion crack resistance of anticorrosion cladding - vessel steel welded joint

    International Nuclear Information System (INIS)

    Cyclic corrosion crack resistance of welded joint (vessel steel 15Kh2MFA - anticorrosion cladding of steel Sv - 07Kh25N13 - anticorrosion cladding of steel Sv - 04Kh20N10G2B) in reactor water of boric regulation at 80 deg C is investigated. The diagram of welded joint fatigue fracture is plotted. It is ascertained that Sv - 04Kh20N10G2B austenitic cladding has the lowest cyclic crack resistance. It is pointed out that in the crack the vertex of which is located in steel 15Kh2MFA conditions for hydrogen formation, which is able to cause embrittlement, are created

  7. Hydrogen–argon plasma pre-treatment for improving the anti-corrosion properties of thin Al2O3 films deposited using atomic layer deposition on steel

    International Nuclear Information System (INIS)

    The effect of H2–Ar plasma pre-treatment prior to thermal atomic layer deposition (ALD) and plasma-enhanced atomic layer deposition (PEALD) of Al2O3 films on steel for corrosion protection was investigated. Time-of-flight secondary ion mass spectrometry and transmission electron microscopy were used to observe the changes in the interface. The electrochemical properties of the samples were studied with polarization measurements, and the coating porosities were calculated from the polarization results for easier comparison of the coatings. Prior to thermal ALD the plasma pre-treatment was observed to reduce the amount of impurities at the interface and coating porosity by 1–3 orders of magnitude. The anti-corrosion properties of the PEALD coatings could also be improved by the pre-treatment. However, exposure of the pre-treatment plasma activated steel surface to oxygen plasma species in PEALD led to facile oxide layer formation in the interface. The oxide layer formed this way was thicker than the native oxide layer and appeared to be detrimental to the protective properties of the coating. The best performance for PEALD Al2O3 coatings was achieved when, after the plasma pre-treatment, the surface was given time to regrow a thin protective interfacial oxide prior to exposure to the oxygen plasma. The different effects that thermal and plasma-enhanced ALD have on the substrate-coating interface were compared. The reactivity of the oxygen precursor was shown to have a significant influence on substrate surface in the early stages of film growth and thereafter also on the overall quality of the protective film. - Highlights: • Influence of H2–Ar plasma pre-treatment to ALD coatings on steel was studied. • The pre-treatment modified the coating–substrate interface composition and thickness. • The pre-treatment improved the barrier properties of the coatings

  8. COATING LAYER AND CORROSION PROTECTION CHARACTERISTICS IN SEA WATER WITH VARIOUS THERMAL SPRAY COATING MATERIALS FOR STS304

    OpenAIRE

    SEONG-JONG KIM; YONG-BIN WOO

    2010-01-01

    We investigated the optimal method of application and the anticorrosive abilities of Zn, Al, and Zn + 15%Al spray coatings in protecting stainless steel 304 (STS304) in sea water. If a defect such as porosity or an oxide layer, causes STS304 to be exposed to sea water, and the thermal spray coating material will act as the cathode and anode, respectively. The Tafel experiments revealed that Al-coated specimens among applied coating methods had the lowest corrosion current densities. As the co...

  9. Corrosion Inhibition on SAE 1010 Steel by Nanoscale Exopolysaccharides Coatings Determined by Electrochemical and Surface Characterization

    Science.gov (United States)

    Plating, painting and the application of enamel are the most common anti-corrosion treatments. They are effective by providing a barrier of corrosion resistant material between the damaging environment and the structural material. Coatings start failing rapidly if scratched or damaged because a co...

  10. A new smart additive of reinforced concrete based on modified hydrotalcites: Preparation, characterization and anticorrosion applications

    NARCIS (Netherlands)

    Yang, Z.; Fischer, H.; Polder, R.

    2012-01-01

    A carbonate form of Mg-Al-hydrotalcite and its p-aminobenzoate (pAB) modified derivative (i.e.,Mg(2)Al-pAB) were synthesized and characterized by means of XRD and FT-IR. The anticorrosion behavior was evaluated based on open circuit potential (OCP) of carbon steel in simulated concrete pore solution

  11. ANTI-CORROSION PROPERTIES OF CARBOXYLIC ACID IN WATER-GLYCOL SOLUTIONS

    Directory of Open Access Journals (Sweden)

    BASHKIRCEVA N.Y.

    2012-01-01

    Full Text Available Sodium salts of carboxylic acids were investigated to evaluate the corrosion properties of the water-glycol solutions. Corrosion tests were performed by methods of gravimetry and galvanostatic dissolution with metals used in cooling systems. The compositions of anticorrosion systems and their concentration that provide the most effective inhibition of metals were determined.

  12. Quality and cost control of anti-corrosion management in nuclear electrical power plant

    International Nuclear Information System (INIS)

    According to the characteristics of nuclear electrical realm , this article summarizes the factors affecting the quality and cost of the anti-corrosion management in nuclear electrical power plant, various methods are provided to control these factors from multiple angles. (authors)

  13. Effects of tungsten contents on the microstructure, mechanical and anticorrosion properties of Zr–W–Ti thin film metallic glasses

    International Nuclear Information System (INIS)

    While thin film metallic glass (TFMG) materials have been studied widely due to their easy fabrication process and unique properties, the W-based or W-containing TFMGs have yet to be explored extensively. In this work, four W-containing Zr–W–Ti TFMGs were fabricated by a magnetron co-sputtering system. The power of W target was adjusted to obtain TFMGs with different W concentrations. The amorphous phase of TFMG was determined by X-ray diffraction and high resolution transmission electron microscopy. In cross-sectional morphologies, a vein fracture pattern was observed using field-emission scanning electron microscopy. Although the hardness of W-containing Zr–W–Ti TFMG was not very high, the hardness of coating increased with increasing W content to reach 7.6 GPa. Good adhesion quality and adequate corrosion resistance were also obtained for each Zr–W–Ti TFMGs. - Highlights: • Four Zr–W–Ti thin film metallic glasses (TFMGs) were grown by a magnetron co-sputtering unit. • The W content of TFMGs ranges from 20.0 to 31.5 at.%. • The hardness of TFMGs increases with W content and reaches 7.6 GPa. • Good adhesion and anti-corrosion properties are found for Zr–W–Ti TFMGs

  14. Effects of tungsten contents on the microstructure, mechanical and anticorrosion properties of Zr–W–Ti thin film metallic glasses

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Jen-Chun [Department of Materials Engineering, Ming Chi University of Technology, New Taipei, Taiwan (China); Lee, Jyh-Wei, E-mail: jefflee@mail.mcut.edu.tw [Department of Materials Engineering, Ming Chi University of Technology, New Taipei, Taiwan (China); Center for Thin Films Technologies and Applications, Ming Chi University of Technology, New Taipei, Taiwan (China); Department of Electronic Engineering, Chang Gung University, Taoyuan, Taiwan (China); Lou, Bih-Show [Chemistry Division, Center for General Education, Chang Gung University, Taoyuan, Taiwan (China); Li, Chia-Lin [Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, Taipei, Taiwan (China); Chu, Jinn P. [Department of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan (China)

    2015-06-01

    While thin film metallic glass (TFMG) materials have been studied widely due to their easy fabrication process and unique properties, the W-based or W-containing TFMGs have yet to be explored extensively. In this work, four W-containing Zr–W–Ti TFMGs were fabricated by a magnetron co-sputtering system. The power of W target was adjusted to obtain TFMGs with different W concentrations. The amorphous phase of TFMG was determined by X-ray diffraction and high resolution transmission electron microscopy. In cross-sectional morphologies, a vein fracture pattern was observed using field-emission scanning electron microscopy. Although the hardness of W-containing Zr–W–Ti TFMG was not very high, the hardness of coating increased with increasing W content to reach 7.6 GPa. Good adhesion quality and adequate corrosion resistance were also obtained for each Zr–W–Ti TFMGs. - Highlights: • Four Zr–W–Ti thin film metallic glasses (TFMGs) were grown by a magnetron co-sputtering unit. • The W content of TFMGs ranges from 20.0 to 31.5 at.%. • The hardness of TFMGs increases with W content and reaches 7.6 GPa. • Good adhesion and anti-corrosion properties are found for Zr–W–Ti TFMGs.

  15. Oleic acid-grafted chitosan/graphene oxide composite coating for corrosion protection of carbon steel.

    Science.gov (United States)

    Fayyad, Eman M; Sadasivuni, Kishor Kumar; Ponnamma, Deepalekshmi; Al-Maadeed, Mariam Al Ali

    2016-10-20

    An anticorrosion coating film based on the formation of nanocomposite coating is reported in this study. The composite consisted of chitosan (green matrix), oleic acid, and graphene oxide (nano filler). The nanocomposite coating was arranged on the surface of carbon steel, and the corrosion resistance was monitored using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PP). Compared to the pure chitosan (CS) coating, the corrosion resistance of oleic acid-modified chitosan/graphene oxide film (CS/GO-OA) is increased by 100 folds. Since the well-dispersed smart grafted nanolayers delayed the penetration rate of corrosive species and thus maintained long term anticorrosive stability which is correlated with hydrophobicity and permeability. PMID:27474635

  16. Corrosion Behavior of Zirconium Treated Mild Steel with and Without Organic Coating: a Comparative Study

    Science.gov (United States)

    Ghanbari, Alireza; Attar, Mohammadreza Mohammadzade

    2014-10-01

    In this study, the anti-corrosion performance of phosphated and zirconium treated mild steel (ZTMS) with and without organic coating was evaluated using AC and DC electrochemical techniques. The topography and morphology of the zirconium treated samples were studied using atomic force microscopy (AFM) and field emission scanning electron microscope (FE-SEM) respectively. The results revealed that the anti-corrosion performance of the phosphate layer was superior to the zirconium conversion layer without an organic coating due to very low thickness and porous nature of the ZTMS. Additionally, the corrosion behavior of the organic coated substrates was substantially different. It was found that the corrosion protection performance of the phosphate steel and ZTMS with an organic coating is in the same order.

  17. Effect of current density on the structure, composition and corrosion resistance of plasma electrolytic oxidation coatings on Mg–Li alloy

    International Nuclear Information System (INIS)

    Highlights: ► The PEO coatings exhibit tunable characteristics by controlling the current density. ► The coating formed at 5 A/dm2 exhibits the highest corrosion resistance. ► Anti-corrosion properties of PEO coatings are related to coating surface composition. - Abstract: The effect of current density on the oxidation process, morphology, composition and anti-corrosion properties of coatings are elucidated. X-ray photoelectron spectroscopy and X-ray diffraction analysis of coatings show that coatings prepared at different current densities are composed of MgO and γ-Mg2SiO4 and α-Mg2SiO4 phase. The chemical composition of PEO coatings varies from surface to the interior of the oxide coating. The PEO coatings exhibit tunable thickness, composition ratio, and porosity by controlling the current density, which ultimately affects film morphology and anti-corrosion properties. The superior corrosion resistance of coating obtained at 5 A/dm2 is attributed to the compactness of the barrier layer and the highest MgO/Mg2SiO4 ratio.

  18. Effect of current density on the structure, composition and corrosion resistance of plasma electrolytic oxidation coatings on Mg-Li alloy

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhijun [Key Laboratory of Superlight Materials and Surface Technology, College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001 (China); Yuan, Yi, E-mail: yi.yuan@hrbeu.edu.cn [Key Laboratory of Superlight Materials and Surface Technology, College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001 (China); Jing, Xiaoyan [Key Laboratory of Superlight Materials and Surface Technology, College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001 (China)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer The PEO coatings exhibit tunable characteristics by controlling the current density. Black-Right-Pointing-Pointer The coating formed at 5 A/dm{sup 2} exhibits the highest corrosion resistance. Black-Right-Pointing-Pointer Anti-corrosion properties of PEO coatings are related to coating surface composition. - Abstract: The effect of current density on the oxidation process, morphology, composition and anti-corrosion properties of coatings are elucidated. X-ray photoelectron spectroscopy and X-ray diffraction analysis of coatings show that coatings prepared at different current densities are composed of MgO and {gamma}-Mg{sub 2}SiO{sub 4} and {alpha}-Mg{sub 2}SiO{sub 4} phase. The chemical composition of PEO coatings varies from surface to the interior of the oxide coating. The PEO coatings exhibit tunable thickness, composition ratio, and porosity by controlling the current density, which ultimately affects film morphology and anti-corrosion properties. The superior corrosion resistance of coating obtained at 5 A/dm{sup 2} is attributed to the compactness of the barrier layer and the highest MgO/Mg{sub 2}SiO{sub 4} ratio.

  19. Preparation and Characterization of Muscovite Mica/UV Coating Materials for Steel

    International Nuclear Information System (INIS)

    This paper describes the exfoliation and surface modification of muscovite mica for UV coating formulation. For the exfoliation of the mica, hydrothermal process was used in the presence of lithium nitrate (LiNO3). After the cation exchange with Li+ ions, the surface of the mica was modified with several amphiphilic substances to increase compatibility and storage stability in UV coating formulation. Such a hydrophobic surface modification affected colloidal stability as well as dispersibility of the exfoliated mica in UV coating solution. Anticorrosive property of mica/UV coated steel plates was tested by salt spray test (SST) and compared with sodium montmorillonite (Na+ - MMT)/UV coated steel plates

  20. Crash-Induced Vibration and Safety Assessment of Breakaway-Type Post Structures Made of High Anticorrosion Steels

    OpenAIRE

    Lee, Sang-Youl

    2016-01-01

    This study deals with car crash effects and passenger safety assessment of post structures with breakaway types using high performance steel materials. To disperse the impact force when a car crashes into a post, the post could be designed with a breakaway feature. In this study, we used a new high anticorrosion steel for the development of advanced breakaways. Based on the improved Cowper-Symonds model, specific physical properties to the high anticorrosion steel were determined. In particul...

  1. Development of water-soluble anti-corrosives

    International Nuclear Information System (INIS)

    In addition to the new, non-pollution, water-soluble rust-proof agents, RUSMIN MK-9 and MK-11 and COAT-S, announced previously, Mitsubishi's Nagasaki Technical Institute has recently developed six more such agents, RUSMIN MK-9B, -53, -27, -45 and COAT-S and -V. (1) MK COAT-A and -V form protective films on the metal surface make it rust-proof for a prolonged period of time and yet, after serving their purposes, can be removed by water-washing without the need of alkaline degreasing of the metal surface. (2) RUSMIN MK-9B and -53 are additives for water in closed or open circulating cooling-water system. RUSMIN MK-9 is an additive for cooling water for various kinds of machine bearings used in the thermal power plant, as well as for secondary cooling water for the heat exchanger in the atomic power plant. RUSMIN MK-53 is an additive for cooling water for the heat exchanger in the chemical plant or for cooling water for the building air-conditioning. (3) RUSMIN MK-27 is an additive for sea water filling the ship's ballast tank or for sea water used in hydraulic systems in the chemical plant and water-making plant. Effluent containing RUSMIN MK-27 is completely pollution-free and hence can be discharged into stream or harbor water. (4) RUSMIN MK-45 is an additive for cooling water for the diesel engine. Compared with the conventional water-soluble, emulsion-type, and oily rust-proof agents, all these new agents are not poisonous and contain very little pollutants which are restricted by the Water Pollution Control Law. Effluents containing these agents, therefore, require no treatment before discharge. (author)

  2. [The effect of pH on anti-corrosion nature of amalgams].

    Science.gov (United States)

    Chen, W; Wang, G; Li, W

    1997-09-01

    Corrosion behavior of alloys are affected not only by themselves but also by environment, such as a change of pH. In this study, the corrosion behavior of four dental amalgams (L, C, DA, GK) in Fusayama saliva with different pH 6.65 and 4.00 are evaluated by electrochemical techniques. It seems that changes in pH may exert different effects on the four amalgams. In the acid environment DA exhibits best anti-corrosion nature and followed by GK, C, and L, which conforms to clinical observations. This may be resulted either from amalgams themselves or from conditions of corrosion products of amalgams' surface. Thus, consideration must be given to the changing oral environment when screening anti-corrosion alloys. PMID:11189292

  3. A study on anticorrosion effect in high-performance concrete by the pozzolanic reaction of slag

    International Nuclear Information System (INIS)

    The study examines the pozzolanic reaction brought by the addition of slag to the cement paste using the synchrotron radiation accelerator (SRA), the mercury intrusion porosimetry (MIP), and scanning electron microstructural analysis. The anticorrosion effect in high-performance concrete with and without slag added is also assessed by its electrical resistivity and permeability. Results show that pozzolanic reaction due to the addition of slag can decrease the amount of calcium hydroxide, reduce the volume of capillary pores (Pc), and lower its permeability, thus making the concrete more compact and durable. As evidenced by the enhanced electrical resistivity and reduced permeability, the addition of slag to high-performance concrete can indeed strength the anticorrosion effect

  4. Substantial enhancement in the anticorrosivity of AA6061 by Doxycycline hydrochloride drug

    OpenAIRE

    Mudigere Krishnegowda Pavithra; Thimmappa Venkatarangaiah Venkatesha; Mudigere Krishnegowda Punith Kumar; Nanjanagudu Subba Rao Anantha

    2015-01-01

    The significant anticorrosive property of the antibiotic drug doxycycline hydrochloride (DCH) was investigated by electrochemical techniques such as potentiodynamic polarization, electrochemical impedance and chronoamperometric techniques. DCH inhibited the pitting corrosion of aluminium alloy 6061 (AA6061) in 3.5% NaCl media with 90% efficiency. The adsorption of DCH on AA6061 conform Langmuir isotherm by means of physisorption.  Quantum chemical calculations were evaluated to ascertain the ...

  5. Substantial enhancement in the anticorrosivity of aluminium alloy 6061 by doxycycline hydrochloride drug

    OpenAIRE

    Pavithra, Mudigere Krishnegowda; Venkatesha, Thimmappa Venkatarangaiah; Kumar, Mudigere Krishnegowda Punith; Anantha, Nanjanagudu Subba Rao

    2015-01-01

    The significant anticorrosive property of the antibiotic drug doxycycline hydrochloride (DCH) was investigated by electrochemical techniques such as potentiodynamic polarization, electrochemical impedance and chronoamperometric techniques. DCH inhibited the pitting corrosion of aluminium alloy 6061 (AA6061) in 3.5% NaCl media with 90% efficiency. The adsorption of DCH on AA6061 conform Langmuir isotherm by means of physisorption. Quantum chemical calculations were evaluated to ascertain the ...

  6. Brittle fracture resistance of anti-corrosive cladding on pressure vessel

    International Nuclear Information System (INIS)

    This paper reports the estimation of brittle fracture resistance of austenitic-ferritic anticorrosive cladding metal, produced by submerged arc welding with the use of strip electrodes. The dependence of impact toughness and temperature both in as produced condition and after the exposure to a neutron fluence together with the temperature dependence of cladding metal static crack resistance were determined. The transition from ductile to brittle condition for cladding metal was found to be typical for a ferritic-perlitic steel

  7. Investigations of Local Corrosion Behavior of Plasma-Sprayed FeCr Nanocomposite Coating by SECM

    Science.gov (United States)

    Shi, Xi; Shu, Mingyong; Zhong, Qingdong; Zhang, Junliang; Zhou, Qiongyu; Bui, Quoc Binh

    2016-02-01

    FeCr alloy coating can be sprayed on low-carbon steel to improve the corrosion resistance because of FeCr alloy's high anti-corrosion capacity. In this paper, Fe microparticles/Cr nanoparticles coating (NFC) and FeCr microparticles coating (MFC) were prepared by atmospheric plasma spraying and NFC was heat-treated under hydrogen atmosphere at 800 °C (HNFC). EDS mapping showed no penetration of Ni in MFC and NFC while penetration of Ni occurred in HNFC. X-ray diffraction results indicated the form of the NiCrFe (bcc) solid solution in HNFC. SECM testing in 3.5 (wt.%) NaCl revealed that the anti-corrosion capacity of NFC improved compared with MFC, while HNFC improved further.

  8. Hybrid organic-inorganic coatings including nanocontainers for corrosion protection of magnesium alloy ZK30

    Energy Technology Data Exchange (ETDEWEB)

    Kartsonakis, I. A., E-mail: ikartsonakis@ims.demokritos.gr [IAMPPNM, NCSR ' DEMOKRITOS' , Sol-Gel Laboratory (Greece); Koumoulos, E. P.; Charitidis, C. A., E-mail: charitidis@chemeng.ntua.gr [School of Chemical Engineering NTUA (Greece); Kordas, G. [IAMPPNM, NCSR ' DEMOKRITOS' , Sol-Gel Laboratory (Greece)

    2013-08-15

    This study is focused on the fabrication, characterization, and application of corrosion protective coatings to magnesium alloy ZK30. Hybrid organic-inorganic coatings were synthesized using organic-modified silicates together with resins based on bisphenol A diglycidyl ether. Cerium molybdate nanocontainers (ncs) with diameter 100 {+-} 20 nm were loaded with corrosion inhibitor 2-mercaptobenzothiazole and incorporated into the coatings in order to improve their anticorrosion properties. The coatings were investigated for their anticorrosion and nanomechanical properties. The morphology of the coatings was examined by scanning electron microscopy. The composition was estimated by energy-dispersive X-ray analysis. The mechanical integrity of the coatings was studied through nanoindentation and nanoscratch techniques. Scanning probe microscope imaging of the coatings revealed that the addition of ncs creates surface incongruity; however, the hardness to modulus ratio revealed significant strengthening of the coating with increase of ncs. Studies on their corrosion behavior in 0.5 M sodium chloride solutions at room temperature were made using electrochemical impedance spectroscopy. Artificial defects were formatted on the surface of the films in order for possible self-healing effects to be evaluated. The results showed that the coated magnesium alloys exhibited only capacitive response after exposure to corrosive environment for 16 months. This behavior denotes that the coatings have enhanced barrier properties and act as an insulator. Finally, the scratched coatings revealed a partial recovery due to the increase of charge-transfer resistance as the immersion time elapsed.

  9. Influences of Al particles on the microstructure and property of electrodeposited Ni-Al composite coatings

    Science.gov (United States)

    Cai, Fei; Jiang, Chuanhai

    2014-02-01

    Ni-Al composite coatings with different contents of Al microparticles were prepared from a conventional Watt bath. The influences of Al particle loadings in the bath on the surface morphology, composition, texture, grain size, microstrain, residual stress and anti-corrosion of the Ni-Al composite coating were investigated. The friction coefficients of the coatings at 200 °C were also evaluated by a pin-on-disctribometer. The results showed that the surface morphology of the coatings changed from pyramid + colonied structure to colonied structure with increasing Al particle loadings. The (2 0 0) preferred orientation for pure Ni coating evolved to random orientation with increasing Al particle loadings. The grain size obtained the minimum value of 72.28 nm at Al particle loading of 100 g/L and the microstrain of the coating increased with increasing the Al particle loadings. The incorporation of Al particles decreased the residual stress of the electro-deposited coating and all the coatings deposited at different Al particle loadings possessed low residual stress. As the Al particle loading increased, the anti-corrosion of the Ni-Al coatings increased owing to the combined effect of increasing Al content in the coatings and the texture evolution from (2 0 0) plane to (1 1 1) plane. The wear result suggested that the increasing Al particle content did not improve the wear performance of the Ni-Al composite coatings.

  10. Coatings against corrosion and microbial adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Telegdi, J.; Szabo, T.; Al-Taher, F.; Pfeifer, E.; Kuzmann, E.; Vertes, A. [Chemical Research Center, Hungarian Academy of Sciences, 1025 Budapest, Pusztaszeri ut 59/67 (Hungary)

    2010-12-15

    A systematic study on anti-corrosion and anti-fouling effect of hydrophobic Langmuir-Blodgett and self-assembled molecular layers deposited on metal surfaces, as well as anti-microbial adhesion properties of coatings with biocide is presented. Both types of efficiencies produced by LB films are enhanced by Fe{sup 3+} ions built in the molecular film. The quaternary ammonium type biocide embedded into the cross-linked gelatin decreased significantly the microbial adhesion, the biofilm formation. (Copyright copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. Corrosion resistance and mechanical properties of pulse electrodeposited Ni-TiO2 composite coating for sintered NdFeB magnet

    International Nuclear Information System (INIS)

    Ni-TiO2 composite coating which was prepared under pulse current conditions was successfully performed on sintered NdFeB magnet. As a comparison, pure nickel coating was also prepared. The phase structure, the surface morphology, the chemical composition, the anti-corrosion performance of the coatings for magnets, the microhardness and the wearing resistance performance of the coatings were studied using X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), electrochemical technique, Vickers hardness tester and ball-on-disc tribometer, respectively. The results revealed that Ni-TiO2 composite coating provided excellent anti-corrosion performance for the magnets, and showed higher microhardness and better anti-wear performance.

  12. Lifetime prediction and failure analysis of organic coatings by EIS

    Institute of Scientific and Technical Information of China (English)

    YAN Rui; WU Hang; MA Shi-ning; XU Bin-shi

    2004-01-01

    Organic coatings are widely used to control the corrosion of steel structure. The anticorrosive property of these coatings depends on their barrier properties, making a separation between the corrosive medium and the substrate. But unavoidable completely small pores, cracks and other defects in organic coatings may cause ions, water, gases, and other corrosive species penetrate and distribute in the coatings, causing accumulation and swelling of coatings, so leading to the degradation of coatings. In addition, water affects the permeation of oxygen and other corrosive medium, consequently the presence of such substances at coating-metal interface promotes corrosion of metal substrate. So the absorbability of the coatings to water may be one of the most important factors in undercoating corrosion. In recent years, electrochemical impedance spectroscopy (EIS) has been established and frequently used as a non-destructive testing method for assessing the performance of organic coatings, especially for the determination of the water content in organic coatings, since the capacitance of the coatings is sensitive to the penetration of water. So from EIS it can extract a wealth of information on the electrochemical corrosion of coated steels, especially, it can be utilized to assess organic coatings used under particular surroundings. The principle, methods and application of EIS on evaluating life-span and analyzing failure mechanism of organic coatings are also introduced briefly. Combining other analysis techniques such as XRD, SEM and FTIR with electrochemical technique, it will blaze a way in studying degradation mechanism of organic coatings and estimating their lifetime.

  13. POLYETHERSULFONE COATING FOR MITIGATING CORROSION OF STEEL IN GEOTHERMAL ENVIRONMENT.

    Energy Technology Data Exchange (ETDEWEB)

    SUGAMA, T.

    2005-06-01

    Emphasis was directed toward evaluating the usefulness of a polyethersulfone (PES)-dissolved N-methyl pyrrolidone (NMP) solvent precursor as a low-temperature film-forming anti-corrosion coating for carbon steel in simulated geothermal environments at brine temperatures up to 300 C. A {approx} 75 {micro}m thick PES coating performed well in protecting the steel against corrosion in brine at 200 C. However, at {>=} 250 C, the PES underwent severe hydrothermal oxidation that caused the cleavage of sulfone- and ether-linkages, and the opening of phenyl rings. These, in turn, led to sulfone {yields} benzosulfonic acid and ether {yields} benzophenol-type oxidation derivative transformations, and the formation of carbonyl-attached open rings, thereby resulting in the incorporation of the functional groups, hydroxyl and carbonyl, into the coating. The presence of these functional groups raised concerns about the diminutions in water-shedding and water-repellent properties that are important properties of the anti-corrosion coatings; such changes were reflected in an enhancement of the magnitude of susceptibility of the coatings surfaces to moisture. Consequently, the disintegration of the PES structure by hydrothermal oxidation was detrimental to the maximum efficacy of the coating in protecting the steel against corrosion, allowing the corrosive electrolytes to infiltrate easily through it.

  14. Study on the deterioration process of bipolar coating using electrochemical impedance spectroscopy

    Science.gov (United States)

    Su, Xiaomei; Zhou, Qiong; Zhang, Qingyi; Zhang, Yu; Zhang, Hong

    2011-05-01

    A bipolar coating, which is composed of inner layer epoxy with nano SiO 2 modified by cetyltrimethylammonium bromide (CTAB) (containing positive fixed charge) and outer layer epoxy with nano SiO 2 modified by sodium dodecylbenzenesulfonate (SDBS) (containing negative charge), was prepared in this paper. Its deterioration process after exposure to 5% KCl solution was also studied by EIS measurement and SEM observation. The results indicate that the impedance module of the bipolar coating is about 1E+9 ohm after a longer time immersion period. The bipolar coating has a better anti-corrosion capacity than that of epoxy coating. The cation-selective outer layer in bipolar coating inhibits the aggressive anion, such as Cl - ion, passing through the outer coating. Similarly, the anion-selective inner layer inhibits the metal cation passing through the inner coating. Thus the bipolar coating can protect the metal substrate from corrosion effectively. The p-n junction of bipolar coating, which has great charge storage ability, is the key factor in the anti-corrosion capacity of bipolar coating.

  15. Coating for the fixation of superficial contamination of materials

    International Nuclear Information System (INIS)

    Low cost, commercially available and easy to apply coatings are examined to prevent metal corrosion and to limit cement dust formation during power reactor dismantling. Epoxy compounds are selected because of anticorrosive properties, ease of application on any support, even without preparation and they are efficient for 1 to 5 years. Containment and radiation resistance up to 600 Mrads are studied on samples coated with one or two layers. For application the airless system is the more appropriate. An equipment is concerned and for highly radioactive environment automation and remote operation with a modified commercial robot is studied

  16. Study of a new possibility to predict the behavior of high - performance anticorrosive protections applied on steel after their exposure in natural aggressive environments, respectively in laboratory accelerated conditions

    Directory of Open Access Journals (Sweden)

    Irina POPA

    2014-12-01

    Full Text Available As a result of the global warming, notable changes in the climatic regime of Romania were observed in the last 40-50 years by increasing of the maximum temperatures and decreasing of the minimum temperatures characteristic for each season. This paper makes reference to an experimental research regarding the actual severity of the Romanian climate and its effects toward some performant anticorrosive coatings applied on steel. Such performant anticorrosive protection systems were exposed in situ – marine and alpine environment - and in parallel, aiming to simulate the severe climatic actions through laboratory accelerated environments - neutral salt fog, condensation and temperature variations. The graphical representation and the interpretation of the adhesion to the steel surface by means of the variation of the class into which the paint was framed after performing the cross-cut test during the exposure provided information concerning a new possibility to predict the evolution of the degradation of the paint, by means of this characteristic experimentally determined.

  17. Application of micro-arc oxidation to anti-corrosion of columns of hydraulic supports%微弧氧化在液压支架立柱防腐中的应用

    Institute of Scientific and Technical Information of China (English)

    甄敬然; 路银川

    2012-01-01

    Most failures of the hydraulic support are caused by corrosion of the column of the hydraulic support. Based on traditional anti-corrosion methods, the paper introduced a new-type surface treatment technique-micro-arc oxidation, and analysed the effects of electric parameters on micro-arc oxidation coating. Test results showed that the micro-arc oxidation was a new-type feasible prevention measure for anti-corrosion of the column of the hydraulic support.%立柱腐蚀是导致液压支架失效的主要原因,在传统防腐方法的基础上,笔者研究了一种新型表面处理工艺——微弧氧化,分析求得对微弧氧化膜层性能影响的最优电参数。实践证明,在液压支架立柱防腐中微弧氧化是一种切实可行的防范措施。

  18. Boronized steels with corundum-baddeleyite coatings

    Directory of Open Access Journals (Sweden)

    P. Pokorny

    2016-07-01

    Full Text Available The paper describes preparation and properties of anti-corrosion and anti-abrasive coatings from corundum-baddeleyite ceramics deposited on surface of low-carbon boronized steel S235JRH-1.0038 (EN 10025-1 by plasma spraying method. Adhesive interlayers Fe2B reaches bond strength of up to 20 MPa in the pull-off tests, the ZrO2 - Al2O3 - SiO2 coatings have a value of fracture adhesion of 4 - 6 MPa. Hardness of these ceramic coatings on steel is as high as 1 800 HV100 and its polarization resistance is 1 600 Ω/cm2 to 4 000 Ω/cm2.

  19. Fabrication of superhydrophobic textured steel surface for anti-corrosion and tribological properties

    Science.gov (United States)

    Zhang, Hongmei; Yang, Jin; Chen, Beibei; Liu, Can; Zhang, Mingsuo; Li, Changsheng

    2015-12-01

    We describe a simple and rapid method to fabricate superhydrophobic textured steel surface with excellent anti-corrosion and tribological properties on S45C steel substrate. The steel substrate was firstly ground using SiC sandpapers, and then polished using diamond paste to remove scratches. The polished steel was subsequently etched in a mixture of HF and H2O2 solution for 30 s at room temperature to obtain the textured steel surface with island-like protrusions, micro-pits, and nano-flakes. Meanwhile, to investigate the formation mechanism of the multiscale structures, the polished steel was immersed in a 3 wt% Nital solution for 5 s to observe the metallographic structures. The multiscale structures, along with low-surface-energy molecules, led to the steel surface that displayed superhydrophobicity with the contact angle of 158 ± 2° and the sliding angle of 3 ± 1°. The chemical stability and potentiodynamic polarization test indicated that the as-prepared superhydrophobic surface had excellent corrosion resistance that can provide effective protection for the steel substrate. The tribological test showed that the friction coefficient of the superhydrophobic surface maintained 0.11 within 6000 s and its superhydrophobicity had no obvious decrease after the abrasion test. The theoretical mechanism for the excellent anti-corrosion and tribological properties on the superhydrophobic surface were also analyzed respectively. The advantages of facile production, anti-corrosion, and tribological properties for the superhydrophobic steel surface make it to be a good candidate in practical applications.

  20. Fabrication of super slippery sheet-layered and porous anodic aluminium oxide surfaces and its anticorrosion property

    Science.gov (United States)

    Song, Tingting; Liu, Qi; Liu, Jingyuan; Yang, Wanlu; Chen, Rongrong; Jing, Xiaoyan; Takahashi, Kazunobu; Wang, Jun

    2015-11-01

    Inspired by natural plants such as Nepenthes pitcher plants, super slippery surfaces have been developed to improve the attributes of repellent surfaces. In this report, super slippery porous anodic aluminium oxide (AAO) surfaces have fabricated by a simple and reproducible method. Firstly, the aluminium substrates were treated by an anodic process producing micro-nano structured sheet-layered pores, and then immersed in Methyl Silicone Oil, Fluororalkylsilane (FAS) and DuPont Krytox, respectively, generating super slippery surfaces. Such a good material with excellent anti-corrosion property through a simple and repeatable method may be potential candidates for metallic application in anti-corrosion and extreme environment.

  1. Detecting Weld Zone Over Anticorrosion Painting by Rotating Uniform Eddy Current Probe

    International Nuclear Information System (INIS)

    The authors have studied application of rotating uniform eddy current probe to detecting weld zone in steed material over anticorrosion painting. The probe detects not only weld position by the signal level but also weld direction by the signal phase. The experimental results have indicated that the probe provides a signal almost linear to its position with respect to weld zone center over the full width of weld. The signal of the probe is much less influenced by the painting thickness variation than that of the conventional differential pancake-coils probe

  2. ENERGY PECULIAR FEATURES PERTAINING TO NANO- TECHNOLOGY OF COATING DEPOSITION USING MIXED MATRICES FOR AUTOMOTIVE COMPONENTS

    Directory of Open Access Journals (Sweden)

    V. Ivashko

    2012-01-01

    Full Text Available A systematic analysis of factors that influence on the processes of  protective coating formation based on mixed matrices has been presented in the paper. The paper demonstrates a significant role of energy parameters of modifier drop-phase dispersed particles formed in the process of pneumatic spraying  and surface layer of a metal substrate on the mechanisms pertaining to formation of coating structure with optimal characteristics. Compositions of anticorrosive and tribological coatings for application in the designs of higher resource automotive components  have been proposed in the paper.

  3. The correlation between materials, processes and final properties in the pipeline coating system with polyethylene in triple layer; A correlacao entre materiais, processos e propriedades finais no sistema de revestimento de tubos com polietileno em tripla camada

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Luiz C.; Campos, Paulo H. [Confab Industrial S.A., Pindamonhangaba, SP (Brazil); Silva, Christian E.; Santos, Paulo T. [Soco-Ril do Brasil S.A., Pindamonhangaba, SP (Brazil)

    2003-07-01

    The use of anticorrosion coating is a common practice in industrial pipeline applications. Among the several coatings types to buried and submerged pipelines, over all, the Fusion Bonded Epoxy and Three Layer Polyethylene coating systems have been large employed. They have showed an excellent performance protecting the pipe metal from external corrosive environment, considerably decreasing the designed cathodic protection requirements, basically in the first years of pipeline operation. Coating system success depends on not only of a suitable design or of the materials technology, but also depends on the process parameters and the raw material characteristics exhibited during the application. In this paper will be presented in a theoretical approach how the process parameters and the raw materials characteristics may affect the three layer polyethylene anticorrosion coating final properties. (author)

  4. Structural characterization and corrosive property of Ni-P/CeO2composite coating

    Institute of Scientific and Technical Information of China (English)

    JIN Huiming; JIANG Shihang; ZHANG Linnan

    2009-01-01

    Electroless Ni-P/nano-CeO2 composite coating was prepared in acidic condition, and its microstructure and corrosive property were compared with its CeO2-free counterpart. Scanning electronic microscopy (SEM), transmission electronic microscopy (TEM), X-ray diffraction spectrometer (XRD), and differential scanning calorimeter (DSC) were used to examine surface morphology and microstructure of the coating. Corrosive investigation was carried out in 3%NaCl+5%H2SO4 solution. The results showed that Ni-P coating had partial amorphous structure mixed with nanocrystals, whereas the Ni-P/CeO2 coating had perfect amorphous structure. In high temperature condition, Ni3P precipitation and Ni crystallization occurred in both coatings but at different temperatures, whereas the Ni-P/CeO2 coating had sintered phase of NiCe2O4 spinels. The anticorrosion property and passivity were improved in the CeO2-containing coating due to its less liability to undergo local-cell corrosion than its CeO2-free counterpart. During the co-deposition process, some Cen+ (n=3, 4) ions may be adsorbed to the metal/solution interface, hinder nickel's crystal-typed deposition and promote phosphorous deposition. The nano-CeO2 doping finally resulted in the coating' perfect amorphous structure and good anti-corrosive property.

  5. Anti-corrosion performance of oxidized and oxygen plasma-implanted NiTi alloys

    International Nuclear Information System (INIS)

    Nickel-titanium shape memory alloys are useful orthopedic biomaterials on account of its super-elastic and shape memory properties. However, the problem associated with out-diffusion of harmful nickel ions in prolonged use inside the human body raises a critical safety concern. Titanium oxide films are deemed to be chemically inert and biocompatible and hence suitable to be the barrier layers to impede the leaching of Ni from the NiTi substrate to biological tissues and fluids. In the work reported in this paper, we compare the anti-corrosion efficacy of oxide films produced by atmospheric-pressure oxidation and oxygen plasma ion implantation. Our results show that the oxidized samples do not possess improved corrosion resistance and may even fare worse than the untreated samples. On the other hand, the plasma-implanted surfaces exhibit much improved corrosion resistance. Our work also shows that post-implantation annealing can further promote the anti-corrosion capability of the samples

  6. Lanthanum-exchanged zeolite and clay as anticorrosive pigments for galvanized steel

    Institute of Scientific and Technical Information of China (English)

    S. Roselli; N. Bellotti; C. Deyá; M. Revuelta; B. del Amo; R. Romagnoli

    2014-01-01

    A wide variety of inhibitive pigments is now being offered as possible alternatives to chromate and lead compounds for painted metals protection. Unfortunately, the most wide spread of these substitute pigments, zinc phosphate, has, at present, raised some environmental concern because phosphate causes the eutrophication of water courses and zinc itself is toxic. The aim of this re-search was to study the anticorrosive performance of a mixture consisting of zinc phosphate, modified zeolite and clay (bentonite) in order to diminish phosphate content in paints. The zeolite and the clay were exchanged with La(III) ions, as inorganic green inhibitor. In the first step, the anticorrosion protection by La(III) ions in solution was assessed by electrochemical tests. In the second step, an epoxy-polyamide paint formulated with the pigment mixture applied on galvanized panels was studied by salt spray test and electro-chemical noise measurements (ENM). The results showed that it was possible to replace part of the zinc phosphate content in the paint with the exchanged zeolite and the clay.

  7. [Research on anti-corrosion of Thiobacillus for the geopolymer solidification MSWI fly ash].

    Science.gov (United States)

    Jin, Man-Tong; Sun, Xin; Dong, Hai-Li; Jin, Zan-Fang

    2012-09-01

    In order to discuss the anti-Thiobacillus corrosion performance of geopolymer solidification MSWI fly ash, the research simulated the Thiobacillus corrosion process by experiment, investigated the change of mass, compressive strength, leaching concentration. The results showed that geopolymer had a good anti-corrosion ability: weight loss within 1%, the compressive strength still reached 21.88 MPa after 28 days, the corrosion resistance coefficient was above 0.9. The maximum leaching concentration of Cr, Cu, Zn, Cd, Hg, Pb were 107.7 microg x L(-1), 22.71 microg x L(-1), 39.18 microg x L(-1), 0.56 microg x L(-1), 34.84 microg x L(-1) and 3.03 microg x L(-1), respectively. And the leaching concentration of geopolymer reduced with the immersion time, showed a good anti-Thiobacillus corrosion performance. Through the X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscope spectra of geopolymer, we investigated the microstructure and mechanism of geopolymer anti-corrosion. PMID:23243892

  8. Anticorrosion imidazolium ionic liquids as the additive in poly(ethylene glycol) for steel/Cu-Sn alloy contacts.

    Science.gov (United States)

    Cai, Meirong; Liang, Yongmin; Zhou, Feng; Liu, Weimin

    2012-01-01

    3-((1H-benzo[d][1,2,3]triazol-1-yl)methyl)-1-methyl-1H-imidazolium hexafluorophosphates ([BTAMIM][PF6]) ionic liquids (ILs) were evaluated as friction reduction, antiwear (AW) and anticorrosion additives in poly(ethylene glycol) (PEG) for steel/Cu-Sn alloy contacts at 100 degrees C. The physical properties of PEG with the additive were measured. The anticorrosion properties of [BTAMIM][PF6] was assessed via the accelerated corrosion test, which reveals the excellent anticorrosion properties in comparison with selected conventional ILs that have no benzotriazole group. Tribological results indicated that [BTAMIM][PF6] as additives could effectively reduce the friction and wear of sliding pairs in PEG. The tribological properties were generally better than the normally used dibutyl phosphite (T304) and conventional ILs L-P108 in PEG. The wear mechanisms are tentatively discussed according to the morphology observation of worn surfaces of Cu-Sn alloy discs by scanning electron microscopy (SEM) and surface composition analysis by X-ray photoelectron spectroscopy (XPS), which revealed complex tribochemical reactions during the sliding process leading to a surface protective film composed of [Cu(-C6H5N3-R)], Cu20, CuF2 and C-O bond containing compound is formed. A strong interaction between benzotriazole and the surface of the Cu alloy was proposed to account for the excellent friction reduction, anti-wear and anti-corrosion capability improvement. PMID:23285627

  9. Antimicrobial action and anti-corrosion effect against sulfate reducing bacteria by lemongrass (Cymbopogon citratus) essential oil and its major component, the citral.

    Science.gov (United States)

    Korenblum, Elisa; Regina de Vasconcelos Goulart, Fátima; de Almeida Rodrigues, Igor; Abreu, Fernanda; Lins, Ulysses; Alves, Péricles Barreto; Blank, Arie Fitzgerald; Valoni, Erika; Sebastián, Gina V; Alviano, Daniela Sales; Alviano, Celuta Sales; Seldin, Lucy

    2013-01-01

    The anti-corrosion effect and the antimicrobial activity of lemongrass essential oil (LEO) against the planktonic and sessile growth of a sulfate reducing bacterium (SRB) were evaluated. Minimum inhibitory concentration (MIC) of LEO and its major component, the citral, was 0.17 mg ml-1. In addition, both LEO and citral showed an immediate killing effect against SRB in liquid medium, suggesting that citral is responsible for the antimicrobial activity of LEO against SRB. Transmission electron microscopy revealed that the MIC of LEO caused discernible cell membrane alterations and formed electron-dense inclusions. Neither biofilm formation nor corrosion was observed on carbon steel coupons after LEO treatment. LEO was effective for the control of the planktonic and sessile SRB growth and for the protection of carbon steel coupons against biocorrosion. The application of LEO as a potential biocide for SRB growth control in petroleum reservoirs and, consequently, for souring prevention, and/or as a coating protection against biocorrosion is of great interest for the petroleum industries. PMID:23938023

  10. Corrosion resistance, composition and structure of RE chemical conversion coating on magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Golden yellow rare earths chemical conversion coating was obtained on the surface of magnesium alloy by immersing in cerium sulfate solution.The corrosion resistance of RE conversion coating was evaluated using immersion test and potentiodynamic polarization measurements in 3.5%NaCl solution.The morphologies of samples before corrosion and after corrosion were observed by SEM.The structures and compositions of the RE conversion coating were studied by means of XPS.XRD and IR.The results show that,the conversion coating consists of mainly two kinds of element Ce and O,the valences of cerium are+3 and+4.and OH exists in the coating.The anti-corrosion property of magnesium alloy is increased obviously by rare earths conversion coating,Its self-corrosion current density decreases and the coating has self-repairing capability in the corrosion process in 3.5%NaCl solution.

  11. Cerium oxide as conversion coating for the corrosion protection of aluminum

    Directory of Open Access Journals (Sweden)

    JELENA GULICOVSKI

    2013-11-01

    Full Text Available CeO2 coatings were formed on the aluminum after Al surface preparation, by dripping the ceria sol, previously prepared by forced hydrolysis of Ce(NO34. The anticorrosive properties of ceria coatings were investigated by the electrochemical impedance spectroscopy (EIS during the exposure to 0.03 % NaCl. The morphology of the coatings was examined by the scanning electron microscopy (SEM. EIS data indicated considerably larger corrosion resistance of CeO2-coated aluminum than for bare Al. The corrosion processes on Al below CeO2 coating are subjected to more pronounced diffusion limitations in comparison to the processes below passive aluminum oxide film, as the consequence of the formation of highly compact protective coating. The results show that the deposition of ceria coatings is an effective way to improve corrosion resistance for aluminum.

  12. Development of a new solvent-free flow efficiency coating for natural gas pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Fogg, Graham A.; Morse, Jennifer [Bredero Shaw, Houston, TX (United States)

    2005-07-01

    Pipeline design engineers have traditionally considered external anti-corrosion coatings for the protection of gas transmission pipelines, with less consideration given to the benefits of internal flow efficiency coatings. This paper reviews the benefits of using a traditional solvent-based flow efficiency coating, and the relationship between the internal surface roughness of a pipe, the pressure drop across the pipeline, and the maximum flow rate of gas through the pipeline. To improve upon existing solvent-based flow efficiency coatings, a research program was undertaken to develop a solvent-free coating. The stages in the development of this coating are discussed, resulting in the plant application of the coating and final qualification to API RP 5L2. (author)

  13. Enhancement of the corrosion protection of electroless Ni–P coating by deposition of sonosynthesized ZnO nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Sharifalhoseini, Zahra [Sonochemical Research Center, Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91779 Mashhad (Iran, Islamic Republic of); Entezari, Mohammad H., E-mail: entezari@um.ac.ir [Sonochemical Research Center, Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91779 Mashhad (Iran, Islamic Republic of); Environmental Chemistry Research Center, Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91779 Mashhad (Iran, Islamic Republic of)

    2015-10-01

    Graphical abstract: Enhancement of the corrosion protection of electroless Ni–P layer by ZnO nanoparticles deposition and the comparison with the classical and sonochemical Ni–P coatings. - Highlights: • Unique effects of ultrasound were investigated on the anticorrosive performance of electroless Ni–P coating. • Sonoynthesis of ZnO NPs and its deposition were performed on the surface of Ni–P coating. • ZnO as an anticorrosive has a critical role in the multifunctional surfaces. • Electrochemical properties of all fabricated samples were compared with each other. - Abstract: Ni–P coatings were deposited through electroless nickel plating in the presence and absence of ultrasound. The simultaneous synthesis of ZnO nanoparticle and its deposition under ultrasound were also carried out on the surface of Ni–P layer prepared by the classical method. The morphology of the surfaces and the chemical composition were determined by scanning electron microscopy(SEM) and energy dispersive spectroscopy (EDS), respectively. Electrochemical techniques were applied for the corrosion behavior studies. The Ni–P layer deposited by ultrasound showed a higher anticorrosive property than the layer deposited by the classical method. The ZnO nanoparticles deposited on the surface of Ni–P layer significantly improved the corrosion resistance.

  14. Raman spectroscopy of fluoropolymer conformal coatings on electronic boards

    Science.gov (United States)

    Rodošek, Mirjana; Perše, Lidija Slemenik; Mihelčič, Mohor; Koželj, Matjaž; Orel, Boris; Bengű, Başak; Sunetci, Onder; Pori, Pauli; Vuk, Angela Šurca

    2014-09-01

    Fluoropolymer conformal coatings were applied to electronic boards (EBs) and cured at room temperature or 80°C. The coatings were first deposited on model substrate, i.e. aluminium alloy AA 2024 and tested for their anticorrosion properties with a potentiodynamic polarisation technique. The cathodic current densities ranged from 10-9-10-10 A/cm2, approaching the lower current limit after the addition of TiO2 nanoparticles into the formulation. Application of fluoropolymer-based formulation was performed via spray-coating deposition. Examination of the coverage of EBs under UV light, which is commonly used in industry, revealed that some components might not be entirely covered. In the search for other possible analytical tools of coverage with protective coatings, optical microscopy and confocal Raman spectroscopy were investigated.

  15. 2-Mercaptobenzothiazole doped chitosan/11-alkanethiolate acid composite coating: Dual function for copper protection

    Science.gov (United States)

    Bao, Qi; Zhang, Dun; Wan, Yi

    2011-10-01

    Chitosan (CS) hydrogel loaded with the well-known corrosion inhibitor 2-mercaptobenzothiazole (MBT) has been introduced into a composite coating to improve copper protection. This composite coating, which has both anticorrosion and antibacterial properties, was fabricated onto the surface of copper by combining a simple self-assembled monolayer technique with a sol-gel method. The anti-corrosion ability of the coating in 3.5 wt.% NaCl solution was investigated by electrochemical methods including potentiodynamic polarization and electrochemical impedance spectroscopy. The protection efficiency of the coating is 97.70%, calculated on the basis of the corrosion current density. The stability and integrity of the composite coating were evaluated by field emission scanning electron microscopy (FESEM) and energy dispersive spectrometry (EDS). The FESEM and EDS results suggest that the composite coating endows the copper substrate with antibacterial properties, as untreated bare copper underwent microbiologically influenced corrosion in the presence of sulphate reducing bacteria (SRB). This antibacterial feature was further confirmed by the SRB culture method. In a 3.5% NaCl solution and highly corrosive SRB culture media, the as-prepared CS based composite coating gave corrosion protection by exhibiting better barrier effects against the attack of aggressive environments.

  16. Energy conservation research of dehumidification system for main cable anticorrosion of suspension bridge

    Institute of Scientific and Technical Information of China (English)

    Chen Ce; Fan Liangkai; Feng Zhaoxiang; Pen Guanzhong

    2011-01-01

    The necessity of the main cable anticorrosion for suspension bridge is described, and operating principles and composition of main cable dehumidification system are analyzed. An idea using the waste heat of high temperature outlet air of dehumidification system to heat up regeneration air of rotary-type dehumidifier is put forward in this paper. The concrete scheme is to install a heat exchanger on air-out pipeline of roots blower and air-in pipeline of regeneration electric heater of rotary dehumidifier. Air preheated by the heat exchanger enters regeneration electric heater of rotary-type dehumidifier. Energy conservation of main cable dehumidification system for the Yangtze River highway bridge is calculated, and the results show that energy conservation rate can reach 44 %.

  17. ANTICORROSION POTENTIAL OF HYDRALAZINE FOR CORROSION OF MILD STEEL IN 1M HYDROCHLORIC ACID SOLUTION

    Directory of Open Access Journals (Sweden)

    B. M. Prasanna

    2015-05-01

    Full Text Available Anticorrosion potential of mild steel by Hydralazine as corrosion inhibitor for mild steel in 1M hydrochloric acid was investigated by chemical and electrochemical measurements at 303-333 K temperature. The maximum inhibition efficiency of inhibitor by Weight loss method is around 90%, Tafel polarization method is around 85%; electrochemical impedance spectroscopy measurement around 90% at 1250 ppm of Hydralazine in. The result shows that the inhibition efficiency increases with I 1M hydrochloric acid. Hydralazine acts as a mixed type inhibitor which inhibits the corrosion of mild steel due to the adsorption on metal surface. This adsorption system obeys the Langmuir adsorption isotherm.Activation parameters explains the effect of temperature with inhibition efficiency of inhibitor molecule.SEM images of inhibited mild steel strips shows a formation of passive protective film over the surface.

  18. Metallurgical causes of hot cracking during repair of anticorrosion liner of pressure vessel

    International Nuclear Information System (INIS)

    The problem of hot cracking in the 25Cr13Ni liner zone was addressed during the development of the technology of welded repair joints of reactor pressure vessels with anticorrosion cladding. The occurrence of low-melting-point eutectics on the boundaries of grains based on NbX, NbNi3 and Nb3Si phases was the metallurgical cause of the formation of crystallization cracks. During crystallization, such phases remain in the form of a liquation film on the boundaries of grains of the primary crystals. The weld metal shrinking is accompanied by the development of microcracks, which during the cooling can expand as far as the weld surface. (Z.S.). 6 tabs., 8 figs., 8 refs

  19. Polyaniline: a conductive polymer coating for durable nanospray emitters

    Science.gov (United States)

    Maziarz; Lorenz; White; Wood

    2000-07-01

    Despite the tremendous sensitivity and lower sample requirements for nanospray vs. conventional electrospray, metallized nanospray emitters have suffered from one of two problems: low mechanical stability (leading to emitter failure) or lengthy, tedious production methods. Here, we describe a simple alternative to metallized tips using polyaniline (PANI), a synthetic polymer well known for its high conductivity, anticorrosion properties, antistatic properties, and mechanical stability. A simple method for coating borosilicate emitters (1.2 mm o.d.) pulled to fine tapers (4 +/- 1 microm) with water-soluble and xylene-soluble dispersions of conductive polyaniline (which allows for electrical contact at the emitter outlet) is described. The polyaniline-coated emitters show high durability and are resistant to electrical discharge, likely because of the thick (yet optically transparent) coatings; a single emitter can be used over a period of days for multiple samples with no visible indication of the destruction of the polyaniline coating. The optical transparency of the coating also allows the user to visualize the sample plug loaded into the emitter. Examples of nanospray using coatings of the water-soluble and xylene-soluble polyaniline dispersions are given. A comparison of PANI-coated and gold-coated nanospray emitters to conventional electrospray ionization (ESI) show that PANI-coated emitters provide similar enhanced sensitivity that gold-coated emitters exhibit vs. conventional ESI. PMID:10883822

  20. Electrodeposition and Corrosion Resistance Properties of Zn-Ni/TiO2 Nano composite Coatings

    Directory of Open Access Journals (Sweden)

    B. M. Praveen

    2011-01-01

    Full Text Available Nano sized TiO2 particles were prepared by sol-gel method. TiO2 nano particles were dispersed in zinc-nickel sulphate electrolyte and thin film of Zn-Ni-TiO2 composite was generated by electrodeposition on mild steel plates. The effect of TiO2 on the corrosion behavior and hardness of the composite coatings was investigated. The film was tested for its corrosion resistance property using electrochemical, weight loss, and salt spray methods. The paper revealed higher resistance of composite coating to corrosion. Microhardness of the composite coating was determined. Scanning electron microscope images and X-ray diffraction patterns of coating revealed its fine-grain nature. Average crystalline size of the composite coating was calculated. The anticorrosion mechanism of the composite coating was also discussed.

  1. Cyclotriphosphazene and TiO2 reinforced nanocomposite coated on mild steel plates for antibacterial and corrosion resistance applications

    Science.gov (United States)

    Krishnadevi, Krishnamoorthy; Selvaraj, Vaithilingam

    2016-03-01

    The mild steel surface has been modified to impart anticorrosion and antibacterial properties through a dip coating method followed by thermal curing of a mixture containing amine terminated cyclotriphosphazene and functionalized titanium dioxide nanoparticles reinforced benzoxazine based cyanate ester composite (ATCP/FTiO2/Bz-CE). The corrosion resistance behavior of coating material has been investigated by electrochemical and antibacterial studies by disc diffusion method. The nanocomposites coated mild steels have displayed a good chemical stability over long immersion in a corrosive environment. The protection efficiency has found to be high for ATCP/FTiO2/Bz-CE composites, which can be used in microelectronics and marine applications.

  2. Impact of oils and coatings on adhesion of structural adhesives

    OpenAIRE

    Hagström, Marcus

    2015-01-01

    This is a master thesis project conducted for Scania CV AB in collaboration with Swerea Kimab. The purpose is to examine how oils and coatings on the surface affect the adhesion of adhesives. Earlier work done by Scania indicate that the amount of oil applied may have an impact on the adhesion. Substrates tested are hot dipped galvanised steel, electro galvanised. AlSi and ZnMg. Oils used are Anticorit RP 3802 that is an anti-corrosive oil and Renoform 3802 that is a drawing oil. The two adhes...

  3. Preparation Technology and Performances of Zn-Cr Coating on Sintered NdFeB Permanent Magnet

    Institute of Scientific and Technical Information of China (English)

    Yu Shengxue; Chen Ling

    2006-01-01

    Zn-Cr coating was prepared on the surface of sintered NdFeB permanent magnet samples and preparation parameters were established.The anticorrosive property of Zn-Cr coating on NdFeB was studied by whole-immersion test in NaCl solution and compared with that of zinc plating and nickel plating on NdFeB.Open-circuit potential and self-corrosion current of NdFeB samples with and without Zn-Cr coating were measured.The micro-morphology and composition of Zn-Cr coating were analyzed through SEM, XPS, EDS and XRD.The effect of Zn-Cr coating on magnetic property of NdFeB magnet was also investigated.It is exposed that Zn-Cr coating is anodic type coating for NdFeB magnet, and provided substrate electrochemical protection, barrier protection and passivation protection.The anticorrosion property of NdFeB magnet is obviously enhanced by Zn-Cr coating while the magnet property of NdFeB magnet changed little.

  4. 农村电网接地引下线腐蚀机理及新型防腐措施%Research on Corrosion Mechanism of Grounding Down Lead Lines and New Anti-corrosion Measures of Rural Power Grid

    Institute of Scientific and Technical Information of China (English)

    郑志生; 钟铭声; 龚庆武

    2015-01-01

    农村电网覆盖面广,不同的土壤条件、缺乏维护及低成本设备缺陷造成农村电网接地引下线腐蚀问题严重。而接地引下线的腐蚀有着不同于接地网的腐蚀机理,即多种环境与化学作用的综合体现,所以农村电网接地引下线需要新的防腐措施。通过对已有研究成果探究,本文提出了包覆法结合牺牲阳极法的农村电网接地引下线防腐新措施,并对其实现进行了论述。%There exists problems in the wide rural power grid that the different soil conditions ,lack of maintenance and low cost e‐quipment defects cause serious corrosion of grounding down lead lines ,which has various mechanisms to the corrosion of grounding grids .The corrosion of grounding down lead lines is a comprehensive reflection of a variety of environmental and chemical interac‐tions ,therefore ,new anti-corrosion measures is required for the grounding down lead lines in the rural power grid .By exploring the existing research results ,new anti-corrosion measures using coating method and sacrificial anode protection method for the grounding down lead lines in the rural power grid is proposed in this paper ,and its realization is described .

  5. Crash-Induced Vibration and Safety Assessment of Breakaway-Type Post Structures Made of High Anticorrosion Steels

    Directory of Open Access Journals (Sweden)

    Sang-Youl Lee

    2016-01-01

    Full Text Available This study deals with car crash effects and passenger safety assessment of post structures with breakaway types using high performance steel materials. To disperse the impact force when a car crashes into a post, the post could be designed with a breakaway feature. In this study, we used a new high anticorrosion steel for the development of advanced breakaways. Based on the improved Cowper-Symonds model, specific physical properties to the high anticorrosion steel were determined. In particular, the complex mechanism of breakaways was studied using various parameters. The parametric studies are focused on the various effects of car crash on the structural performance and passenger safety of breakaway-type posts. The combined effects of using different steel materials on the dynamic behavers are also investigated.

  6. Highly efficient visible light induced photoelectrochemical anticorrosion for 304 SS by Ni-doped TiO2

    International Nuclear Information System (INIS)

    Ni-doped TiO2, which was fabricated via sol–gel method in the present work, possesses the best photoelectrochemical anticorrosion property for 304 stainless steel under visible light illumination when the Ni doping amount is 0.5% (Ti0.995Ni0.005O2). The Ni-doping leads to the extension of the photoresponse of TiO2 from ultraviolet to visible light. Ni is substitutionally doped in TiO2 matrix by substituting the Ti4+ lattice sites and the oxygen vacancy forms for Ti0.995Ni0.005O2. The oxygen vacancy promotes the transfer of photoinduced electrons, resulting in the increase of the photo-to-current conversion efficiency of TiO2 under visible light. Finally, the oxygen vacancy and Ni-doping efficiently enhance the photoelectrochemical anticorrosion property of TiO2 under visible light illumination

  7. Aminobenzoate modified MgAl hydrotalcites as a novel smart additive of reinforced concrete for anticorrosion applications

    NARCIS (Netherlands)

    Yang, Z.; Fischer, H.R.; Cerezo, J.; Mol, J.M.C.; Polder, R.B.

    2013-01-01

    A carbonate form of MgAl hydrotalcite, Mg(2)Al-CO3 and its p-aminobenzoate (pAB) modified derivative, Mg(2)Al-pAB, were synthesized and characterized by means of XRD, FT-IR and TG/DSC. The anticorrosion behavior of Mg(2)Al-pAB was evaluated based on open circuit potential (OCP) of carbon steel in si

  8. Preparations and properties of anti-corrosion additives of water-soluble metal working fluids for aluminum alloy materials.

    Science.gov (United States)

    Watanabe, Shoji

    2008-01-01

    This short review describes various types of anti-corrosion additives of water-soluble metal working fluids for aluminum alloy materials. It is concerned with synthetic additives classified according to their functional groups; silicone compounds, carboxylic acids and dibasic acids, esters, Diels-Alder adducts, various polymers, nitrogen compounds, phosphoric esters, phosphonic acids, and others. Testing methods for water-soluble metal working fluids for aluminum alloy materials are described for a practical application in a laboratory. PMID:18075217

  9. Assessment of Automotive Coatings Used on Different Metallic Substrates

    Directory of Open Access Journals (Sweden)

    W. Bensalah

    2014-01-01

    Full Text Available Four epoxy primers commonly used in the automotive industry were applied by gravity pneumatic spray gun over metallic substrates, specifically, steel, electrogalvanized steel, hot-dip galvanized steel, and aluminum. A two-component polyurethane resin was used as topcoat. To evaluate the performance of the different coating systems, the treated panels were submitted to mechanical testing using Persoz hardness, impact resistance, cupping, lattice method, and bending. Tribological properties of different coating systems were conducted using pin on disc machine. Immersion tests were carried out in 5% NaCl and immersion tests in 3% NaOH solutions. Results showed which of the coating systems is more suitable for each substrate in terms of mechanical, tribological, and anticorrosive performance.

  10. Degradation behavior of n-MAO/EPD bio-ceramic composite coatings on magnesium alloy in simulated body fluid

    International Nuclear Information System (INIS)

    Highlights: • A bio-ceramic n-MAO/EPD coating was prepared by combined MAO and EPD technique. • The precipitates of Ca/P compound are formed on the surface samples during immersion. • The n-MAO/EPD coating with HA dense structure has a favorable anti-corrosion effect. • Two degradation mechanism models for the n-MAO and n-MAO/EPD coating were proposed. - Abstract: The bio-ceramic composite coatings have been fabricated on ZK60 magnesium (Mg) alloy to improve its bio-corrosion resistance in a simulated body fluid (SBF). Firstly, micro-arc oxidation coatings (n-MAO coating) with the addition of zirconium oxide (ZrO2) and cerium oxide (CeO2) nano-particles were prepared by MAO technique on ZK60Mg alloy in alkaline electrolyte. Secondly, nano-hydroxyapatite (HA) was deposited on the surface of n-MAO coatings by using electrophoretic deposition (EPD) technique. The degradation behavior of the coated samples was investigated by means of immersion tests and electrochemical impedance spectroscopy (EIS) in the SBF at 36.5 ± 0.5 °C. The variation of phase composition, surface and cross-section morphology of coatings at different immersion stages were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The results showed that the precipitation layer with biological activity formed on the surface of coated samples during the SBF immersion, which can inhibit Mg alloys from degrading effectively. The n-MAO/EPD composite coating with HA dense structure has a favorable anti-corrosion effect compared to the n-MAO coating. Degradation mechanism model of the corrosion process at different corrosion stages for two kinds of coatings were proposed. The long-term corrosion protection of the n-MAO/EPD composite coating was governed significantly by the synergistic effect of phase composition stability and micro structural integrity

  11. Degradation behavior of n-MAO/EPD bio-ceramic composite coatings on magnesium alloy in simulated body fluid

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Ying, E-mail: yxiong@zjut.edu.cn [College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310032 (China); Lu, Chao [College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310032 (China); Wang, Chao; Song, Renguo [School of Materials Science and Engineering, Changzhou University, Changzhou 213164 (China); Jiangsu Key Laboratory of Materials Surface Science and Technology, Changzhou University, Changzhou 213164 (China)

    2015-03-15

    Highlights: • A bio-ceramic n-MAO/EPD coating was prepared by combined MAO and EPD technique. • The precipitates of Ca/P compound are formed on the surface samples during immersion. • The n-MAO/EPD coating with HA dense structure has a favorable anti-corrosion effect. • Two degradation mechanism models for the n-MAO and n-MAO/EPD coating were proposed. - Abstract: The bio-ceramic composite coatings have been fabricated on ZK60 magnesium (Mg) alloy to improve its bio-corrosion resistance in a simulated body fluid (SBF). Firstly, micro-arc oxidation coatings (n-MAO coating) with the addition of zirconium oxide (ZrO{sub 2}) and cerium oxide (CeO{sub 2}) nano-particles were prepared by MAO technique on ZK60Mg alloy in alkaline electrolyte. Secondly, nano-hydroxyapatite (HA) was deposited on the surface of n-MAO coatings by using electrophoretic deposition (EPD) technique. The degradation behavior of the coated samples was investigated by means of immersion tests and electrochemical impedance spectroscopy (EIS) in the SBF at 36.5 ± 0.5 °C. The variation of phase composition, surface and cross-section morphology of coatings at different immersion stages were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The results showed that the precipitation layer with biological activity formed on the surface of coated samples during the SBF immersion, which can inhibit Mg alloys from degrading effectively. The n-MAO/EPD composite coating with HA dense structure has a favorable anti-corrosion effect compared to the n-MAO coating. Degradation mechanism model of the corrosion process at different corrosion stages for two kinds of coatings were proposed. The long-term corrosion protection of the n-MAO/EPD composite coating was governed significantly by the synergistic effect of phase composition stability and micro structural integrity.

  12. Mechanical and corrosion resistance properties of TiO2 nanoparticles reinforced Ni coating by electrodeposition

    International Nuclear Information System (INIS)

    Coatings have been widely used in engineering and decoration to protect components and products and enhance their life span. Nickel (Ni) is one of the most important hard coatings. Improvement in its tribological and mechanical properties would greatly enhance its use in industry. Nanocomposite coatings of metals with various reinforced nanoparticles have been developed in last few decades. Titania (TiO2) exhibit excellent mechanical properties. It is believed that TiO2 incorporation in Ni matrix will improve the properties of Ni coatings significantly. The main purpose of the current work is to investigate the mechanical and anti-corrosion properties of the electroplated nickel nanocomposite with a small percentage of TiO2. The surface morphology of nanocomposite coating was characterized by scanning electron microscopy (SEM). The hardness of the nanocoating was carried out using micromaterials nanoplatform. The sliding wear rate of the coating at room temperature in dry condition was assessed by a reciprocating ball-on-disk computer-controlled oscillating tribotester. The results showed the nanocomposite coatings have a smoother and more compact surface than the pure Ni layer and have higher hardness and lower wear rate than the pure Ni coating. The anti-corrosion property of nanocomposite coating was carried out in 3.5% NaCl and high concentrated 35% NaCl solution, respectively. The results also showed that the nanocomposite coating improves the corrosion resistance significantly. This present work reveals that incorporation of TiO2 in nickel nanocomposite coating can achieve improved corrosion resistance and mechanical properties of both hardness and wear resistance performances, and the improvement becomes stronger as the content of TiO2 is increased.

  13. Mechanical and corrosion resistance properties of TiO2 nanoparticles reinforced Ni coating by electrodeposition

    Science.gov (United States)

    Shao, W.; Nabb, D.; Renevier, N.; Sherrington, I.; Luo, J. K.

    2012-09-01

    Coatings have been widely used in engineering and decoration to protect components and products and enhance their life span. Nickel (Ni) is one of the most important hard coatings. Improvement in its tribological and mechanical properties would greatly enhance its use in industry. Nanocomposite coatings of metals with various reinforced nanoparticles have been developed in last few decades. Titania (TiO2) exhibit excellent mechanical properties. It is believed that TiO2 incorporation in Ni matrix will improve the properties of Ni coatings significantly. The main purpose of the current work is to investigate the mechanical and anti-corrosion properties of the electroplated nickel nanocomposite with a small percentage of TiO2. The surface morphology of nanocomposite coating was characterized by scanning electron microscopy (SEM). The hardness of the nanocoating was carried out using micromaterials nanoplatform. The sliding wear rate of the coating at room temperature in dry condition was assessed by a reciprocating ball-on-disk computer-controlled oscillating tribotester. The results showed the nanocomposite coatings have a smoother and more compact surface than the pure Ni layer and have higher hardness and lower wear rate than the pure Ni coating. The anti-corrosion property of nanocomposite coating was carried out in 3.5% NaCl and high concentrated 35% NaCl solution, respectively. The results also showed that the nanocomposite coating improves the corrosion resistance significantly. This present work reveals that incorporation of TiO2 in nickel nanocomposite coating can achieve improved corrosion resistance and mechanical properties of both hardness and wear resistance performances, and the improvement becomes stronger as the content of TiO2 is increased.

  14. Structural properties of new siliconized coatings formed by pyrolytic decomposition of pure TPOS

    Science.gov (United States)

    Hashem, Khaled M. E.; Abo-Elenien, O. M.

    1999-09-01

    New anticorrosion siliconized coatings are formed by pyrolytic decomposition of sprayed pure tetraphenoxy silane (TPOS) on surfaces of carbon steel specimens, in a preheated furnace within a temperature range 500-650°C. The optimum conditions for developing highly corrosion resistant siliconized coatings, are decided by the aids of structural and composition analysis techniques. By the aid of EDXRF, SEM, Ultra Sonic Cleaner (USV), cross-edged SEM micrographs, O.M. and Thin Film On Surface (TFOS) software program, the optimal thickness, structure free voids interface and maximum adhesion properties of the produced siliconized coatings, were determined at 600°C for pyrolytical time 45 min. Evaluation of the coatings' composition yielding a high anticorrosion property is fully detailed by the aid of XRD analysis, electrochemical dissolution in different acidic media and adhesion techniques. The microstructure of the optimum siliconized coatings is regular in shape, size, orientation and boundaries of the formed bulky aggregated particles. Also the striations around the coatings' particles are mostly narrow. The strong adhesion property of the coating/metal surface interface, is assessed on the basis of the `go, no go' principle and is related to the inner diffusion of silica (rooting phenomenon). The variation in the constituents' ratios of the produced coatings at different temperatures is attributed to the rate of interconversion of the microcrystallite SiO 2 to crystalline phases and rate of interaction between the diffused iron, Fe 2+, and the crystalline phases of SiO 2. Electrochemical dissolution performance for uncoated and coated electrodes in the range of 0.1-10 M HCl solutions reveal that no significant corrosion behavior is observed. However, the variation between anodic and cathodic routes, is referred to the formation of strong passive irreversible phases on the electrode's surface. These phases could initiate from metal ions (Fe 2+) either provided by

  15. Electrosynthesis and analytical characterization of PMMA coatings on titanium substrates as barriers against ion release.

    Science.gov (United States)

    De Giglio, E; Cometa, S; Sabbatini, L; Zambonin, P G; Spoto, G

    2005-02-01

    The performance of polyacrylic coatings as barrier films against corrosion of titanium-based orthopaedic implants was investigated. In particular, poly(methyl methacrylate) (PMMA) was electrosynthesized on titanium substrates by electro-reductive processes from aqueous monomer solutions. The obtained PMMA coatings were characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The effect of an annealing treatment on the morphology of coatings with respect to uniformity and porosity of films was assessed by scanning electron microscopy (SEM). An inductively coupled plasma-mass spectrometry (ICP-MS) technique was used for ion concentration measurements in ion release tests performed on TiAlV sheets modified with PMMA coatings (annealed and unannealed). Results indicated that the annealing process produces coatings with considerable anticorrosion performances. PMID:15657712

  16. Ag-Incorporated FHA Coating on Pure Mg: Degradation and in Vitro Antibacterial Properties.

    Science.gov (United States)

    Zhao, Changli; Hou, Peng; Ni, Jiahua; Han, Pei; Chai, Yimin; Zhang, Xiaonong

    2016-03-01

    Fluoridated hydroxyapatite (FHA) coating can help retard the degradation of magnesium, and possess good biocompatibility. However, the antibacterial property of FHA is very limited. In this work, we aimed to incorporate silver into FHA structure to fabricate biocompatible and antibacterial coatings with enhanced anticorrosion property. The results showed that the Ag-FHA coating prepared by electrochemical deposition and subsequent immersion in AgNO3 solution was superior to the Ag-FHA coating prepared by coelectrodeposition in terms of crystal structure, surface morphology and corrosion resistance. The release of Ag(+) ion causing high antiplanktonic bacterial rate and excellent antiadherence property to MRSA. Meanwhile, good cell compatibility of MC3T3-E1 including cell viability, cell adhesion, and cell morphology was achieved under the controlled degradation. The balance of degradation and antimicrobial property of Ag-incorporated FHA coating made it an alternative in the application of surface modification for biodegradable Mg. PMID:26855088

  17. Exposure Test on Two Surface Anticorrosion Technologies for Marine Concrete Structure

    OpenAIRE

    Yang, Haicheng; Xiong, Jianbo; Su, Quanke; Yan, Yu

    2014-01-01

    This paper is to study the effect of surface coating and silane hydrophobic agents for high performance concrete durability in a marine environment of tidal zone and splash zone by exposure test in JiaoZhou Bay. The results indicated that surface coating had good protection and coating quality after a 5-year period and the adhesive strength with concrete surface was more than 2.5 MPa. Surface coating can effectively improve chloride ion penetration resistance of concrete structures. The subst...

  18. Hydrogen–argon plasma pre-treatment for improving the anti-corrosion properties of thin Al{sub 2}O{sub 3} films deposited using atomic layer deposition on steel

    Energy Technology Data Exchange (ETDEWEB)

    Härkönen, Emma, E-mail: emma.harkonen@helsinki.fi [Laboratory of Inorganic Chemistry, Department of Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 Helsinki (Finland); Potts, Stephen E.; Kessels, Wilhelmus M.M. [Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Díaz, Belén; Seyeux, Antoine; Światowska, Jolanta; Maurice, Vincent; Marcus, Philippe [Chimie ParisTech, Laboratoire de Physico-Chimie des Surfaces (LPCS), 11 Rue Pierre et Marie Curie, F-75005 Paris (France); CNRS UMR 7045, 11 Rue Pierre et Marie Curie, F-75005 Paris (France); Radnóczi, György; Tóth, Lajos [Research Centre for Natural Sciences HAS, MTA TKK, Budapest (Hungary); Kariniemi, Maarit; Niinistö, Jaakko; Ritala, Mikko [Laboratory of Inorganic Chemistry, Department of Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 Helsinki (Finland)

    2013-05-01

    The effect of H{sub 2}–Ar plasma pre-treatment prior to thermal atomic layer deposition (ALD) and plasma-enhanced atomic layer deposition (PEALD) of Al{sub 2}O{sub 3} films on steel for corrosion protection was investigated. Time-of-flight secondary ion mass spectrometry and transmission electron microscopy were used to observe the changes in the interface. The electrochemical properties of the samples were studied with polarization measurements, and the coating porosities were calculated from the polarization results for easier comparison of the coatings. Prior to thermal ALD the plasma pre-treatment was observed to reduce the amount of impurities at the interface and coating porosity by 1–3 orders of magnitude. The anti-corrosion properties of the PEALD coatings could also be improved by the pre-treatment. However, exposure of the pre-treatment plasma activated steel surface to oxygen plasma species in PEALD led to facile oxide layer formation in the interface. The oxide layer formed this way was thicker than the native oxide layer and appeared to be detrimental to the protective properties of the coating. The best performance for PEALD Al{sub 2}O{sub 3} coatings was achieved when, after the plasma pre-treatment, the surface was given time to regrow a thin protective interfacial oxide prior to exposure to the oxygen plasma. The different effects that thermal and plasma-enhanced ALD have on the substrate-coating interface were compared. The reactivity of the oxygen precursor was shown to have a significant influence on substrate surface in the early stages of film growth and thereafter also on the overall quality of the protective film. - Highlights: • Influence of H{sub 2}–Ar plasma pre-treatment to ALD coatings on steel was studied. • The pre-treatment modified the coating–substrate interface composition and thickness. • The pre-treatment improved the barrier properties of the coatings.

  19. Effect of Bath ph on Electroless Ni-P Coating Deposited on Open-Cell Aluminum Foams

    Science.gov (United States)

    Liu, Jiaan; Si, Fujian; Li, Dong; Liu, Yan; Cao, Zheng; Wang, Guoyong

    2015-09-01

    Different electroless Ni-P coatings were deposited on open-cell aluminum foams at various bath pH. The effect of bath pH on the morphology, structure, components, phases and corrosion resistance of the Ni-P coating was studied by scanning electron microscopy (SEM), confocal laser scanning microscope (CLSM), energy-dispersive spectroscopy (EDS), X-ray diffraction (XRD), immersion test and electrochemical polarization measurement, respectively. The experimental results show that the bath pH not only changed the reactivity of the bath, but also had a influence on the microstructure and anticorrosive property of electroless Ni-P coating. The high pH bath raises the thickness of Ni-P coating but decreases the content of phosphorus element in the Ni-P coating. The corrosion resistance of the coated aluminum foams increases when the bath pH rises.

  20. Deposition of electroless Ni-P/Ni-W-P duplex coatings on AZ91D magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The electroless Ni-P/Ni-W-P duplex coatings were deposited directly on AZ91D magnesium alloy by all acid-sulfate nickel bath.Nickel suitIhate and sodium tungstate were used as metal ion sources and sodium hypophosphite was used as reducing agent.The coating was characterized for its structure,morphologies,microhardness and corrosion properties.The presence of dense and coarse nodules in the duplex coatings Was observed by SEM and EDS.Tungsten content in Ni-P/Ni-W-P alloy is about 0.65%(mass fraction)and the phosphorus content is 8.1 8%(mass fraction).The microhardness of the coatings is 622 VHN.The coating shows good adhesion to the substrate.The results of electrochemical analysis,the porosity and the immersion test show that Ni-P/Ni-W-P duplex coatings possess noble anticorrosion properties to protect the AZ91D magnesium alloy.

  1. Graphene/Epoxy Coating as Multifunctional Material for Aircraft Structures

    Directory of Open Access Journals (Sweden)

    Tullio Monetta

    2015-06-01

    Full Text Available Recently, the use of graphene as a conductive nanofiller in the preparation of inorganic/polymer nanocomposites has attracted increasing interest in the aerospace field. The reason for this is the possibility of overcoming problems strictly connected to the aircraft structures, such as electrical conductivity and thus lightning strike protection. In addition, graphene is an ideal candidate to enhance the anti-corrosion properties of the resin, since it absorbs most of the light and provides hydrophobicity for repelling water. An important aspect of these multifunctional materials is that all these improvements can be realized even at very low filler loadings in the polymer matrix. In this work, graphene nanoflakes were incorporated into a water-based epoxy resin, and then the hybrid coating was applied to Al 2024-T3 samples. The addition of graphene considerably improved some physical properties of the hybrid coating as demonstrated by Electrochemical Impedance Spectroscopy (EIS analysis, ameliorating anti-corrosion performances of raw material. DSC measurements and Cross-cut Test showed that graphene did not affect the curing process or the adhesion properties. Moreover, an increment of water contact angle was displayed.

  2. Polypropylene Glycol-Silver Nanoparticle Composites: A Novel Anticorrosion Material for Aluminum in Acid Medium

    Science.gov (United States)

    Solomon, Moses M.; Umoren, Saviour A.; Israel, Aniekemeabasi U.; Ebenso, Eno E.

    2015-11-01

    Admixture of polypropylene glycol and 1 mM AgNO3 together with natural honey as reducing and stabilizing agent was employed to prepare in situ polypropylene glycol/silver nanoparticle (PPG/AgNPs) composite. The prepared PPG/AgNPs composite was characterized by UV-Vis spectroscopy, FTIR, XRD, and EDS, while the morphology of the Ag nanoparticles in the composite was obtained by TEM. TEM results revealed that the Ag nanoparticles were spherical in shape. The anticorrosion property of PPG/AgNPs composite was examined by electrochemical, weight loss, SEM, EDS, and water contact angle measurements. Results obtained show that PPG/AgNPs are effective in retarding the dissolution of Al in an acid-induced corrosive environment. Inhibition efficiency increased with the increasing composite concentration but decreased with the increasing temperature. Potentiodynamic polarization results revealed that PPG/AgNPs functions as a mixed-type corrosion inhibitor. The adsorption of the composite onto Al surface was found to follow El-Awady et al. adsorption isotherm model. SEM, EDS, and water contact angle results confirmed the adsorption of PPG/AgNPs films onto Al surface.

  3. A superhydrophilic nitinol shape memory alloy with enhanced anti-biofouling and anti-corrosion properties.

    Science.gov (United States)

    Song, K; Min, T; Jung, J-Y; Shin, D; Nam, Y

    2016-05-01

    This work reports on a nitinol (NiTi) surface modification scheme based on a chemical oxidation method, and characterizes its effects on wetting, biofouling and corrosion. The scheme developed is also compared with selected previous oxidation methods. The proposed method turns NiTi into superhydrophilic in ~5 min, and the static contact angle and contact angle hysteresis were measured to be ~7° and ~12°, respectively. In the PRP (platelet rich plasma) test, platelet adhesion was reduced by ~89% and ~77% respectively, compared with the original NiTi and the NiTi treated with the previous chemical oxidation scheme. The method developed provides a high (~1.1 V) breakdown voltage, which surpasses the ASTM standard for intervascular medical devices. It also provides higher superhydrophilicity, hemo-compatibility and anti-corrosion resistance than previous oxidation schemes, with a significantly reduced process time (~5 min), and will help the development of high performance NiTi devices. PMID:27021115

  4. Analytical investigations of poly(acrylic acid) coatings electrodeposited on titanium-based implants: a versatile approach to biocompatibility enhancement.

    Science.gov (United States)

    De Giglio, E; Cometa, S; Cioffi, N; Torsi, L; Sabbatini, L

    2007-12-01

    A polyacrylic acid film was synthesized on titanium substrates from aqueous solutions via an electroreductive process for the first time. This work was done in order to develop a versatile coating for titanium-based orthopaedic implants that acts as both an effective bioactive surface and an effective anti-corrosion barrier. The chemical structure of the PAA coating was investigated by X-ray photoelectron spectroscopy (XPS). Scanning electron microscopy (SEM) was employed to evaluate the effect of annealing treatment on the morphology of the coatings in terms of their uniformity and porosity. Inductively coupled plasma mass spectrometry was used to measure ion concentrations in ion release tests performed on Ti-6Al-4V sheets modified with PAA coatings (annealed and unannealed). Results indicate that the annealing process produces coatings that possess considerable anti-corrosion performance. Moreover, the availability and the reactivity of the surface carboxylic groups were exploited in order to graft biological molecules onto the PAA-modified titanium implants. The feasibility of the grafting reaction was tested using a single aminoacid residue. A fluorinated aminoacid was selected, and the grafting reaction was monitored both by XPS, using fluorine as a marker element, and via quartz crystal microbalance (QCM) measurements. The success of the grafting reaction opens the door to the synthesis of a wide variety of PAA-based coatings that are functionalized with selected bioactive molecules and promote positive reactions with the biological system interfacing the implant while considerably reducing ion release into surrounding tissues. PMID:17516054

  5. Cholesteryl-coated carbonyl iron particles with improved anti-corrosion stability and their viscoelastic behaviour under magnetic field

    Czech Academy of Sciences Publication Activity Database

    Mrlik, M.; Ilčíková, M.; Sedlačík, M.; Mosnáček, J.; Peer, Petra; Filip, Petr

    2014-01-01

    Roč. 292, č. 9 (2014), s. 2137-2143. ISSN 0303-402X R&D Projects: GA ČR(CZ) GP14-32114P Grant ostatní: GA MŠk(CZ) ED2.1.00/03.0111 Institutional support: RVO:67985874 Keywords : carbonyl iron * cholesteryl chloroformate * silicone oil suspensions * viscoelasticity * magnetorheology Subject RIV: BK - Fluid Dynamics Impact factor: 1.865, year: 2014

  6. Development of Castor Oil Based Poly(urethane-esteramide)/TiO2 Nanocomposites as Anticorrosive and Antimicrobial Coatings

    OpenAIRE

    Mohammed Rafi Shaik; Manawwer Alam; Naser M. Alandis

    2015-01-01

    Castor oil based polyesteramide (CPEA) resin has been successfully synthesized by the condensation polymerization of N-N-bis (2-hydroxyethyl) castor oil fatty amide (HECA) with terephthalic acid and further modified with different percentages of 7, 9, 11, and 13 wt.% of toluene-2,4-diisocyanate (TDI) to obtain poly(urethane-esteramide) (UCPEA), via addition polymerization. TiO2 (0.1, 0.2, 0.3, 0.4, and 0.5 wt%) nanoparticles were dispersed in UCPEA resin. The structural elucidation of HECA, C...

  7. Electrophoretic deposition and electrochemical behavior of novel graphene oxide-hyaluronic acid-hydroxyapatite nanocomposite coatings

    Science.gov (United States)

    Li, Ming; Liu, Qian; Jia, Zhaojun; Xu, Xuchen; Shi, Yuying; Cheng, Yan; Zheng, Yufeng; Xi, Tingfei; Wei, Shicheng

    2013-11-01

    Novel ternary graphene oxide-hyaluronic acid-hydroxyapatite (GO-HY-HA) nanocomposite coatings were prepared on Ti substrate using anodic electrophoretic deposition (EPD). Hyaluronic acid was employed as charging additive and dispersion agent during EPD. The kinetics and mechanism of the deposition, and the microstructure of the coated samples were investigated using scanning electron microscopy, X-ray diffraction, Raman spectrum, thermo-gravimetric analysis, and microscopic Fourier transform infrared analysis. The results showed that the addition of GO sheets into the HY-HA suspensions could increase the deposition rate and inhibit cracks creation and propagation in the coatings. The corrosion resistant of the resulting samples were evaluated using potentiodynamic polarization method in simulated body fluid, and the GO-HY-HA coatings could effectively improve the anti-corrosion property of the Ti substrate.

  8. Electrophoretic deposition and electrochemical behavior of novel graphene oxide-hyaluronic acid-hydroxyapatite nanocomposite coatings

    International Nuclear Information System (INIS)

    Novel ternary graphene oxide-hyaluronic acid-hydroxyapatite (GO-HY-HA) nanocomposite coatings were prepared on Ti substrate using anodic electrophoretic deposition (EPD). Hyaluronic acid was employed as charging additive and dispersion agent during EPD. The kinetics and mechanism of the deposition, and the microstructure of the coated samples were investigated using scanning electron microscopy, X-ray diffraction, Raman spectrum, thermo-gravimetric analysis, and microscopic Fourier transform infrared analysis. The results showed that the addition of GO sheets into the HY-HA suspensions could increase the deposition rate and inhibit cracks creation and propagation in the coatings. The corrosion resistant of the resulting samples were evaluated using potentiodynamic polarization method in simulated body fluid, and the GO-HY-HA coatings could effectively improve the anti-corrosion property of the Ti substrate

  9. Investigation of hexagonal boron nitride as an atomically thin corrosion passivation coating in aqueous solution

    Science.gov (United States)

    Zhang, Jing; Yang, Yingchao; Lou, Jun

    2016-09-01

    Hexagonal boron nitride (h-BN) atomic layers were utilized as a passivation coating in this study. A large-area continuous h-BN thin film was grown on nickel foil using a chemical vapor deposition method and then transferred onto sputtered copper as a corrosion passivation coating. The corrosion passivation performance in a Na2SO4 solution of bare and coated copper was investigated by electrochemical methods including cyclic voltammetry (CV), Tafel polarization and electrochemical impedance spectroscopy (EIS). CV and Tafel analysis indicate that the h-BN coating could effectively suppress the anodic dissolution of copper. The EIS fitting result suggests that defects are the dominant leakage source on h-BN films, and improved anti-corrosion performances could be achieved by further passivating these defects.

  10. Corrosion Resistance of Electroless Ni-Cu-P Ternary Alloy Coatings in Acidic and Neutral Corrosive Mediums

    Directory of Open Access Journals (Sweden)

    Mbouillé Cissé

    2010-01-01

    Full Text Available Electroless Ni-Cu-P alloy coatings were deposited on the ordinary steel substrate in an acidic hypophosphite-type plating bath. These coatings were characterized by a scanning electron microscope (SEM and an X-ray diffraction. The micrograph shows that coating presents a nodular aspect and is relatively homogeneous and very smooth. The EDX analysis shows that the coating contains 12 wt.% of phosphorus element with a predominance of nickel element. In addition, the anticorrosion properties of the Ni-Cu-P coatings in 1 M HCl, 1 M H2SO4, and 3% NaCl solutions were investigated using Tafel polarization curves, electrochemical impedance spectroscopy, and SEM/EDX analysis. The result showed a marginal improvement in corrosion resistance in 3% NaCl solution compared to acidic medium. It also showed that the corrosion mechanism depends on the nature of the solution.

  11. HIGH-PERFORMANCE COATING MATERIALS

    Energy Technology Data Exchange (ETDEWEB)

    SUGAMA,T.

    2007-01-01

    Corrosion, erosion, oxidation, and fouling by scale deposits impose critical issues in selecting the metal components used at geothermal power plants operating at brine temperatures up to 300 C. Replacing these components is very costly and time consuming. Currently, components made of titanium alloy and stainless steel commonly are employed for dealing with these problems. However, another major consideration in using these metals is not only that they are considerably more expensive than carbon steel, but also the susceptibility of corrosion-preventing passive oxide layers that develop on their outermost surface sites to reactions with brine-induced scales, such as silicate, silica, and calcite. Such reactions lead to the formation of strong interfacial bonds between the scales and oxide layers, causing the accumulation of multiple layers of scales, and the impairment of the plant component's function and efficacy; furthermore, a substantial amount of time is entailed in removing them. This cleaning operation essential for reusing the components is one of the factors causing the increase in the plant's maintenance costs. If inexpensive carbon steel components could be coated and lined with cost-effective high-hydrothermal temperature stable, anti-corrosion, -oxidation, and -fouling materials, this would improve the power plant's economic factors by engendering a considerable reduction in capital investment, and a decrease in the costs of operations and maintenance through optimized maintenance schedules.

  12. An investigation of coated aluminium bipolar plates for PEMFC

    International Nuclear Information System (INIS)

    Highlights: ► Coated aluminium bipolar plates demonstrate the hydrophobic property than the raw material. ► The corrosion behaviour of bipolar plate decreases the PEMFC performance severely. ► These PEMFCs are measured by current–voltage (I–V) curve test. ► The oxide film increases the interfacial contact resistance. -- Abstract: The performance of Al-alloy bipolar plates for the PEMFC (proton exchange membrane fuel cell) system is investigated in this paper. The metallic bipolar plates are modified with a Ni–P coating. The performance of the Al-alloy bipolar plates is evaluated by the coating structure, corrosion resistance, contact angle and single cell performance. The results indicate that the coated aluminium bipolar plates demonstrate hydrophobic and anti-corrosive properties. The hydrophobic property increases the contact angle on the surface from 46.08° to 80.51°. Meanwhile, the corrosion rate of the Ni–P coating can be over 1 order of magnitude lower than that of the substrate. Hence, the substrate with the coating maintains superior performance under the long term test. The present study proves that both the hydrophobicity and corrosion resistance significantly affect the metallic bipolar plate.

  13. Sem-edx and ftir studies of chlorinated rubber coating

    International Nuclear Information System (INIS)

    Summary: Anticorrosive performance of chlorinated rubber coating has been investigated by visual examination, Scanning electron microscopy (SEM)/Energy dispersive X-ray (EDX) analysis and Fourier transform infrared (FTIR) spectroscopy. After surface preparation, commercially available coating system based on chlorinated rubber (primer)/chlorinated rubber (topcoat) formulation was applied on mild steel test panels (10cm x 15cm sizes). Prepared coated panels were exposed at marine, industrial and urban test sites located in Karachi, Pakistan according to ISO 8565 norm. Accelerated testing was performed by using a salt spray chamber (ASTM B117 norm). Accelerated weathering methods are the methods in which the factors responsible for the degradation of coatings are artificially intensified in order to achieve the rapid degradation of coatings. Visual examination of blistering and rusting as well as SEM micrographs indicated a more severe degradation of the coating surface characteristics at natural exposure testing sites (particularly at marine test site) than for accelerated (salt spray) testing. EDX determination of the Oxygen/Carbon (O/C) ratios also indicated increased degradation at natural test sites compared to the accelerated (salt spray) testing. Photooxidation of the binder results in the formation of carbonyl compounds as revealed by FTIR spectroscopy which also indicated dehydrochlorination. (author)

  14. Microstructure and corrosion behavior of electroless deposited Ni-P/CeO2 coating

    Institute of Scientific and Technical Information of China (English)

    Hui Ming Jin; Shi Hang Jiang; Lin Nan Zhang

    2008-01-01

    Electroless Ni-P/nano-CeO2 composite coating was prepared in acidic condition,and its microstructure and corrosive property were compared with its CeO2-free counterpart.Scanning electronic microscopy (SEM) and X-ray diffraction (XRD) spectrometer were used to examine surface morphology and structure of the as-plated coating.Differential scanning calorimeter (DSC) and transmission electronic microscopy (TEM) were used to study the coating's phase change at high temperature.The coating's corrosive behavior in 3%NaCI + 5%H2SO4 solution was also investigated.The results showed that Ni-P coating had partial amorphous structure mixed with nano-crystals,while the Ni-P/CeO2 coating had perfect amorphous structure.In high-temperature condition,Ni3P precipitation and Ni crystallization took place in both coatings but at different temperatures,while the Ni-P/CeO2 coating had sintered phase of NiCe2O4 spinels.The anti-corrosion property was better in the CeO2-containing coating,and this was due to its less liability to undergo local-cell corrosion than its CeO2-free counterpart.Ni-P/CeO2 coating's pure amorphous structure was the result of Ni's hindered crystal-typed deposition and P's promoted deposition.

  15. Characterization of steam generated anti-corrosive oxide films on Aluminium alloys

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Jellesen, Morten Stendahl; Ambat, Rajan

    2014-01-01

    hexavalent chromium is strictly regulated due to its toxic nature and suspected carcinogenicity. So, it is highly imperative to develop other alternatives for chrome conversion coatings. Treatment of aluminium with natural water at elevated temperatures results in the formation of different forms of...... converted or transformed into functional conversion coatings in order to enhance corrosion resistance and adhesion to paint systems. Chromium based conversion coatings have been extensively used on aluminium alloys to improve adhesion of subsequent paint layers and corrosion resistance. However, the use of...

  16. Action mechanism of antioxidation and anticorrosion and molecular design for perfluoropolyether fluid additives (I) --Action mechanism of additive and property of donating-accepting electron

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The combination energy and chemical adsorption energy of N-substituted perfluoropoly- alkyletherphenylamide (PFPEA) additive to perfluoropolyalkylether oxygen radical (RfO.) and to Fe atom have been calculated by quantum chemical methods. Structural characteristics, action mechanism, property of donating-accepting electron and substituent effect for antioxidant and anticorrosive additive are investigated. It is found that HOMO of the additives is a p-molecular orbital with lone pair electron of heteroatom. The HOMO of PFPEA additive reacts with LUMO of Fe atom to result in chemical adsorption. The LUMO of additive can interact with the SOMO of RfO. and accept electron of RfO. to form stable addition product. The additives have the property of donating-accepting electron. The electron-releasing group, particularly, the phenyl group, introduced to N atom of phenylamide can increase the combination energy and chemical adsorption energy, and enhance the antioxidant and anticorrosive efficiency. The research achievements can provide useful information for the designing of new antioxidant and anticorrosive additive. Based on the calculated results, antioxidant and anticorrosive efficiency can be predicted roughly as the following order: compounds III>II>I>IV>V.

  17. A New fast-drying Chlorinated Rubber Heavy Anti-corrosion Static Conductive Paint at Room Temperature%室温快干氯化橡胶重防腐导静电涂料

    Institute of Scientific and Technical Information of China (English)

    吕维华; 伍家卫; 张远欣; 赵立祥; 苏晓云

    2011-01-01

    A new heavy anti-corrosion static conductive paint was prepared with chlorinated rubber as its main film forming substance, the homemade high solids content co-polyester resin as toughening resin, conductive graphite modified by silane coupling agent as conductive material. Its formula, manufacturing process and main performance indexes were introduced. The influence of the plasticizers, organic solvents, conductive graphite dosage and coating thickness to properties of the coating was studied. The results showed that the comprehensive performance of the coating was excellent when dosage of the high solids content co-polyester resin was 25 ±5%, conductive graphite 20 ±5%, the thinner of dissolution paint was mix solvents of methylbenzene, acetone, ethyl acetate and butyl acetate. Thermogravimetric analysis showed that heat resistance of coating was improved after adding polyester resin. The SEM images of the coating showed that the morphology was a comparative neat layered dense layer and explained why the coating had an excellent barrier property and corrosion-resistance.%介绍了以氯化橡胶为主要成膜物,自制高固体分聚酯树脂为增韧改性树脂,用硅烷偶联剂处理的导电石墨为导电剂的新型重防腐导静电涂料的配方、制备工艺及主要性能指标;研究了增塑剂和有机溶剂种类、导电石墨用量及涂层厚度对涂料性能的影响;结果表明,聚酯树脂质量分数为25±5%、导电石墨质量分数为20±5%,稀释剂为用甲苯、丙酮、醋酸乙酯和醋酸丁酯配成的混合溶剂时,所得涂层综合性能最佳;热重分析表明,添加聚酯树脂后涂层耐热性提高;扫描电镜图显示,涂层为规则排列的层状致密层,说明涂料具有优良的阻隔性和防腐性.

  18. Final Technical Report - Recovery Act: Organic Coatings as Encapsulants for Low Cost, High Performance PV Modules

    Energy Technology Data Exchange (ETDEWEB)

    Stuart Hellring; Jiping Shao; James Poole

    2011-12-05

    The objective of this project was to evaluate the feasibility of utilizing PPG's commercial organic coatings systems as efficient, modernized encapsulants for low cost, high performance, thin film photovoltaic modules. Our hypothesis was that the combination of an anticorrosive coating with a more traditional barrier topcoat would mitigate many electrochemical processes that are now responsible for the significant portion of photovoltaic (PV) failures, thereby nullifying the extremely high moisture barrier requirements of currently used encapsulation technology. Nine commercially available metal primer coatings and six commercially available top coatings were selected for screening. Twenty-one different primer/top coat combinations were evaluated. The primer coatings were shown to be the major contributor to corrosion inhibition, adhesion, and barrier properties. Two primer coatings and one top coating were downselected for testing on specially-fabricated test modules. The coated test modules passed initial current leakage and insulation testing. Damp Heat testing of control modules showed visible corrosion to the bus bar metal, whereas the coated modules showed none. One of the primer/top coat combinations retained solar power performance after Damp Heat testing despite showing some delamination at the EVA/solar cell interface. Thermal Cycling and Humidity Freeze testing resulted in only one test module retaining its power performance. Failure modes depended on the particular primer/top coating combination used. Overall, this study demonstrated that a relatively thin primer/top coating has the potential to replace the potting film and backsheet in crystalline silicon-based photovoltaic modules. Positive signals were received from commercially available coatings developed for applications having performance requirements different from those required for photovoltaic modules. It is likely that future work to redesign and customize these coatings would result in

  19. Forecasting of durability of waterborne coatings in the machine industry

    Directory of Open Access Journals (Sweden)

    K. Lenik

    2009-06-01

    Full Text Available Purpose: The paper presents the problems of forecasting of durability of waterborne acrylic coatings and epoxy coatings designed to protect devices and machine elements.Design/methodology/approach: The durability forecast has been performed on the basis of analyses of time series with the use of trend function extrapolation. Mechanical properties such as: scratch resistance, impact strength, grindability and luster have also been evaluated. Moreover, besides standardized methods, some complementary methods have been applied in the form of analyses of microscopic images of damage caused by the exposition of coatings to corrosion.Findings: Assuming five-year durability for coatings on devices and machine elements (time between overhauls, one can find that investigated waterborne coatings can be a successful protection of devices and machine elements in the established range and in the dependence on the applied system.Research limitations/implications: The research has shown some substantial influence of coating system width changes on obtained results of scratch resistance and impact strength. It should be beneficial to extend further research with the description of the mechanism that enables to obtain some strict correlation between the investigated properties of coatings and the allowance of their width.Practical implications: The research makes possible to determine the areas of application for coatings obtained from waterborne materials to anticorrosion protection of devices and machine elements. This enables to eliminate gradually traditional solvent coatings (of high VOC content, which are disadvantageous to the environment.Originality/value: The applied sequence of research can form a proposal of the method to evaluate coatings made of some other than investigated waterborne materials predestinated for machine industry.

  20. X-ray diffraction characterization of electrodeposited Ni–Al composite coatings prepared at different current densities

    International Nuclear Information System (INIS)

    Highlights: • Different X-ray diffraction techniques were applied to characterize the Ni–Al composite coatings. • Al2O3 formed on the coating surface after potentiostatic polarization experiments. • The relationship between corrosion and the Al content and the texture were also investigated. - Abstract: Ni–Al composite coatings were prepared at different applied current densities (1–8 A/dm2) from a conventional Watt bath. The influences of current densities on the texture, grain size, microstrain, residual stress of the Ni–Al composite coating were investigated with X-ray diffraction method, which includes texture coefficients (TC) and pole figures, Voigt method, classical sin2 ψ X-ray diffraction method and the Multi-reflection grazing incidence geometry (referred to as MGIXD) method. The morphology, composition, anti-corrosion properties and friction coefficients at 200 °C of the coating were also studied. The results showed that the texture of coating deposited at higher current densities evolved from the (2 0 0) preferred orientation with fiber texture to random orientation with reducing current density. Al particle content increased with reducing current density, grain size decreased with the reducing current density, while the microstrain and the tensile residual stresses increased. The MGIXD result showed stress gradient on the near-surface of the coating. Potentiodynamic polarization results demonstrated that the Ni–Al coating deposited at 2 A/dm2 exhibited the best anti-corrosion which was contributed by the formation of Al2O3 on the surface. The minimum friction coefficient of 0.57 was also observed for coating deposited at 4 A/dm2

  1. Characterization of ceramic sol-gel coatings as an alternative chemical conversion treatment on commercial carbon steel

    Energy Technology Data Exchange (ETDEWEB)

    Dominguez-Crespo, M.A. [Instituto Politecnico Nacional, Grupo de Ingenieria en Procesamiento de Materiales CICATA-IPN, Unidad Altamira, km 14.5, Carretera Tampico-Puerto Industrial Altamira, C.P. 89600 Altamira, Tamps (Mexico)], E-mail: mdominguezc@ipn.mx; Garcia-Murillo, A.; Torres-Huerta, A.M.; Carrillo-Romo, F.J. [Instituto Politecnico Nacional, Grupo de Ingenieria en Procesamiento de Materiales CICATA-IPN, Unidad Altamira, km 14.5, Carretera Tampico-Puerto Industrial Altamira, C.P. 89600 Altamira, Tamps (Mexico); Onofre-Bustamante, E. [Universidad Nacional Autonoma de Mexico, Edificio D Facultad de Quimica, Departamento de Metalurgia, Ciudad Universitaria, C.P. 04510 Mexico D.F. (Mexico); Yanez-Zamora, C. [Alumna del postgrado en Tecnologia Avanzada del CICATA-IPN, Unidad Altamira IPN, km 14.5, Carretera Tampico-Puerto Industrial Altamira, C.P. 89600 Altamira, Tamps (Mexico)

    2009-04-01

    Sol-gel yttria-stabilized zirconia (YSZ) thin films were prepared on commercial carbon steel sheets by dip-coating technique followed by a low temperature heat treatment (473, 573, and 673 K for 1 h) in order to improve both corrosion properties and adhesion. For comparison, zirconia (ZrO{sub 2}) coatings have been also analyzed. Electrochemical techniques, Fourier Transform Infrared (FT-IR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to characterize the anticorrosion behavior of the coatings in a 3.5 wt% NaCl solution. The adhesion with a polyester organic coating was evaluated by the pull-off technique. The typical thickness of the deposited layers ranged from 1 to 1.3 {mu}m depending on process parameters. The obtained results indicated that sol-gel ZrO{sub 2} and YSZ coatings without an organic coating can act as protective barriers against wet corrosion during the first hours, but they fail when the time exposure is longer than 1 day. However, when synthesized films were used as a pre-treatment and an organic coating was added (top-coated), the anticorrosive and adhesion properties were strongly affected by the temperature of the treatment, and an increase in both properties was observed at higher temperatures. The structural and morphological characteristics of the coating provide an explanation of the role of each film in the electrochemical behavior in this aggressive medium. Comparing both systems, YSZ displayed greater protective and adhesion values than exhibited for ZrO{sub 2} which can be correlated with the stabilization of the cubic phase.

  2. Characterization of ceramic sol-gel coatings as an alternative chemical conversion treatment on commercial carbon steel

    International Nuclear Information System (INIS)

    Sol-gel yttria-stabilized zirconia (YSZ) thin films were prepared on commercial carbon steel sheets by dip-coating technique followed by a low temperature heat treatment (473, 573, and 673 K for 1 h) in order to improve both corrosion properties and adhesion. For comparison, zirconia (ZrO2) coatings have been also analyzed. Electrochemical techniques, Fourier Transform Infrared (FT-IR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to characterize the anticorrosion behavior of the coatings in a 3.5 wt% NaCl solution. The adhesion with a polyester organic coating was evaluated by the pull-off technique. The typical thickness of the deposited layers ranged from 1 to 1.3 μm depending on process parameters. The obtained results indicated that sol-gel ZrO2 and YSZ coatings without an organic coating can act as protective barriers against wet corrosion during the first hours, but they fail when the time exposure is longer than 1 day. However, when synthesized films were used as a pre-treatment and an organic coating was added (top-coated), the anticorrosive and adhesion properties were strongly affected by the temperature of the treatment, and an increase in both properties was observed at higher temperatures. The structural and morphological characteristics of the coating provide an explanation of the role of each film in the electrochemical behavior in this aggressive medium. Comparing both systems, YSZ displayed greater protective and adhesion values than exhibited for ZrO2 which can be correlated with the stabilization of the cubic phase

  3. X-ray diffraction characterization of electrodeposited Ni–Al composite coatings prepared at different current densities

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Fei; Jiang, Chuanhai, E-mail: chuanhaijiang1963@163.com; Wu, Xueyan

    2014-08-01

    Highlights: • Different X-ray diffraction techniques were applied to characterize the Ni–Al composite coatings. • Al{sub 2}O{sub 3} formed on the coating surface after potentiostatic polarization experiments. • The relationship between corrosion and the Al content and the texture were also investigated. - Abstract: Ni–Al composite coatings were prepared at different applied current densities (1–8 A/dm{sup 2}) from a conventional Watt bath. The influences of current densities on the texture, grain size, microstrain, residual stress of the Ni–Al composite coating were investigated with X-ray diffraction method, which includes texture coefficients (TC) and pole figures, Voigt method, classical sin{sup 2} ψ X-ray diffraction method and the Multi-reflection grazing incidence geometry (referred to as MGIXD) method. The morphology, composition, anti-corrosion properties and friction coefficients at 200 °C of the coating were also studied. The results showed that the texture of coating deposited at higher current densities evolved from the (2 0 0) preferred orientation with fiber texture to random orientation with reducing current density. Al particle content increased with reducing current density, grain size decreased with the reducing current density, while the microstrain and the tensile residual stresses increased. The MGIXD result showed stress gradient on the near-surface of the coating. Potentiodynamic polarization results demonstrated that the Ni–Al coating deposited at 2 A/dm{sup 2} exhibited the best anti-corrosion which was contributed by the formation of Al{sub 2}O{sub 3} on the surface. The minimum friction coefficient of 0.57 was also observed for coating deposited at 4 A/dm{sup 2}.

  4. Electrochemical and In Vitro Behavior of Nanostructure Sol-Gel Coated 316L Stainless Steel Incorporated with Rosemary Extract

    Science.gov (United States)

    Motalebi, Abolfazl; Nasr-Esfahani, Mojtaba

    2013-06-01

    The corrosion resistance of AISI 316L stainless steel for biomedical applications, was significantly enhanced by means of hybrid organic-inorganic sol-gel thin films deposited by spin-coating. Thin films of less than 100 nm with different hybrid characters were obtained by incorporating rosemary extract as green corrosion inhibitor. The morphology, composition, and adhesion of hybrid sol-gel coatings have been examined by SEM, EDX, and pull-off test, respectively. Addition of high additive concentrations (0.1%) did not disorganize the sol-gel network. Direct pull-off test recorded a mean coating-substrate bonding strength larger than 21.2 MPa for the hybrid sol-gel coating. The effect of rosemary extract, with various added concentrations from 0.012 to 0.1%, on the anticorrosion properties of sol-gel films have been characterized by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization tests in simulated body fluid (SBF) solution and has been compared to the bare metal. Rosemary extract additions (0.05%) have significantly increased the corrosion protection of the sol-gel thin film to higher than 90%. The in vitro bioactivity of prepared films indicates that hydroxyapatite nuclei can form and grow on the surface of the doped sol-gel thin films. The present study shows that due to their excellent anticorrosion properties, bioactivity and bonding strength to substrate, doped sol-gel thin films are practical hybrid films in biomedical applications.

  5. Investigation on a Sol-gel Coating Containing Inhibitors on 2024-T3 Aluminum Alloy

    Institute of Scientific and Technical Information of China (English)

    SHI Hong-wei; LIU Fu-chun; HAN En-hou; SUN Ming-cheng

    2006-01-01

    For a long time, chromate incorporated conversion coatings have been drawn special attention in corrosion protection of aircraft-used aluminum alloys. However,ever-increasing environmental pressures requires that non-chromate conversion coatings be developed because of the detrimental carcinogenic effects of the chromate compounds. In recent years, the sol-gel coatings doped with inhibitors were developed to replace chromate conversion coatings, and showed real promise. A sol-gel coating was prepared and its anti-corrosion behavior was investigated using the potentiodynamic scanning (PDS) and the electrochemical impedance spectroscopy (EIS). It is found that the sol-gel coating obtained by the hydrolysis and condensation of 3-glycidoxypropyltrimethoxysilane (GPTMS) and tetramethoxysilane (TMOS) is prone to form defects if cured at the room temperature, whereas if cured at a higher temperature (100 ℃), these flaws can be avoided. Furthermore, it can be seen that addition of anti-foam agents and surfactants will reduce the faults if cured at the room temperature. Effects of the corrosion inhibitors, CeCl3 and mercaptobenzothiazole (MBT), in the sol-gel coatings on 2024-T3 aluminum alloy were also investigated. Results show that the corrosion resistance of the sol-gel coatings containing CeCl3 proves to be better than that of the pure and MBT added sol-gel coatings by the electrochemical methods.

  6. An assessment of solid-wire film coatings for MAG welding

    International Nuclear Information System (INIS)

    Solid electrode-wires, intended for MAG welding, are made of common and low-alloy constructional steels and are usually coated with a thin copper film whose role is to ensure good electrical contact in the contact tube (the current terminal), a low level of resistance to feed in the spiral of the MAG welding clamp, and a temporary anticorrosion protection. The present paper contains results of the investigations into the properties of film coatings on G3Sil-EN 440 solid wires. The assessment of the wire properties was based on the criteria established in the course of the experimentation. This was necessary because the available standards for the welding wires do not uniquely specify requirements regarding factors such as, for instance, film thickness, its uniformity and surface roughness which influence the quality of the coating

  7. Polishing characteristics of optical glass using PMMA-coated carbonyl-iron-based magnetorheological fluid

    Science.gov (United States)

    Lee, J. W.; Hong, K. P.; Cho, M. W.; Kwon, S. H.; Choi, H. J.

    2015-06-01

    Soft magnetic carbonyl iron (CI) particles for magnetorheological (MR) polishing encounter corrosion problems as a result of their oxidation, leading to unpredictable polishing results. To overcome this issue, CI particles have been coated with either polymer or inorganic materials for improved MR polishing. In this study, CI particles were coated with poly(methyl methacrylate) to achieve improved MR polishing and anti-corrosion protection. In addition to an analysis of their rheological properties, a series of MR polishing experiments were performed to investigate the material removal rate and surface roughness for BK7 optical glass by changing experimental parameters, such as the wheel rotating speed and magnetic field intensity. A very fine surface roughness (Ra = 0.86 nm for PMMA coated CI/Ra = 0.92 nm for pristine CI) was obtained at a wheel speed of 1256 mm s-1 and a magnetic field intensity of 15.92 kA m-1.

  8. Electropolymerization of poly (aniline-co-o-anisidine) on copper and its anticorrosion properties

    International Nuclear Information System (INIS)

    Poly(aniline-co-o-anisidine) of copolymer coatings was synthesized on the copper surface (Cu) with two different amounts of p-toluenesulfonic acid (p-TSA) added to the aqueous sodium oxalate (NaOX) solution. The copper substrates in NaOX solutions containing p-TSA acid had a fairly reliable passive surface mainly due to the formation of copper (II) oxalate layer. The addition of p-TSA acid to the working electrolyte contributed to both the amount of copolymer deposition (growth) and that of copolymer coated per unit time of electropolymerization (growth rate). The growth of copolymer coating on Cu electrode was characterized by scanning electron microscopy. The corrosion performances of copolymer coatings were investigated in 3.5% NaCl solution with anodic polarization curves and electrochemical impedance spectroscopy. The results showed that p-TSA acid led to the diminishing of the permeability of the copolymer films. The copolymer coatings exhibited an effective barrier property on copper electrode and a remarkable anodic protection to substrate for longer exposure time

  9. Fabrication of TiO2-strontium loaded CaSiO3/biopolymer coatings with enhanced biocompatibility and corrosion resistance by controlled release of minerals for improved orthopedic applications.

    Science.gov (United States)

    Raj, V; Raj, R Mohan; Sasireka, A; Priya, P

    2016-07-01

    Titanium dioxide (TiO2) arrays were fabricated on Ti alloy by anodization method. Synthesis of CaSiO3 (CS) and various concentrations (1X-5X) of Sr(2+) substitutions in CS coatings on TiO2 substrate was achieved through an electrophoretic deposition technique. Fast release of mineral ions from implant surface produce over dosage effect and it is a potential hazardous factor for osteoblasts. So, in order to prevent the fast release of minerals, biopolymer coating was applied above the composite coatings. The coatings were characterized by FTIR, XRD, FE-SEM and EDX techniques. The mechanical, anticorrosion, antimicrobial properties and biocompatibility of the coatings were evaluated. Studies on the mechanical properties indicate that the addition of Sr(2+) and biopolymer increase the hardness strength of the coatings. The metal ion release from the coatings was studied by ICP-AES. The electrochemical properties of the coatings were studied in Ringer's solution, in which CS-3X/Chi-PVP coating on TiO2 exhibits good anticorrosion property and high resistivity against Escherichia coli and Staphylococcus aureus compared to CS-3X coating on TiO2. In vitro cell experiments indicate that osteoblasts show good adhesion and high growth rates for CS-3X/Chi-PVP coated TiO2 substrate, indicating that the surface cytocompatibility of CS-3X/Chi-PVP coated TiO2 substrate is significantly improved by the controlled release of mineral ions. In conclusion, the surface modification of TiO2/CS-3X/Chi-PVP coated titanium is a potential candidate for implant coating. PMID:27018944

  10. Bioinspired Composite Coating with Extreme Underwater Superoleophobicity and Good Stability for Wax Prevention in the Petroleum Industry.

    Science.gov (United States)

    Liang, Weitao; Zhu, Liqun; Li, Weiping; Yang, Xin; Xu, Chang; Liu, Huicong

    2015-10-13

    Wax deposition is a detrimental problem that happens during crude oil production and transportation, which greatly reduces transport efficiency and causes huge economic losses. To avoid wax deposition, a bioinspired composite coating with excellent wax prevention and anticorrosion properties is developed in this study. The prepared coating is composed of three films, including an electrodeposited Zn film for improving corrosion resistance, a phosphating film for constructing fish-scale morphology, and a silicon dioxide film modified by a simple spin-coating method for endowing the surface with superhydrophilicity. Good wax prevention performance has been investigated in a wax deposition test. The surface morphology, composition, wetting behaviors, and stability are systematically studied, and a wax prevention mechanism is proposed, which can be calculated from water film theory. This composite coating strategy which shows excellent properties in both wax prevention and stability is expected to be widely applied in the petroleum industry. PMID:26375275

  11. Electrophoretic deposition of ZnO/alginate and ZnO-bioactive glass/alginate composite coatings for antimicrobial applications

    International Nuclear Information System (INIS)

    Two organic/inorganic composite coatings based on alginate, as organic matrix, and zinc oxide nanoparticles (n-ZnO) with and without bioactive glass (BG), as inorganic components, intended for biomedical applications, were developed by electrophoretic deposition (EPD). Different n-ZnO (1–10 g/L) and BG (1–1.5 g/L) contents were studied for a fixed alginate concentration (2 g/L). The presence of n-ZnO was confirmed to impart antibacterial properties to the coatings against gram-negative bacteria Escherichia coli, while the BG induced the formation of hydroxyapatite on coating surfaces thereby imparting bioactivity, making the coating suitable for bone replacement applications. Coating composition was analyzed by thermogravimetric analysis (TG), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS) analyses. Scanning electron microscopy (SEM) was employed to study both the surface and the cross section morphology of the coatings. Polarization curves of the coated substrates made in cell culture media at 37 °C confirmed the corrosion protection function of the novel organic/inorganic composite coatings. - Highlights: • Organic–inorganic nanocomposite coatings fabricated by electrophoretic deposition • nZnO and bioactive glass containing alginate coatings exhibit antibacterial effect. • Bioactive character and anticorrosion function of coatings demonstrated

  12. Electrophoretic deposition of ZnO/alginate and ZnO-bioactive glass/alginate composite coatings for antimicrobial applications

    Energy Technology Data Exchange (ETDEWEB)

    Cordero-Arias, L.; Cabanas-Polo, S.; Goudouri, O.M. [Institute of Biomaterials, Department of Materials Science and Engineering, University of Erlangen-Nuremberg, Cauerstrasse 6, D-91058 Erlangen (Germany); Misra, S.K. [Materials Science and Engineering, Indian Institute of Technology Gandhinagar, Ahmedabad 382424 (India); Gilabert, J. [Institute of Ceramics Materials (ITC), University Jaume I, Avenida Vicent SosBaynat, 12006 Castellon (Spain); Valsami-Jones, E. [School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Sanchez, E. [Institute of Ceramics Materials (ITC), University Jaume I, Avenida Vicent SosBaynat, 12006 Castellon (Spain); Virtanen, S. [Institute for Surface Science and Corrosion (LKO, WW4), Department of Materials Science and Engineering, University of Erlangen-Nuremberg, Martensstrasse 7, D-91058 Erlangen (Germany); Boccaccini, A.R., E-mail: aldo.boccaccini@ww.uni-erlangen.de [Institute of Biomaterials, Department of Materials Science and Engineering, University of Erlangen-Nuremberg, Cauerstrasse 6, D-91058 Erlangen (Germany)

    2015-10-01

    Two organic/inorganic composite coatings based on alginate, as organic matrix, and zinc oxide nanoparticles (n-ZnO) with and without bioactive glass (BG), as inorganic components, intended for biomedical applications, were developed by electrophoretic deposition (EPD). Different n-ZnO (1–10 g/L) and BG (1–1.5 g/L) contents were studied for a fixed alginate concentration (2 g/L). The presence of n-ZnO was confirmed to impart antibacterial properties to the coatings against gram-negative bacteria Escherichia coli, while the BG induced the formation of hydroxyapatite on coating surfaces thereby imparting bioactivity, making the coating suitable for bone replacement applications. Coating composition was analyzed by thermogravimetric analysis (TG), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS) analyses. Scanning electron microscopy (SEM) was employed to study both the surface and the cross section morphology of the coatings. Polarization curves of the coated substrates made in cell culture media at 37 °C confirmed the corrosion protection function of the novel organic/inorganic composite coatings. - Highlights: • Organic–inorganic nanocomposite coatings fabricated by electrophoretic deposition • nZnO and bioactive glass containing alginate coatings exhibit antibacterial effect. • Bioactive character and anticorrosion function of coatings demonstrated.

  13. Application of the electrochemical noise method to evaluate the effectiveness of modification of zinc phosphate anticorrosion pigment

    International Nuclear Information System (INIS)

    A variety of approaches have been proposed to achieve an enhancement regarding inhibitive performance of zinc phosphate (ZP) anticorrosion pigment. This work attempts to study behavior of zinc aluminum polyphosphate (ZAPP) representing modified zinc phosphate pigment through electrochemical techniques along with surface analysis. Analysis of the data obtained from electrochemical noise method revealed superiority of ZAPP compared to ZP. The amplitude of the current noise fluctuation and trend of noise resistance variation as well as shot noise theory suggested precipitation of a protective layer in the presence of ZAPP, restricting access of the aggressive species to the steel surface. X-ray photoelectron spectroscopy (XPS) was employed to analyze the sample surface exposed to 3.5% NaCl solution containing modified pigment extract.

  14. Characteristics and anticorrosion performance of Fe-doped TiO2 films by liquid phase deposition method

    International Nuclear Information System (INIS)

    Highlights: • Fe-doped TiO2 films were prepared by liquid phase deposition method. • Higher photoelectrochemical response was observed for the Fe-doped TiO2 film. • The sustained anticorrosion behavior for SUS304 stainless steel was observed. - Abstract: Fe-doped TiO2 thin films were fabricated by liquid phase deposition (LPD) method, using Fe(III) nitrate as both Fe element source and fluoride scavenger instead of commonly-used boric acid (H3BO3). Scanning electron microscopy (SEM), X-ray diffraction (XRD), and UV–vis spectrum were employed to examine the effects of Fe element on morphology, structure and optical characteristics of TiO2 films. The as-prepared films were served as photoanode applied to photogenerated cathodic protection of SUS304 stainless steel (304SS). It was observed that the photoelectrochemical properties of the as-prepared films were enhanced with the addition of Fe element compared to the undoped TiO2 film. The highest photoactivity was achieved for Ti13Fe (Fe/Ti = 3 molar ratio) film prepared in precursor bath containing 0.02 M TiF4 + 0.06 M Fe(NO3)3 under white-light illumination. The effective anticorrosion behaviors can be attributed to the Fe element incorporation which decreases the probability of photogenerated charge-carrier recombination and extends the light response range of Fe-doped TiO2 films appeared to visible-light region

  15. Effect of Synthesizing Temperature on Microstructure and Electrochemical Property of the Hydrothermal Conversion Coating on Mg-2Zn-0.5Mn-Ca-Ce Alloy

    Directory of Open Access Journals (Sweden)

    Guanghui Guo

    2016-02-01

    Full Text Available Mg(OH2 conversion coatings were formed on an Mg-2Zn-0.5Mn-Ca-Ce alloy via hydrothermal method at three different synthesizing temperatures (160, 170 and 180 °C. The effect of synthesizing temperature on microstructure and electrochemical property of the coatings were systematically studied. With increasing synthesizing temperature, the coating became thicker due to the faster reaction and deposition of Mg(OH2 on the α-Mg phase and secondary phases of the substrate Mg alloy. Internal micro-cracks were also generated in the higher-temperature synthesized coatings due to the increased shrinking stress, but the cross-cutting micro-cracks were suppressed. Benefiting from the improved barrier effect against penetration of corrosive medium, the higher-temperature synthesized thicker coating presented significantly enhanced electrochemical property and anti-corrosion efficiency in Hanks’ solution.

  16. The study of steel protection effect by application of molten active microalloyed aluminum and by covering that composition by organic coating

    Directory of Open Access Journals (Sweden)

    Purenović Milovan M.

    2002-01-01

    Full Text Available In this paper, the steel active-passive anticorrosive protection was done. Steel plates samples with dimensions 40 ×100 ×2 millimeters were used. Samples surfaces preparation was done by degreasing, then by sandblasting by pneumatic pistol. The metallising by molten metal was done by hand pistol which worked with metal vein "Protector" (ø 3,18 millimeters of electrochemical active anode material on the basis of microalloyed aluminum. The mentioned application was done twice and obtained layer thickness was 150-200 micrometers. After this operation, organic coating "Vinilpom", the product of Coatings Industry "Pomoravlje", was applied. Coating quality was followed by measuring of coating thickness, of dried film hardness, level of connecting with a base and of gloss. Whole composition steel - "Protector", organic coating electrochemical study was done by measuring of galvanic team electrochemical potential change in 20% NaCl solution, during the time.

  17. Investigation of the Corrosion Behavior of Poly(Aniline-co-o-Anisidine)/ZnO Nanocomposite Coating on Low-Carbon Steel

    Science.gov (United States)

    Mobin, M.; Alam, R.; Aslam, J.

    2016-05-01

    A copolymer of aniline (AN) and o-anisidine (OA), Poly(AN-co-OA) and its nanocomposite with ZnO nanoparticles, Poly(AN-co-OA)/ZnO were synthesized by chemical oxidative polymerization using ammonium persulfate as an oxidant in hydrochloric acid medium. The synthesized compounds were characterized using FTIR, XRD, SEM-EDS, TEM, and electrical conductivity techniques. The copolymer and nanocomposite were separately dissolved in N-methyl-2-pyrrolidone and were casted on low-carbon steel specimens using 10% epoxy resin as a binder. The anticorrosive properties of the coatings were studied in different corrosive environments such as 0.1 M HCl, 5% NaCl solution, and distilled water at a temperature of 30 °C by conducting corrosion tests which include immersion test, open circuit potential measurements, potentiodynamic polarization measurements, and atmospheric exposure test. The surface morphology of the coatings prior to and after one-month immersion in corrosive solution was evaluated using SEM. It was observed that the nanocomposite coating exhibited higher corrosion resistance and provided better barrier properties in comparison with copolymer coating. The presence of ZnO nanoparticles improved the anticorrosion properties of copolymer coating in all corrosive media subjected to investigation.

  18. Investigation of the Corrosion Behavior of Poly(Aniline-co-o-Anisidine)/ZnO Nanocomposite Coating on Low-Carbon Steel

    Science.gov (United States)

    Mobin, M.; Alam, R.; Aslam, J.

    2016-07-01

    A copolymer of aniline (AN) and o-anisidine (OA), Poly(AN-co-OA) and its nanocomposite with ZnO nanoparticles, Poly(AN-co-OA)/ZnO were synthesized by chemical oxidative polymerization using ammonium persulfate as an oxidant in hydrochloric acid medium. The synthesized compounds were characterized using FTIR, XRD, SEM-EDS, TEM, and electrical conductivity techniques. The copolymer and nanocomposite were separately dissolved in N-methyl-2-pyrrolidone and were casted on low-carbon steel specimens using 10% epoxy resin as a binder. The anticorrosive properties of the coatings were studied in different corrosive environments such as 0.1 M HCl, 5% NaCl solution, and distilled water at a temperature of 30 °C by conducting corrosion tests which include immersion test, open circuit potential measurements, potentiodynamic polarization measurements, and atmospheric exposure test. The surface morphology of the coatings prior to and after one-month immersion in corrosive solution was evaluated using SEM. It was observed that the nanocomposite coating exhibited higher corrosion resistance and provided better barrier properties in comparison with copolymer coating. The presence of ZnO nanoparticles improved the anticorrosion properties of copolymer coating in all corrosive media subjected to investigation.

  19. Anticorrosion properties of inorganic pigments surface-modified with a polyaniline phosphate layer

    Czech Academy of Sciences Publication Activity Database

    Kalendová, A.; Veselý, D.; Stejskal, Jaroslav; Trchová, Miroslava

    2008-01-01

    Roč. 63, č. 2 (2008), s. 209-221. ISSN 0300-9440 Institutional research plan: CEZ:AV0Z40500505 Keywords : polyaniline * conducting polymer * coating Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.375, year: 2008

  20. Chromate-free Hybrid Coating for Corrosion Protection of Electrogalvanized Steel Sheets

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Duhwan; Kwon, Moonjae; Kim, Jongsang [POSCO Technical Research Laboratories, Pohang (Korea, Republic of)

    2012-01-15

    Both electrogalvanized and hot-dip galvanized steel sheets have been finally produced via organic-inorganic surface coating process on the zinc surface to enhance corrosion resistance and afford additional functional properties. Recently, POSCO has been developed a variety of chromate-free coated steels that are widely used in household, construction and automotive applications. New organic-inorganic hybrid coating solutions as chromate alternatives are comprised of surface modified silicate with silane coupling agent and inorganic corrosion inhibitors as an aqueous formulation. In this paper we have prepared new type of hybrid coatings and evaluated quality performances such as corrosion resistance, spot weldability, thermal tolerance, and paint adhesion property etc. The electrogalvanized steels with these coating solutions exhibit good anti-corrosion property compared to those of chromate coated steels. Detailed components composition of coating solutions and experimental results suggest that strong binding between organic-inorganic hybrid coating layer and zinc surface plays a key role in the advanced quality performances.

  1. Functional Coatings or Films for Hard-Tissue Applications

    Directory of Open Access Journals (Sweden)

    Guocheng Wang

    2010-07-01

    Full Text Available Metallic biomaterials like stainless steel, Co-based alloy, Ti and its alloys are widely used as artificial hip joints, bone plates and dental implants due to their excellent mechanical properties and endurance. However, there are some surface-originated problems associated with the metallic implants: corrosion and wear in biological environments resulting in ions release and formation of wear debris; poor implant fixation resulting from lack of osteoconductivity and osteoinductivity; implant-associated infections due to the bacterial adhesion and colonization at the implantation site. For overcoming these surface-originated problems, a variety of surface modification techniques have been used on metallic implants, including chemical treatments, physical methods and biological methods. This review surveys coatings that serve to provide properties of anti-corrosion and anti-wear, biocompatibility and bioactivity, and antibacterial activity.

  2. The n-MAO/EPD bio-ceramic composite coating fabricated on ZK60 magnesium alloy using combined micro-arc oxidation with electrophoretic deposition

    International Nuclear Information System (INIS)

    Highlights: • Adding CeO2/ZrO2 nano-particles to modify the properties of n-MAO coating. • A bio-ceramic n-MAO/EPD composite coating was prepared by two-step methods. • The n-MAO/EPD composite coating with HA has a favorable anti-corrosion effect. - Abstract: A bio-ceramic composite coating was fabricated on ZK60 magnesium (Mg) alloy using combined micro-arc oxidation (MAO) with electrophoretic deposition (EPD) technique. The MAO coating as the basal layer was produced in alkaline electrolyte with (n-MAO coating) and without (MAO coating) the addition of CeO2 and ZrO2 nano-particles, respectively. A hydroxyapatite (HA) coating as the covering layer was deposited on the n-MAO coating to improve the biological properties of the coating (n-MAO/EPD composite coating). The morphology and phase composition of three treated coatings were investigated by scanning electron microscope (SEM) and X-ray diffraction (XRD). The corrosion resistance of these coatings was evaluated with potentiodynamic polarization tests and immersion tests in simulated body fluid (SBF) at 36.5 ± 0.5 °C. The XRD spectra showed that the CeO2 and ZrO2 peaks can be collected in the n-MAO coating, and HA particles exists in the n-MAO/EPD composite coating. The results of corrosion tests indicated that the n-MAO/EPD composite coating owned increased bioactivity and long-term protective ability compared with the MAO coating and the n-MAO coating. Thus Mg alloy coated with the n-MAO/EPD composite coating should be more suited as biodegradable bone implants

  3. The n-MAO/EPD bio-ceramic composite coating fabricated on ZK60 magnesium alloy using combined micro-arc oxidation with electrophoretic deposition

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Ying, E-mail: yxiong@zjut.edu.cn [College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310032 (China); Lu, Chao [College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310032 (China); Wang, Chao; Song, Renguo [School of Materials Science and Engineering, Changzhou University, Changzhou 213164 (China); Jiangsu Key Laboratory of Materials Surface Science and Technology, Changzhou University, Changzhou 213164 (China)

    2014-12-15

    Highlights: • Adding CeO{sub 2}/ZrO{sub 2} nano-particles to modify the properties of n-MAO coating. • A bio-ceramic n-MAO/EPD composite coating was prepared by two-step methods. • The n-MAO/EPD composite coating with HA has a favorable anti-corrosion effect. - Abstract: A bio-ceramic composite coating was fabricated on ZK60 magnesium (Mg) alloy using combined micro-arc oxidation (MAO) with electrophoretic deposition (EPD) technique. The MAO coating as the basal layer was produced in alkaline electrolyte with (n-MAO coating) and without (MAO coating) the addition of CeO{sub 2} and ZrO{sub 2} nano-particles, respectively. A hydroxyapatite (HA) coating as the covering layer was deposited on the n-MAO coating to improve the biological properties of the coating (n-MAO/EPD composite coating). The morphology and phase composition of three treated coatings were investigated by scanning electron microscope (SEM) and X-ray diffraction (XRD). The corrosion resistance of these coatings was evaluated with potentiodynamic polarization tests and immersion tests in simulated body fluid (SBF) at 36.5 ± 0.5 °C. The XRD spectra showed that the CeO{sub 2} and ZrO{sub 2} peaks can be collected in the n-MAO coating, and HA particles exists in the n-MAO/EPD composite coating. The results of corrosion tests indicated that the n-MAO/EPD composite coating owned increased bioactivity and long-term protective ability compared with the MAO coating and the n-MAO coating. Thus Mg alloy coated with the n-MAO/EPD composite coating should be more suited as biodegradable bone implants.

  4. A preserving procedure for the anti-corrosive shielding in the H2O-H2S isotopic exchange installations

    International Nuclear Information System (INIS)

    The anti-corrosive protection of the H2O-H2S isotopic exchange installations consisting of an adherent deposition of iron sulfides, particularly pyrite and pyrotite, undergo at the contact with atmospheric air degrading processes which impair their protective role against the operation environment. Consequently, for long period of interruption, preserving measures should be provided. The procedure achieved and applied in the pilot installation of ICIS - Rm.Valcea consists in pressurization at 0.5 - 2 bar with nitrogen or hydrogen sulfide of the equipment, while the oxygen containing gases should not exceed a 0.1% volume. The experimental testing have determined that after an 1 year period the anti-corrosive protection do not undergo modifications in what concerns the morpho-structural characteristics of the passivating layers. This procedure is recommended for conserving the GS ROMAG installations over long periods

  5. An investigation of the biochemical properties of tetrazines as potential coating additives

    International Nuclear Information System (INIS)

    1,2,4,5-Tetrazine and its 3,6-disubstituted derivatives are currently used for a range of industrial and medical applications as they exhibit particular coordination chemistries, characterised by electron and charge transfer phenomena. The aim of the present work is to synthesise two tetrazine derivatives, namely 3,6-dihydrazino-1,2,4,5-tetrazine (DHDTZ) and 1,2,4,5-tetrazine dicarboxylic acid (DCTZ), and determine their antibacterial, antioxidant and anticorrosion characteristics as additives in a sol–gel coating on SS316L steel. The structure of the tetrazines was confirmed by NMR and FTIR while the surface morphology of bacterial cells in their presence was observed by AFM. Their ability to inhibit corrosion on 316L stainless steel was electrochemically determined using a potentiodynamic scanning (PDS) technique. The corrosion inhibition results showed that the acidic DCTZ provided the best corrosion protection. The concentration-dependent antioxidant capacity of the tetrazines was confirmed by both DPPH radical scavenging activity and FRAP assays, showing higher activity for DHDTZ than DCTZ. Furthermore, a DHDTZ doped sol–gel solution was prepared and curing parameter (temperature and time) was optimised for coating on microtitre wells and stainless steel panel. The antibacterial activity of the coated surfaces against Pseudomonas aeruginosa ATCC 27853 and the biofilm forming bacteria Staphylococcus epidermidis CSF 41498 was determined. DHDTZ showed significantly higher antibacterial activities with MIC as low as 31 ppm compared to 250 ppm for DCTZ. Highlights: ► Tetrazine derivatives showed strong antibacterial activity against bacterial pathogens. ► Electrochemical studies confirmed the anticorrosion property of the compounds. ► Significant antioxidant activity was exhibited by the compounds. ► Tetrazine doped sol–gel coating inhibited bacterial growth on 316L stainless steel. ► Tetrazine derivatives can be used as a potential hygiene coating

  6. An investigation of the biochemical properties of tetrazines as potential coating additives

    Energy Technology Data Exchange (ETDEWEB)

    Jaiswal, Swarna [School of Biological Sciences, Dublin Institute of Technology, Kevin Street, Dublin 8 (Ireland); Centre for Research in Engineering Surface Technology (CREST), FOCAS Institute, Dublin Institute of Technology, Dublin 8 (Ireland); Varma, P.C. Rajath [Centre for Research in Engineering Surface Technology (CREST), FOCAS Institute, Dublin Institute of Technology, Dublin 8 (Ireland); O' Neill, Luke [FOCAS Institute, Dublin Institute of Technology, Dublin 8 (Ireland); Duffy, Brendan, E-mail: brendan.duffy@dit.ie [Centre for Research in Engineering Surface Technology (CREST), FOCAS Institute, Dublin Institute of Technology, Dublin 8 (Ireland); McHale, Patrick [School of Biological Sciences, Dublin Institute of Technology, Kevin Street, Dublin 8 (Ireland)

    2013-05-01

    1,2,4,5-Tetrazine and its 3,6-disubstituted derivatives are currently used for a range of industrial and medical applications as they exhibit particular coordination chemistries, characterised by electron and charge transfer phenomena. The aim of the present work is to synthesise two tetrazine derivatives, namely 3,6-dihydrazino-1,2,4,5-tetrazine (DHDTZ) and 1,2,4,5-tetrazine dicarboxylic acid (DCTZ), and determine their antibacterial, antioxidant and anticorrosion characteristics as additives in a sol–gel coating on SS316L steel. The structure of the tetrazines was confirmed by NMR and FTIR while the surface morphology of bacterial cells in their presence was observed by AFM. Their ability to inhibit corrosion on 316L stainless steel was electrochemically determined using a potentiodynamic scanning (PDS) technique. The corrosion inhibition results showed that the acidic DCTZ provided the best corrosion protection. The concentration-dependent antioxidant capacity of the tetrazines was confirmed by both DPPH radical scavenging activity and FRAP assays, showing higher activity for DHDTZ than DCTZ. Furthermore, a DHDTZ doped sol–gel solution was prepared and curing parameter (temperature and time) was optimised for coating on microtitre wells and stainless steel panel. The antibacterial activity of the coated surfaces against Pseudomonas aeruginosa ATCC 27853 and the biofilm forming bacteria Staphylococcus epidermidis CSF 41498 was determined. DHDTZ showed significantly higher antibacterial activities with MIC as low as 31 ppm compared to 250 ppm for DCTZ. Highlights: ► Tetrazine derivatives showed strong antibacterial activity against bacterial pathogens. ► Electrochemical studies confirmed the anticorrosion property of the compounds. ► Significant antioxidant activity was exhibited by the compounds. ► Tetrazine doped sol–gel coating inhibited bacterial growth on 316L stainless steel. ► Tetrazine derivatives can be used as a potential hygiene coating

  7. A novel method to prepare superhydrophobic, UV resistance and anti-corrosion steel surface

    KAUST Repository

    Isimjan, Tayirjan T.

    2012-11-01

    Both TiO 2 and SiO 2 coated steel surfaces containing micro- and nanoscale binary structures with different surface roughness were successfully fabricated by means of a facile layer by layer deposition process followed by heat treatment. The resulting surfaces were modified by the low free energy chemical PTES (1H,1H,2H,2H-Perfluorodecyltriethoxysilane). The experimental results of wettability exhibit that such modified surfaces have a strong repulsive force to water droplets, their static contact angles exceed 165°, receding angle>160°, advanced angles>170° and slide angle<1°. The resulting surfaces not only exhibit superhydrophobic properties but also show strong UV resistance (after coating SiO 2 on top of TiO 2) and strong stability to various solvents including 0.01% HCl solution. © 2012 Elsevier B.V.

  8. Influence of a microcomposite and a nanocomposite on the properties of an epoxy-based powder coating

    Energy Technology Data Exchange (ETDEWEB)

    Piazza, Diego [Polymers Laboratory, Caxias do Sul University - Exact Science and Technology Center, Francisco Getulio Vargas Street, 1130, Petropolis, CEP 95070-560 Caxias do Sul, RS (Brazil); Lorandi, Natalia P. [Corrosion and Surface Protection Laboratory, Caxias do Sul University - Exact Science and Technology Center, Francisco Getulio Vargas Street, 1130, Petropolis, CEP 95070-560 Caxias do Sul, RS (Brazil); Pasqual, Charles I. [Polymers Laboratory, Caxias do Sul University - Exact Science and Technology Center, Francisco Getulio Vargas Street, 1130, Petropolis, CEP 95070-560 Caxias do Sul, RS (Brazil); Scienza, Lisete C. [Corrosion and Surface Protection Laboratory, Caxias do Sul University - Exact Science and Technology Center, Francisco Getulio Vargas Street, 1130, Petropolis, CEP 95070-560 Caxias do Sul, RS (Brazil); Zattera, Ademir J., E-mail: ajzattera@terra.com.br [Polymers Laboratory, Caxias do Sul University - Exact Science and Technology Center, Francisco Getulio Vargas Street, 1130, Petropolis, CEP 95070-560 Caxias do Sul, RS (Brazil)

    2011-08-25

    Highlights: {yields} New materials for using as protective coatings for metal surfaces. {yields} Development of nanostructured powder paints. {yields} Characterization of the new material in the powder and coating form. {yields} Development of a new material for use in the automotive industry, industrial production of appliances, furniture industry. {yields} Development of new material using the process of mixing using a twin-screw extruder, followed by sintering process on a metal plate. - Abstract: The incorporation of nanoclays into coatings has been considered to be commercially favorable due to the improvements obtained in the barrier, thermal, and anticorrosion properties, among others, leading to the development of a new segment in the area of clean technologies: the application of nanocomposites to powder coatings. In this study, in order to compare the performance of a powder coating with the addition of a conventional load (barium sulfate) and a montmorillonite clay (MMT), two mixtures of commercial epoxy-based powder coating were prepared in the melt state, with the addition of 2 and 4% (w/w) of MMT, or 2 and 4% (w/w) of barium sulfate (BaSO{sub 4}). The thermal properties were investigated through thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to evaluate the load dispersion and the morphology of the systems formed. The physical and anticorrosion properties of the coatings were also investigated. The interaction of the MMT with the polymeric matrix, associated to the aspect ratio, resulted in better barrier properties, thermal stability, and adhesion to the metal substrate.

  9. Influence of a microcomposite and a nanocomposite on the properties of an epoxy-based powder coating

    International Nuclear Information System (INIS)

    Highlights: → New materials for using as protective coatings for metal surfaces. → Development of nanostructured powder paints. → Characterization of the new material in the powder and coating form. → Development of a new material for use in the automotive industry, industrial production of appliances, furniture industry. → Development of new material using the process of mixing using a twin-screw extruder, followed by sintering process on a metal plate. - Abstract: The incorporation of nanoclays into coatings has been considered to be commercially favorable due to the improvements obtained in the barrier, thermal, and anticorrosion properties, among others, leading to the development of a new segment in the area of clean technologies: the application of nanocomposites to powder coatings. In this study, in order to compare the performance of a powder coating with the addition of a conventional load (barium sulfate) and a montmorillonite clay (MMT), two mixtures of commercial epoxy-based powder coating were prepared in the melt state, with the addition of 2 and 4% (w/w) of MMT, or 2 and 4% (w/w) of barium sulfate (BaSO4). The thermal properties were investigated through thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to evaluate the load dispersion and the morphology of the systems formed. The physical and anticorrosion properties of the coatings were also investigated. The interaction of the MMT with the polymeric matrix, associated to the aspect ratio, resulted in better barrier properties, thermal stability, and adhesion to the metal substrate.

  10. One-step electrodeposition of self-assembled colloidal particles: a novel strategy for biomedical coating.

    Science.gov (United States)

    Sun, Jiadi; Liu, Xiaoya; Meng, Long; Wei, Wei; Zheng, Yufeng

    2014-09-23

    A novel biomedical coating was prepared from self-assembled colloidal particles through direct electrodeposition. The particles, which are photo-cross-linkable and nanoscaled with a high specific surface area, were obtained via self-assembly of amphiphilic poly(γ-glutamic acid)-g-7-amino-4-methylcoumarin (γ-PGA-g-AMC). The size, morphology, and surface charge of the resulting colloidal particles and their dependence on pH, initial concentrations, and UV irradiation were successfully studied. A nanostructured coating was formed in situ on the surface of magnesium alloys by electrodeposition of colloidal particles. The composition, morphology, and phase of the coating were monitored using Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, scanning electron microscopy, and X-ray diffraction. The corrosion test showed that the formation of the nanostructured coating on magnesium alloys effectively improved their initial anticorrosion properties. More importantly, the corrosion resistance was further enhanced by chemical photo-cross-linking. In addition, the low cytotoxicity of the coated samples was confirmed by MTT assay against NIH-3T3 normal cells. The contribution of our work lies in the creation of a novel strategy to fabricate a biomedical coating in view of the versatility of self-assembled colloidal particles and the controllability of the electrodeposition process. It is believed that our work provides new ideas and reliable data to design novel functional biomedical coatings. PMID:25162374

  11. HYDROTHERMALLY SELF-ADVANCING HYBRID COATINGS FOR MITIGATING CORROSION OF CARBON STEEL.

    Energy Technology Data Exchange (ETDEWEB)

    SUGAMA, T.

    2006-11-22

    Hydrothermally self-advancing hybrid coatings were prepared by blending two starting materials, water-borne styrene acrylic latex (SAL) as the matrix and calcium aluminate cement (CAC) as the hydraulic filler, and then their usefulness was evaluated as the room temperature curable anti-corrosion coatings for carbon steel in CO{sub 2}-laden geothermal environments at 250 C. The following two major factors supported the self-improving mechanisms of the coating during its exposure in an autoclave: First was the formation of a high temperature stable polymer structure of Ca-complexed carboxylate groups containing SAL (Ca-CCG-SAL) due to hydrothermal reactions between SAL and CAC; second was the growth with continuing exposure time of crystalline calcite and boehmite phases coexisting with Ca-CCG-SAL. These two factors promoted the conversion of the porous microstructure in the non-autoclaved coating into a densified one after 7 days exposure. The densified microstructure not only considerably reduced the conductivity of corrosive ionic electrolytes through the coatings' layers, but also contributed to the excellent adherence of the coating to underlying steel' s surface that, in turn, retarded the cathodic oxygen reduction reaction at the corrosion site of steel. Such characteristics including the minimum uptake of corrosive electrolytes by the coating and the retardation of the cathodic corrosion reaction played an important role in inhibiting the corrosion of carbon steel in geothermal environments.

  12. Influence of the cooling method on the structure of 55AlZn coatings

    International Nuclear Information System (INIS)

    In metallization processes, metals or metal alloys are used which have a low melting point and good anticorrosion properties. Moreover, they must form durable intermetallic compounds with iron or its alloys. The most common hot-dip metallization technology involves galvanizing, however, molten multi-component metal alloys are used as well. An addition of aluminium to the zinc bath causes an increase in corrosion resistance of the obtained coatings. The article presents results of tests of obtaining coatings by the batch hot-dip method in an 55AlZn bath. Kinetics of the coating growth in the tested alloys were determined in the changeable conditions of bath temperature, dip time and type of cooling. The structure of coatings and their phase composition were revealed. As a result of the tests performed, it has been found that an increase in total thickness of the coatings as a function of the dipping time at a constant temperature is almost of a parabolic nature, whereas an increase in the transient layer is of a linear nature. The structure was identified by the XRD analysis and the morphology of the coatings was tested by means of SEM. It has been found that the cooling process with the use of higher rates of cooling causes a size reduction of the structure in the outer layer and a reduction of thickness of both the intermediate diffusion layer and the whole coating by ca. 25 %.

  13. The superior cycling performance of the hydrothermal synthesized carbon-coated ZnO as anode material for zinc-nickel secondary cells

    Science.gov (United States)

    Feng, Zhaobin; Yang, Zhanhong; Huang, Jianhang; Xie, Xiaoe; Zhang, Zheng

    2015-02-01

    Carbon-coated ZnO is synthesized by the hydrothermal method. The X-ray diffraction (XRD), scanning electron microscope (SEM), high resolution transmission electron microscopy (HRTEM) and energy dispersive X-ray analysis (EDX) tests indicate that carbon is uniformly coated on the surface of the ZnO particle. And the crystal form of ZnO isn't changed. The effects of carbon layer on the electrochemical performances of ZnO have also been investigated by the charge/discharge cycling test, cyclic voltammetry (CV), Tafel polarization curves and electrochemical impedance spectroscope (EIS) tests. The CV curves at different scan rates exhibit that carbon-coated ZnO has the superior reversibility at high scan rate. The charge/discharge cycling tests under different charge/discharge rates show, even if at high-rate, the cycling performance and specific discharge capacity of carbon-coated ZnO are also superior to that of bare ZnO. The Tafel polarization curves and electrochemical impedance spectroscope (EIS) verify that the carbon layer can improve the anti-corrosion and charge-transfer performances of ZnO. The different rate experiments indicate that, compared with the increase of the conductivity, the effect of carbon layer on improving the anti-corrosion performance of ZnO plays a more dominating role in improving the electrochemical performances of ZnO at low charge/discharge rate.

  14. In vitro study of polycaprolactone/bioactive glass composite coatings on corrosion and bioactivity of pure Mg

    Science.gov (United States)

    Yang, Yuyun; Michalczyk, Carolin; Singer, Ferdinand; Virtanen, Sannakaisa; Boccaccini, Aldo R.

    2015-11-01

    The influence of the addition of nano-scaled bioactive glass (nBG) powder into polycaprolactone (PCL) coatings on the biodegradation and bioactivity of pure Mg was investigated in the present work. Scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), Fourier transform infrared spectroscopy (FTIR) and electrochemical methods were employed to characterize the morphology, chemical composition and anticorrosion properties of the coatings. The results indicate that nBG addition in PCL increases the degradation of PCL in physiological solution; depending on the amount of nBG in the composite coating, the barrier properties of PCL therefore can be modified. At the same time, the addition of nBG facilitates the formation of hydroxyapatite during 7 days immersion in simulated body fluid (SBF).

  15. Distinctive colonization of Bacillus sp. bacteria and the influence of the bacterial biofilm on electrochemical behaviors of aluminum coatings.

    Science.gov (United States)

    Abdoli, Leila; Suo, Xinkun; Li, Hua

    2016-09-01

    Formation of biofilm is usually essential for the development of biofouling and crucially impacts the corrosion of marine structures. Here we report the attachment behaviors of Bacillus sp. bacteria and subsequent formation of bacterial biofilm on stainless steel and thermal sprayed aluminum coatings in artificial seawater. The colonized bacteria accelerate the corrosion of the steel plates, and markedly enhance the anti-corrosion performances of the Al coatings in early growth stage of the bacterial biofilm. After 7days incubation, the biofilm formed on the steel is heterogeneous while exhibits homogeneous feature on the Al coating. Atomic force microscopy examination discloses inception of formation of local pitting on steel plates associated with significantly roughened surface. Electrochemical testing suggests that the impact of the bacterial biofilm on the corrosion behaviors of marine structures is not decided by the biofilm alone, it is instead attributed to synergistic influence by both the biofilm and physicochemical characteristics of the substratum materials. PMID:27289310

  16. High-Temperature Corrosion of Protective Coatings for Boiler Tubes in Thermal Power Plants

    Institute of Scientific and Technical Information of China (English)

    XU Lianyong; JING Hongyang; HUO Lixing

    2005-01-01

    High-temperature corrosion is a serious problem for the water-wall tubes of boilers used in thermal power plants. Oxidation, sulfidation and molten salt corrosion are main corrosion ways.Thereinto, the most severe corrosion occurs in molten salt corrosion environment. Materials rich in oxides formers, such as chromium and aluminum, are needed to resist corrosion in high-temperature and corrosive environment, but processability of such bulk alloys is very limited. High velocity electric arc spraying (HVAS) technology is adopted to produce coatings with high corrosion resistance. By comparison, NiCr (Ni-45Cr-4Ti) is recommended as a promising alloy coating for the water-wall tubes, which can even resist molten salt corrosion attack. In the study of corrosion mechanism, the modern material analysis methods, such as scanning electron microscopy (SEM), X-ray diffractometry (XRD) and energy dispersive spectrometry (EDS), are used. It is found that the corrosion resistances of NiCr and FeCrAI coatings are much better than that of 20g steel, that the NiCr coatings have the best anti-corrosion properties, and that the NiCr coatings have slightly lower pores than FeCrAI coatings.It is testified that corrosion resistance of coatings is mainly determined by chromium content, and the microstructure of a coating is as important as the chemical composition of the material. In addition, the fracture mechanisms of coatings in the cycle of heating and cooling are put forward. The difference of the thermal physical properties between coatings and base metals results in the thermal stress inside the coatings. Consequently, the coatings spall from the base metal.

  17. Influence of anti-corrosion additive on the performance, emission and engine component wear characteristics of an IDI diesel engine fueled with palm biodiesel

    International Nuclear Information System (INIS)

    Highlights: • Maximum engine performance was obtained at 2000 rpm for all fuel blends. • IRGALUBE 349 additive is enhances diesel engine performance. • Reduction of CO and NOx considerably using anti-corrosion additive except HC. • Engine wear decreases with using blended fuels with anti-corrosion additive. - Abstract: This study evaluates the effect of anti-corrosion additives such as 8% and 16% (vol.%) palm olein oil (PO) with ordinary diesel (OD) fuel on engine operation, emission behavior, engine part wear, and lubrication characteristics. This experiment was conducted on 4-cylinder and 4-stroke IDI diesel engine at different engine speed ranging from 1200 to 2800 RPM with 30% throttle setting under full load condition. The properties of the palm olein oil blends meet the ASTM D6751 and EN 14214 standards. At 2000 rpm, the experimental results revealed that the POD8A (0.2% Additive + 8% PO + 92% OD) and POD16A (0.2% Additive + 16% PO + 84% OD) blended fuels produced 0.5% and 0.51% higher brake power as well as 1.45% and 1.25% higher torque than same blends without additive, respectively. In comparison with ODF, the brake specific fuel consumption (BSFC) was found 1.8% and 3.1% higher for POD8A and POD16A blends, respectively. Anti-corrosion additive is found more effectual in enhancing the engine performance as such additive helps in timely ignition for complete burn in the combustion chamber. The results from engine emission indicated that POD8A and POD16A blended fuel reduced CO emissions by 11% and 6.6% and NOx emission by 2.5% and 1.09%, respectively in compared with OD fuel. Although HC emissions for all blended fuel and OD fuel increased at higher engine speed, the average HC emissions of all blended fuel were not higher than OD fuel. The application of anti-corrosion additives in POD blends reduced ferrous (Fe) wear debris concentration (WBC) by 17.3%. The reductions in WBC were about 16.1%, 10.8%, and 19.3%, 17.6% for copper (Cu) and aluminum

  18. Controllable growth of durable superhydrophobic coatings on a copper substrate via electrodeposition.

    Science.gov (United States)

    He, Ge; Lu, Shixiang; Xu, Wenguo; Szunerits, Sabine; Boukherroub, Rabah; Zhang, Haifeng

    2015-04-28

    Superhydrophobic coatings on a copper substrate are grown via electrodeposition followed by thermal annealing. The influence of the deposition potential, zinc ion concentration, deposition time, annealing temperature and annealing time on the wetting properties was systematically investigated. The coating electrodeposited at -1.35 V for 25 min and annealed at 190 °C for 60 min exhibited excellent superhydrophobicity with a contact angle as high as 170 ± 2° and a sliding angle of almost 0°. The water drop can fully bounce as a balloon when impinging such a solid surface, exhibiting excellent non-sticking properties. By adopting various characterization methods, it was demonstrated that the as-prepared superhydrophobic surfaces also exhibited properties of anticorrosion, antiabrasion, long-term stability and durability and large buoyancy force, which offer an effective strategy and promising industrial applications for fabricating superhydrophobic surfaces on various metallic materials. PMID:25821030

  19. Silica-coated carbonyl iron microsphere based magnetorheological fluid and its damping force characteristics

    Science.gov (United States)

    Liu, Y. D.; Lee, J.; Choi, S. B.; Choi, H. J.

    2013-06-01

    Silica-coated soft magnetic carbonyl iron (CI) particles with a reduced density and enhanced anti-corrosion properties compared to pristine CI were synthesized and applied as magneto-responsive particles in a magnetorheological (MR) fluid in this study. The MR fluids containing both pristine CI and silica-coated CI particles were injected into a custom-designed MR damper, and their damping characteristics, such as damping force as a function of time, displacement and velocity, were investigated, since vibration attenuation using mechanical damper systems is one of the main applications of MR fluids. Under the same magnetic field strength applied, the damping characteristics of the two MR fluids were observed to be directly related to their yield stresses.

  20. Morbus Coats

    Science.gov (United States)

    Förl, B.; Schmack, I.; Grossniklaus, H.E.; Rohrschneider, K.

    2010-01-01

    Der fortgeschrittene Morbus Coats stellt im Kleinkindalter eine der schwierigsten Differenzialdiagnosen zum Retinoblastom dar. Wir beschreiben die klinischen und histologischen Befunde zweier Jungen im Alter von 9 und 21 Monaten mit einseitiger Leukokorie. Trotz umfassender Diagnostik mittels Narkoseuntersuchung, MRT und Ultraschall konnte ein Retinoblastom nicht sicher ausgeschlossen werden, und es erfolgte eine Enukleation. Histologisch wurde die Diagnose eines Morbus Coats gesichert. Da eine differenzialdiagnostische Abgrenzung zwischen Morbus Coats und Retinoblastom schwierig sein kann, halten wir in zweifelhaften Fällen auch angesichts der eingeschränkten Visusprognose und potenzieller Sekundärkomplikationen beim fortgeschrittenen Morbus Coats eine Enukleation für indiziert. PMID:18299842

  1. Alternative environmentally friendly coatings for mild steel and electrogalvanized steel to be exposed to atmospheres

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, E.; Santos, D. [INETI - Inst. Nacional de Engenharia e Tecnologia Industrial / LTR, Lisboa (Portugal); Fragata, F. [CEPEL - Centro de Pesquizas de Energia Electrica, Cidade Univ., Rio de Janeiro, RJ (Brazil); Rincon, O. [Centro de Estudios de Corrosion, Univ. del Zulia, Maracaibo (Venezuela); Morcillo, M. [Centro Nacional de Investigaciones Metalurgicas, Madrid (Spain)

    2001-12-01

    The study of new paint systems that are less harmful to the environment and to man than traditional solvent-borne systems, but have identical anti-corrosive characteristics, is an issue of great interest at the present time. The authors of this work have taken advantage of the opportunity to use different natural atmospheres in the Ibero-American region to study the behaviour of new water-borne, high-solids and powder paint systems, with and without pre-treatment. The study has involved coatings exposure in 7 natural atmospheres and different laboratory accelerated tests. It was completed with scanning electron microscopy (SEM) observations, energy dispersive spectrometry (EDS) analysis, and adhesion, water up-take and electrochemical measurements. It has been concluded that water-borne acrylic paint systems incorporating primers pigmented with zinc phosphate and others show deficient behaviour in marine atmospheres, but better behaviour in industrial atmospheres. In marine atmospheres, water-borne epoxy paint systems, including zinc-rich primers, together with epoxy and epoxy-polyurethane high-solids paint systems, present the most efficient anti-corrosive behaviour. The coatings obtained with epoxy and epoxy-polyester powder paints only show good behaviour, when applied on an adequate pre-treatment, in atmospheres of low to medium corrosivity category (C{sub 2}-C{sub 3}). Finally, the best correlation was observed between the results of natural exposure in marine atmospheres, salt spray and water up-take measurements. It was not possible to verify good correlation between natural exposure and prohesion, adhesion and electrochemical tests. The latter are highly sensitive to the chemical nature of coatings, and seem to be significantly more useful when comparing coatings with more identical nature. (orig.)

  2. 遗体防腐处理方法%The Methods for Mortal Remains Anti-corrosion

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

      为了促进医学教学与遗体器官捐献事业发展,我国已经在中国红十字会的引领下开展遗体捐献与接收工作。本文叙述遗体接收利用单位对遗体的防腐处理方法,在处理过程中可能遇到的问题与处理方式。期待更多医疗卫生相关单位掌握防腐处理技术,促进我国遗体捐献工作。%In order to promote the development of medical teach-ing and organ donation of the body, we have carried out under the lead of the Red Cross Society of China remains donation and re-ceipt of work. This article describes receiving unit for anticorro-sion treatment of the remains of the body, and may encounter problems during the process and approach. Looking forward to more access to preservative treatment technology of medical and health, promoting body donation in China.

  3. Spectroscopic examinations, antimicrobial and anti-corrosive evaluations of polyurethanes synthesized from Thevetia peruviana seed oil

    Directory of Open Access Journals (Sweden)

    T. O. Siyanbola

    2016-03-01

    Full Text Available Seed oil based polyurethane resins were synthesized from underutilized plant seedlings of Thevetia peruviana (yellow oleanda. The seed oil was converted to partial glycerides (PG polyol using calcium oxide as catalyst. The polyol was treated with varying ratios of isophorone diisocyanate (IPDI in order to synthesize partial glyceride urethanes (PGU films. The PG intermediate and PGU products were characterized using FT-IR, 1H-NMR and 13C-NMR. Physico-chemical parameters like acid value, hydroxyl value, viscosity and refractive index were also examined. Corrosion stability of coated panels was studied in the salt spray chamber. Thermal stability and antimicrobial study of the films were also evaluated.

  4. Corrosion behavior of modified nano carbon black/epoxy coating in accelerated conditions

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • By using SDS as a surfactant, nano particles of CB were uniformly dispersed. • CB nanoparticle in the epoxy coating improved the corrosion resistance of the coating. • By addition of CB nanoparticles to the epoxy diffusion ions and water became limited. • The dominance of barrier mechanism was proved by calculation of the diffusion coefficients. - Abstract: The electrochemical behavior and anticorrosion properties of modified carbon black (CB) nanoparticles in epoxy coatings were investigated in accelerated conditions. Nanoparticles of CB were modified by sodium dodecyl sulfate (SDS) as surfactant. Dispersion of nanoparticles into epoxy was confirmed by Transmission Electron Microscopy (TEM). The accelerated condition was prepared at 65 °C. CB nanoparticles improved corrosion resistance of the epoxy coating. The optimum concentration of CB in the epoxy coating was 0.75 wt%. Results showed that the CB hinder the corrosion due to its barrier properties. CB can decrease the diffusion coefficient of water in the coating with filling the micropores

  5. Corrosion behavior of modified nano carbon black/epoxy coating in accelerated conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ghasemi-Kahrizsangi, Ahmad; Shariatpanahi, Homeira, E-mail: shariatpanahih@ripi.ir; Neshati, Jaber; Akbarinezhad, Esmaeil

    2015-03-15

    Graphical abstract: - Highlights: • By using SDS as a surfactant, nano particles of CB were uniformly dispersed. • CB nanoparticle in the epoxy coating improved the corrosion resistance of the coating. • By addition of CB nanoparticles to the epoxy diffusion ions and water became limited. • The dominance of barrier mechanism was proved by calculation of the diffusion coefficients. - Abstract: The electrochemical behavior and anticorrosion properties of modified carbon black (CB) nanoparticles in epoxy coatings were investigated in accelerated conditions. Nanoparticles of CB were modified by sodium dodecyl sulfate (SDS) as surfactant. Dispersion of nanoparticles into epoxy was confirmed by Transmission Electron Microscopy (TEM). The accelerated condition was prepared at 65 °C. CB nanoparticles improved corrosion resistance of the epoxy coating. The optimum concentration of CB in the epoxy coating was 0.75 wt%. Results showed that the CB hinder the corrosion due to its barrier properties. CB can decrease the diffusion coefficient of water in the coating with filling the micropores.

  6. Ti Coating on Magnesium Alloy by Arc-Added Glow Discharge Plasma Penetrating Technique

    Institute of Scientific and Technical Information of China (English)

    CUICai-e; MIAOQiang; PANJun-de; ZHANGPing-ze; ZHANGGao-hui

    2004-01-01

    Arc-added glow discharge plasma penetrating technique is a new surface coating method. With the help of vacuum arc discharge, a cold cathode arc source continually emits ion beams of coating elements with high currency density and high ionizing ratio. As the ion bombard and diffusion working on, the surface of the parts form deposited layer, penetrated layer and hybrid layer. Under lab condition, a commercial magnesium alloy Az91 had been coated with Ti film layer with the aim of improving its' anti-corrosion performance. This paper mainly summarized our studies on the testing and analyzing of the coating layer. The composition and microstructure of the coating layer had been analyzed by means of X-ray diffraction (XRD) and glow discharge spectrum (GDS), and the surface appearance had been surveyed by scanning electronic microscope (SEM). The adhesion strength between film and matrix had been evaluated by experiments of sticking-tearing. The results indicated that the coated layer on magnesium alloy were homogeneous, dense and robustly adhered.

  7. Antibacterial characteristics of electroless plating Ni–P–TiO{sub 2} coatings

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Qi, E-mail: Q.Zhao@dundee.ac.uk [Department of Mechanical Engineering, University of Dundee, DD1 4HN (United Kingdom); Liu, Chen; Su, Xueju; Zhang, Shuai; Song, Wei; Wang, Su [Department of Mechanical Engineering, University of Dundee, DD1 4HN (United Kingdom); Ning, Guiling, E-mail: ninggl@dlut.edu.cn [State Key Laboratory of Fine Chemicals and School of Chemical Engineering, Dalian University of Technology, 2 Linggong Road, Dalian 116024 (China); Ye, Junwei; Lin, Yuan; Gong, Weitao [State Key Laboratory of Fine Chemicals and School of Chemical Engineering, Dalian University of Technology, 2 Linggong Road, Dalian 116024 (China)

    2013-06-01

    Electroless Ni–P coatings have been widely used in the chemical, mechanical and electronic industries due to their excellent corrosion and wear resistance. Many studies reported that the incorporation of nano-sized particles TiO{sub 2} into Ni–P matrix greatly improved their anti-corrosion and anti-wear resistance. However no studies have been reported on their anti-bacterial property. In this paper, the Ni–P–TiO{sub 2} nano-composite coatings were prepared on stainless steel 316L using electroless plating technique. The experimental results showed that the Ni–P–TiO{sub 2} coatings reduced the adhesion of three bacterial strains (Pseudomonas fluorescens, Cobetia and Vibrio) by up to 75% and 70% respectively, as compared with stainless steel and Ni–P coatings. The electron donor surface energy of the Ni–P–TiO{sub 2} coatings increased significantly with increasing TiO{sub 2} content after UV irradiation. The number of adhered bacteria decreased with increasing electron donor surface energy of the coatings.

  8. Facile approach in the development of icephobic hierarchically textured coatings as corrosion barrier

    Energy Technology Data Exchange (ETDEWEB)

    Momen, G., E-mail: gmomen@uqac.ca; Farzaneh, M.

    2014-04-01

    Highlights: • A superhydrophobic coating is developed via a simple environmental-friendly method. • This coating can be used on the surface of various metals such as copper, magnesium. • The superhydrophobic aluminum surface showed the excellent corrosion resistance. • The fabricated surface revealed a drastically reduction of ice adhesion strength. • Such surfaces can advantageously be used in cold climate regions. - Abstract: An anti-corrosion superhydrophobic film with water contact angle greater than 160° on aluminum alloy 6061 substrate was fabricated simply through the spin-coating method applied to Al{sub 2}O{sub 3} nanoparticles doped in silicone rubber solution. The as-obtained sample was characterized by scanning electron microscopy (SEM) and water contact angle/surface energy measurement. The corrosion behaviour of such coating in the NaCl solutions was investigated using the potentiodynamic polarization. The results show that the corrosion resistance of the developed superhydrophobic surface is improved greatly due to the composite wetting states or interfaces with numerous air pockets between its surface and the NaCl solution. This superhydrophobic coating could serve as an effective barrier against aggressive medium. Ice adhesion strength of the as-prepared superhydrophobic coating was also evaluated by measuring its ice adhesion force which was found to have reduced by 4.8 times compared to that of aluminum substrate as reference test.

  9. The Role of interfacial layers on the performance of an epoxy / polyester powder coated Aluminium Alloy

    International Nuclear Information System (INIS)

    The influence of polyacrylic acid and a blend of polyacrylic acid with hexa fluorozirconic acid treatments on the performance of an epoxy/polyester powder coating on a 1050 Al substrate has been studied and compared to the performance of the same system using a so-called chromate/phosphate conversion coating. The chemical interactions between pretreatments and Al substrates were examined using FTIR spectroscopy and various accelerated test methods were also employed. Two mechanical adhesion measurement methods were used under wet and dry conditions, namely a vertical pull-off test in the dry state and the tape test under dry conditions. The water permeation of the differently pretreated powder coated samples was studied using a capacitance measurement method. FTIR results showed two modes of interaction; namely ionic and complex formation between COO- and Al3+ Various experiments revealed that polyacrylic acid improved only the dry adhesion but as a standing alone treatment it did not provide an overall improvement in anti-corrosive performance. The water uptake measurements proved that pretreatment does not considerably affect the properties of the coatings during water permeation stage. The use of various techniques revealed that relatively good performance of powder coating is due to a high ohmic resistance of the coating prior to and after saturation with water, reasonably low water solubility and good adhesion to the substrate

  10. Facile approach in the development of icephobic hierarchically textured coatings as corrosion barrier

    International Nuclear Information System (INIS)

    Highlights: • A superhydrophobic coating is developed via a simple environmental-friendly method. • This coating can be used on the surface of various metals such as copper, magnesium. • The superhydrophobic aluminum surface showed the excellent corrosion resistance. • The fabricated surface revealed a drastically reduction of ice adhesion strength. • Such surfaces can advantageously be used in cold climate regions. - Abstract: An anti-corrosion superhydrophobic film with water contact angle greater than 160° on aluminum alloy 6061 substrate was fabricated simply through the spin-coating method applied to Al2O3 nanoparticles doped in silicone rubber solution. The as-obtained sample was characterized by scanning electron microscopy (SEM) and water contact angle/surface energy measurement. The corrosion behaviour of such coating in the NaCl solutions was investigated using the potentiodynamic polarization. The results show that the corrosion resistance of the developed superhydrophobic surface is improved greatly due to the composite wetting states or interfaces with numerous air pockets between its surface and the NaCl solution. This superhydrophobic coating could serve as an effective barrier against aggressive medium. Ice adhesion strength of the as-prepared superhydrophobic coating was also evaluated by measuring its ice adhesion force which was found to have reduced by 4.8 times compared to that of aluminum substrate as reference test

  11. Antibacterial characteristics of electroless plating Ni-P-TiO2 coatings

    Science.gov (United States)

    Zhao, Qi; Liu, Chen; Su, Xueju; Zhang, Shuai; Song, Wei; Wang, Su; Ning, Guiling; Ye, Junwei; Lin, Yuan; Gong, Weitao

    2013-06-01

    Electroless Ni-P coatings have been widely used in the chemical, mechanical and electronic industries due to their excellent corrosion and wear resistance. Many studies reported that the incorporation of nano-sized particles TiO2 into Ni-P matrix greatly improved their anti-corrosion and anti-wear resistance. However no studies have been reported on their anti-bacterial property. In this paper, the Ni-P-TiO2 nano-composite coatings were prepared on stainless steel 316L using electroless plating technique. The experimental results showed that the Ni-P-TiO2 coatings reduced the adhesion of three bacterial strains (Pseudomonas fluorescens, Cobetia and Vibrio) by up to 75% and 70% respectively, as compared with stainless steel and Ni-P coatings. The electron donor surface energy of the Ni-P-TiO2 coatings increased significantly with increasing TiO2 content after UV irradiation. The number of adhered bacteria decreased with increasing electron donor surface energy of the coatings.

  12. Facile preparation of superamphiphobic epoxy resin/modified poly(vinylidene fluoride)/fluorinated ethylene propylene composite coating with corrosion/wear-resistance

    Science.gov (United States)

    Wang, Huaiyuan; Liu, Zhanjian; Wang, Enqun; Zhang, Xiguang; Yuan, Ruixia; Wu, Shiqi; Zhu, Yanji

    2015-12-01

    A robust superamphiphobic epoxy resin (EP)/modified poly(vinylidene fluoride) (MPVDF)/fluorinated ethylene propylene (FEP) composite coating has been prepared through the combination of chemical modification and spraying technique. Nanometer silica (SiO2, 2.5 wt.%) and carbon nanotubes (CNTs, 2.5 wt.%) were added in the coating to construct the necessary reticulate papillae structures for superamphiphobic surface. The prepared EP composite coating demonstrated high static contact angles (166°, 155°) and low sliding angles (3°, 5°) to water and glycerol, respectively. Moreover, the prepared coating can also retain superhydrophobicity under strongly acidic and alkaline conditions. The brittleness of EP can be avoided by introducing the malleable MPVDF. The wear life of the EP composite coating with 25 wt.% FEP was improved to 18 times of the pure EP coating. The increased wear life of the coating can be attributed to the designed nano/micro structures, the self-lubrication of FEP and the chemical reaction between EP and MPVDF. The anti-corrosion performance of the coatings was investigated in 3.5% NaCl solution using potentiodynamic polarization. The results showed that the prepared superamphiphobic composite coating was most effective in corrosion resistance, primarily due to the barrier effect for the diffusion of O2 and H2O molecules. It is believed that this robust superamphiphobic EP/MPVDF/FEP composite coating prepared by the facile spray method can pave a way for the large-scale application in pipeline transport.

  13. Sprayed coatings

    Science.gov (United States)

    Steffens, H. D.

    1980-03-01

    Thermal spraying is shown to be an efficient means for the protection of surface areas against elevated temperature, wear, corrosion, hot gas corrosion, and erosion in structural aircraft components. Particularly in jet engines, numerous parts are coated by flame, detonation, or plasma spraying techniques. The applied methods of flame, detonation, and plasma spraying are explained, as well as electric arc spraying. Possibilities for spray coatings which meet aircraft service requirements are discussed, as well as methods for quality control, especially nondestructive test methods. In particular, coating characteristics and properties obtained by different spray methods are described, and special attention is paid to low pressure plasma spraying.

  14. Mechanism of (NH4)S2O8 to enhance the anti-corrosion performance of Mo-Ce inhibitor on X80 steel in acid solution

    International Nuclear Information System (INIS)

    Highlights: • The 1000 mg/L Na2MoO4 and 500 mg/L Ce(NO3)3 has best synergistic effect. • The (NH4)2S2O8 made the valence transformation of cerium (Ce3+ → Ce4+) come true. • The anti-corrosion performance of Mo-Ce inhibitor was improved by (NH4)2S2O8. • The coordination ability of inhibitor complexes was improved by (NH4)2S2O8. • The bonding force and adsorption between inhibitor and steel surface was enhanced. - Abstract: Ce(NO3)3 and Na2MoO4 are adopted to form (Mo-Ce) composite corrosion inhibitor in allusion to the corrosion problem of steel in acidic conditions. The experimental results showed that the anticorrosion effects were enhanced and the inhibition efficiencies were increased by (NH4)2S2O8. The reason of enhancement is the increase of coordination bonds amount between Ce4+ and MoO42−, the augment of combining sites of interface between anti-corrosion film and steel, and the reinforce of adsorption caused by the transformation of Ce3+ to Ce4+ by oxidants. The process and conditions for transformation of Ce3+ to Ce4+ and formation of complexes are discussed. The related thermodynamic and kinetic parameters are calculated and the possibility for (NH4)2S2O8 to improve the performance of Mo-Ce corrosion inhibitor is proved

  15. Hard coatings

    OpenAIRE

    Dan, J.; Boving, H.; Hintermann, H.

    1993-01-01

    Hard, wear resistant and low friction coatings are presently produced on a world-wide basis, by different processes such as electrochemical or electroless methods, spray technologies, thermochemical, CVD and PVD. Some of the most advanced processes, especially those dedicated to thin film depositions, basically belong to CVD or PVD technologies, and will be looked at in more detail. The hard coatings mainly consist of oxides, nitrides, carbides, borides or carbon. Over the years, many process...

  16. 大型天线防腐技术%Anticorrosion technology for large antenna

    Institute of Scientific and Technical Information of China (English)

    董长胜; 张伟明; 王建宅; 银秋华; 黄晓群; 任兵锐; 张亚林; 曹江涛

    2014-01-01

    Large Antennas have been widely used in the aerospace ,deep‐space exploration and broadcast ,w hich are essential in the communication .T hey are fabricated by metal ,w hich can be easily corroded .Corrosion will deteriorate the appearance and performance ,even cause the security problem .By analyzing the necessary ,theory and influence factors of antenna corro‐sion ,many methods are proposed ,w hich contains optimizing materials ,structures ,designs , coatings ,and transportation .%大型天线广泛地应用在航空航天、深空探测、广播通信等领域,成为信息传递必不可少的设备。其多采用金属材料制造,因此在长期的室外工作环境下,极易发生腐蚀。金属材料的腐蚀将严重影响天线的性能和外观,甚至会产生人员与设备的安全问题。本文结合实际情况通过分析天线腐蚀的必要性、腐蚀机理和影响因素,结合实际情况为天线的防腐提供了优化材料、结构、加工工艺设计、喷镀金属涂层防护、涂料涂装防护、运输安装过程的防护、已损坏防护层的修复等方法,实现天线的长效防腐。

  17. Corrosion of Magnesium-Aluminum Alloys with Al-11Si/SiC Thermal Spray Composite Coatings in Chloride Solution

    Science.gov (United States)

    Arrabal, R.; Pardo, A.; Merino, M. C.; Mohedano, M.; Casajús, P.; Matykina, E.

    2011-03-01

    Depositions of Al-11Si coatings reinforced with 5, 15, and 30 vol.% SiC particles (SiCp) were performed onto AZ31, AZ80, and AZ91D magnesium alloys. The influence of substrate composition and SiCp proportion on the anti-corrosion properties of composite coatings was evaluated using DC and AC electrochemical measurements in 3.5 wt.% NaCl solution at 22 °C. The as-sprayed coatings were permeable to the saline solution, and galvanic corrosion occurred at the substrate/coating interface after immersion in the saline solution for a few hours. The addition of SiCp yielded coatings with higher porosity and less effectiveness against corrosion. The application of a cold-pressing post-treatment produced denser coatings with reduced surface roughness, improved hardness, and superior corrosion resistance. However, galvanic corrosion was observed after several days of immersion because of penetration of the 3.5 wt.% NaCl solution through the remaining pores in the coatings.

  18. Effect of rare element cerium on the morphology and corrosion resistance of electro-less Ni-P coatings

    Directory of Open Access Journals (Sweden)

    Fu Chuan-qi

    2015-01-01

    Full Text Available This paper reports an experimental study on the microstructure and corrosion resistance of electro-less Ni-P coatings with increasing content of the rare element cerium (Ce. Surface morphology and the composition of the electro-less Ni-P coatings were studied by scanning electron microscope (SEM, X-ray energy dispersed analysis (EDS and X-ray diffraction analysis (XRD. Hardness and Adhesive force are researched by a HX-200 Vickers diamond indenter micro-hardness tester. Furthermore, we study the adhesive force by using the Revetest scratch tester. We get the possession of Ce amorphous Ni-P coatings which has excellent properties in anti-corrosion. The effect of the rare element cerium concentration on corrosion resistance of the coatings was evaluated in the groundwater immersion test and porosity test, respectively. The results indicated that added little the rare element cerium into the plating bath increased the phosphorus content of the coatings, decreased the corrosion rates, it also decreases the porosity of the amorphous Ni-P coatings. The lowest corrosion rates of the amorphous Ni-P coatings in groundwater immersion test is 4.1 um · h-1, at the rare element cerium concentration of 0.12g · L-1.

  19. Fabrication and characterization of Ni–Zr composite coatings using electrodepositing technique

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Fei [School of Materials Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Jiang, Chuanhai, E-mail: chuanhaijiang1963@163.com [School of Materials Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Zhang, Zhongquan [School of Materials Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Muttini, Enzo [ICMMO/LEMHE, UMR 8182, Université Paris-Sud 11, Orsay Cedex 91405 (France); Fu, Peng; Zhao, Yuantao [School of Materials Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Ji, Vincent [ICMMO/LEMHE, UMR 8182, Université Paris-Sud 11, Orsay Cedex 91405 (France)

    2015-06-25

    Highlights: • A novel Ni–Zr coatings with higher Zr content were fabricated. • Increasing Zr content resulted in the (1 1 1) preferred orientation. • The (1 1 1) preferred orientation increased the corrosion resistance. • Relationship between corrosion and Zr content, grain and texture was discussed. - Abstract: The main goal of this research is to prepare Ni–Zr composite coatings with different amounts of Zr micro-particles by using electrodeposition technology. Different characterization techniques including X-ray diffractometer (XRD), field emission scanning electron microscopy (FESEM) and Energy Dispersive X-ray Spectroscopy (EDX) were used to investigate the effects of Zr micro-particle contents on the surface morphology, texture, grain size, residual stress and hardness of the Ni–Zr composite coatings. The electrochemical impedance and potentiodynamic polarization measurements were also used to examine the corrosion resistance. As the Zr contents in the Ni–Zr composite coating increased, the (2 0 0) texture changed to the (1 1 1) texture, the grain size decreased, the residual stress and hardness increased. The anti-corrosion properties of the Ni–Zr composite coatings could be linked to several reasons such as the amount of Zr micro-particles in the deposits, a decrease in grain size, and a change in the texture of the deposits.

  20. Electrochemical corrosion protection studies of aniline-capped aniline trimer-based electroactive polyurethane coatings

    International Nuclear Information System (INIS)

    In this paper, the successful preparation of electroactive polyurethane (EPU) coatings containing amine-capped aniline trimer (ACAT) is presented for the first time. To accomplish this, ACAT was synthesized by carrying out oxidative coupling reactions between aniline and para-phenylenediamine, after which it was characterized through Fourier-transformation infrared and UV–vis spectroscopy. Subsequently, a polyurethane (PU) prepolymer was prepared by polymerizing diisocyanate of 4,4-methylene-bis(cyclohexylisocyanate), diol of polycaprolactone, and triol of phloroglucinol at 60 °C for 3 h. EPU was then produced by allowing the as-prepared polyurethane prepolymer to react with ACAT under suitable conditions. Non-electroactive polyurethane (NEPU) coating was also prepared for the control experiments. Based on a series of electrochemical corrosion measurements, EPU in the form of a coating was found to possess a clearly enhanced corrosion protection effect when compared to PU. The observed enhancement of the anticorrosion effect of EPU on a metallic substrate when compared to that of NEPU may have been caused by the redox catalytic capability of ACAT present in EPU, inducing the formation of a densely passive metal oxide layer (i.e., Fe2O3 and Fe3O4), as indicated by the results of scanning electron microscopy and electron spectroscopy for chemical analysis. The redox behavior of the EPU coatings was further analyzed and compared to that of the NEPU coating by cyclic voltammetric (CV) studies.

  1. Microstructure and properties of duplex (Ti:N)-DLC/MAO coating on magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Wei; Ke, Peiling [Ningbo Key Laboratory of Marine Protection Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Fang, Yong [Sir Run Run Shaw Hospital, School of Medicine, Zhe Jiang University, Zhejiang 310016 (China); Zheng, He [Ningbo Key Laboratory of Marine Protection Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Wang, Aiying, E-mail: aywang@nimte.ac.cn [Ningbo Key Laboratory of Marine Protection Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China)

    2013-04-01

    Ti and N co-doped diamond-like carbon ((Ti:N)-DLC) film was deposited on the MAO coated substrate using a hybrid beam deposition system, which consists of a DC magnetron sputtering of Ti target and a linear ion source (LIS) with C{sub 2}H{sub 2} and N{sub 2} precursor gas. The microstructure and properties of the duplex (Ti:N)-DLC/MAO coating were investigated. Results indicate that the (Ti:N)-DLC top film with TiN crystalline phase was formed. Ti and N co-doping resulted in the increasing I{sub D}/I{sub G} ratio. The significant improvement in the wear and corrosion resistance of duplex (Ti:N)-DLC/MAO coating was mainly attributed to the increased binding strength, lubrication characteristics and chemical inertness of (Ti:N)-DLC top film. The superior low-friction and anti-corrosion properties of duplex (Ti:N)-DLC/MAO coating make it a good candidate as protective coating on magnesium alloy.

  2. Microstructure and properties of duplex (Ti:N)-DLC/MAO coating on magnesium alloy

    Science.gov (United States)

    Yang, Wei; Ke, Peiling; Fang, Yong; Zheng, He; Wang, Aiying

    2013-04-01

    Ti and N co-doped diamond-like carbon ((Ti:N)-DLC) film was deposited on the MAO coated substrate using a hybrid beam deposition system, which consists of a DC magnetron sputtering of Ti target and a linear ion source (LIS) with C2H2 and N2 precursor gas. The microstructure and properties of the duplex (Ti:N)-DLC/MAO coating were investigated. Results indicate that the (Ti:N)-DLC top film with TiN crystalline phase was formed. Ti and N co-doping resulted in the increasing ID/IG ratio. The significant improvement in the wear and corrosion resistance of duplex (Ti:N)-DLC/MAO coating was mainly attributed to the increased binding strength, lubrication characteristics and chemical inertness of (Ti:N)-DLC top film. The superior low-friction and anti-corrosion properties of duplex (Ti:N)-DLC/MAO coating make it a good candidate as protective coating on magnesium alloy.

  3. Corrosion behaviour in saline environments of single-layer titanium and aluminium coatings, and of Ti/Al alternated multi-layers elaborated by a multi-beam PVD technique

    International Nuclear Information System (INIS)

    This research thesis reports the characterization of anti-corrosion titanium and aluminium coatings deposited on a 35CD4 steel under the form of mono-metallic layers or alternated Ti/Al multi-layers, and obtained by a multibeam PVD technique. The influence of different parameters is studied: single-layer thickness (5, 15 or 30 micro-metres), multi-layer distribution (5 to 6) and substrate (smooth or threaded). Layer nature and microstructure are studied by optical microscopy and scanning electron microscopy (SEM), as well as corrosion toughness in aqueous saline environments. Coated threaded samples have been studied after tightening tests. It appears that titanium layers are denser and more uniform than aluminium layers, and that multi-layer coatings provide a better protection than single-layer coatings. The best behaviour is obtained when titanium is in contact with steel, and aluminium is the outer layer in contact with the corroding environment

  4. Wear and Corrosion Resistance of CrN-based Coatings Deposited by R.F Magnetron Sputtering

    Directory of Open Access Journals (Sweden)

    K. Bouzid

    2015-03-01

    Full Text Available A comparative study was conducted to evaluate the performances against wear and corrosion of CrN, CrMoN, CrZrN, CrVN single layer thin films. The latest are synthesized onto steel substrates (DIN 90CrMoV8, using R.F reactive magnetron co-sputtering. The experimental work was achieved using ball-on-disc configuration in dry conditions against WC balls. The main conclusions are: (i electrochemical tests in 0.3 wt.% NaCl solution indicated that CrZrN are improved anticorrosion performance when compared to CrN, while CrMoN demonstrated a poor corrosion resistance;(ii the CrN coating presents the better tribological properties when compared to the ternary nitride coatings.

  5. Hard coatings

    International Nuclear Information System (INIS)

    Hard, wear resistant and low friction coatings are presently produced on a world-wide basis, by different processes such as electrochemical or electroless methods, spray technologies, thermochemical, CVD and PVD. Some of the most advanced processes, especially those dedicated to thin film depositions, basically belong to CVD or PVD technologies, and will be looked at in more detail. The hard coatings mainly consist of oxides, nitrides, carbides, borides or carbon. Over the years, many processes have been developed which are variations and/or combinations of the basic CVD and PVD methods. The main difference between these two families of deposition techniques is that the CVD is an elevated temperature process (≥ 700 C), while the PVD on the contrary, is rather a low temperature process (≤ 500 C); this of course influences the choice of substrates and properties of the coating/substrate systems. Fundamental aspects of the vapor phase deposition techniques and some of their influences on coating properties will be discussed, as well as the very important interactions between deposit and substrate: diffusions, internal stress, etc. Advantages and limitations of CVD and PVD respectively will briefly be reviewed and examples of applications of the layers will be given. Parallel to the development and permanent updating of surface modification technologies, an effort was made to create novel characterisation methods. A close look will be given to the coating adherence control by means of the scratch test, at the coating hardness measurement by means of nanoindentation, at the coating wear resistance by means of a pin-on-disc tribometer, and at the surface quality evaluation by Atomic Force Microscopy (AFM). Finally, main important trends will be highlighted. (orig.)

  6. The influence of liquid Pb-Bi on the anti-corrosion behavior of Fe3O4: a first-principles study.

    Science.gov (United States)

    Li, Dongdong; Qu, Bingyan; He, H Y; Zhang, Y G; Xu, Yichun; Pan, B C; Zhou, Rulong

    2016-03-01

    In this work, the influence of Pb and Bi atoms on the anti-corrosion behavior of the oxide film (Fe3O4) formed on steel surface is investigated based on first-principles calculations. Through calculations of the formation energies, we find that Pb and Bi atoms can promote the formation of point defects, such as interstitial atoms and vacancies in Fe3O4. Besides, the effects of the concentration of Pb (or Bi) and pressure on the formation of these defects are also studied. Our results depict that a high density of Pb (or Bi) and compression pressure can promote the formation of defects in Fe3O4 significantly. Furthermore, the energy barriers for Pb and Bi atom migration in Fe3O4 are also estimated using the climbing image nudge elastic band (CI-NEB) method, which implies that Pb and Bi can diffuse more easily in Fe3O4 compared to Fe. Our results reveal the underlying mechanism of how Pb and Bi influence the anti-corrosion ability of oxide films in an accelerate driven system (ADS). It is instructive for improving the corrosion resistance of the oxide films in the ADS. PMID:26912208

  7. [Volume chemistry-ultraviolet spectrum differential method for determining the oxygen content in anti-corrosion copper powder with surface film consisting of benzotriazole].

    Science.gov (United States)

    Zhang, Tai-ming; Ding, Feng; Liang, Yi-zeng

    2006-11-01

    A method for determining the oxygen content in anti-corrosion copper powder with benzotriazole inhibitor surface film was established and the ultraviolet spectra of benzotriazole under various conditions were studied. The maximum absorption was at lamdamax=273 nm, and the temperature did not influence the absorption intensity at normal temperature. The linear range of concentration was 0-2.2 microg x mL(-1), the detection limit was 0.02 microg x mL(-1), and the apparent molar absorptivity of benzotriazole was epsilon = 5.41 x 10(4) L x mol(-1) x cm(-1) at 273 nm. Because the anti-corrosion copper powder consisted of copper metal, copper oxide and benzotriazole protecting film, the Cu and BTA contents of the powder were determined through EDTA titration and ultraviolet spectrophotometry, respectively, after the samples were decomposed with HCl and H2O2, and the oxygen content of the powder was calculated by differential method. The instruments are simple, the method is economical, and the manipulation is convenient. The standard deviation is 1.7%, and the differentiation coefficient is 7.6%. In conjunction with the application of the national standard method, the oxygen contents before and after the formation of the protecting film of the electrolyte copper powder were comparatively analyzed with satisfactory results. PMID:17260767

  8. Smart pigging - a contribution to the monitoring of the anti-corrosion protection systems on pig-inspectable high-pressure gas transmission pipelines; Intelligente Molchung - ein Beitrag zur Ueberwachung des Korrosionsschutzes molchbarer Gashochdruckleitungen

    Energy Technology Data Exchange (ETDEWEB)

    Ahlers, M.; Schoeneich, H.G. [Ruhrgas AG, Essen (Germany). Kompetenz-Center Korrosionsschutz

    2000-07-01

    High-pressure gas transmission pipelines installed underground are exposed to the risk of external corrosion. The application of a sheathing (passive protection) and, since the 1950s, the installation of a cathodic anti-corrosion protection system, provide pipelines with effective protection against this danger. In the past, the effectiveness of cathodic anti-corrosion protection systems was verified by means of intensive measuring and re-measuring cycles. It became apparent that points of damage to the sheathing were protected in the majority of cases against corrosion by the cathodic anti-corrosion protection system. There are, however, particular design circumstances and ambient conditions which can make this anti-corrosion protection concept either partially or completely ineffective. The use of smart pigs for inspection of pig-inspectable gas transmission pipelines makes it possible to detect and eliminate these weak points. (orig.) [German] Gashochdruckleitungen, die im Erdboden verlegt werden, unterliegen einer Gefaehrdung durch Aussenkorrosion. Durch eine Umhuellung (passiver Schutz) und seit den 50er Jahren durch die Einrichtung des kathodischen Korrosionsschutzes (aktiver Schutz) sind die Leitungen gegen diese Gefaehrdung wirkungsvoll geschuetzt. In der Vergangenheit wurde die Ueberpruefung der Wirksamkeit des kathodischen Korrosionsschutzes durch Intensivmessungen und Nachmessungen sichergestellt. Dabei zeigte sich, dass in der ueberwiegenden Zahl Umhuellungsbeschaedigungen durch den kathodischen Korrosionsschutz gegen Korrosion geschuetzt sind. Es gibt jedoch besondere konstruktive oder Umgebungsbedingungen, die dieses Korrosionsschuzkonzept teilweise oder vollstaendig unwirksam werden lassen. Mit dem Einsatz von intelligenten Molchen zur Inspektion molchbarer Gastransportleitungen koennen diese Schwachstellen erkannt und beseitigt werden. (orig.)

  9. Fabrication of TiO2-SiO2 bioceramic coatings on Ti alloy and its synergetic effect on biocompatibility and corrosion resistance.

    Science.gov (United States)

    Mumjitha, M; Raj, V

    2015-06-01

    Most of the research work focussed on fabricating an implant material with an ideal combination of potential bioactivity on the surface and striking mechanical property of bulk in one elementary operation. Interwoven with above concept, SiO2 incorporated nanostructured titania coatings were fabricated on Ti alloy by anodization using sodium silico fluoride electrolyte (SSF). The coatings were characterized by SEM, EDS, AFM, XRD and AT-FTIR techniques. The bioactivity and biocompatibility of the anodic coatings were also investigated. The AT-FTIR, EDS and XRD studies confirm the incorporation of SiO2 into TiO2 coating was confirmed by EDS, XRD and AT-FTIR techniques. The coating formed at the optimum conditions displays a dome like structure with nano flake morphology with maximum mechanical and anticorrosion properties. AFM analysis inferred that the surface roughness of the ceramic coating is higher compared to the pure titania. The SBF test and cell adhesion results predicted that SiO2 incorporated TiO2 coating is superior in their bioactivity compared to TiO2 coating. PMID:25817608

  10. Porous tantalum coatings prepared by vacuum plasma spraying enhance bmscs osteogenic differentiation and bone regeneration in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Ze Tang

    Full Text Available Tantalum, as a potential metallic implant biomaterial, is attracting more and more attention because of its excellent anticorrosion and biocompatibility. However, its significantly high elastic modulus and large mechanical incompatibility with bone tissue make it unsuitable for load-bearing implants. In this study, porous tantalum coatings were first successfully fabricated on titanium substrates by vacuum plasma spraying (VPS, which would exert the excellent biocompatibility of tantalum and alleviate the elastic modulus of tantalum for bone tissue. We evaluated cytocompatibility and osteogenesis activity of the porous tantalum coatings using human bone marrow stromal cells (hBMSCs and its ability to repair rabbit femur bone defects. The morphology and actin cytoskeletons of hBMSCs were observed via electron microscopy and confocal, and the cell viability, proliferation and osteogenic differentiation potential of hBMSCs were examined quantitatively by PrestoBlue assay, Ki67 immunofluorescence assay, real-time PCR technology and ALP staining. For in vivo detection, the repaired femur were evaluated by histomorphology and double fluorescence labeling 3 months postoperation. Porous tantalum coating surfaces promoted hBMSCs adhesion, proliferation, osteogenesis activity and had better osseointegration and faster new bone formation rate than titanium coating control. Our observation suggested that the porous tantalum coatings had good biocompatibility and could enhance osseoinductivity in vitro and promote new bone formation in vivo. The porous tantalum coatings prepared by VPS is a promising strategy for bone regeneration.

  11. Porous tantalum coatings prepared by vacuum plasma spraying enhance bmscs osteogenic differentiation and bone regeneration in vitro and in vivo.

    Science.gov (United States)

    Tang, Ze; Xie, Youtao; Yang, Fei; Huang, Yan; Wang, Chuandong; Dai, Kerong; Zheng, Xuebin; Zhang, Xiaoling

    2013-01-01

    Tantalum, as a potential metallic implant biomaterial, is attracting more and more attention because of its excellent anticorrosion and biocompatibility. However, its significantly high elastic modulus and large mechanical incompatibility with bone tissue make it unsuitable for load-bearing implants. In this study, porous tantalum coatings were first successfully fabricated on titanium substrates by vacuum plasma spraying (VPS), which would exert the excellent biocompatibility of tantalum and alleviate the elastic modulus of tantalum for bone tissue. We evaluated cytocompatibility and osteogenesis activity of the porous tantalum coatings using human bone marrow stromal cells (hBMSCs) and its ability to repair rabbit femur bone defects. The morphology and actin cytoskeletons of hBMSCs were observed via electron microscopy and confocal, and the cell viability, proliferation and osteogenic differentiation potential of hBMSCs were examined quantitatively by PrestoBlue assay, Ki67 immunofluorescence assay, real-time PCR technology and ALP staining. For in vivo detection, the repaired femur were evaluated by histomorphology and double fluorescence labeling 3 months postoperation. Porous tantalum coating surfaces promoted hBMSCs adhesion, proliferation, osteogenesis activity and had better osseointegration and faster new bone formation rate than titanium coating control. Our observation suggested that the porous tantalum coatings had good biocompatibility and could enhance osseoinductivity in vitro and promote new bone formation in vivo. The porous tantalum coatings prepared by VPS is a promising strategy for bone regeneration. PMID:23776648

  12. Statistic evaluation of cysteine and allyl alcohol as additives for Cu-Zn coatings from citrate baths

    Directory of Open Access Journals (Sweden)

    Julyana Ribeiro Garcia

    2013-04-01

    Full Text Available In the present work, cysteine and allyl alcohol were added to citrate baths as additives to Cu-Zn coatings on steel substrates. In order to verify the effects of the deposition parameters (current density, mechanical stirring speed, and additives on the coating composition, electrochemical behavior, morphology, and microstructure properties of Cu-Zn coatings, the electrodeposition of the alloy was carried out using an experimental composite design 2³, in which these parameters were considered the entry variables and the measured properties were the response variables. The confidence level was 95% and the results were shown as response surface diagrams. It was possible to verify that the current density affected the zinc content in the coating, while the coating produced from cysteine-contained bath presented the worse anticorrosive performance. In a general way, it was possible to observe that the studied parameters affected the morphology, grain size, and the electrochemical behavior of these coatings, although only a few response variables were statistically influenced by them.

  13. Statistic evaluation of cysteine and allyl alcohol as additives for Cu-Zn coatings from citrate baths

    Directory of Open Access Journals (Sweden)

    Julyana Ribeiro Garcia

    2012-01-01

    Full Text Available In the present work, cysteine and allyl alcohol were added to citrate baths as additives to Cu-Zn coatings on steel substrates. In order to verify the effects of the deposition parameters (current density, mechanical stirring speed, and additives on the coating composition, electrochemical behavior, morphology, and microstructure properties of Cu-Zn coatings, the electrodeposition of the alloy was carried out using an experimental composite design 2³, in which these parameters were considered the entry variables and the measured properties were the response variables. The confidence level was 95% and the results were shown as response surface diagrams. It was possible to verify that the current density affected the zinc content in the coating, while the coating produced from cysteine-contained bath presented the worse anticorrosive performance. In a general way, it was possible to observe that the studied parameters affected the morphology, grain size, and the electrochemical behavior of these coatings, although only a few response variables were statistically influenced by them.

  14. Corrosion protection of the reinforcing steels in chloride-laden concrete environment through epoxy/polyaniline–camphorsulfonate nanocomposite coating

    International Nuclear Information System (INIS)

    Highlights: • Epoxy/polyaniline–camphorsulfonate nanocomposite coating well protects steel rebar. • Coating performance is evaluated by impedance measurements up to 1 year. • Ultimate bond strength between the coated rebars and concrete is measured. • Self-compacting concrete shows better anticorrosive property compared to normal one. - Abstract: In this study, an epoxy/polyaniline–camphorsulfonate nanocomposite (epoxy/PANI–CSA) is employed to protect reinforcing steels in chloride-laden concrete environment. The synthesized nanocomposite was characterized using Fourier transform infrared spectroscopy and transmission electron microscopy. Bare, epoxy-coated and epoxy/PANI–CSA nanocomposite-coated steel rebars were embedded in normal and self-compacting concretes. To evaluate their corrosion behaviors, open circuit potential and impedance measurements were performed for the duration of 1 year. Ultimate bond strength of concrete with the reinforcement bars were measured in corroded and uncorroded conditions. It was found that epoxy/PANI–CSA coating provides good corrosion resistance and durable bond strength with concrete for steel rebars

  15. A Robust Epoxy Resins @ Stearic Acid-Mg(OH)2 Micronanosheet Superhydrophobic Omnipotent Protective Coating for Real-Life Applications.

    Science.gov (United States)

    Si, Yifan; Guo, Zhiguang; Liu, Weimin

    2016-06-29

    Superhydrophobic coating has extremely high application value and practicability. However, some difficult problems such as weak mechanical strength, the need for expensive toxic reagents, and a complex preparation process are all hard to avoid, and these problems have impeded the superhydrophobic coating's real-life application for a long time. Here, we demonstrate one kind of omnipotent epoxy resins @ stearic acid-Mg(OH)2 superhydrophobic coating via a simple antideposition route and one-step superhydrophobization process. The whole preparation process is facile, and expensive toxic reagents needed. This omnipotent coating can be applied on any solid substrate with great waterproof ability, excellent mechanical stability, and chemical durability, which can be stored in a realistic environment for more than 1 month. More significantly, this superhydrophobic coating also has four protective abilities, antifouling, anticorrosion, anti-icing, and flame-retardancy, to cope with a variety of possible extreme natural environments. Therefore, this omnipotent epoxy resins @ stearic acid-Mg(OH)2 superhydrophobic coating not only satisfies real-life need but also has great application potential in many respects. PMID:27265834

  16. Microstructure, corrosion properties and bio-compatibility of calcium zinc phosphate coating on pure iron for biomedical application.

    Science.gov (United States)

    Chen, Haiyan; Zhang, Erlin; Yang, Ke

    2014-01-01

    In order to improve the biocompatibility and the corrosion resistance in the initial stage of implantation, a phosphate (CaZn2(PO4)2·2H2O) coating was obtained on the surface of pure iron by a chemical reaction method. The anti-corrosion property, the blood compatibility and the cell toxicity of the coated pure iron specimens were investigated. The coating was composed of some fine phosphate crystals and the surface of coating was flat and dense enough. The electrochemical data indicated that the corrosion resistance of the coated pure iron was improved with the increase of phosphating time. When the specimen was phosphated for 30min, the corrosion resistance (Rp) increased to 8006 Ω. Compared with that of the naked pure iron, the anti-hemolysis property and cell compatibility of the coated specimen was improved significantly, while the anti-coagulant property became slightly worse due to the existence of element calcium. It was thought that phosphating treatment might be an effective method to improve the biocompatibility of pure iron for biomedical application. PMID:24268250

  17. Study on cerium-doped nano-TiO2 coatings for corrosion protection of 316 L stainless steel

    Science.gov (United States)

    Li, Suning; Wang, Qian; Chen, Tao; Zhou, Zhihua; Wang, Ying; Fu, Jiajun

    2012-04-01

    Many methods have been reported on improving the photogenerated cathodic protection of nano-TiO2 coatings for metals. In this work, nano-TiO2 coatings doped with cerium nitrate have been developed by sol-gel method for corrosion protection of 316 L stainless steel. Surface morphology, structure, and properties of the prepared coatings were investigated by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy. The corrosion protection performance of the prepared coatings was evaluated in 3 wt% NaCl solution by using electrochemical techniques in the presence and absence of simulated sunlight illumination. The results indicated that the 1.2% Ce-TiO2 coating with three layers exhibited an excellent photogenerated cathodic protection under illumination attributed to the higher separation efficiency of electron-hole pairs and higher photoelectric conversion efficiency. The results also showed that after doping with an appropriate concentration of cerium nitrate, the anti-corrosion performance of the TiO2 coating was improved even without irradiation due to the self-healing property of cerium ions.

  18. Synthesis and properties of electrodeposited Ni–B–CeO2 composite coatings

    International Nuclear Information System (INIS)

    Highlights: • Alteration of metallic luster, chemical composition and crystal structure. • Remarkable improvement in mechanical properties. • A decent improvement in corrosion behavior. - Abstract: Ni–B coatings are extremely hard and wear resistant with decent anticorrosion properties which make them suitable for automotive, aerospace, petrochemical, plastic, optics, nuclear, electronics, computer, textile, paper, food and printing industries. However, further improvement in properties is essential to address more challenging requirements and new developments. In the present study, Ni–B and novel Ni–B–CeO2 composite coatings were electrodeposited (ED) on mild steel substrates using dimethylamine borane (DMAB) as a reducing agent. A comparison of properties of Ni–B and Ni–B–CeO2 coatings is presented to elucidate the useful role of CeO2 addition. The structural analyses indicate that Ni–B coatings are amorphous in their as deposited state. However, addition of CeO2 into Ni–B matrix considerably improves the crystallinity of the deposit. The surface morphology study reveals the formation of uniform, dense and fine-grained deposit in both Ni–B and Ni–B–CeO2 composite coatings. However, Ni–B–CeO2 composite coatings exhibit high surface roughness. The nano mechanical properties show that the addition of CeO2 particles into Ni–B matrix results in remarkable improvement in mechanical properties (hardness and modulus of elasticity) which may be attributed to dispersion hardening of Ni–B matrix by CeO2 particles. The electrochemical polarization tests confirm that the addition of CeO2 improves the corrosion resistance of Ni–B coatings. This improvement in corrosion behavior may be ascribed to the reduction in active area of Ni–B coatings by the presence of inactive CeO2 particles into Ni–B matrix

  19. The Anti-Corrosion Coating for the Port Machinery%港口机械设备的防腐蚀涂装

    Institute of Scientific and Technical Information of China (English)

    涂枫; 王小春

    2010-01-01

    防腐蚀是港口机械长期使用中的重要课题.介绍了目前通用的港口机械的涂料的品种,应用于海洋重防腐环境下的港口机械涂层体系的设计方案.全面讲解了通用的港口机械涂装的施工步骤和施工方法.

  20. Development of Light Waterborne Epoxy Antistatic Anticorrosive Coatings%浅色水性环氧导静电防腐涂料的研制

    Institute of Scientific and Technical Information of China (English)

    刘成楼; 隗功祥

    2011-01-01

    研制的水性环氧导静电防腐涂料为双组分涂料,甲组分由水性胺加成物固化剂、导电填料、防锈颜填料及助剂组成;乙组分由环氧树脂E51或OER-95、活性稀释剂、掺杂聚苯胺及偶联剂组成,按环氧/胺当量比为1.1∶1配漆,涂层具有优异的导静电性和防腐蚀性能.

  1. Elemental depth analysis of corroded paint-coated steel by confocal micro-XRF method

    International Nuclear Information System (INIS)

    A confocal micro-XRF method combined with two individual polycapillary lenses was applied to steel sheets coated with anti-corrosive paint in order to nondestructively observe 3D elemental distribution of paint steels and corroded paint-coated steels. Nondestructive depth analysis and 3D elemental mapping of the painted steel sheets were demonstrated under the confocal XRF configuration. Three different painted steel sheets were prepared by cation electrodeposition coating for automotive onto flat steel sheets modified with a zinc phosphate conversion coating. These painted sheets were then caused to corrode by means of accelerated exposure to a salt bath (5 mass% NaCl) at 55°C for 240 hours. Depth elemental profiles of Ti, Zn, and Fe obtained by confocal micro-XRF measurements were in excellent agreement with that of the prepared sample. Elemental depth profiles and maps of the corroded painted sheets showed some blisters caused by crevice corrosion, which started from the site of a scratch. The distributions of Ti and Fe were approximately homogeneous in both the paint layer and the steel substrate, while the distributions of Zn, Mn, Ca, and Cl were heterogeneous. (author)

  2. Fabrication and performance of TiN/TiAlN nanometer modulated coatings

    Energy Technology Data Exchange (ETDEWEB)

    Liang Changlin [Key Laboratory of Beam Technology and Material Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Department of Physics, Tsinghua University, Beijing 100084 (China); Cheng Guoan, E-mail: gacheng@bnu.edu.cn [Key Laboratory of Beam Technology and Material Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Zheng Ruiting; Liu Huaping [Key Laboratory of Beam Technology and Material Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China)

    2011-11-01

    TiN/TiAlN multilayered coatings with bilayer periods ({lambda}{sub BD}) ranging from 6 to 30 nm were prepared on TC4 alloy and Si (100) wafer substrates by magnetic filtered pulsed vacuum cathodic arc plasma technique. The analyses with scanning electron microscope (SEM), X-ray diffraction (XRD), X-ray energy dispersive spectroscope (EDS) and X-ray photoelectron spectroscope (XPS) with Ar + sputtering indicated that the as-deposited coatings had nanometer modulated structure, TiN and TiAlN with (111) preferred orientation were the main compounds and the average atoms ratio of N:(Ti + Al) was about 1.24-1.29. Scratch test showed that the coatings were fairly adherent to TC4 substrates, and the maximal critical load was about 57 N. The highest nano-hardness and modulus about 28 GPa and 283 GPa, respectively, were obtained for the multilayer with {lambda}{sub BD} = 12 nm, examined with nano-indentation method. The electrochemical corrosion test showed that the coatings improved the TC4 alloy's property of anti-corrosion effectively, especially with {lambda}{sub BD} = 20 nm.

  3. A polyaniline based intrinsically conducting coating for corrosion protection of structural steels.

    Science.gov (United States)

    Pan, Tongyan; Wang, Zhaoyang

    2013-11-01

    Among the various corrosion protection strategies for structural steels, coating techniques provide the most cost-effective protection and have been used as the primary mode of corrosion protection. Existing coating techniques however have been used mainly for their barrier capability and therefore all have a limited service life due to oxidation aging, electrolytic degradation, or various inadvertent defects and flaws occurred in and after coating applications. This work investigated the anti-corrosion potential of a π-conjugated polymer-polyaniline (PANi), which was doped into an intrinsically conducting polymer and then included in a two-layer coating system as a primer layer. To achieve a long service life, the primer layer was made by mixing the conductive PANi in a waterborne poly-vinyl butyral solution to provide strong adhesion to steel surface, and then topcoated with a layer of elastomer-modified polyethylene to obtain extra mechanical and barrier protections. Two ASTM standard tests were conducted to evaluate the corrosion durability and tensile adhesion of the two-layer system, in which the system demonstrated superior performance. The Scanning Kelvin Probe Force Microscopy (SKPFM) was used to provide the microscopic evidences for the outstanding performance. PMID:24000080

  4. Facile approach in the development of icephobic hierarchically textured coatings as corrosion barrier

    Science.gov (United States)

    Momen, G.; Farzaneh, M.

    2014-04-01

    An anti-corrosion superhydrophobic film with water contact angle greater than 160° on aluminum alloy 6061 substrate was fabricated simply through the spin-coating method applied to Al2O3 nanoparticles doped in silicone rubber solution. The as-obtained sample was characterized by scanning electron microscopy (SEM) and water contact angle/surface energy measurement. The corrosion behaviour of such coating in the NaCl solutions was investigated using the potentiodynamic polarization. The results show that the corrosion resistance of the developed superhydrophobic surface is improved greatly due to the composite wetting states or interfaces with numerous air pockets between its surface and the NaCl solution. This superhydrophobic coating could serve as an effective barrier against aggressive medium. Ice adhesion strength of the as-prepared superhydrophobic coating was also evaluated by measuring its ice adhesion force which was found to have reduced by 4.8 times compared to that of aluminum substrate as reference test.

  5. Study on Corrosion of the Foam Glass Anti-corrosion Lining%泡沫玻璃砖防腐内衬腐蚀研究

    Institute of Scientific and Technical Information of China (English)

    黎优霞; 冀运东

    2015-01-01

    Etching solution leaked from the thermal power plant wet chimney, which adopted domestic foam glass anti-corrosion lining and worked for a period of time. The performance of the foam glass anti-corrosion lining of it was studied in this paper. The properties of the foam glasses and plaster picking from the chimney lining were characterized by EDS and FT-IR. The results showed that the alkali metals (including Fe, K, Al, Na, Mg and so on) in the domestic foam glasses reacted with the acid corrosive media of the wet gas, which gave rise to the destruction of the closed pore structure and crisp cracking of the bricks; meanwhile, pendant groups on the polysiloxane matrix shed and Si-O-Si rigid structure increased in the main chain, which result in the loss of elasticity and adhesion of the plaster, then the foam dlass anti-corrosion lining fell off.%采用国产泡沫玻璃砖防腐内衬的火电厂湿烟囱,运行一段时间后,出现严重的渗透腐蚀现象。本文以湿烟囱排烟筒上脱落的泡沫玻璃砖为实验对象,利用EDS和FT-IR分别研究了国产泡沫玻璃砖和有机硅防腐胶泥的腐蚀状况及原理。结果表明,国产泡沫玻璃砖中含有Fe、K、Al、Na、Mg等碱金属,遇酸反应,导致砖体密闭孔隙结构破坏,酥化开裂,失去防腐作用;聚硅氧烷基体的侧基脱落,主链中Si-O-Si刚性结构增多,胶泥失去弹性和粘接性,导致防腐内衬整体脱落。

  6. “SMART” protective ability of water based epoxy coatings loaded with CaCO3 microbeads impregnated with corrosion inhibitors applied on AA2024 substrates

    International Nuclear Information System (INIS)

    Highlights: ► CaCO3 microbeads were used as pH-sensitive reservoirs for corrosion inhibitors. ► The barrier properties of the coating with CaCO3/inhibitors were improved. ► The corrosion inhibitors were released as a result of dissolution of pH sensitive CaCO3. ► LEIS demonstrated the local corrosion inhibition provided by the CaCO3/Ce over localised defect formed in the coating. - Abstract: Corrosion protection of aluminium alloys often relies on the application of a coating on the metallic surface. The coating normally combines a barrier effect that restricts the ingress of corrosive species, with an inhibitive role induced by corrosion inhibitor pigments added to the coating formulation. However, the direct addition of corrosion inhibitors to the coating can cause some detrimental interactions between components, as well as formation of preferential electrolyte pathways, compromising the barrier properties. Moreover, electrolyte uptake and ageing may result in leaching of those corrosion inhibitors. In order to extend the corrosion inhibition ability of organic coatings one possible solution is to store the inhibitors inside nano or microreservoirs compatible with the coating matrix and able to sense the local changes induced by the corrosion process. This strategy has led to the development of a new generation of “smart” coatings for anti-corrosion purposes. The aim of this work is to study the anti-corrosion properties of water-based epoxy coatings loaded with pH sensitive particles, acting as feedback active containers for corrosion inhibitors and applied on the aluminium alloy AA2024-T3. For this purpose micron size calcium carbonate beads were modified with different corrosion inhibitors: cerium nitrate, salicylaldoxime and 2,5-dimercapto-1,3,4-thiadiazolate. These particles act as pH sensitive reservoirs because they dissolve at acidic pH, releasing the corrosion inhibitor, which then suppresses the corrosion activity of the bare metal

  7. Highly flexible transparent self-healing composite based on electrospun core-shell nanofibers produced by coaxial electrospinning for anti-corrosion and electrical insulation

    Science.gov (United States)

    An, Seongpil; Liou, Minho; Song, Kyo Yong; Jo, Hong Seok; Lee, Min Wook; Al-Deyab, Salem S.; Yarin, Alexander L.; Yoon, Sam S.

    2015-10-01

    Coaxial electrospinning was used to fabricate two types of core-shell fibers: the first type with liquid resin monomer in the core and polyacrylonitrile in the shell, and the second type with liquid curing agent in the core and polyacrylonitrile in the shell. These two types of core-shell fibers were mutually entangled and embedded into two flexible transparent matrices thus forming transparent flexible self-healing composite materials. Such materials could be formed before only using emulsion electrospinning, rather than coaxial electrospinning. The self-healing properties of such materials are associated with release of healing agents (resin monomer and cure) from nanofiber cores in damaged locations with the subsequent polymerization reaction filing the micro-crack with polydimethylsiloxane. Transparency of these materials is measured and the anti-corrosive protection provided by them is demonstrated in electrochemical experiments.

  8. EPOXY VINYL ESTER ANTICORROSIVE FLOOR AND ITS MANUFACTURE PROCESS%环氧乙烯基防腐地坪及制备工艺

    Institute of Scientific and Technical Information of China (English)

    葛平; 卞忠义

    2001-01-01

    介绍了Atlac环氧乙烯基玻璃钢防腐地坪和Atlac环氧乙烯基树脂混凝土防腐地坪的制作工艺,也介绍了用于防腐地坪的Atlac系列环氧乙烯基树脂的性能、玻璃纤维的选择及其它辅助材料的指标、配比等。%The Atlac epoxy vinyl ester FRP and concrete anticorrosive floor.Their composition and manufacture process,the properties of a series of Atlac epoxy vinyl ester resin,selection of glass fibre and performance date of other assistant materials were introduced in this paper.

  9. Environmental Coating Layer for the Metal-Ceramic Hybrid Fuel Cladding Tubes

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Yangil; Kim, Sunhan; Park, Dongjun; Kim, Hyungil; Park, Jeongyong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-05-15

    The dissolution is much faster as the composition is off the stoichiometry. Since the SiC pre ceramic polymer impregnation results in excess oxygen or carbon in the composite matrix, the outer environmental barrier is indispensable to prevent the expected corrosion. Several candidates were considered as a surface coating material. Oxides such as ZrO{sub 2}, ZrO{sub 2}.Y{sub 2}O{sub 3}, SiO{sub 2}, Cr{sub 2}O{sub 3}, and Ta{sub 2}O{sub 5} are very stable in water. Also, the safety of fuel cladding against off-normal accidents could be increased, since the oxides can endure very high temperature. ZrO{sub 2} in a nuclear environment has been studied a lot since it is naturally formed on conventional fuel cladding tubes. In the case of SiO{sub 2}, the transformation of the crystal phase during irradiation was reported; however, their effect on the corrosion resistance was not investigated. Cr{sub 2}O{sub 3} and Ta{sub 2}O{sub 5} are quite good as a protective anti-corrosion layer, but inappropriate in terms of the neutron cross-section. A sol-gel based coating method and a synthesis of the precursor materials are being developed for the surface coating. Surface coating of of ZrO{sub 2} and ZrO{sub 2}.Y{sub 2}O{sub 3} on SiC was performed using a sol-gel dip coating method. Although the coated layer was impractical as a barrier of SiC dissolution, the preliminary test of coating materials can suggest the direction to further research.

  10. Study of thermal stability for tertiary pyridine ion exchange resin and anti-corrosion property of structural material toward eluents used in the advanced ORIENT cycle process

    International Nuclear Information System (INIS)

    A multi-functional separation process is proposed as one of the technologies for implementing the Adv.-ORIENT (Advanced Optimization by Recycling Instructive ElemeNTs) Cycle concept. The tertiary pyridine-type anion exchange resin (TPR) embedded in silica beads (silica-supported TPR) was demonstrated suitable for the separation process of actinides from spent fuel. In this process, hydrochloric acid (HCl) and a mixture of nitric acid (HNO3) and methanol (MeOH) are used as eluents. In order to apply this process to an engineering plant scale, two important issues must be evaluated to prove the system suitability. One is an environmental aspect represented by the use of HCl solution which is corrosive to many materials. The other is clarification of the reactive safety of silica-supported TPR and the HNO3-MeOH solvent mixture. Four types of metals, Ta, Zr, Nb, and Hastelloy-B (28%Mo-Ni) were selected as candidate materials which are anti-corrosive toward HCl. Corrosion experiments were conducted in HCl type simulated high level liquid waste (SHLLW) solution at room temperature for a maximum 720 h and at 90 deg C for 336 h. Ta showed an all-round anti-corrosion property in HCl type SHLLW solution, and Hastelloy-B was only acceptable at room temperature. Thermal analysis by differential scanning calorimetry was done to investigate the thermal stability of silica-supported TPR-NO3/MeOH/HNO3 mixtures. Heating experiment results on a gram scale were also obtained and evaluated to determine the conditions necessary to avoid runaway reactions. As a result, it was confirmed that a vigorous exothermic reaction can be avoided by controlled decrease of temperature. (author)

  11. POLYTETRAFLUOROETHYLENE-RICH POLYPHENLENESULFIDE BLEND TOP COATINGS FOR MITIGATING CORROSION OF CARBON STEEL IN 300 DEGREE CELCIUS BRINE.

    Energy Technology Data Exchange (ETDEWEB)

    SUGAMA, T.; JUNG, D.

    2006-06-01

    We evaluated usefulness of a coating system consisting of an underlying polyphenylenesulfide (PPS) layer and top polytetrafluoroethylene (PTFE)-blended PPS layer as low friction, water repellent, anti-corrosion barrier film for carbon steel steam separators in geothermal power plants. The experiments were designed to obtain information on kinetic coefficient of friction, surface free energy, hydrothermal oxidation, alteration of molecular structure, thermal stability, and corrosion protection of the coating after immersing the coated carbon steel coupons for up to 35 days in CO{sub 2}-laden brine at 300 C. The superficial layer of the assembled coating was occupied by PTFE self-segregated from PPS during the melt-flowing process of this blend polymer; it conferred an outstanding slipperiness and water repellent properties because of its low friction and surface free energy. However, PTFE underwent hydrothermal oxidation in hot brine, transforming its molecular structure into an alkylated polyfluorocarboxylate salt complex linked to Na. Although such molecular transformation increased the friction and surface free energy, and also impaired the thermal stability of PTFE, the top PTFE-rich PPS layer significantly contributed to preventing the permeation of moisture and corrosive electrolytes through the coating film, so mitigating the corrosion of carbon steel.

  12. Properties of Ni/Nano-TiO2 Composite Coatings Prepared by Direct and Pulse Current Electroplating

    Science.gov (United States)

    Yılmaz, Gülesin; Hapçı, Gökçe; Orhan, Gökhan

    2015-02-01

    Pure nickel and nickel matrix composite coatings containing nano-TiO2 particles were produced under both direct and pulse current conditions from an additive-free nickel Watts' type bath. The surface morphology, crystal size, crystallographic orientation, and microhardness of nickel matrix and the amount of embedded nano-TiO2 particles in the composite coatings were investigated. The corrosion performance of the coatings was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy methods. The TiO2 particles embedded in the nickel matrix exerted strong influence on the texture of the growing nickel layer, changing its texture under both direct and pulse current conditions. The textural perfection of the deposits revealed that the presence of TiO2 particles led to the deteriorating of [100] preferred orientation. Under direct current conditions, the composite coating exhibited clearly [211] fiber orientation, while pulse current working exhibited a mixed crystal orientation through [100] and [211] axes. It is concluded that in the presence of TiO2 nanoparticles, the adsorption-desorption phenomena occurring on the metal surface are altered. The experimental results show that composite electrodeposits prepared under pulse plating conditions exhibited higher incorporation percentages than those obtained under direct plating conditions, at particularly 10 Hz and low duty cycles. The results revealed that pulse-plated Ni/TiO2 nanocomposite coating provided excellent anti-corrosion performance and presented higher microhardness.

  13. Influence of hydroxyapatite coating thickness and powder particle size on corrosion performance of MA8M magnesium alloy

    International Nuclear Information System (INIS)

    Graphical abstract: The corrosion resistance of magnesium alloys is the primary concern in biomedical applications. Micron and nano-scale hydroxyapatite (HA) was coated successfully on MA8M magnesium alloy substrates by using a sol–gel deposition. In this study, the effects of coating thicknesses and HA powder particle sizes on the adhesion strength and corrosion behavior were investigated. Potentiodynamic polarization tests were performed in a Ringer solution. The coatings before and after corrosion tests were characterized by adhesion tests, scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The micro-scale-HA coated Mg substrates were more corrosion resistant than the nano-scale-HA coatings. The anodic activity of the micro-scale-HA coatings increased with increased coating thickness and the corrosion resistance of Mg substrates decreased. Corrosion susceptibilities of the nano-scale-HA coated samples were affected inversely. The coated film provided good barrier characteristics and achieved good corrosion protection for Mg substrates when compared to substrates without coatings. For micro-scale-HA coatings, anodic and cathodic activities were more intense for thicker films. When HA coatings are compared to nano-scale HA coatings, the micro-scale-HA coatings produced better current density values. Overall, as shown in Fig. 1, the best corrosion behavior of the Mg alloys was achieved using micro-scale HA powders at 30 μm coating thickness. - Highlights: • Nano and micro-scale-HA coatings provided good anti-corrosion performance compared to the uncoated ones. • The micro-scale-HA coated Mg substrates were more corrosion resistant than the nano-scale-HA coatings. • The best corrosion behavior was achieved for the micro-scale HA powders at 30 μm coating thickness. • Anodic activity decrease and cathodic activity increase with increasing film thickness. - Abstract: To improve the corrosion resistance of MA8M magnesium alloy, sol

  14. Influence of hydroxyapatite coating thickness and powder particle size on corrosion performance of MA8M magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Sonmez, S. [Hakkari University, Dept. of Biomedical Eng., 30000 Hakkari (Turkey); Aksakal, B., E-mail: baksakal@yildiz.edu.tr [Yildiz Technical University, Chemical Metallurgy Faculty, Dept. of Metall and Mater Eng., Istanbul (Turkey); Dikici, B. [Yuzuncu Yil University, Dept. of Mechanical Eng., 65080 Van (Turkey)

    2014-05-01

    Graphical abstract: The corrosion resistance of magnesium alloys is the primary concern in biomedical applications. Micron and nano-scale hydroxyapatite (HA) was coated successfully on MA8M magnesium alloy substrates by using a sol–gel deposition. In this study, the effects of coating thicknesses and HA powder particle sizes on the adhesion strength and corrosion behavior were investigated. Potentiodynamic polarization tests were performed in a Ringer solution. The coatings before and after corrosion tests were characterized by adhesion tests, scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The micro-scale-HA coated Mg substrates were more corrosion resistant than the nano-scale-HA coatings. The anodic activity of the micro-scale-HA coatings increased with increased coating thickness and the corrosion resistance of Mg substrates decreased. Corrosion susceptibilities of the nano-scale-HA coated samples were affected inversely. The coated film provided good barrier characteristics and achieved good corrosion protection for Mg substrates when compared to substrates without coatings. For micro-scale-HA coatings, anodic and cathodic activities were more intense for thicker films. When HA coatings are compared to nano-scale HA coatings, the micro-scale-HA coatings produced better current density values. Overall, as shown in Fig. 1, the best corrosion behavior of the Mg alloys was achieved using micro-scale HA powders at 30 μm coating thickness. - Highlights: • Nano and micro-scale-HA coatings provided good anti-corrosion performance compared to the uncoated ones. • The micro-scale-HA coated Mg substrates were more corrosion resistant than the nano-scale-HA coatings. • The best corrosion behavior was achieved for the micro-scale HA powders at 30 μm coating thickness. • Anodic activity decrease and cathodic activity increase with increasing film thickness. - Abstract: To improve the corrosion resistance of MA8M magnesium alloy, sol

  15. Effect of surface modification of Cu with Ag by ball-milling on the corrosion resistance of low infrared emissivity coating

    Energy Technology Data Exchange (ETDEWEB)

    Yan Xiaoxing, E-mail: yanxiaoxing@nuaa.edu.c [College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Jiangjun Street, Nanjing 211100 (China); Xu Guoyue [College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Jiangjun Street, Nanjing 211100 (China)

    2010-01-25

    The corrosion resistance of low infrared emissivity copper/polyurethane (Cu/PU) coating was markedly improved by surface modification of Cu with silver (Ag) using a ball-milling method. For the purpose of clarifying the effect of the surface modification, the phase and morphology of as-prepared products were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and the corrosion behavior was investigated with potentiodynamic polarization and electrochemical impedance spectra (EIS). As a result, it was found that Ag was homogeneously distributed in Cu and the encapsulation of oil layer on the surface of Ag-Cu composite powders was formed after ball-milling, therefore, compatibility with organic phase was improved, which often keeps the low infrared emissivity and enhances the anti-corrosion performance of the coating.

  16. Effect of surface modification of Cu with Ag by ball-milling on the corrosion resistance of low infrared emissivity coating

    International Nuclear Information System (INIS)

    The corrosion resistance of low infrared emissivity copper/polyurethane (Cu/PU) coating was markedly improved by surface modification of Cu with silver (Ag) using a ball-milling method. For the purpose of clarifying the effect of the surface modification, the phase and morphology of as-prepared products were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and the corrosion behavior was investigated with potentiodynamic polarization and electrochemical impedance spectra (EIS). As a result, it was found that Ag was homogeneously distributed in Cu and the encapsulation of oil layer on the surface of Ag-Cu composite powders was formed after ball-milling, therefore, compatibility with organic phase was improved, which often keeps the low infrared emissivity and enhances the anti-corrosion performance of the coating.

  17. Theoretical basis of Al-Si coat crystallization on gray and nodular cast iron and making the layered items using it

    Directory of Open Access Journals (Sweden)

    S. Pietrowski

    2011-12-01

    Full Text Available Purpose: The aim of this study was to present studies of crystallization and the construction of the coat consisting of Al-Si alloys, also with alloy additives: Ni, Cu and Mg, deposited on gray and nodular cast iron, and the connection through this coat the layered item. On this basis, a model of creating a coat and layered item was developed.Design/methodology/approach: Studies of coats and layered products were carried out on scanning electron and optical microscopes. The chemical microanalysis and diffraction of backward scattered atoms in the characteristic areas of the coat and substrate material was made.Findings: : In this paper the influence of the most important technological factors on the thickness and phase construction of the silumin coat and connection quality in the layered item was presented.Research limitations/implications: Currently, research of dip application of coats made of silumins containing: Cu, Ni, Mg, Cr, Mo, W and V on non-alloy and alloy steels and the manufacture of layered items to their use are conducted.Practical implications: Dip coats are used as protective coats or intermediate coat of layered item. The paper presents an example of the implementation for the manufacture of the layered items low-alloyed gray cast iron-silumin coat-silumin reciprocating compressor body for room air conditioning.Originality/value: Originality of the paper consists in elaborating of the theoretical model of forming the diffusion layer made of Al-Si-M silumin on iron alloys. Theoretical basis of layers production were elaborated too. They are significant for collar fillings production in high-pressure combustion engines pistons, as anticorrosive layers and for layered items production.

  18. New Thiosemicarbazone and Talinum triangulare Vegetal Extract Formulations with Potential Anti-corrosion Activity [Novas Formulações de Tiossemicarbazonas e Extrato Vegetal de Talinum triangulare com Potencial Atividade Anticorrosão

    Directory of Open Access Journals (Sweden)

    Mariana A . de Albuquerque

    2013-06-01

    Full Text Available Corrosion is a process arising out of a chemical action of the environment on a particular material, causing its deterioration. It may occur in metals, concrete, organic polymers, and others. A promising alternative to prevent corrosion is the use of organic inhibitors. The search for new agents or formulations that enable the diminishing of corrosion effects is evidently necessary; therefore, this work evaluated 3 new formulations which contained thiosemicarbazones 4-hydroxy,3-methoxybenzaldehyde-thiosemicarbazone, 4-ethoxybenzaldehyde-thiosemicarbazone and 4-hydroxybenzaldehyde-thiosemicarbazone with the crude extract of Talinum triangulareleaves in ethyl acetate, aiming at the Fe2+ ion chelation for an anticorrosive action. UV-Vis spectroscopy was used to evaluate the formation of Fe2+ ion complexes; also, to determine the respective coordination numbers with the thiosemicarbazones. Results indicated the increase of the thiosemicarbazone anticorrosive action, which had been evaluated by molecular modeling and potentiodynamic polarization, when there were crude extract of T. triangulareleaves in the formulation.

  19. 铝合金大气腐蚀行为及其防腐措施研究进展%Research Progress in Atmospheric Corrosion Behavior and Anticorrosion Measures of Aluminum Alloy

    Institute of Scientific and Technical Information of China (English)

    王彬; 苏艳

    2012-01-01

    综述了铝合金的大气腐蚀机理和大气主要环境因素对铝合金的大气腐蚀的影响.重点介绍了近年来所采用的对环境无害的铝合金无铬防腐蚀处理方法(激光熔覆法、溶胶-凝胶法、聚合物防腐蚀膜等)及其发展前景.%The atmospheric corrosion mechanism and the effect of principal pollutants of atmosphere on corrosion of aluminum alloy were summarized. The emphasis was on current used Cr-free and environment-friendly anticorrosive protection systems (such as laser cladding method, sol-gel method and anticorrosive polymer film) for aluminum alloy and its development prospect.

  20. Corrosion Resistance of Coating with Fe-based Metallic Glass Powders Fabricated by Laser Spraying

    Directory of Open Access Journals (Sweden)

    Wang Yingjie

    2013-01-01

    Full Text Available In order to improve their wearing resistance, some reinforced particles such as TiN and WC were usually inserted into Fe-based Metallic Glassy Coatings (Fe-MGC. In this study, a new Fe-MGC was fabricated with the powder mixtures of Fe-based metallic glass, NiCr alloy and WC particle by laser spraying. The corrosion resistance of Fe-MGC was investigated by potentiodynamic polarization tests in 1 M HCl, NaCl, H2SO4 and NaOH solutions, respectively. The microstructures were detected by X-ray diffraction and scanning electron microscope. The Fe-MGC of Fe68.5 C7.1 Si3.3 B5.5 P8.7 Cr2.3 Mo2.5 Al2.0+NiCr+tungsten carbon exhibits low corrosion current density of 10.6 and 3.3 μA, high corrosion potential of 326.4 and 367.5 mV in HCl and NaCl solutions, respectively. The results indicate Fe-MGC presents low porosity and high microhardness implying superior wearing properties, moreover, exhibits excellent corrosion resistance and no inferior than that of full amorphous coatings in various solutions. The excellent corrosion resistance and wearing properties demonstrates that Fe-based metallic glassy matrix powder is a viable engineering material as practical anti-corrosion and anti-wear coating applications.

  1. Effects of Copper and Titanium Elements on the Coating's Properties of Hot-Dipping-Aluminum Steel

    Institute of Scientific and Technical Information of China (English)

    JIA Wei-ping; MA Yun-long; HU Lin; KE Wei

    2004-01-01

    The steel plates for testing obtained a clean and fresh surface after degreasing by alkali and acidity and to be protested from reoxidation by being dipped into liquid wax. The results after hot dipping experiments in lab. showed that a complete aluminized coat with a good property could be obtained under a condition of hot-dipping temperature at about 730 ℃, hot -dipping time at about 2 minutes. It was found that the transition layer was mainly composed of Fe2 Al5 intermetallic compound by SEM (Scanning Electronic Microscope) observation. Effects of elements copper and titanium in aluminum coating on adherence quality, corrosion resistance performance and thickness of the transition layer were investigated, the following results were drawn: The adherence quality is strongly enhancedby copper element and gives the best performance at the 2% mass percent content of copper, while it is almost indifferent with titanium content. The corrosion resistance property is enhanced by titanium and is deteriorated by copper, when the mass percent content of titaniumis 0.3% , the coating exhibits the best anti-corrosion performance. At present condition, both copper and titanium make transition layer thinner.

  2. Fabrication of color-controllable superhydrophobic copper compound coating with decoration performance

    Science.gov (United States)

    Tan, Cui; Li, Qing; Cai, Peng; Yang, Na; Xi, Zhongxian

    2015-02-01

    A facile and low-cost method for fabricating the color-controllable superhydrophobic coatings on copper was reported in this paper. By simply changing the electrolytic conditions, tunable color surfaces can be obtained. The fundamental cause of color variation should be attributed to the composition of resulting coatings. After modification with stearic acid, the contact angles (CA) of samples with three different colors are 156.8°, 160.0°, 162.8°, respectively, and slide angles (SA) are all nearly 1°. In addition, potentiodynamic polarization test, pH stability, atmospheric exposure test, antibacterial test, abrasion test and tape adhesion test were also performed from the viewpoint of the physical stability and chemical stability of superhydrophobic surfaces. Results indicate that the obtained surfaces be of excellent environmental adaptability, high anti-corrosion ability, and good mechanical property. Results reported here would be helpful for enlarging the application of superhydrophobic surface. Moreover, this method, chemical in situ growth of colored coating, is a new strategy for preparing color-tuned superhydrophobic surface and could be applied on other metal substrates.

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

    Science.gov (United States)

    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

  4. Study on cerium-doped nano-TiO2 coatings for corrosion protection of 316 L stainless steel.

    Science.gov (United States)

    Li, Suning; Wang, Qian; Chen, Tao; Zhou, Zhihua; Wang, Ying; Fu, Jiajun

    2012-01-01

    Many methods have been reported on improving the photogenerated cathodic protection of nano-TiO2 coatings for metals. In this work, nano-TiO2 coatings doped with cerium nitrate have been developed by sol-gel method for corrosion protection of 316 L stainless steel. Surface morphology, structure, and properties of the prepared coatings were investigated by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy. The corrosion protection performance of the prepared coatings was evaluated in 3 wt% NaCl solution by using electrochemical techniques in the presence and absence of simulated sunlight illumination. The results indicated that the 1.2% Ce-TiO2 coating with three layers exhibited an excellent photogenerated cathodic protection under illumination attributed to the higher separation efficiency of electron-hole pairs and higher photoelectric conversion efficiency. The results also showed that after doping with an appropriate concentration of cerium nitrate, the anti-corrosion performance of the TiO2 coating was improved even without irradiation due to the self-healing property of cerium ions. PMID:22515192

  5. CHARACTERIZATION AND PROCESSING OF SCALES FROM THE MECHANICAL DESCALING OF CARBON STEELS FOR RECYCLING AS COATING PIGMENTS

    Directory of Open Access Journals (Sweden)

    Anderson de Oliveira Fraga

    2014-10-01

    Full Text Available The large volume of solid wastes generated as scales in Steel Mills accounts to circa 1% to 2% of the total steel production and has led to studies aiming the recycling of scales, usually resulting in products of low added value. In this study, scales from the mechanical descaling of SAE 1045 steel were characterized by SEM and by quantitative X-Ray diffraction (Rietveld method, as well as by differential thermal analysis, aiming to develop its pretreatment for the further use as lamellar pigments in anticorrosive coatings of high added value. Aspect ratios between 1:50 and 1:100 were obtained by the processing of scales, which allows the replacement of other micaceous iron oxides.

  6. Graphene Coatings

    DEFF Research Database (Denmark)

    Stoot, Adam Carsten; Camilli, Luca; Bøggild, Peter

    2014-01-01

    Owing to its remarkable electrical and mechanical properties, graphene has been attracting tremendous interest in materials science. In particular, its chemical stability and impermeability make it a promising protective membrane. However, recent investigations reveal that single layer graphene...... cannot be used as a barrier in the long run, due to galvanic corrosion phenomena arising when oxygen or water penetrate through graphene cracks or domain boundaries. Here, we overcome this issue by using a multilayered (ML) graphene coating. Our lab- as well as industrial-scale tests demonstrate that ML...... graphene can effectively protect Ni in harsh environments, even after long term exposure. This is made possible by the presence of a high number of graphene layers, which can efficiently mask the cracks and domain boundaries defects found in individual layers of graphene. Our findings thus show...

  7. DN<100外镀锌内涂塑螺纹管件机械加工工艺%Mechanical processing technology for DN<100 outside surface coated galvanizing inside surface plastic-coating thread fittings

    Institute of Scientific and Technical Information of China (English)

    孙冰心

    2011-01-01

    针对市场上给水螺纹管件存在的问题,我们在外镀锌内涂塑可锻铸铁管件的塑粉涂料和机械加工工艺方面做了较大改进,较好地解决了小于DN100热镀锌内涂塑钢管的接口螺纹连接涂塑膜质量问题,保证了管件的防蚀和密封性能,使涂塑管路全程性能得到保证,整体管路和高层建筑同寿命,免维修.%For the shortcoming of thread fittings for water supply,we do great progress in plastic powder and mechanical processing technology for the malleable iron hot-dip galvanizing fittings ,the quality of plastic membrane was solved in thread connection fittings of the DN<100 outside surface coated galvanizing irside surface plastic-coating steel tube.Better anti-corrosion and seal performances of the fittings ensure the full performance of the coating pipe.The life of overall coating pipe are the same as the high-rise buildings and maintenance-free.

  8. Electrocurtain coating process for coating solar mirrors

    Science.gov (United States)

    Kabagambe, Benjamin; Boyd, Donald W.; Buchanan, Michael J.; Kelly, Patrick; Kutilek, Luke A.; McCamy, James W.; McPheron, Douglas A.; Orosz, Gary R.; Limbacher, Raymond D.

    2013-10-15

    An electrically conductive protective coating or film is provided over the surface of a reflective coating of a solar mirror by flowing or directing a cation containing liquid and an anion containing liquid onto the conductive surface. The cation and the anion containing liquids are spaced from, and preferably out of contact with one another on the surface of the reflective coating as an electric current is moved through the anion containing liquid, the conductive surface between the liquids and the cation containing liquid to coat the conductive surface with the electrically conductive coating.

  9. Synthesis of P(St-BA-MAA-SPAA) nano-latex and its application in high anti-corrisive coating

    Institute of Scientific and Technical Information of China (English)

    LIU Hai-feng; SHENG Ming-shuang; PAN Zhao-ji; QIU Da-jian; GUO Zhi-hua; GAN Fu-xing

    2008-01-01

    A novel zinc-rich pigment based on P(St-BA-MAA-SPAA) nano-latex was obtained, which is suitable for the use in hot alkali liquid medium. The nano-latex was synthesized by active emulsifier latex polymerization method with monomers of styrene(St), butylaerylate (BA), methylacrylic acid(MAA) in the presence of active emulsifier 3-sulfopropylaerylate(SPAA). The synthesis condition and properties of the latex were investigated. And the anti-corrosive property of the resultant zinc-rich coating was studied. The results show that the nano-latex is self-stabilized and has a narrow particle diameter distribution, the average diameter of the latex particles is 71 nm. Zinc powders can be evenly dispersed in the nano-latex, which indicates that the P(St-BA-MAA-SPAA)nano latex can be used as the binder of zinc-rich coating. The resultant zinc-rich coating is able to resist the invasion of hot alkali solution(the temperature is 95 ℃ and the pH value is 14) for 480 h and the exposure time in salt spray is 1 200 h. Moreover, the coating shows good thermal conductivity and static electricity properties, its thermal conductivity and electric resistivity are 21-37 W/(m·K) and 6.7×105-3.5×106 Ω.cm, respectively

  10. Multi-layer coatings

    Energy Technology Data Exchange (ETDEWEB)

    Maghsoodi, Sina; Brophy, Brenor L.; Abrams, Ze' ev R.; Gonsalves, Peter R.

    2016-06-28

    Disclosed herein are coating materials and methods for applying a top-layer coating that is durable, abrasion resistant, highly transparent, hydrophobic, low-friction, moisture-sealing, anti-soiling, and self-cleaning to an existing conventional high temperature anti-reflective coating. The top coat imparts superior durability performance and new properties to the under-laying conventional high temperature anti-reflective coating without reducing the anti-reflectiveness of the coating. Methods and data for optimizing the relative thickness of the under-layer high temperature anti-reflective coating and the top-layer thickness for optimizing optical performance are also disclosed.

  11. Electron beam processed plasticized epoxy coatings for surface protection

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, Mervat S. [National Center for Radiation Research and Technology, Nasr City (Egypt); Mohamed, Heba A., E-mail: hebaamohamed@gmail.com [National Research Center, Dokki (Egypt); Kandile, Nadia G. [University College for Girls, Ain Shams University (Egypt); Said, Hossam M.; Mohamed, Issa M. [National Center for Radiation Research and Technology, Nasr City (Egypt)

    2011-10-17

    Highlights: {center_dot} Coating formulations with EA 70%, HD 20%, and castor oil 10% under 1 Mrad pass{sup -1} irradiation dose showed the best adhesion and passed bending tests. {center_dot} The prepared EP-SF-An adduct improve anti-corrosion properties of coatings without any significant effect on physical, mechanical and chemical properties of the cured film. The optimum amount of aniline adduct as corrosion inhibitor was found to be 0.4 g for 100 g of coating formulation. {center_dot} The corrosion inhibition efficiency of the prepared adduct competed the commercial efficiency. - Abstract: Epoxy acrylate oligomer (EA) was plasticized by adding different plasticizers such as epoxidized soybean oil, glycerol and castor oil and cured by electron beam (EB). Different irradiation doses (1, 2.5 and 5 Mrad pass{sup -1}) were used in the curing process. The effect of both different irradiation doses and plasticizers on the end use performance properties of epoxy acrylate coating namely, pencil hardness, bending test, adhesion test, acid and alkali resistance test were studied. It was observed that incorporation of castor oil in epoxy acrylate diluted by 1,6-hexanediol diacrylate (HD) monomer with a ratio (EA 70%, HD 20%, castor oil 10%) under 1 Mrad pass{sup -1} irradiation dose improved the physical, chemical and mechanical properties of cured films than the other plasticizer. Sunflower free fatty acid was epoxidized in situ under well established conditions. The epoxidized sunflower free fatty acids (ESFA) were subjected to react with aniline in sealed ampoules under inert atmosphere at 140 deg. C. The produced adducts were added at different concentrations to epoxy acrylate coatings under certain EB irradiation dose and then evaluated as corrosion inhibitors for carbon steel surfaces in terms of weight loss measurements and corrosion resistance tests. It was found that, addition of 0.4 g of aniline adduct to 100 g epoxy acrylate formula may give the best corrosion

  12. Preparation of corrosion-resistant and conductive trivalent Cr-C coatings on 304 stainless steel for use as bipolar plates in proton exchange membrane fuel cells by electrodeposition

    Science.gov (United States)

    Wang, Hsiang-Cheng; Sheu, Hung-Hua; Lu, Chen-En; Hou, Kung-Hsu; Ger, Ming-Der

    2015-10-01

    In this study, Cr-C-coated bipolar plates are produced by electroplating on the SS304 plates with a machined flow channel. The resulting plates were tested using potentiodynamic and potentiostatic measurements in simulated PEMFC environments, which show that the bipolar plate coated with Cr-C exhibited good anticorrosion performance. The corrosive current density of the Cr-C coating formed for a plating time of 10 min for 10 h exhibits a low stable value of 1.51 × 10-10 A/cm2 during the potentiostatic test in a 0.5 M H2SO4 + 2 ppm HF solution at 70 °C with an air purge, indicating that the Cr-C coating plated for 10 min is stable in a cathode environment. The interfacial contact resistance (ICR) of the bipolar plate with the Cr-C coating clearly improved, presenting an ICR of 19.52 mΩ cm2 at a pressure of 138 N/cm2. The results from scanning electron microscopy (SEM) and ICR before and after the corrosion tests indicate that the bipolar plate with the Cr-C coating is electrochemically stable. In this study, the maximum power density (212.41 mW/cm2) is obtained at a cell temperature of 80 °C and a gas flow rate of 300 standard cubic centimeters per minute (sccm) when Cr-C coated SS304 bipolar plates were used.

  13. Flow coating apparatus and method of coating

    Science.gov (United States)

    Hanumanthu, Ramasubrahmaniam; Neyman, Patrick; MacDonald, Niles; Brophy, Brenor; Kopczynski, Kevin; Nair, Wood

    2014-03-11

    Disclosed is a flow coating apparatus, comprising a slot that can dispense a coating material in an approximately uniform manner along a distribution blade that increases uniformity by means of surface tension and transfers the uniform flow of coating material onto an inclined substrate such as for example glass, solar panels, windows or part of an electronic display. Also disclosed is a method of flow coating a substrate using the apparatus such that the substrate is positioned correctly relative to the distribution blade, a pre-wetting step is completed where both the blade and substrate are completed wetted with a pre-wet solution prior to dispensing of the coating material onto the distribution blade from the slot and hence onto the substrate. Thereafter the substrate is removed from the distribution blade and allowed to dry, thereby forming a coating.

  14. Effect of electrolysis superheat degree on anticorrosion performance of 5Cu/(10NiO-NiFe2O4) cermet inert anode

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    5Cu/(10NiO-NiFe2O4) cermet inert anodes were prepared by cold-pressing and sintering process, and the effect of superheat degree of melting K3AIF6-Na3AlF6-AlF3 on their anticorrosion performance was studied under electrolysis conditions. The results show that, the fluctuation of cell becomes small with increasing of superheat degree, which is helpful to inhibit the formation of cathodic encrustation; the concentration of impurities from inert anode in bath goes up to certain degree, but it is far smaller than those in traditional high-temperature bath. Increasing the superheat degree of melting K3AlF6-Na3AlF6-AlF3 has unconspicuous effect on the contents of impurities in cathodic aluminum. The total mass fractions of Fe, Ni and Cu in aluminum are 15.38% and15.09% respectively under superheat degree of 95 and 195 ℃C. From micro-topography of anode used view, increasing the superheat degree can aggravate corrosion of metal Cu in inert anode, and has negative influence on electrical conductivity of electrode to some extent.

  15. European coatings conference - Marine coatings. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    This volume contains 13 lectures (manuscripts or powerpoint foils) with the following topics: 1. Impact of containerization on polyurethane and polyurea in marine and protective coatings (Malte Homann); 2. The application of combinatorial/high-throughput methods to the development of marine coatings (Bret Chisholm); 3. Progress and perspectives in the AMBIO (advanced nanostructured surfaces for the control of biofouling) Project (James Callow); 4. Release behaviour due to shear and pull-off of silicone coatings with a thickness gradient (James G. Kohl); 5. New liquid rheology additives for high build marine coatings (Andreas Freytag); 6. Effective corrosion protection with polyaniline, polpyrrole and polythiophene as anticorrosice additives for marine paints (Carlos Aleman); 7. Potential applications of sol gel technology for marine applications (Robert Akid); 8: Performance of biocide-free Antifouling Coatings for leisure boats (Bernd Daehne); 9. Novel biocidefree nanostructured antifouling coatings - can nano do the job? (Corne Rentrop); 10. One component high solids, VOC compliant high durability finish technology (Adrian Andrews); 11. High solid coatings - the hybrid solution (Luca Prezzi); 12. Unique organofunctional silicone resins for environmentally friendly high-performance coatings (Dieter Heldmann); 13. Silicone-alkyd paints for marine applications: from battleship-grey to green (Thomas Easton).

  16. Corrosion inhibiting organic coatings

    Energy Technology Data Exchange (ETDEWEB)

    Sasson, E.

    1984-10-16

    A corrosion inhibiting coating comprises a mixture of waxes, petroleum jelly, a hardener and a solvent. In particular, a corrosion inhibiting coating comprises candelilla wax, carnauba wax, microcrystalline waxes, white petrolatum, an oleoresin, lanolin and a solvent.

  17. PROPERTIES OF ORGANIC COATINGS CONTAINING PIGMENTS WITH SURFACE MODIFIED WITH A LAYER OF ZnFe2O4

    Directory of Open Access Journals (Sweden)

    Kateřina Nechvílová

    2015-11-01

    Full Text Available This work is focussed on the properties of organic coatings containing pigments whose surface was chemically coated with zinc ferrite (ZnFe2O4 layer. Four silicate types with different particle shapes were selected as the cores: diatomite, talc, kaolin and wollastonite. The untreated particles exhibit a barrier effect. The aim of this project was to apply the surface treatment approach with a view to enhancing not only the model paint films’ anticorrosion properties but also their resistance to physico- mechanical tests pursuant to ISO standards (cupping, bending, impact, adhesion. Other parameters examined included: particle size and morphology, density of the modified pigment, oil consumption, pH, conductivity, and electrochemical properties of the paint film. A solvent-based epoxy-ester resin was used as the binder and also served as the reference material. The pigment volume concentration (PVC was 1% and 10%. During the last stage of the experiment, the paint films were exposed to a corrosive environment stimulating seaside conditions or conditions roads treated with rock salt. The accelerated cyclic corrosion test in a neutral salt mist atmosphere was conducted for 864 hours. The results served to ascertain a suitable environment for organic coatings.

  18. Vegetable-Oil-Based Hyperbranched Polyester-Styrene Copolymer Containing Silver Nanoparticle as Antimicrobial and Corrosion-Resistant Coating Materials

    Directory of Open Access Journals (Sweden)

    Manawwer Alam

    2013-01-01

    Full Text Available Pongamia oil (PO was converted to Pongamia oil hydroxyl (POH via epoxidation process. The esterification of POH with linolenic acid was carried out to form hyperbranched polyester (HBPE, and further styrenation was performed at the conjugated double bond in the chain of linolenic acid. After styrenation, silver nanoparticle was added in different weight percentages (0.1–0.4 wt%. The structural elucidation of POH, HBPE, and HBPE-St was carried out by FT-IR, 1H-NMR, and 13C-NMR spectroscopic techniques. Physicochemical and physicomechanical analyses were performed by standard method. Thermal behavior of the HBPE-St was analyzed by using thermogravimetric analysis (TGA and differential scanning calorimetry (DSC. The coatings of HBPE-St were prepared on mild steel strips. The anticorrosive behavior of HBPE-St resin-based coatings in acid, saline, and tap water was evaluated, and the molecular weight of HBPE-St was determined by gel permeation chromatography (GPC. The antibacterial activities of the HBPE-St copolymers were tested in vitro against bacteria and fungi by disc diffusion method. The HBPE-St copolymers exhibited good antibacterial activities and can be used as antimicrobial and corrosion-resistant coating materials.

  19. Improvement of Electrochemical Surface Properties in Steel Substrates Using a Nanostructured CrN/AlN Multilayer Coating

    Science.gov (United States)

    Cabrera, G.; Torres, F.; Caicedo, J. C.; Aperador, W.; Amaya, C.; Prieto, P.

    2012-01-01

    Improvement of corrosion properties on AISI D3 steel surfaces coated with [CrN/AlN] n multilayered system deposited for various periods (Λ) via magnetron sputtering has been studied in this work exhaustively. For practical effects compared were the latter properties with CrN and AlN single layers deposited with the same conditions as the multilayered systems. The coatings were characterized in terms of crystal phase; chemical composition, micro-structural, and electrochemical properties by x-ray diffractometry, energy dispersive x-ray, Fourier transforming infrared spectroscopy, atomic force microscopy, scanning electron microscopy, Tafel polarization curves, and electrochemical impedance spectroscopy. Corrosion evolution was observed via optical microscopy. Results from x-ray diffractometry analysis revealed that the crystal structure of [CrN/AlN] n multilayered coatings has an NaCl-type lattice structure and hexagonal structure (wurtzite-type) for CrN and AlN, respectively, i.e., it was made non-isostructural multilayered. The best behavior was obtained by the multilayered period: Λ = 60 nm (50 bilayers), showing the maximum corrosion resistance (polarization resistance of 1.18 KΩ, and corrosion rate of 1.02 mpy). Those results indicated an improvement of anticorrosive properties, compared to the CrN/AlN multilayer system with 1 bilayer at 98 and 80%, respectively. Furthermore, the corrosion resistance of steel AISI D3 is improved beyond 90%. These improvement effects in multilayered coatings could be attributed to the number of interfaces that act as obstacles for the inward and outward diffusions of ion species, generating an increment in the energy or potential required for translating the corrosive ions across the coating/substrate interface. Moreover, the interface systems affect the means free path on the ions toward the metallic substrate, due to the decreasing of the defects presented in the multilayered coatings.

  20. Coatings: Pt. 4

    International Nuclear Information System (INIS)

    The demands imposed on the coating industry to reduce environmental pollution and energy consumption and to produce high quality coatings in an era where the cost of raw materials increases continuously, have stimulated interest and research in radiation curing methods for coatings. Radiation such as ionising radiation, visible light, infra red and micro waves can be applied. In this article attention is given to electron beam curing and special reference is made to modern wood coating equipment

  1. PIT Coating Requirements Analysis

    Energy Technology Data Exchange (ETDEWEB)

    MINTEER, D.J.

    2000-10-20

    This study identifies the applicable requirements for procurement and installation of a coating intended for tank farm valve and pump pit interior surfaces. These requirements are intended to be incorporated into project specification documents and design media. This study also evaluates previously recommended coatings and identifies requirement-compliant coating products.

  2. PIT Coating Requirements Analysis

    International Nuclear Information System (INIS)

    This study identifies the applicable requirements for procurement and installation of a coating intended for tank farm valve and pump pit interior surfaces. These requirements are intended to be incorporated into project specification documents and design media. This study also evaluates previously recommended coatings and identifies requirement-compliant coating products

  3. Fuel particle coating data

    International Nuclear Information System (INIS)

    Development of coating on nuclear fuel particles for the High-Temperature Fuels Technology program at the Los Alamos Scientific Laboratory included process studies for low-density porous and high-density isotropic carbon coats, and for ZrC and ''alloy'' C/ZrC coats. This report documents the data generated by these studies

  4. Ceramic with zircon coating

    Science.gov (United States)

    Wang, Hongyu (Inventor)

    2003-01-01

    An article comprises a silicon-containing substrate and a zircon coating. The article can comprise a silicon carbide/silicon (SiC/Si) substrate, a zircon (ZrSiO.sub.4) intermediate coating and an external environmental/thermal barrier coating.

  5. Mechanism of (NH{sub 4})S{sub 2}O{sub 8} to enhance the anti-corrosion performance of Mo-Ce inhibitor on X80 steel in acid solution

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Yanhua [School of Materials Science and Engineering, Southwest Petroleum University, Chengdu 610500 (China); Zhuang, Jia, E-mail: zj-656@163.com [School of Materials Science and Engineering, Southwest Petroleum University, Chengdu 610500 (China); Zeng, Xianguang [Material Corrosion and Protection Key Laboratory of Sichuan Province, Zigong 643000 (China); Institute of Materials and Chemical Engineering, Sichuan University of Science and Engineering, Zigong 643000 (China)

    2014-09-15

    Highlights: • The 1000 mg/L Na{sub 2}MoO{sub 4} and 500 mg/L Ce(NO{sub 3}){sub 3} has best synergistic effect. • The (NH{sub 4}){sub 2}S{sub 2}O{sub 8} made the valence transformation of cerium (Ce{sup 3+} → Ce{sup 4+}) come true. • The anti-corrosion performance of Mo-Ce inhibitor was improved by (NH{sub 4}){sub 2}S{sub 2}O{sub 8}. • The coordination ability of inhibitor complexes was improved by (NH{sub 4}){sub 2}S{sub 2}O{sub 8}. • The bonding force and adsorption between inhibitor and steel surface was enhanced. - Abstract: Ce(NO{sub 3}){sub 3} and Na{sub 2}MoO{sub 4} are adopted to form (Mo-Ce) composite corrosion inhibitor in allusion to the corrosion problem of steel in acidic conditions. The experimental results showed that the anticorrosion effects were enhanced and the inhibition efficiencies were increased by (NH{sub 4}){sub 2}S{sub 2}O{sub 8}. The reason of enhancement is the increase of coordination bonds amount between Ce{sup 4+} and MoO{sub 4}{sup 2−}, the augment of combining sites of interface between anti-corrosion film and steel, and the reinforce of adsorption caused by the transformation of Ce{sup 3+} to Ce{sup 4+} by oxidants. The process and conditions for transformation of Ce{sup 3+} to Ce{sup 4+} and formation of complexes are discussed. The related thermodynamic and kinetic parameters are calculated and the possibility for (NH{sub 4}){sub 2}S{sub 2}O{sub 8} to improve the performance of Mo-Ce corrosion inhibitor is proved.

  6. Optical Properties of Window Coatings

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Window coating used for the building in recent years is described. Important design principles, practical coating materials, and attainable optical properties for research-type coatings are introduced. Discussion is carried out on the spectrally selective coatings, the electrochromic coatings, and the thermochromic coatings.

  7. Antibacterial polymer coatings.

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Mollye C.; Allen, Ashley N.; Barnhart, Meghan; Tucker, Mark David; Hibbs, Michael R.

    2009-09-01

    A series of poly(sulfone)s with quaternary ammonium groups and another series with aldehyde groups are synthesized and tested for biocidal activity against vegetative bacteria and spores, respectively. The polymers are sprayed onto substrates as coatings which are then exposed to aqueous suspensions of organisms. The coatings are inherently biocidal and do not release any agents into the environment. The coatings adhere well to both glass and CARC-coated coupons and they exhibit significant biotoxicity. The most effective quaternary ammonium polymers kills 99.9% of both gram negative and gram positive bacteria and the best aldehyde coating kills 81% of the spores on its surface.

  8. Metallic coating of microspheres

    International Nuclear Information System (INIS)

    Extremely smooth, uniform metal coatings of micrometer thicknesses on microscopic glass spheres (microspheres) are often needed as targets for inertial confinement fusion (ICF) experiments. The first part of this paper reviews those methods used successfully to provide metal coated microspheres for ICF targets, including magnetron sputtering, electro- and electroless plating, and chemical vapor pyrolysis. The second part of this paper discusses some of the critical aspects of magnetron sputter coating of microspheres, including substrate requirements, the sticking of microspheres during coating (preventing a uniform coating), and the difficulties in growing the desired dense, smooth, uniform microstructure on continuously moving spherical substrates

  9. ATHENA optimized coating design

    DEFF Research Database (Denmark)

    Ferreira, Desiree Della Monica; Christensen, Finn Erland; Jakobsen, Anders Clemen;

    2012-01-01

    The optimization of coating design for the ATHENA mission si described and the possibility of increasing the telescope effective area in the range between 0.1 and 10 keV is investigated. An independent computation of the on-axis effective area based on the mirror design of ATHENA is performed in...... order to review the current coating baseline. The performance of several material combinations, considering a simple bi-layer, simple multilayer and linear graded multilayer coatings are tested and simulation of the mirror performance considering both the optimized coating design and the coating...

  10. Excellent anti-corrosive pretreatment layer on iron substrate based on three-dimensional porous phytic acid/silane hybrid

    Science.gov (United States)

    Gao, Xiang; Lu, Ke; Xu, Lei; Xu, Hua; Lu, Haifeng; Gao, Feng; Hou, Shifeng; Ma, Houyi

    2016-01-01

    A novel, highly effective and environmentally friendly film-forming material, phytic acid (PA)/silane (denoted as PAS) hybrid with a three-dimensional (3D) network structure, was prepared through a condensation reaction of PA with methyltrihydroxysilane generated from the hydrolysis of methyltriethoxysilane (MTES). Two kinds of PAS-based pretreatment layers, namely NaBrO3-free and NaBrO3-doped PAS layers, were fabricated on iron substrates using the dip-coating method. SEM and AFM observations showed that the as-fabricated PAS-based layers possessed a 3D porous microstructure at the nanoscale and a rough surface morphology. X-ray photoelectron spectroscopic (XPS) and attenuated total reflection infrared (ATR-IR) spectroscopic characterization demonstrated that the above PAS layers bound to the iron surface via the -P-O- bond. Moreover, analyses of steady-state polarization curves and electrochemical impedance spectroscopic (EIS) data indicated that the corrosion rates of the iron substrates decreased considerably in the presence of the two PAS-based pretreatment layers. In particular, the NaBrO3-dosed PAS layer displayed the better corrosion resistance ability as well as maintaining the original microstructure and surface morphology. The PAS-based pretreatment layers are expected to act as substitutes for chromate and phosphate conversion layers and will find widespread application in the surface pretreatment of iron and steel materials due to the advantages of being environmentally friendly, the rapid film-forming process, and, especially, the nanoporous microstructure and rough surface morphology.A novel, highly effective and environmentally friendly film-forming material, phytic acid (PA)/silane (denoted as PAS) hybrid with a three-dimensional (3D) network structure, was prepared through a condensation reaction of PA with methyltrihydroxysilane generated from the hydrolysis of methyltriethoxysilane (MTES). Two kinds of PAS-based pretreatment layers, namely Na

  11. The existence of large magnetocaloric effect at low field variation and the anti-corrosion ability of Fe-rich alloy with Cr substituted for Fe

    International Nuclear Information System (INIS)

    The influence of Cr substituted for Fe in Fe78-xCrxSi4Nb5B12Ag1 ribbons on the crystallization and magnetic properties including the magnetocaloric effect have been investigated. DSC measurements showed that the crystallization temperature and the crystallization activation energy increased with Cr content. Thermomagnetic curves measured in low applied field indicated that there is a sharp ferromagnetic-paramagnetic phase transition at Curie temperature, TC, of the amorphous phase. In addition, substitution of Cr for Fe led to approximate linear decrease of TC with Cr content, namely from 450K to 280K for x = 0 and x = 8, respectively. From a series of the isothermal magnetization curves M(H) measured at different temperatures, magnetic entropy change ΔSm was determined at magnetic field variations of 13.5, 10.0 and 5.0 kOe. Maximum value of ΔSm (occurred near TC) decreased with increasing Cr content and these values established are quite large at low field variation. Namely, at moderate low magnetic field variation of 5.0 kOe, |ΔSm|max is of 4.4 and 1.9 J/kg.K for x = 0 and x = 8, respectively. Our studied alloys system could be considered as the best magnetocaloric material candidates for magnetic refrigeration because of colossal magnetic entropy change at low field variation and working temperature could be controlled in large region by substitution effect. The anti-corrosion ability of alloys was also examined.

  12. Excellent anti-corrosive pretreatment layer on iron substrate based on three-dimensional porous phytic acid/silane hybrid.

    Science.gov (United States)

    Gao, Xiang; Lu, Ke; Xu, Lei; Xu, Hua; Lu, Haifeng; Gao, Feng; Hou, Shifeng; Ma, Houyi

    2016-01-21

    A novel, highly effective and environmentally friendly film-forming material, phytic acid (PA)/silane (denoted as PAS) hybrid with a three-dimensional (3D) network structure, was prepared through a condensation reaction of PA with methyltrihydroxysilane generated from the hydrolysis of methyltriethoxysilane (MTES). Two kinds of PAS-based pretreatment layers, namely NaBrO3-free and NaBrO3-doped PAS layers, were fabricated on iron substrates using the dip-coating method. SEM and AFM observations showed that the as-fabricated PAS-based layers possessed a 3D porous microstructure at the nanoscale and a rough surface morphology. X-ray photoelectron spectroscopic (XPS) and attenuated total reflection infrared (ATR-IR) spectroscopic characterization demonstrated that the above PAS layers bound to the iron surface via the -P-O- bond. Moreover, analyses of steady-state polarization curves and electrochemical impedance spectroscopic (EIS) data indicated that the corrosion rates of the iron substrates decreased considerably in the presence of the two PAS-based pretreatment layers. In particular, the NaBrO3-dosed PAS layer displayed the better corrosion resistance ability as well as maintaining the original microstructure and surface morphology. The PAS-based pretreatment layers are expected to act as substitutes for chromate and phosphate conversion layers and will find widespread application in the surface pretreatment of iron and steel materials due to the advantages of being environmentally friendly, the rapid film-forming process, and, especially, the nanoporous microstructure and rough surface morphology. PMID:26689810

  13. Coated Aerogel Beads

    Science.gov (United States)

    Littman, Howard (Inventor); Plawsky, Joel L. (Inventor); Paccione, John D. (Inventor)

    2014-01-01

    Methods and apparatus for coating particulate material are provided. The apparatus includes a vessel having a top and a bottom, a vertically extending conduit having an inlet in the vessel and an outlet outside of the vessel, a first fluid inlet in the bottom of the vessel for introducing a transfer fluid, a second fluid inlet in the bottom of the vessel for introducing a coating fluid, and a fluid outlet from the vessel. The method includes steps of agitating a material, contacting the material with a coating material, and drying the coating material to produce a coated material. The invention may be adapted to coat aerogel beads, among other materials. A coated aerogel bead and an aerogel-based insulation material are also disclosed.

  14. Combustion chemical vapor desposited coatings for thermal barrier coating systems

    Energy Technology Data Exchange (ETDEWEB)

    Hampikian, J.M.; Carter, W.B. [Georgia Institute of Technology, Atlanta, GA (United States)

    1995-10-01

    The new deposition process, combustion chemical vapor deposition, shows a great deal of promise in the area of thermal barrier coating systems. This technique produces dense, adherent coatings, and does not require a reaction chamber. Coatings can therefore be applied in the open atmosphere. The process is potentially suitable for producing high quality CVD coatings for use as interlayers between the bond coat and thermal barrier coating, and/or as overlayers, on top of thermal barrier coatings.

  15. Preliminary coating design and coating developments for ATHENA

    DEFF Research Database (Denmark)

    Jakobsen, Anders Clemen; Ferreira, Desiree Della Monica; Christensen, Finn Erland;

    2011-01-01

    We present initial novel coating design for ATHENA. We make use of both simple bilayer coatings of Ir and B4C and more complex constant period multilayer coatings to enhance the effective area and cover the energy range from 0.1 to 10 keV. We also present the coating technology used for these...... designs and present test results from coatings....

  16. Research and Application Status of Osmotic Organosilieon Protective Surface Coatings%渗透性有机硅表面防护涂料的研究及应用现状

    Institute of Scientific and Technical Information of China (English)

    孙高霞; 孙红尧; 陆采荣

    2009-01-01

    The corrosion mechanism of concrete and the protective mechanism of organosilicone coatings are summarized. In accordance with the different composition forms, organosilicone protective coatings may be divided into water-based, solvent-based and emulsion-based coatings. Their action principles, advantages and disadvantages are described respectively. The research status, existing products in the market and the normative standards of performance tests of organosilicone protective coatings are also introduced. As an effective anti-corrosion method, organosilicone protective coatings have been widely used in engineering.%阐述了混凝土的腐蚀机理和工程中得到广泛应用的渗透性有机硅涂料的防护机理;并对水性、溶剂型和乳液型三种有机硅防护涂料的作用原理和使用性能及其研究状况、市售产品和性能检测标准进行了介绍.

  17. Experimental Investigation on Addition of Anticorrosive Agent in a 50-MW Biomass-Fired Circulating Fluidized Bed Boiler%生物质循环流化床锅炉掺烧防腐蚀剂的试验研究

    Institute of Scientific and Technical Information of China (English)

    宋景慧; 谭巍

    2014-01-01

    Experiments on combustion of pure biomass and biomass with anticorrosive agent were carried out in a 50-MW biomass-fired circulating fluidized bed boiler. The anticorrosive agent has a porous structure and mainly contains magnesium oxide (MgO), kaolin, activated alumina (Al2O3) and foamer. Results obtained in experiments show that, boiler thermal efficiency was weakly influenced by the anticorrosive agent, and contents of K and Cl in flue ash decreased as contrast to the increase of K and Cl in furnace slag. When the mass percentage of anticorrosive agent is 3%, in the flue ash, the K values ranged from 7.62%to 5.69%, and Cl values reduced from 3.86%to 2.35%. While in furnace slag, the values K varied from 4.03%to 4.71%, and Cl values increased from 756.58 mg/kg to 1 121.31 mg/kg. Due to the anticorrosive agent, the content of HCl in flue gas decreased from 25 mg/Nm3 to 15 mg/Nm3, as the emission of NO increased from 268 mg/Nm3 to 309 mg/Nm3.%在亚洲最大的50 MW生物质循环流化床直燃锅炉上进行了掺烧防腐蚀剂的燃烧试验,防腐蚀剂采用多孔膜结构,主要成分是MgO、高岭土、活性Al2O3和发泡剂,试验结果表明:掺烧防腐蚀剂不会降低锅炉热效率,且能够有效地降低飞灰中K、Cl元素的含量,将其固留在炉渣中。当防腐蚀剂添加量占总燃料质量的3%时,飞灰中的K元素含量由7.62%下降为5.69%,Cl元素含量由3.86%下降为2.35%;而炉渣中的K元素含量由4.03%上升为4.71%,Cl元素含量由756.58 mg/kg上升为1121.31 mg/kg;同时烟气中的HCl排放量由25 mg/Nm3下降为15 mg/Nm3,NO含量由268 mg/Nm3上升为309 mg/Nm3。

  18. Biocompatibility of Niobium Coatings

    OpenAIRE

    René Olivares-Navarrete; Jhon Jairo Olaya; Claudia Ramírez; Sandra Elizabeth Rodil

    2011-01-01

    Niobium coatings deposited by magnetron sputtering were evaluated as a possible surface modification for stainless steel (SS) substrates in biomedical implants. The Nb coatings were deposited on 15 mm diameter stainless steel substrates having an average surface roughness of 2 mm. To evaluate the biocompatibility of the coatings three different in vitro tests, using human alveolar bone derived cells, were performed: cellular adhesion, proliferation and viability. Stainles...

  19. Oxide coating development

    Energy Technology Data Exchange (ETDEWEB)

    Stinton, D.P.

    1995-06-01

    Monolithic SiC heat exchangers and fiber-reinforced SiC-matrix composite heat exchangers and filters are susceptible to corrosion by alkali metals at elevated temperatures. Protective coatings are currently being developed to isolate the SiC materials from the corrodants. Unfortunately, these coatings typically crack and spall when applied to SiC substrates. The purpose of this task is to determine the feasibility of using a compliant material between the protective coating and the substrate. The low-modulus compliant layer could absorb stresses and eliminate cracking and spalling of the protective coatings.

  20. Superhard Nanocomposite Coatings

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The recent development in the field of nanocomposite coatings with good mechanical properties is critically reviewed in this paper. The design principle and materials selection for the nanocomposite coatings are introduced. Different methods for the preparation of superhard nanocomposite coatings are described with emphasis on the magnetron sputtering. Based on recent theoretical and experimental results regarding the appearance of superhardness in nanocomposite coating, lattice parameter changes, crystallite size, microstructure and morphology are reviewed in detail. Also emphasized are the mechanical properties (especially on hardness) and the ways by which the properties are derived.

  1. Innovations in coating technology.

    Science.gov (United States)

    Behzadi, Sharareh S; Toegel, Stefan; Viernstein, Helmut

    2008-01-01

    Despite representing one of the oldest pharmaceutical techniques, coating of dosage forms is still frequently used in pharmaceutical manufacturing. The aims of coating range from simply masking the taste or odour of drugs to the sophisticated controlling of site and rate of drug release. The high expectations for different coating technologies have required great efforts regarding the development of reproducible and controllable production processes. Basically, improvements in coating methods have focused on particle movement, spraying systems, and air and energy transport. Thereby, homogeneous distribution of coating material and increased drying efficiency should be accomplished in order to achieve high end product quality. Moreover, given the claim of the FDA to design the end product quality already during the manufacturing process (Quality by Design), the development of analytical methods for the analysis, management and control of coating processes has attracted special attention during recent years. The present review focuses on recent patents claiming improvements in pharmaceutical coating technology and intends to first familiarize the reader with the available procedures and to subsequently explain the application of different analytical tools. Aiming to structure this comprehensive field, coating technologies are primarily divided into pan and fluidized bed coating methods. Regarding pan coating procedures, pans rotating around inclined, horizontal and vertical axes are reviewed separately. On the other hand, fluidized bed technologies are subdivided into those involving fluidized and spouted beds. Then, continuous processing techniques and improvements in spraying systems are discussed in dedicated chapters. Finally, currently used analytical methods for the understanding and management of coating processes are reviewed in detail in the last section of the review. PMID:19075909

  2. EIS investigation of the corrosion resistance of uncoated and coated Nd-Fe-B magnets in PBS solution

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Emerson A.; Oliveira, Mara C.L.; Rossi, Jesualdo L.; Costa, Isolda, E-mail: emerson.martins@usp.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), SP (Brazil). Centro de Ciencia e Tecnologia de Materiais. Lab. de Corrosao; Melo, Hercilio G. de, E-mail: hgdemelo@usp.b [Universidade de Sao Paulo (EP/USP), SP (Brazil). Dept. de Engenharia Quimica. Lab. de Eletroquimica e Corrosao

    2011-07-01

    The aim of this work is to investigate the corrosion behavior of powder metallurgy produced Nd-Fe-B magnets and to evaluate the corrosion protection afforded by two different surface treatments: a phosphate conversion and a non-functional silane (BTSE) layer. The electrochemical tests were performed in a phosphate buffered solution (PBS) at neutral pH, which ionic concentration coincides with that of the human body. The corrosion behavior was monitored by means of electrochemical impedance spectroscopy (EIS) and anodic potentiodynamic polarization curves, and SEM-EDS analyses were used to monitor coating deposition. EIS response has evidenced a porous electrode behavior for the Nd-Fe-B magnets according to the de Levie theory. The results also indicated a good performance of the phosphate layer, whereas the BTSE layer did not improve the corrosion resistance of the magnets. The good anticorrosion performance of the phosphate layer was explained on the basis of the formation of an insoluble phosphate layer both on the electrode surface (identified by interference colors) and on the pore walls. Precipitation of insoluble Nd phosphate on the Nd-rich phase also contributes to the superior corrosion protection afforded by this coating. (author)

  3. Superhydrophobic silica coating by dip coating method

    International Nuclear Information System (INIS)

    Herein, we report a simple and low cost method for the fabrication of superhydrophobic coating surface on quartz substrates via sol-gel dip coating method at room temperature. Desired surface chemistry and texture growth for superhydrophobicity developed under double step sol–gel process at room temperature. The resultant superhydrophobic surfaces were characterized by Field-emission scanning electron microscopy (FE-SEM), Atomic force microscopy (AFM), water contact angle (WCA) measurement, differential thermal gravimetric analysis-differential thermal analysis (TGA-DTA) calorimetry and optical spectrometer. Coating shows the ultra high water contact angle about 168 ± 2° and water sliding angle 3 ± 1° and superoleophilic with petroleum oils. This approach allows a simple strategy for the fabrication process of superhydrophilic–superhydrophobic on same surfaces with high thermal stability of superhydrophobicity up to 560 °C. Thus, durability, special wettability and thermal stability of superhydrophobicity expand their application fields.

  4. Mechanically Invisible Polymer Coatings

    DEFF Research Database (Denmark)

    2014-01-01

    phase comprises particles, said particles comprising a filler material and an encapsulating coating of a second polymeric material, wherein the backbones of the first and second polymeric materials are the same. The composition may be used in electroactive polymers (EAPs) in order to obtain mechanically...... invisible polymer coatings....

  5. Molecular Adsorber Coating

    Science.gov (United States)

    Straka, Sharon; Peters, Wanda; Hasegawa, Mark; Hedgeland, Randy; Petro, John; Novo-Gradac, Kevin; Wong, Alfred; Triolo, Jack; Miller, Cory

    2011-01-01

    A document discusses a zeolite-based sprayable molecular adsorber coating that has been developed to alleviate the size and weight issues of current ceramic puck-based technology, while providing a configuration that more projects can use to protect against degradation from outgassed materials within a spacecraft, particularly contamination-sensitive instruments. This coating system demonstrates five times the adsorption capacity of previously developed adsorber coating slurries. The molecular adsorber formulation was developed and refined, and a procedure for spray application was developed. Samples were spray-coated and tested for capacity, thermal optical/radiative properties, coating adhesion, and thermal cycling. Work performed during this study indicates that the molecular adsorber formulation can be applied to aluminum, stainless steel, or other metal substrates that can accept silicate-based coatings. The coating can also function as a thermal- control coating. This adsorber will dramatically reduce the mass and volume restrictions, and is less expensive than the currently used molecular adsorber puck design.

  6. HA-Coated Implant

    DEFF Research Database (Denmark)

    Daugaard, Henrik; Søballe, Kjeld; Bechtold, Joan E

    2014-01-01

    The goal of osseointegration of orthopedic and dental implants is the rapid achievement of a mechanically stable and long lasting fixation between living bone and the implant surface. In total joint replacements of cementless designs, coatings of calcium phosphates were introduced as a means of...... evaluating bone-implant fixation with HA coatings....

  7. Coating of graphene

    NARCIS (Netherlands)

    Schneider, G.F.; Dekker, C.

    2014-01-01

    The present invention is in the field of highly crystalline graphene and coating said graphene with a layer. Said graphene may have further structures, such as nanopores, nanogaps, and nanoribbons. The coated graphene can be used for biomolecular analysis and modification, such as DNA-sequencing, as

  8. RADIATION-CURABLE COATINGS

    Science.gov (United States)

    The report gives results of an evaluation of radiation-curable coatings as a technology for reducing volatile organic compound (VOC) emissions from surface coating operations. urvey of the literature was conducted to assess the state of the technology and emissions from radiation...

  9. Rock-hard coatings

    NARCIS (Netherlands)

    Muller, M.

    2007-01-01

    Aircraft jet engines have to be able to withstand infernal conditions. Extreme heat and bitter cold tax coatings to the limit. Materials expert Dr Ir. Wim Sloof fits atoms together to develop rock-hard coatings. The latest invention in this field is known as ceramic matrix composites. Sloof has sign

  10. Catalytic thermal barrier coatings

    Science.gov (United States)

    Kulkarni, Anand A.; Campbell, Christian X.; Subramanian, Ramesh

    2009-06-02

    A catalyst element (30) for high temperature applications such as a gas turbine engine. The catalyst element includes a metal substrate such as a tube (32) having a layer of ceramic thermal barrier coating material (34) disposed on the substrate for thermally insulating the metal substrate from a high temperature fuel/air mixture. The ceramic thermal barrier coating material is formed of a crystal structure populated with base elements but with selected sites of the crystal structure being populated by substitute ions selected to allow the ceramic thermal barrier coating material to catalytically react the fuel-air mixture at a higher rate than would the base compound without the ionic substitutions. Precious metal crystallites may be disposed within the crystal structure to allow the ceramic thermal barrier coating material to catalytically react the fuel-air mixture at a lower light-off temperature than would the ceramic thermal barrier coating material without the precious metal crystallites.

  11. Charged-particle coating

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, W.L.; Crane, J.K.; Hendricks, C.D.

    1980-08-29

    Advanced target designs require thicker (approx. 300 ..mu..m) coatings and better surface finishes that can be produced with current coating techniques. An advanced coating technique is proposed to provide maximum control of the coating flux and optimum manipulation of the shell during processing. In this scheme a small beam of ions or particles of known incident energy are collided with a levitated spherical mandrel. Precise control of the incident energy and angle of the deposition flux optimizes the control of the coating morphology while controlled rotation and noncontact support of the shell minimizes the possibility of particulate or damage generated defects. Almost infinite variability of the incident energy and material in this process provides increased flexibility of the target designs which can be physically realized.

  12. Modern coating processes

    International Nuclear Information System (INIS)

    Articles collected in this volume explain both the present state of technique and current developments and problems in the environment of the following coating processes: - Hardfacing welding and soldering; - Thermal spraying; - Thin film technique (CVD, PVD); - Galvanising. Apart from basic representation of the conventional use of the different processes, both the new technological and material developments are to the fore. In this context, the purposeful post-treatment of coatings and the combination of different processes to achieve special coating properties should be mentioned. Examples of this show the hot isostatic pressing or laser melting of sprayed coatings, the simultaneous spraying and shot-blasting and the combination of galvanic and thin film techniques for the manufacture of hybrid systems. A further important group of subjects concerns the testing of various coatings. (orig.)

  13. Radiation curable coating compositions

    International Nuclear Information System (INIS)

    The present invention provides a low-toxicity diluent component for radiation curable coating compositions that contain an acrylyl or methacryly oligomer or resin component such as an acrylyl urethane oligomer. The low-toxicity diluent component of this invention is chosen from the group consisting of tetraethlorthosilicate and tetraethoxyethylorthosilicate. When the diluent component is used as described, benefits in addition to viscosity reduction, may be realized. Application characteristics of the uncured coatings composition, such as flowability, leveling, and smoothness are notably improved. Upon curing by exposure to actinic radiation, the coating composition forms a solid, non-tacky surface free of pits, fissures or other irregularities. While there is no readily apparent reactive mechanism by which the orthosilicate becomes chemically bonded to the cured coating, the presence of silicon in the cured coating has been confirmed by scanning electron microscopy. 12 drawing

  14. Charged-particle coating

    International Nuclear Information System (INIS)

    Advanced target designs require thicker (approx. 300 μm) coatings and better surface finishes that can be produced with current coating techniques. An advanced coating technique is proposed to provide maximum control of the coating flux and optimum manipulation of the shell during processing. In this scheme a small beam of ions or particles of known incident energy are collided with a levitated spherical mandrel. Precise control of the incident energy and angle of the deposition flux optimizes the control of the coating morphology while controlled rotation and noncontact support of the shell minimizes the possibility of particulate or damage generated defects. Almost infinite variability of the incident energy and material in this process provides increased flexibility of the target designs which can be physically realized

  15. Improving corrosion resistance of AZ31B magnesium alloy via a conversion coating produced by a protic ammonium-phosphate ionic liquid

    International Nuclear Information System (INIS)

    Magnesium alloys are susceptible to corrosion because of their high reactivity and low electrode potential. The present work introduces a conversion coating using a protic ammonium-phosphate ionic liquid (IL). Initial results on the AZ31B Mg alloy have demonstrated substantially improved corrosion resistance for the IL treatment at 300 °C (IL300C) compared to the treatment at room temperature. Potentiodynamic polarization analysis of the IL300C treated Mg surface in a NaCl solution exhibited a strong passivation behavior. No pretreatment is needed and the treated surface morphology is well preserved. Cross-sectional nanostructure examination using transmission electron microscopy and element mapping using energy-dispersive X-ray spectroscopy have revealed the IL300C conversion coating to be a 70–80 nm thick with a two-layer structure. Further surface chemical analysis using X-ray photoelectron spectroscopy suggested such an IL conversion coating possibly composed of metal oxides, metal phosphates, and carbonaceous compounds. - Highlights: • Anti-corrosion conversion film for Mg by a protic ammonium-phosphate ionic liquid • No pretreatment needed and no change in surface appearance and morphology • The ionic liquid conversion film of 70–80 nm thick and a two-layer structure

  16. Effect of the addition of thermally activated hydrotalcite on the protective features of sol-gel coatings applied on AA2024 aluminium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Collazo, A.; Hernandez, M.; Novoa, X.R. [Corrosion and Materials Engineering Group (ENCOMAT), ETSEI, University of Vigo, Campus Universitario, 36310 Vigo (Spain); Perez, C., E-mail: cperez@uvigo.es [Corrosion and Materials Engineering Group (ENCOMAT), ETSEI, University of Vigo, Campus Universitario, 36310 Vigo (Spain)

    2011-09-30

    The present work assesses the effect of the thermal activation of hydrotalcite particles when they are added to a hybrid sol-gel film to improve its corrosion properties. Although previous studies have demonstrated the anti-corrosion properties of as-synthesised hydrotalcite particles incorporated into sol-gel coatings, their inhibitive action has not been well-established. Some hypotheses suggest that it should be related to their anion exchange capacity, which increases when the hydrotalcite is thermally activated. Several techniques were used to characterise the uncalcined and calcined hydrotalcite: X-ray diffraction, Fourier transform infrared spectroscopy and thermogravimetric and differential scanning calorimetry techniques. To analyse the inhibition action, hybrid sol-gel coatings were doped with 10 wt% of CHT. Accelerated tests and electrochemical impedance spectroscopy were used for performance evaluation between the sol-gel coatings doped with calcined and uncalcined HT. The results obtained indicate the superior behaviour of samples doped with calcined HT at longer immersion times, which suggests better inhibition action.

  17. Improving corrosion resistance of AZ31B magnesium alloy via a conversion coating produced by a protic ammonium-phosphate ionic liquid

    Energy Technology Data Exchange (ETDEWEB)

    Elsentriecy, Hassan H. [Materials Science and Technology Division, Oak Ridge National Laboratory, TN (United States); Central Metallurgical Research and Development Institute, Cairo (Egypt); Qu, Jun, E-mail: qujn@ornl.gov [Materials Science and Technology Division, Oak Ridge National Laboratory, TN (United States); Luo, Huimin [Energy and Transportation Science Division, Oak Ridge National Laboratory, TN (United States); Meyer, Harry M.; Ma, Cheng; Chi, Miaofang [Materials Science and Technology Division, Oak Ridge National Laboratory, TN (United States)

    2014-10-01

    Magnesium alloys are susceptible to corrosion because of their high reactivity and low electrode potential. The present work introduces a conversion coating using a protic ammonium-phosphate ionic liquid (IL). Initial results on the AZ{sub 31}B Mg alloy have demonstrated substantially improved corrosion resistance for the IL treatment at 300 °C (IL{sub 3}00C) compared to the treatment at room temperature. Potentiodynamic polarization analysis of the IL{sub 3}00C treated Mg surface in a NaCl solution exhibited a strong passivation behavior. No pretreatment is needed and the treated surface morphology is well preserved. Cross-sectional nanostructure examination using transmission electron microscopy and element mapping using energy-dispersive X-ray spectroscopy have revealed the IL{sub 3}00C conversion coating to be a 70–80 nm thick with a two-layer structure. Further surface chemical analysis using X-ray photoelectron spectroscopy suggested such an IL conversion coating possibly composed of metal oxides, metal phosphates, and carbonaceous compounds. - Highlights: • Anti-corrosion conversion film for Mg by a protic ammonium-phosphate ionic liquid • No pretreatment needed and no change in surface appearance and morphology • The ionic liquid conversion film of 70–80 nm thick and a two-layer structure.

  18. Coating Reduces Ice Adhesion

    Science.gov (United States)

    Smith, Trent; Prince, Michael; DwWeese, Charles; Curtis, Leslie

    2008-01-01

    The Shuttle Ice Liberation Coating (SILC) has been developed to reduce the adhesion of ice to surfaces on the space shuttle. SILC, when coated on a surface (foam, metal, epoxy primer, polymer surfaces), will reduce the adhesion of ice by as much as 90 percent as compared to the corresponding uncoated surface. This innovation is a durable coating that can withstand several cycles of ice growth and removal without loss of anti-adhesion properties. SILC is made of a binder composed of varying weight percents of siloxane(s), ethyl alcohol, ethyl sulfate, isopropyl alcohol, and of fine-particle polytetrafluoroethylene (PTFE). The combination of these components produces a coating with significantly improved weathering characteristics over the siloxane system alone. In some cases, the coating will delay ice formation and can reduce the amount of ice formed. SILC is not an ice prevention coating, but the very high water contact angle (greater than 140 ) causes water to readily run off the surface. This coating was designed for use at temperatures near -170 F (-112 C). Ice adhesion tests performed at temperatures from -170 to 20 F (-112 to -7 C) show that SILC is a very effective ice release coating. SILC can be left as applied (opaque) or buffed off until the surface appears clear. Energy dispersive spectroscopy (EDS) and x-ray photoelectron spectroscopy (XPS) data show that the coating is still present after buffing to transparency. This means SILC can be used to prevent ice adhesion even when coating windows or other objects, or items that require transmission of optical light. Car windshields are kept cleaner and SILC effectively mitigates rain and snow under driving conditions.

  19. 钛白冷冻结晶罐钛材包覆搅拌器的应用技术%Application of Titanium Coated Agitator in Freezing and Crystallization Vessels for Titanium Dioxide

    Institute of Scientific and Technical Information of China (English)

    夏步前

    2001-01-01

    本文探讨了钛材在钛白冷冻结晶罐中防腐蚀的机理,提出了钛材用作防腐蚀层的搅拌包覆层的结构设计,制造技术及成本和可靠性分析。%The anticorrosion mechanism of titanium naterial in the freezingand crystallization vessels for titanium dioxide was discussed in this article.The structural design of using titanium as the coated layer to protect corrosion for the agitator,the fabrication thechnique and the method for the cost analysis and reliability analysis were also introduced.

  20. Fluorine Based Superhydrophobic Coatings

    Directory of Open Access Journals (Sweden)

    Jean-Denis Brassard

    2012-05-01

    Full Text Available Superhydrophobic coatings, inspired by nature, are an emerging technology. These water repellent coatings can be used as solutions for corrosion, biofouling and even water and air drag reduction applications. In this work, synthesis of monodispersive silica nanoparticles of ~120 nm diameter has been realized via Stöber process and further functionalized using fluoroalkylsilane (FAS-17 molecules to incorporate the fluorinated groups with the silica nanoparticles in an ethanolic solution. The synthesized fluorinated silica nanoparticles have been spin coated on flat aluminum alloy, silicon and glass substrates. Functionalization of silica nanoparticles with fluorinated groups has been confirmed by Fourier Transform Infrared spectroscopy (FTIR by showing the presence of C-F and Si-O-Si bonds. The water contact angles and surface roughness increase with the number of spin-coated thin films layers. The critical size of ~119 nm renders aluminum surface superhydrophobic with three layers of coating using as-prepared nanoparticle suspended solution. On the other hand, seven layers are required for a 50 vol.% diluted solution to achieve superhydrophobicity. In both the cases, water contact angles were more than 150°, contact angle hysteresis was less than 2° having a critical roughness value of ~0.700 µm. The fluorinated silica nanoparticle coated surfaces are also transparent and can be used as paint additives to obtain transparent coatings.

  1. Multilayer optical dielectric coating

    Science.gov (United States)

    Emmett, John L.

    1990-01-01

    A highly damage resistant, multilayer, optical reflective coating includes alternating layers of doped and undoped dielectric material. The doping levels are low enough that there are no distinct interfaces between the doped and undoped layers so that the coating has properties nearly identical to the undoped material. The coating is fabricated at high temperature with plasma-assisted chemical vapor deposition techniques to eliminate defects, reduce energy-absorption sites, and maintain proper chemical stoichiometry. A number of differently-doped layer pairs, each layer having a thickness equal to one-quarter of a predetermined wavelength in the material are combined to form a narrowband reflective coating for a predetermined wavelength. Broadband reflectors are made by using a number of narrowband reflectors, each covering a portion of the broadband.

  2. Inorganic Coatings Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The inorganic Coatings Lab provides expertise to Navy and Joint Service platforms acquisition IPTs to aid in materials and processing choices which balance up-front...

  3. Nanostructured Superhydrophobic Coatings

    Energy Technology Data Exchange (ETDEWEB)

    None

    2009-03-01

    This factsheet describes a research project that deals with the nanostructured superhydrophobic (SH) powders developed at ORNL. This project seeks to (1) improve powder quality; (2) identify binders for plastics, fiberglass, metal (steel being the first priority), wood, and other products such as rubber and shingles; (3) test the coated product for coating quality and durability under operating conditions; and (4) application testing and production of powders in quantity.

  4. Advanced coated particle fuels

    International Nuclear Information System (INIS)

    The coated particle fuel (cpf) has been developed for use in high-temperature gas-cooled reactors, but it may find applications in other types of reactors. In JAERI, besides the development of cpf for High Temperature Engineering Test Reactor, conceptual studies of the cpf applications in actinide burner reactors and space reactors have been made. The conceptual design studies as well as the research and development of advanced coatings, ZrC and TiN, are reviewed. (author)

  5. Hydroxyapatite coatings for biomedical applications

    CERN Document Server

    Zhang, Sam

    2013-01-01

    Hydroxyapatite coatings are of great importance in the biological and biomedical coatings fields, especially in the current era of nanotechnology and bioapplications. With a bonelike structure that promotes osseointegration, hydroxyapatite coating can be applied to otherwise bioinactive implants to make their surface bioactive, thus achieving faster healing and recovery. In addition to applications in orthopedic and dental implants, this coating can also be used in drug delivery. Hydroxyapatite Coatings for Biomedical Applications explores developments in the processing and property characteri

  6. Residual stresses within sprayed coatings

    Institute of Scientific and Technical Information of China (English)

    JIANG Yi; XU Bin-shi; WANG Hai-dou

    2005-01-01

    Some important developments of residual stress researches for coating-based systems were studied. The following topics were included the sources of residual stresses in coatings: error analysis of Stoney's equation in the curvature method used for the measurement of coating residual stress, the modeling of residual stress and some analytical models for predicting the residual stresses in coatings. These topics should provide some important insights for the fail-safe design of the coating-based systems.

  7. Multilayer thermal barrier coating systems

    Science.gov (United States)

    Vance, Steven J.; Goedjen, John G.; Sabol, Stephen M.; Sloan, Kelly M.

    2000-01-01

    The present invention generally describes multilayer thermal barrier coating systems and methods of making the multilayer thermal barrier coating systems. The thermal barrier coating systems comprise a first ceramic layer, a second ceramic layer, a thermally grown oxide layer, a metallic bond coating layer and a substrate. The thermal barrier coating systems have improved high temperature thermal and chemical stability for use in gas turbine applications.

  8. Biocompatibility of Niobium Coatings

    Directory of Open Access Journals (Sweden)

    René Olivares-Navarrete

    2011-09-01

    Full Text Available Niobium coatings deposited by magnetron sputtering were evaluated as a possible surface modification for stainless steel (SS substrates in biomedical implants. The Nb coatings were deposited on 15 mm diameter stainless steel substrates having an average surface roughness of 2 mm. To evaluate the biocompatibility of the coatings three different in vitro tests, using human alveolar bone derived cells, were performed: cellular adhesion, proliferation and viability. Stainless steel substrates and tissue culture plastic were also studied, in order to give comparative information. No toxic response was observed for any of the surfaces, indicating that the Nb coatings act as a biocompatible, bioinert material. Cell morphology was also studied by immune-fluorescence and the results confirmed the healthy state of the cells on the Nb surface. X-ray diffraction analysis of the coating shows that the film is polycrystalline with a body centered cubic structure. The surface composition and corrosion resistance of both the substrate and the Nb coating were also studied by X-ray photoelectron spectroscopy and potentiodynamic tests. Water contact angle measurements showed that the Nb surface is more hydrophobic than the SS substrate.

  9. Coated particle waste form development

    International Nuclear Information System (INIS)

    Coated particle waste forms have been developed as part of the multibarrier concept at Pacific Northwest Laboratory under the Alternative Waste Forms Program for the Department of Energy. Primary efforts were to coat simulated nuclear waste glass marbles and ceramic pellets with low-temperature pyrolytic carbon (LT-PyC) coatings via the process of chemical vapor deposition (CVD). Fluidized bed (FB) coaters, screw agitated coaters (SAC), and rotating tube coaters were used. Coating temperatures were reduced by using catalysts and plasma activation. In general, the LT-PyC coatings did not provide the expected high leach resistance as previously measured for carbon alone. The coatings were friable and often spalled off the substrate. A totally different concept, thermal spray coating, was investigated at PNL as an alternative to CVD coating. Flame spray, wire gun, and plasma gun systems were evaluated using glass, ceramic, and metallic coating materials. Metal plasma spray coatings (Al, Sn, Zn, Pb) provided a two to three orders-of-magnitude increase in chemical durability. Because the aluminum coatings were porous, the superior leach resistance must be due to either a chemical interaction or to a pH buffer effect. Because they are complex, coated waste form processes rank low in process feasibility. Of all the possible coated particle processes, plasma sprayed marbles have the best rating. Carbon coating of pellets by CVD ranked ninth when compared with ten other processes. The plasma-spray-coated marble process ranked sixth out of eleven processes

  10. Coated particle waste form development

    Energy Technology Data Exchange (ETDEWEB)

    Oma, K.H.; Buckwalter, C.Q.; Chick, L.A.

    1981-12-01

    Coated particle waste forms have been developed as part of the multibarrier concept at Pacific Northwest Laboratory under the Alternative Waste Forms Program for the Department of Energy. Primary efforts were to coat simulated nuclear waste glass marbles and ceramic pellets with low-temperature pyrolytic carbon (LT-PyC) coatings via the process of chemical vapor deposition (CVD). Fluidized bed (FB) coaters, screw agitated coaters (SAC), and rotating tube coaters were used. Coating temperatures were reduced by using catalysts and plasma activation. In general, the LT-PyC coatings did not provide the expected high leach resistance as previously measured for carbon alone. The coatings were friable and often spalled off the substrate. A totally different concept, thermal spray coating, was investigated at PNL as an alternative to CVD coating. Flame spray, wire gun, and plasma gun systems were evaluated using glass, ceramic, and metallic coating materials. Metal plasma spray coatings (Al, Sn, Zn, Pb) provided a two to three orders-of-magnitude increase in chemical durability. Because the aluminum coatings were porous, the superior leach resistance must be due to either a chemical interaction or to a pH buffer effect. Because they are complex, coated waste form processes rank low in process feasibility. Of all the possible coated particle processes, plasma sprayed marbles have the best rating. Carbon coating of pellets by CVD ranked ninth when compared with ten other processes. The plasma-spray-coated marble process ranked sixth out of eleven processes.

  11. White coat, patient gown.

    Science.gov (United States)

    Wellbery, Caroline; Chan, Melissa

    2014-12-01

    Much has been written about the symbolic function of the white coat: its implications of purity, its representation of authority and professionalism, and its role in consolidating a medical hierarchy. By contrast, the medical literature has paid almost no attention to the patient gown. In this article, we argue that in order to understand the full implications of the white coat in the doctor-patient relationship, we must also take into account patients' dress, and even undress. We explore contemporary artistic images of white coat and patient gown in order to reveal the power differential in the doctor-patient relationship. Artistic representations capture some of the cultural ambivalence surrounding the use of the white coat, which confers professional status on its wearer, while undermining his or her personal identity. At the other end of the sartorial spectrum, hospital gowns also strip wearers of their identity, but add to this an experience of vulnerability. Although compelling reasons for continuing to wear the white coat in circumscribed settings persist, physicians should be mindful of its hierarchical implications. Ample room remains for improving patients' privacy and dignity by updating the hospital gown. PMID:24687912

  12. Conductive epoxypolyamide coating composition

    Energy Technology Data Exchange (ETDEWEB)

    Mirabeau, M.N.; Rohrbacher, F.

    1991-10-01

    This patent describes a conductive coating composition comprising a film forming binder and pigment in a pigment to binder weight ratio of about 15:100 to 100:100. It comprises 40-70% by weight of an amine component having at least two reactive amine groups selected from the group consisting of an amine, polyamide, polyamido amine resin or mixtures thereof; and 30-60% by weight of an epoxy resin having at least two epoxy groups per resin molecule; wherein the pigment comprises an electrically conductive pigment that comprises silica selected from the group consisting of amorphous silica, a silica containing material or silica coated pigment, the silica being in association with a two- dimensional network of antimony-containing tin oxide crystallites in which the antimony content ranges from about 1-30% by weight of the tin oxide and the composition forms a coating having a surface conductivity of at least 100 Ransburg units.

  13. Preparation of hydrophobic coatings

    Science.gov (United States)

    Branson, Eric D.; Shah, Pratik B.; Singh, Seema; Brinker, C. Jeffrey

    2009-02-03

    A method for preparing a hydrophobic coating by preparing a precursor sol comprising a metal alkoxide, a solvent, a basic catalyst, a fluoroalkyl compound and water, depositing the precursor sol as a film onto a surface, such as a substrate or a pipe, heating, the film and exposing the film to a hydrophobic silane compound to form a hydrophobic coating with a contact angle greater than approximately 150.degree.. The contact angle of the film can be controlled by exposure to ultraviolet radiation to reduce the contact angle and subsequent exposure to a hydrophobic silane compound to increase the contact angle.

  14. Bioceramics for implant coatings

    Directory of Open Access Journals (Sweden)

    Allison A Campbell

    2003-11-01

    Early research in this field focused on understanding the biomechanical properties of metal implants, but recent work has turned toward improving the biological properties of these devices. This has led to the introduction of calcium phosphate (CaP bioceramics as a bioactive interface between the bulk metal impart and the surrounding tissue. The first CaP coatings were produced via vapor phase processes, but more recently solution-based and biomimetic methods have emerged. While each approach has its own intrinsic materials and biological properties, in general CaP coatings promise to improve implant biocompatibility and ultimately implant longevity.

  15. Methods and means for coating paper by film coating

    NARCIS (Netherlands)

    van der Maarel, Marc; Ter Veer, Arend Berend Cornelis; Vrieling-Smit, Annet; Delnoye, Pierre

    2015-01-01

    This invention relates to the field of paper coating, more in particular to means and methods for providing paper with at least one layer of pigment using film coating to obtain a well printable surface. Provided is a method for preparing coated paper comprising the steps of: a) providing a pigmente

  16. Synthesis, structure, and properties of nitrilo-tris(methylenephosphonato)-triaquairon(II) {Fe[µ-NH(CH2PO3H)3](H2O)3}, as an ingredient of anticorrosive protective coatings on the steel surface

    Science.gov (United States)

    Somov, N. V.; Chausov, F. F.; Zakirova, R. M.; Shumilova, M. A.; Aleksandrov, V. A.; Petrov, V. G.

    2015-11-01

    A new non-electrolyte complex of iron(II), {Fe[μ-NH(CH2PO3H)3](H2O)3}, has been synthesized and investigated. The crystallographic characteristics of the complex are as follows: sp. gr. P21/ c , Z = 4, a = 9.2619(3) Å, b = 16.0548(3) Å, c = 9.7570(3) Å, and β = 115.685(4)°. The iron atom is octahedrally coordinated by the three phosphonate oxygen atoms and three water molecules in the meridional configuration. The complex has a coordination polymer structure; each Fe atom closes the eight-membered chelating cycle Fe-O-P-C-N-C-P-O, and one of the phosphorus atoms of this cycle is bound with an iron atom of a neighboring structural unit.

  17. Developing of Anticorrosion and Anti-Wear Composite Coating by Nickel-Aluminum Intermetallic Compound%耐磨耐蚀Ni-Al金属间化合物基复合保护层的研制

    Institute of Scientific and Technical Information of China (English)

    索进平; 冯涤; 骆合力; 崔崑; 钱晓良; 孙尧卿

    2002-01-01

    用粉末冶金法制备WC/Ni3Al复合材料焊条,堆焊于1Cr25Ni20耐热钢的表面,获得的复合材料的耐磨粒磨损性能是45钢的3倍以上,耐硫化腐蚀性高于1Cr25Ni20耐热钢1倍,高于钴基合金Stellite 6约50%.用其制作火电厂燃烧室的喷口钝体,使用寿命较原8Cr26Ni4Mn3大幅度提高,可达到8个月以上.

  18. Application of Cardanol Epoxy Hardener in Anti-Corrosion Coatings for Locomotive Car%腰果油环氧固化剂在铁道车辆防腐涂料中的应用

    Institute of Scientific and Technical Information of China (English)

    曾凡辉; 黎明; 姜其斌; 王永晶

    2008-01-01

    以腰果油改性的酚醛胺环氧同化剂固化环氧防腐涂料,制得了具有优异低温干燥性能和防腐功能的新型铁路车辆防腐涂料.研究了腰果油环氧固化剂对环氧防腐涂料的低温干燥性能和耐盐雾腐蚀性能的影响,并通过DSC和Fr-IR测试对涂料性能进行了表征.结果表明当选用某腰果油环氧固化剂时,和某聚酰胺环氧固化剂相比,在5℃的低温下,防腐涂料环氧基团的开环率由28%提高到84%,涂膜的玻璃化转变温度由60.67℃提高到72.09℃.耐盐雾腐蚀达720 h.

  19. 纳米SiO_2改性输电铁塔防腐蚀涂料%Transmission Tower Anti-corrosion Coatings Modified by SiO2 Nano-particles

    Institute of Scientific and Technical Information of China (English)

    刘江; 谢凤龙; 陈颖敏; 俞立

    2012-01-01

    The agglomeration of nano-SiO2 particles was improved by ultrasonic dispersion and adding dispersing agents to protect the newborn nano-particles.The dispersed nano-SiO2 particles can improve the fluorocarbon finish property.The experimental results indicate that the best time of ultrasonic dispersion was about 30 minutes,and KH570,CH hyper-dispersant and BYK-163 were selected as dispering agents,the performance of KH570 was the best.Both the mechanical properties and the ability to resist chemical reagent of modified fluorocarbon finish were improved and could meet the national standard.%采用超声分散纳米SiO2,同时添加分散剂保护新生纳米SiO2粒子,在一定程度上改善了纳米SiO2团聚的现象,并将分散好的纳米SiO2加入氟碳面漆,用以改性氟碳面漆的性能。选用硅烷偶联剂KH570、CH超分散剂、BYK-163三种分散剂。结果表明,超声分散时间为30min左右,硅烷偶联剂KH570分散纳米SiO2的效果最好;纳米SiO2改性后的氟碳面漆,机械性能与耐化学试剂性能均有了较大改善,各项性能均达到国家标准。

  20. 水工金属结构高压水砂除锈防腐涂装技术研究%Study on high pressure hydraulic sandblasting derusting and anti-corrosive coating technology for hydraulic steel structure

    Institute of Scientific and Technical Information of China (English)

    丁军

    2015-01-01

    高压水砂除锈防腐涂装技术包含高压水砂表面处理技术及带湿耐锈防腐涂装技术.本文从技术原理、技术特点及对比试验等方面对该技术进行了分析研究,解决了干法喷砂除锈的粉尘物理污染和金属喷涂的化学污染,保护了环境和操作人员健康,延长了工程的使用寿命,节省了投资.

  1. Structure, tribological and electrochemical properties of low friction TiAlSiCN/MoSeC coatings

    Energy Technology Data Exchange (ETDEWEB)

    Bondarev, A.V.; Kiryukhantsev-Korneev, Ph.V.; Sheveyko, A.N.; Shtansky, D.V., E-mail: shtansky@shs.misis.ru

    2015-02-01

    counterpart material. This was attributed to the presence of MoSe{sub 2} and free carbon-based phases in the tribological contact. The TiAlSiCN/MoSeC coating with a maximal amount of MoSeC also demonstrated superior tribological characteristics in distilled water (CoF ∼ 0.1) and at moderate temperatures up to 300 °C (CoF < 0.1). The electrochemical tests showed that, in general, doping with MoSeC did not negatively affect the coating electrochemical behavior. On the contrary, the MoSeC phase demonstrated small positive effect on the anti-corrosive properties of TiAlSiCN coatings under small polarizations.

  2. Optical coatings for fiber lasers

    Institute of Scientific and Technical Information of China (English)

    HONG Dong-mei; ZHU Zhen; YUE Wei

    2005-01-01

    Fiber laser is the future development direction for the high energy lasers. This paper describs two kinds of optical coatings for fiber laser, including long and short wave pass filters. The one characteristic of fiber laser coatings lies in that coatings should separate two closely wavelength light including laser pump wavelength (980 nm) and laser irradiation wavelength(1 050~1 100 nm). At the same time, the coatings should have high laser damage threshold.

  3. Carbon coatings for medical implants

    OpenAIRE

    K. Bakowicz-Mitura; P. Couvrat; I. Kotela; P. Louda; D. Batory; J. Grabarczyk

    2007-01-01

    Purpose: In this paper we report in vitro and in vivo results of Nanocrystalline Diamond Coatings whichare used in medicine onto medical implants The very important property of carbon coatings is the protectionliving organism against the metalosis. Different medical implants with complicated shapes are covering byNanocrystalline Diamond Coatings by RF dense plasma CVD.Design/methodology/approach: 1) Material characterizations of deposited coatings have been evaluated by using:Transmission Ele...

  4. Foam coating of filtration media

    OpenAIRE

    Johansson, Mirva

    2015-01-01

    The objective of this thesis was to find out if foam coating could be applied to non-woven filtration media. The goal was to increase collection efficiency without significantly decreasing air permeability. In the theoretical part, foams and their characteristics were the centre of attention. Coating in general and, of course, foam coating were also studied. The empirical part consisted of series of foaming experiments and pilot scale coating experiments. In the foaming experiments differ...

  5. Tribological characterization of selected hard coatings

    OpenAIRE

    Karlsson, Patrik

    2009-01-01

    Hard coatings are often used for protection of tool surfaces due to coating properties like low friction and high wear resistance. Even though many of the hard coatings have been tested for wear, it is important to try new wear test setups to fully understand tribological mechanisms and the potential of hard coatings. Few experiments have been performed with dual-coated systems where the sliding contact surfaces are coated with the same, or different, hard coating. The dual-coated system coul...

  6. TABLET COATING TECHNIQUES: CONCEPTS AND RECENT TRENDS

    Directory of Open Access Journals (Sweden)

    Gupta Ankit

    2012-09-01

    Full Text Available Tablet coating is a common pharmaceutical technique of applying a thin polymer-based film to a tablet or a granule containing active pharmaceutical ingredients (APIs. Solid dosage forms are coated for a number of reasons, the most important of which is controlling the release profiles. The amount of coating on the surface of a tablet is critical to the effectiveness of the oral dosage form. Tablets are usually coated in horizontal rotating pans with the coating solution sprayed onto the free surface of the tablet bed. The advantages of tablet coating are taste masking, odour masking, physical and chemical protection, protects the drug from the gastric environment etc. There are various techniques for tablet coating such as sugar coating, film coating, and enteric coating. Recent trends in pharmaceutical technologies are the development of coating methods which overcomes the various disadvantages associated with solvent based coatings. In these latest technologies coating materials are directly coated onto the surface of solid dosage forms without using any solvent. Various solventless coatings are available such as electrostatic dry coating, magnetically assisted impaction coating, compression coating, hot melt coating, powder coating, and supercritical fluid coating. Supercell Coating Technology is a revolutionary tablet coating that accurately deposits controlled amounts of coating materials on tablets even if they are extremely hygroscopic or friable. Magnetically assisted impaction coating, electrostatic dry coating in solventless coatings, aqueous film coating and Supercell coating technology are also available recent technique of coating. An ideal tablet should be free from any visual defect or functional defect. The advancements and innovations in tablet manufacture have not decreased the problems, often encountered in the production, instead have increased the problems, mainly because of the complexities of tablet presses; and/or the

  7. Niobium coating techniques

    CERN Document Server

    Calatroni, S

    2008-01-01

    We will give a historical overview of the niobium on copper sputtering technology for RF cavities and discuss the main advantages and disadvantages with respect to bulk niobium cavities. Some highlights of the present understanding will be given and some recent developments in the coating technology will be discussed.

  8. Coatings for transport industry

    Directory of Open Access Journals (Sweden)

    Krzysztof LUKASZKOWICZ

    2014-09-01

    Full Text Available The investigations concerned structural analysis, as well as mechanical properties and wear resistant of MeN/DLC double-layer coating deposited by hybrid PVD/PACVD method. In sliding dry friction conditions, after the break-in time, the friction coefficient for the investigated elements is set in the range between 0.03-0.06.

  9. Rheology of Coating Materials and Their Coating Characteristics

    Science.gov (United States)

    Grabsch, C.; Grüner, S.; Otto, F.; Sommer, K.

    2008-07-01

    Lots of particles used in the pharmaceutical and the food industry are coated to protect the core material. But almost no investigations about the coating material behavior do exist. In this study the focus was on the rheological material properties of fat based coating materials. Rotational shear experiments to determine the viscosity of a material were compared to oscillatory shear tests to get information about the vicoelastic behavior of the coating materials. At the liquid state the viscosity and the viscoelastic properties showed a good analogy. The viscoelastic properties of the solid coating materials yielded differences between materials that have the same properties at the liquid state.

  10. Active coatings technologies for tailorable military coating systems

    Science.gov (United States)

    Zunino, J. L., III

    2007-04-01

    The main objective of the U.S. Army's Active Coatings Technologies Program is to develop technologies that can be used in combination to tailor coatings for utilization on Army Materiel. The Active Coatings Technologies Program, ACT, is divided into several thrusts, including the Smart Coatings Materiel Program, Munitions Coatings Technologies, Active Sensor packages, Systems Health Monitoring, Novel Technology Development, as well as other advanced technologies. The goal of the ACT Program is to conduct research leading to the development of multiple coatings systems for use on various military platforms, incorporating unique properties such as self repair, selective removal, corrosion resistance, sensing, ability to modify coatings' physical properties, colorizing, and alerting logistics staff when tanks or weaponry require more extensive repair. A partnership between the U.S. Army Corrosion Office at Picatinny Arsenal, NJ along with researchers at the New Jersey Institute of Technology, NJ, Clemson University, SC, University of New Hampshire, NH, and University of Massachusetts (Lowell), MA, are developing the next generation of Smart Coatings Materiel via novel technologies such as nanotechnology, Micro-electromechanical Systems (MEMS), meta-materials, flexible electronics, electrochromics, electroluminescence, etc. This paper will provide the reader with an overview of the Active Coatings Technologies Program, including an update of the on-going Smart Coatings Materiel Program, its progress thus far, description of the prototype Smart Coatings Systems and research tasks as well as future nanotechnology concepts, and applications for the Department of Defense.

  11. Ceramic coating on ceramic with metallic bond coating

    Science.gov (United States)

    Kishitake, K.; Era, H.; Otsubo, F.; Sonoda, T.

    1997-09-01

    The change in structure and adhesion strength of the interface by heating in air has been investigated for a plasma- sprayed alumina coating on a ceramic substrate with a 50Ni- 50Cr alloy bond coating. A veined structure composed of NiO, NiCr 2O4, and NiAl2O4 oxides grew from the bond coating into cracks or pores in the top coating and the alumina substrate after heating at 1273 K for 20 h in air. The NiAl2O4 spinel may have formed by the oxidization of nickel, which subsequently reacted with the alumina coating or the substrate. The mechanism of the penetration of the spinel oxides into the cracks or pores is not clear. The adhesion strength of the coating is increased to about 15 MPa after heating at 1273 K for 20 h in air, compared to an as- sprayed coating strength of only 1.5 MPa.

  12. Flame-coating method and flame-coating device

    International Nuclear Information System (INIS)

    The method and the device of the present invention improve the quality and operation efficiency of coating applied to corner portions of under water reactor structural components of a nuclear reactor. Namely, powders for the flame-coating are provided with ferromagnetic property in a step of forming coating films to underwater structural members by an underwater flame-coating method in a nuclear reactor. A flow of plasma arc can be bent by applying magnetic fields to the flame-coating plasma arc. Accordingly, coatings can be applied to corner portions particularly to pad-weld portions among welded members. Further, the flame-coating can be applied while being conformed to the shape of the place where a surface layer is formed, by controlling the extension of the plasma arc by making the shape of the plasma arc irradiated on the surface of a work rectangular, elliptic or linear. (I.S.)

  13. Infrared optical coatings in SITP

    Institute of Scientific and Technical Information of China (English)

    LIU Ding-quan; ZHANG Feng-shan

    2005-01-01

    Infrared optical coatings in SITP (Shanghai Institute of Technical Physics) mainly cover the spectrum range from 0.7 μm to 15 μm, and visible and near-UV range are also been included. The coatings are mainly used for metal-reflectance mirrors, Anti-reflection(AR) lens and windows, filters, and dichroic beam splitters. Coatings passed some dependability tests. These optical coated devices usually consist in a remote observing instrument. Most coating materials are commercial products. And one kind of special material PbTe is made by ourselves. Some main results of our research department are reported.

  14. Graphite coating of nuclear fuels

    International Nuclear Information System (INIS)

    This paper gives an account of work conducted on graphite coating of (1) zircaloy fuel tubes for CANDU type power reactors and (2) stainless steel bearing plates for S3F vault structure commissioned at Tarapur for storage of radioactive waste. Graphite has been chosen as a coating material because it is not only an excellent lubricating material but also can withstand severe radiation from nuclear fuel or radioactive waste up to fairly high temperatures. The paper first describes in detail the equipments and experimental procedure standardised to achieve an adherent graphite coating of 5 to 9 μm thickness by using alcohol based suspension of graphite. Graphite coated tubes were evaluated by subjecting it to various destructive and nondestructive testing. Thousands of fuel tubes were coated so far and loaded in RAPP-2 for studying their inpile behaviour. Finally a flowsheet is presented to achieve the graphite coating on fuel tubes as per specifications. The second part of the paper deals with the various techniques examined to obtain the graphite coating on 450 mm square stainless steel plates with alcohol based graphite suspension. An unique spray coating procedure involving both graphite suspension and lacquor was evolved for carrying out the coating operation at site. Co-efficient of friction between graphite coated SS plates was found to be as low as 6.77 per cent. A batch of 280 SS bearing plates were coated with graphite and utilised for commissioning the vault structure at Tarapur. (author). 5 figures

  15. Methods for Coating Particulate Material

    Science.gov (United States)

    Littman, Howard (Inventor); Plawsky, Joel L. (Inventor); Paccione, John D. (Inventor)

    2013-01-01

    Methods and apparatus for coating particulate material are provided. The apparatus includes a vessel having a top and a bottom, a vertically extending conduit having an inlet in the vessel and an outlet outside of the vessel, a first fluid inlet in the bottom of the vessel for introducing a transfer fluid, a second fluid inlet in the bottom of the vessel for introducing a coating fluid, and a fluid outlet from the vessel. The method includes steps of agitating a material, contacting the material with a coating material, and drying the coating material to produce a coated material. The invention may be adapted to coat aerogel beads, among other materials. A coated aerogel bead and an aerogel-based insulation material are also disclosed.

  16. BIODEGRADABLE COATING FROM AGATHIS ALBA

    Directory of Open Access Journals (Sweden)

    NORYAWATI MULYONO

    2012-11-01

    Full Text Available The adhesive property of copal makes it as a potential coating onto aluminum foil to replace polyethylene. This research aimed to develop copal-based coating. The coating was prepared by extracting the copal in ethyl acetate and dipping the aluminium foil in ethyl acetate soluble extract of copal. The characterization of coating included its thickness, weight, thermal and chemical resistance, and biodegradation. The results showed that the coating thickness and weight increased as the copal concentration and dipping frequency increased. Thermal resistance test showed that the coating melted after being heated at 110°C for 30 min. Copal-based coating wasresistant to acidic solution (pH 4.0, water, and coconut oil, but was deteriorated in detergent 1% (w/v and basic solution (pH 10.0. Biodegradability test using Pseudomonas aeruginosa showed weight reduction of 76.82% in 30 days.

  17. QUALITY IN METALLIZED COATING APPLICATIONS

    Directory of Open Access Journals (Sweden)

    Bülent Eker

    2010-12-01

    Full Text Available Metalized coating is attained by atomizing the coating metal by melting with proper gas (propane, acetylene or others and oxygen compound and then spraying it with compressed air all over the surface to be coated. Metallization in the application is the process of vaporization of the needed metal with tungsten in vacuumed media. This system among the PVD Coating groups is known as Evaporation Coating all through the world. Although the very fine metal layer that condenses over the product to be coated varies from sector to sector; it is generally used with aesthetic and decorative aims. The surface of the part to be coated is cleaned off the effects such as dirt, dust and oils etc. this cleaning method varies according to the size, shape and material of the piece to be coated. Surface cleaning before coating is very important in the sense of coating life, quality and strength. Otherwise, expected yield cannot be attained from the metalized and corrosion start can be observed shortly due to remnants on the places which are not thoroughly cleaned. Since metallization is a vaporization method; it is ionized by melting on all places which are in high-vacuumed. But there occurs an adsorption problem on some plastic types, therefore a smooth coating is attained applying an adherence through interlayer on these products before coating or with corona application. In food packaging sector metalized coated products are used because of their barrier feature towards light, water vapor, oxygen and other gases. This method of packaging is widely used in such kinds of sectors due to being most economical in packaging sector. For example; food packaging sector which holds a great place in flexible packaging group uses metalized coating system due to their barrier feature of metalized film with the aim of preventing oxidation of food products, decreasing the need of protective addition agent and extending the shell-life. Moreover cosmetic packaging group and

  18. Coat proteins isolated from clathrin coated vesicles can assemble into coated pits

    OpenAIRE

    1989-01-01

    Isolated human fibroblast plasma membranes that were attached by their extracellular surface to a solid substratum contained numerous clathrin coated pits that could be removed with a high pH buffer (Moore, M.S., D.T. Mahaffey, F.M. Brodsky, and R.G.W. Anderson. 1987. Science [Wash. DC]. 236:558-563). When these membranes were incubated with coat proteins extracted from purified bovine coated vesicles, new coated pits formed that were indistinguishable from native coated pits. Assembly was de...

  19. Superelastic Orthopedic Implant Coatings

    Science.gov (United States)

    Fournier, Eric; Devaney, Robert; Palmer, Matthew; Kramer, Joshua; El Khaja, Ragheb; Fonte, Matthew

    2014-07-01

    The demand for hip and knee replacement surgery is substantial and growing. Unfortunately, most joint replacement surgeries will fail within 10-25 years, thereby requiring an arduous, painful, and expensive revision surgery. To address this issue, a novel orthopedic implant coating material ("eXalt") has been developed. eXalt is comprised of super elastic nitinol wire that is knit into a three-dimensional spacer fabric structure. eXalt expands in vivo to conform to the implantation site and is porous to allow for bone ingrowth. The safety and efficacy of eXalt were evaluated through structural analysis, mechanical testing, and a rabbit implantation model. The results demonstrate that eXalt meets or exceeds the performance of current coating technologies with reduced micromotion, improved osseointegration, and stronger implant fixation in vivo.

  20. Acrylic purification and coatings

    CERN Document Server

    ,

    2012-01-01

    Radon (Rn) and its decay daughters are a well-known source of background in direct WIMP detection experiments, as either a Rn decay daughter or an alpha particle emitted from a thin inner surface layer of a detector could produce a WIMP-like signal. Different surface treatment and cleaning techniques have been employed in the past to remove this type of contamination. A new method of dealing with the problem has been proposed and used for a prototype acrylic DEAP-1 detector. Inner surfaces of the detector were coated with a layer of ultra pure acrylic, meant to shield the active volume from alphas and recoiling nuclei. An acrylic purification technique and two coating techniques are described: a solvent-borne (tested on DEAP-1) and solvent-less (being developed for the full scale DEAP-3600 detector).

  1. Thermal barrier coating materials

    OpenAIRE

    Clarke, David R.; Simon R. Phillpot

    2005-01-01

    Improved thermal barrier coatings (TBCs) will enable future gas turbines to operate at higher gas temperatures. Considerable effort is being invested, therefore, in identifying new materials with even better performance than the current industry standard, yttria-stabilized zirconia (YSZ). We review recent progress and suggest that an integrated strategy of experiment, intuitive arguments based on crystallography, and simulation may lead most rapidly to the development of new TBC materials.

  2. New casting coatings

    International Nuclear Information System (INIS)

    In this project the results of the researches about the influence of the four types of ceramic coatings of the evaporating patterns (on the basis of talc, mullite, zircon and cordierite) on the talc of the Lost Foam process and the castings quality are presented. For the valid evaluation of the results, some parallel examinations of the quality of castings obtained by casting in sand were carried out. (Original)

  3. Environmentally regulated aerospace coatings

    Science.gov (United States)

    Morris, Virginia L.

    1995-01-01

    Aerospace coatings represent a complex technology which must meet stringent performance requirements in the protection of aerospace vehicles. Topcoats and primers are used, primarily, to protect the structural elements of the air vehicle from exposure to and subsequent degradation by environmental elements. There are also many coatings which perform special functions, i.e., chafing resistance, rain erosion resistance, radiation and electric effects, fuel tank coatings, maskants, wire and fastener coatings. The scheduled promulgation of federal environmental regulations for aerospace manufacture and rework materials and processes will regulate the emissions of photochemically reactive precursors to smog and air toxics. Aerospace organizations will be required to identify, qualify and implement less polluting materials. The elimination of ozone depleting chemicals (ODC's) and implementation of pollution prevention requirements are added constraints which must be addressed concurrently. The broad categories of operations affected are the manufacture, operation, maintenance, and repair of military, commercial, general aviation, and space vehicles. The federal aerospace regulations were developed around the precept that technology had to be available to support the reduction of organic and air toxic emissions, i.e., the regulations cannot be technology forcing. In many cases, the regulations which are currently in effect in the South Coast Air Quality Management District (SCAQMD), located in Southern California, were used as the baseline for the federal regulations. This paper addresses strategies used by Southern California aerospace organizations to cope with these regulatory impacts on aerospace productions programs. All of these regulatory changes are scheduled for implementation in 1993 and 1994, with varying compliance dates established.

  4. Biomimetic implant coatings.

    Science.gov (United States)

    Eisenbarth, E; Velten, D; Breme, J

    2007-02-01

    Biomaterials and tissue engineering technologies are becoming increasingly important in biomedical practice, particularly as the population ages. Cellular responses depend on topographical properties of the biomaterial at the nanometer scale. Structures on biomaterial surfaces are used as powerful tools to influence or even control interactions between implants and the biological system [; ]. The influence of nanometer sized surface structures on osteoblastlike cell interactions was tested with niobium oxide coatings on polished titanium slices (cp-Ti grade 2). The aim of the study was to investigate the influence of nanoscopic surface structures on osteoblast interactions in order to support collagen I production and cell adhesion. The coatings were done by means of the sol-gel process. The surface structure was adjusted by annealing of the metaloxide ceramic coatings due to temperature depended crystal growth. The applied annealing temperatures were 450, 550 and 700 degrees C for 1 h, corresponding to Ra-numbers of 7, 15 and 40 nm. The surfaces were characterized by means of AFM, DTA/TG, diffractometry and white light interferometry. The cell reactions were investigated concerning adhesion kinetics, migration, spreading, cell adhesion, and collagen I synthesis. The smooth surface (Ra=7 nm) resulted in the fastest cell anchorage and cell migration. The closest cell adhesion was reached with the surface structure of Ra=15 nm. The roughest surface (Ra=40 nm) impedes the cell migration as well as a proper spreading of the cells. The best results concerning cell adhesion and spreading was reached with an intermediate surface roughness of Ra=15 nm of the niobium oxide coating on cp-titanium slices. PMID:16828342

  5. New Anti-Corrosion Method for Compressor Motor Stator by Using Ion-Membrane%离子膜用于压缩机电机定子的防腐新途径

    Institute of Scientific and Technical Information of China (English)

    马汉堡

    2012-01-01

    The continuous tunnel furnace flange processing is not efficient in solving the corrosion problem for compressor motor stator. The self-catalyzed inorganic ion-membrane changed the traditional processing of decades. Its excellent corrosion resistance was proved by RoHS solubility experiment of R134a and R600a. It provides a new approach of anti-corrosion application for compressor motor stator.%压缩机用电机的定子通常采用隧道炉发兰工艺来解决防腐问题,但是效果不理想.自催化无机离子膜的问世,打破了数十年的传统工艺.自催化无机离子膜不仅具备优越的防腐性能,而且经得起R134a和R600a的RoHS相溶性试验,从而开辟了压缩机用电机定子防腐应用的新途径.

  6. Edison's vacuum coating patents

    International Nuclear Information System (INIS)

    Among the over one thousand patents bearing Thomas A. Edison's name are several for vacuum coating processes including chemical vapor deposition, evaporation, and sputter deposition. Beginning in 1880 Edison applied for patents that described carbon deposition processes that would now be called pyrolytic chemical vapor deposition. In 1884 Edison applied for a patent (granted in 1894) that described coating by evaporation in a vacuum by direct resistance heating or arc heating using a continuous current. Edison called the process 'electro vacuous deposition'. He prophetically wrote, 'the uses of the invention are almost infinite'. Edison also employed sputter deposition and in 1900 applied for a patent on a 'Process of Coating Phonograph Records'. Issued in 1902, the patent describes using a 'silent or brush electrical discharge' produced by an induction coil. The National Phonograph Company, one of Edison's many enterprises, used the sputtering process to deposit a thin layer of gold on wax phonograph cylinder masters that could then be electroplated to form molds to mass produce celluloid duplicates. The method was used for 20 years, from 1901 to 1921. It enabled the reproduction of cylinder grooves less than 0.001 in. deep at a density of 200 grooves per in. From 1913 to 1921, 10-in.-diameter Edison Diamond Disc phonograph records were made using the same method. Sputtering was abandoned in 1927, as it could not be scaled up to produce the 12 in. disks that were then introduced

  7. for zeolite coating

    Directory of Open Access Journals (Sweden)

    Carlos Renato Rambo

    2006-01-01

    Full Text Available Biotemplating is the processing of microcellular ceramics by reproduction of natural morphologies, where the microstructural features of the biotemplate are maintained in the biomorphic ceramic. Different biotemplates with distinct pore anatomies were used to produce biomorphic supports for the zeolite coating: wood, cardboard, sea-sponge and sisal. The biomorphic ceramics were produced by distinguished processing routes: Al-gas infiltration-reaction, liquid-metal infiltration, dip-coating and sol-gel synthesis, in order to produce nitrides, carbides and oxides, depending on the processing conditions. The zeolite coating was performed by hydrothermal growth of MFI-type (Silicalite-1 and ZSM-5 zeolite crystals onto the internal pore walls of the biomorphic templates. The final biomorphic ceramic-zeolite composites were physically characterized, evaluated in terms of their gas adsorption capabilities and correlated to their microstructure and specific pore anatomy. The combination of the properties of the biomorphic ceramics with the adsorption properties of zeolites results in materials with distinct properties as potential candidates for adsorption and catalytic applications due to their characteristic porosity, molecular sieving capabilities and high thermo-mechanical strength.

  8. Surface coating of plastics

    International Nuclear Information System (INIS)

    Electron beam hardening technology has been used mainly for the cross-linking reaction of plastic materials, but recently attention has been paid to the easiness of handling due to the reduction of equipment size and as the countermeasures for preventing atmospheric pollution caused by solvent type paints, Particularly the authors notices the excellent surface properties of electron beam-hardened coatings themselves, and advanced the research and development as one means to give functions to plastic films. In this paper, the transcription foil films having hardness and blur-preventing films are reported. The transcription process for the transcription foils on which hard coating is applied beforehand is shown. The electron beam hardening hard coating was provided next to a supporting film, and its material was polymer or oligomer/polyfunctional monomer/additive. As a primer layer, acrylic polymer was used. The procedure of making transcription foils is explained, and it is important to form uniform, smooth films. If the formation of water drops on surfaces can be prevented, blur does not arise. By heightening the hydrophilicity of material surfaces with electron beam, it may be done. By the selection of the irradiation amount of electron beam and materials, the balance must be maintained. (K.I.)

  9. Coating and curing apparatus and methods

    Energy Technology Data Exchange (ETDEWEB)

    Brophy, Brenor L.; Gonsalves, Peter R.; Maghsoodi, Sina; Colson, Thomas E.; Yang, Yu S.; Abrams, Ze' ev R.

    2016-04-19

    Disclosed is a coating apparatus including flow coating and roll-coating that may be used for uniform sol-gel coating of substrates such as glass, solar panels, windows or part of an electronic display. Also disclosed are methods for substrate preparation, flow coating and roll coating. Lastly, systems and methods for curing sol-gel coatings deposited onto the surface of glass substrates using high temperature air-knives, infrared emitters and direct heat applicators are disclosed.

  10. Coating and curing apparatus and methods

    Science.gov (United States)

    Brophy, Brenor L; Maghsoodi, Sina; Neyman, Patrick J; Gonsalves, Peter R; Hirsch, Jeffrey G; Yang, Yu S

    2015-02-24

    Disclosed are coating apparatus including flow coating and roll-coating that may be used for uniform sol-gel coating of substrates such as glass, solar panels, windows or part of an electronic display. Also disclosed are methods for substrate preparation, flow coating and roll coating. Lastly systems and methods for skin curing sol-gel coatings deposited onto the surface of glass substrates using a high temperature air-knife are disclosed.

  11. High-temperature protective coatings on superalloys

    Institute of Scientific and Technical Information of China (English)

    刘培生; 梁开明; 周宏余

    2002-01-01

    Protective coatings are essential for superalloys to serve as blades of gas turb ines at high temperatures, and they primarily include aluminide coating, MCrAlY overlay coating, thermal barrier coating and microcrystalline coating. In this paper, all these high-temperature coatings are reviewed as well as their preparing techniques. Based on the most application and the main failure way, the importance is then presented for further deepgoing study on the high-temperature oxidation law of aluminide coatings.

  12. Lotus Dust Mitigation Coating and Molecular Adsorber Coating

    Science.gov (United States)

    O'Connor, Kenneth M.; Abraham, Nithin S.

    2015-01-01

    NASA Goddard Space Flight Center has developed two unique coating formulations that will keep surfaces clean and sanitary and contain contaminants.The Lotus Dust Mitigation Coating, modeled after the self-cleaning, water-repellant lotus leaf, disallows buildup of dust, dirt, water, and more on surfaces. This coating, has been successfully tested on painted, aluminum, glass, silica, and some composite surfaces, could aid in keeping medical assets clean.The Molecular Adsorber Coating is a zeolite-based, sprayable molecular adsorber coating, designed to prevent outgassing in materials in vacuums. The coating works well to adsorb volatiles and contaminates in manufacturing and processing, such as in pharmaceutical production. The addition of a biocide would also aid in controlling bacteria levels.

  13. Dense protective coatings, methods for their preparation and coated articles

    Energy Technology Data Exchange (ETDEWEB)

    Tulyani, Sonia; Bhatia, Tania; Smeggil, John G.

    2015-12-29

    A method for depositing a protective coating on a complex shaped substrate includes the steps of: (1) dipping a complex shaped substrate into a slurry to form a base coat thereon, the slurry comprising an aqueous solution, at least one refractory metal oxide, and at least one transient fluid additive present in an amount of about 0.1 percent to 10 percent by weight of the slurry; (2) curing the dipped substrate; (3) dipping the substrate into a precursor solution to form a top barrier coat thereon; and (4) heat treating the dipped, cured substrate to form a protective coating.

  14. Nanoparticle/Polymer Nanocomposite Bond Coat or Coating

    Science.gov (United States)

    Miller, Sandi G.

    2011-01-01

    This innovation addresses the problem of coatings (meant to reduce gas permeation) applied to polymer matrix composites spalling off in service due to incompatibility with the polymer matrix. A bond coat/coating has been created that uses chemically functionalized nanoparticles (either clay or graphene) to create a barrier film that bonds well to the matrix resin, and provides an outstanding barrier to gas permeation. There is interest in applying clay nanoparticles as a coating/bond coat to a polymer matrix composite. Often, nanoclays are chemically functionalized with an organic compound intended to facilitate dispersion of the clay in a matrix. That organic modifier generally degrades at the processing temperature of many high-temperature polymers, rendering the clay useless as a nano-additive to high-temperature polymers. However, this innovation includes the use of organic compounds compatible with hightemperature polymer matrix, and is suitable for nanoclay functionalization, the preparation of that clay into a coating/bondcoat for high-temperature polymers, the use of the clay as a coating for composites that do not have a hightemperature requirement, and a comparable approach to the preparation of graphene coatings/bond coats for polymer matrix composites.

  15. Special coatings for the LHC

    CERN Document Server

    Calatroni, S

    2004-01-01

    Several LHC components require a thin film coating. These coatings fall in two main categories, namely NEG coatings to improve the vacuum behaviour of chambers or conductive coatings to decrease the surface impedance of components. Examples of the first category are the intersection vacuum chambers of the different experiments, where the required vacuum can be obtained only with a NEG coating because of the large distance of the nearest pumping station. The graphite jaws of collimators are an example of the second category. In this case the high impedance of graphite must be decreased by a thin copper coating. These and other cases will be illustrated both with respect to the machine requirements and to the production programme.

  16. Article Including Environmental Barrier Coating System

    Science.gov (United States)

    Lee, Kang N. (Inventor)

    2015-01-01

    An enhanced environmental barrier coating for a silicon containing substrate. The enhanced barrier coating may include a bond coat doped with at least one of an alkali metal oxide and an alkali earth metal oxide. The enhanced barrier coating may include a composite mullite bond coat including BSAS and another distinct second phase oxide applied over said surface.

  17. Coatings for fusion reactor environments

    International Nuclear Information System (INIS)

    The internal surfaces of a tokamak fusion reactor control the impurity injection and gas recycling into the fusion plasma. Coating of internal surfaces may provide a desirable and possibly necessary design flexibility for achieving the temperatures, ion densities and containment times necessary for net energy production from fusion reactions to take place. In this paper the reactor environments seen by various componentare reviewed along with possible materials responses. Characteristics of coating-substrate systems, important to fusion applications, are delineated and the present status of coating development for fusion applications is reviewed. Coating development for fusion applications is just beginning and poses a unique and important challenge for materials development

  18. Thermoplastic coating of carbon fibers

    Science.gov (United States)

    Edie, D. D.; Lickfield, G. C.; Allen, L. E.; Mccollum, J. R.

    1989-01-01

    A continuous powder coating system was developed for coating carbon fiber with LaRC-TPI (Langley Research Center-Thermoplastic Polyimide), a high-temperature thermoplastic polymide invented by NASA-Langley. The coating line developed used a pneumatic fiber spreader to separate the individual fibers. The polymer was applied within a recirculating powder coating chamber then melted using a combination of direct electrical resistance and convective heating to make it adhere to the fiber tow. The tension and speed of the line were controlled with a dancer arm and an electrically driven fiber wind-up and wind-off. The effects of heating during the coating process on the flexibility of the prepreg produced were investigated. The uniformity with which the fiber tow could be coated with polymer also was examined. Composite specimens were fabricated from the prepreg and tested to determine optimum process conditions. The study showed that a very uniform and flexible prepeg with up to 50 percent by volume polymer could be produced with this powder coating system. The coating line minimized powder loss and produced prepeg in lengths of up to 300 m. The fiber spreading was found to have a major effect on the coating uniformity and flexibility. Though test results showed low composite tensile strengths, analysis of fracture surfaces under scanning electron microscope indicated that fiber/matrix adhesion was adequate.

  19. Decontamination and coating of lead

    International Nuclear Information System (INIS)

    Technology is being developed to decontaminate lead used in shielding applications in contaminated environments for recycle as shieldings. Technology is also being developed to coat either decontaminated lead or new lead before it is used in contaminated environments. The surface of the coating is expected to be much easier to decontaminate than the original lead surface. If contamination becomes severely embedded in the coating and cannot be removed, it can be easily cut with a knife and removed from the lead. The used coating can be disposed of as radioactive (hot hazardous) waste. The lead can then be recoated for further use as a shielding material

  20. Ceramic electrolyte coating and methods

    Science.gov (United States)

    Seabaugh, Matthew M.; Swartz, Scott L.; Dawson, William J.; McCormick, Buddy E.

    2007-08-28

    Aqueous coating slurries useful in depositing a dense coating of a ceramic electrolyte material (e.g., yttrium-stabilized zirconia) onto a porous substrate of a ceramic electrode material (e.g., lanthanum strontium manganite or nickel/zirconia) and processes for preparing an aqueous suspension of a ceramic electrolyte material and an aqueous spray coating slurry including a ceramic electrolyte material. The invention also includes processes for depositing an aqueous spray coating slurry including a ceramic electrolyte material onto pre-sintered, partially sintered, and unsintered ceramic substrates and products made by this process.