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Sample records for auto-catalytic electroless plating

  1. Electroless Plating on Plastic Induced by Selective Laser Activation

    DEFF Research Database (Denmark)

    Zhang, Yang; Tang, Peter Torben; Hansen, Hans Nørgaard;

    2009-01-01

    This paper presents a new method for selective micro metallization of polymers. A Nd:YAG laser is employed to draw patterns on polymer surfaces that are submerged in a liquid (usually water). After subsequent activation with palladium chloride and followed by auto-catalytic electroless plating, c...

  2. Hydrogen Recombination Rates of Plate-type Passive Auto-catalytic Recombiner

    International Nuclear Information System (INIS)

    The hydrogen mitigation system may include igniters, passive autocatalytic recombiner (PAR), and venting or dilution system. Recently PAR is commonly used as a main component of HMS in a NPP containment because of its passive nature. PARs are categorized by the shape and material of catalytic surface. Catalytic surface coated by platinum is mostly used for the hydrogen recombiners. The shapes of the catalytic surface can be grouped into plate type, honeycomb type and porous media type. Among them, the plate-type PAR is well tested by many experiments. PAR performance analysis can be approached by a multi-scale method which is composed of micro, meso and macro scales. The criterion of the scaling is the ratio of thickness of boundary layer developed on a catalytic surface to representative length of a computational domain. Mass diffusion in the boundary layer must be resolved in the micro scale analysis. In a lumped parameter (LP) analysis using a system code such as MAAP or MELCOR, the chamber of the PAR is much smaller than a computational node. The hydrogen depletion by a PAR is modeled as a source of mass and energy conservation equations. Te catalytic surface reaction of hydrogen must be modeled by a volume-averaged correlation. In this study, a micro scale analysis method is developed using libraries in OpenFOAM to evaluate a hydrogen depletion rate depending on parameters such as size and number of plates and plate arrangement. The analysis code is validated by simulating REKO-3 experiment. And hydrogen depletion analysis is conducted by changing the plate arrangement as a trial of the performance enhancement of a PAR. In this study, a numerical code for an analysis of a PAR performance in a micro scale has been developed by using OpenFOAM libraries. The physical and numerical models were validated by simulating the REKO-3 experiment. As a try to enhance the performance of the plate-type PAR, it was proposed to apply a staggered two-layer arrangement of the

  3. Hydrogen Recombination Rates of Plate-type Passive Auto-catalytic Recombiner

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jongtae; Hong, Seong-Wan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Gun Hong [Kyungwon E-C Co., Seongnam (Korea, Republic of)

    2014-10-15

    The hydrogen mitigation system may include igniters, passive autocatalytic recombiner (PAR), and venting or dilution system. Recently PAR is commonly used as a main component of HMS in a NPP containment because of its passive nature. PARs are categorized by the shape and material of catalytic surface. Catalytic surface coated by platinum is mostly used for the hydrogen recombiners. The shapes of the catalytic surface can be grouped into plate type, honeycomb type and porous media type. Among them, the plate-type PAR is well tested by many experiments. PAR performance analysis can be approached by a multi-scale method which is composed of micro, meso and macro scales. The criterion of the scaling is the ratio of thickness of boundary layer developed on a catalytic surface to representative length of a computational domain. Mass diffusion in the boundary layer must be resolved in the micro scale analysis. In a lumped parameter (LP) analysis using a system code such as MAAP or MELCOR, the chamber of the PAR is much smaller than a computational node. The hydrogen depletion by a PAR is modeled as a source of mass and energy conservation equations. Te catalytic surface reaction of hydrogen must be modeled by a volume-averaged correlation. In this study, a micro scale analysis method is developed using libraries in OpenFOAM to evaluate a hydrogen depletion rate depending on parameters such as size and number of plates and plate arrangement. The analysis code is validated by simulating REKO-3 experiment. And hydrogen depletion analysis is conducted by changing the plate arrangement as a trial of the performance enhancement of a PAR. In this study, a numerical code for an analysis of a PAR performance in a micro scale has been developed by using OpenFOAM libraries. The physical and numerical models were validated by simulating the REKO-3 experiment. As a try to enhance the performance of the plate-type PAR, it was proposed to apply a staggered two-layer arrangement of the

  4. LASER INDUCED SELECTIVE ACTIVATION UTILIZING AUTO-CATALYTIC ELECTROLESS PLATING ON POLYMER SURFACE

    DEFF Research Database (Denmark)

    Zhang, Yang; Nielsen, Jakob Skov; Tang, Peter Torben;

    2009-01-01

    . Characterization of the deposited copper layer was used to select and improve laser parameters. Several types of polymers with different melting points were used as substrate. Using the above mentioned laser treatment, standard grades of thermoplastic materials such as ABS, SAN, PE, PC and others have been...

  5. Study of electroless nickel plating on PerFactoryTM rapid prototype model

    Directory of Open Access Journals (Sweden)

    J.C. Rajaguru

    2012-12-01

    Full Text Available This paper presents an investigation of electroless nickel plating on PerFactoryTM rapid prototype model built on PerFactoryTM R05 material. PerFactoryTM R05 is acrylic based photo sensitive resin. It is a popular material in rapid prototyping using PerFactoryTM method which employs addictive manufacturing technique to build prototypes for visual inspection, assembly etc. Metallization of such a prototype can extend the application envelop of the rapid prototyping technique as they can be used in many functional applications. Unlike the electroless nickel plating on metal substrate, the process on acrylic resin substrate is not auto-catalytic. Hence, etching and activation are necessary for initiating the process. The final coating is then investigated using scanning electron microscope (SEM together with energy dispersive spectroscopy (EDS and x-ray diffraction (XRD analysis to identify the morphology and structure of the coating. The SEM & EDS analysis on surface and chemical composition of model surface after each preliminary surface treatment are also presented. Finally the layer is tested on Vickers micro hardness tester.

  6. Electroless nickel plating on polymer particles.

    Science.gov (United States)

    Fujii, Syuji; Hamasaki, Hiroyuki; Takeoka, Hiroaki; Tsuruoka, Takaaki; Akamatsu, Kensuke; Nakamura, Yoshinobu

    2014-09-15

    Near-monodisperse, micrometer-sized polypyrrole-palladium (PPy-Pd) nanocomposite-coated polystyrene (PS) particles have been coated with Ni overlayers by electroless plating in aqueous media. Good control of the Ni loading was achieved for 1.0 μm diameter PPy-Pd nanocomposite-coated PS particles and particles of up to 20 μm in diameter could also be efficiently coated with the Ni. Laser diffraction particle size analysis studies of dilute aqueous suspensions indicated that an additional water-soluble colloidal stabilizer, poly(N-vinyl pyrrolidone), in the electroless plating reaction media was crucial to obtain colloidally stable Ni-coated composite particles. Elemental microanalysis indicated that the Ni loading could be controlled between 61 and 78 wt% for the 1.0 μm-sized particles. Scanning/transmission electron microscopy studies revealed that the particle surface had a flaked morphology after Ni coating. Spherical capsules were obtained after extraction of the PS component from the Ni-coated composite particles, which indicated that the shell became rigid after Ni coating. X-ray diffraction confirmed the production of elemental Ni and X-ray photoelectron spectroscopy studies indicated the existence of elemental Ni on the surface of the composite particles. PMID:24998053

  7. Electroless nickel plating on optical fiber probe

    Institute of Scientific and Technical Information of China (English)

    Li Huang; Zhoufeng Wang; Zhuomin Li; Wenli Deng

    2009-01-01

    As a component of near-field scanning optical microscope (NSOM),optical fiber probe is an important factor influncing the equipment resolution.Electroless nickel plating is introduced to metallize the optical fiber probe.The optical fibers are etched by 40% HF with Turner etching method.Through pretreatment,the optical fiber probe is coated with Ni-P film by clectrolcss plating in a constant temperature water tank.Atomic absorption spectrometry (AAS),scanning electron microscopy (SEM),and energy dispersive X-ray spectrometry (EDXS) are carried out to charaeterizc the deposition on fiber probe.We have rcproducibly fabricated two kinds of fiber probes with a Ni-P fihn:aperture probe and apertureless probe.In addition,reductive particle transportation on the surface of fiber probe is proposed to explain the cause of these probes.

  8. Direct electroless nickel plating on silicon surface

    Institute of Scientific and Technical Information of China (English)

    HU Guanghui; WU Huihuang; YANG Fangzu

    2004-01-01

    Direct electroless nickel plating on n-Si(100)wafers in alkaline solutions was demonstrated without any activation procedure in advance, the effect of pH and temperature of the solutions on size of metal particles in deposits was examined, and also the element contents of deposits were analyzed by energy disperse spectroscopy (EDS). The results indicated that the size of metal particles increases with increasing temperature or decreasing pH. The possible mechanism of nickel deposition on n-Si(100) was discussed in terms of semiconductor electrochemistry, and the formation of nickel seed crystal on Si was mainly attributed to the generation of atomic hydrogen by electron capture of water molecule from the semiconductor in alkaline solutions.

  9. Electroless copper coating of epoxide plates in an ultrasonic field.

    Science.gov (United States)

    Touyeras, F; Hihn, J Y; Doche, M L; Roizard, X

    2001-07-01

    This paper reports the study of ultrasonic irradiation effects on electroless copper coating on an epoxide resin. Several parameters were monitored, such as plating rates, practical adhesion and internal stress, versus varying acoustic powers at a constant frequency of 530 kHz. Exposure conditions were characterised by both transmitted power and interfacial mass transfer coefficients. Optimum conditions expressed in irradiation time and power were determined. The use of ultrasound during electroless copper plating affects the plating rates and the deposits properties, particularly the practical adhesion which increases whereas the internal stress decreases. Then, the changes in the coating mechanisms are discussed. PMID:11441612

  10. Electroless Ni-B plating for electrical contact applications

    OpenAIRE

    C. T. Dervos; Vassiliou, P.; Novakovic, J.

    2005-01-01

    Electroless Ni-B plating has been tried on steel substrate in an effort to employ low-cost starting materials for electrical contacts or connectors. By selected conditions of heat treatment in a high vacuum environment the plating can acquire Cr-equivalent hardness without the effluents of the hard chromium plating process. The surfaces were characterized under scanning electron microscope and by XRD. The fabricated materials were tested under corrosion conditions by polarization measurements...

  11. Scaling and Removal of Calcium Carbonate on Electroless Plating Surface

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The scaling process of calcium carbonate on a low-energy heat transfer surface-electroless plating surface was investigated in a simulated cooling water system. Owing to the very low surface energy, the electroless plating surface exhibited less scaling susceptibility. A longer induction period and a lower scaling rate were obtained on the low-energy surface compared to copper surface under identical conditions. The calcite particles obtained on the electroless plating surface during the induction period were larger in size than those on copper surface because fewer crystals formed and grew at the same time on the low-energy surface. With increasing surface temperature, the induction period reduced and the scaling rate increased for the low-energy surface. When initial surface temperature was fixed, an increase in fluid velocity would reduce the induction period and increase the scaling rate due to the diffusion effect. However, when the heat flux was fixed, an increase in fluid velocity would decrease the surface temperature, and lead to a longer induction period and a lower scaling rate. The removal experiments of calcium carbonate scale indicated that during post induction period, the detachment was not obvious, while during the induction period, apparent removal of crystal particles was obtained on the electroless plating surface owing to the weak adhesion force. The more frequently the transient high hydrodynamic force acted, the more the detached crystal particles were.

  12. ELECTROLESS NICKEL PLATING ON CHITOSAN-MODIFIED WOOD VENEER

    OpenAIRE

    Lijuan Wang; Haibing Liu

    2011-01-01

    An activation process involving chitosan was conducted to prepare electroless nickel plated wood veneers for electromagnetic interference (EMI) shielding. In this process Pd(Ⅱ) ions were chemically adsorbed on wood surface modified with chitosan. Then they were reduced and dipped into a plating bath in which Ni-P co-deposition was successfully initiated. The coatings were characterized by SEM-EDS and XRD. The metal deposition, surface resistivity, and electromagnetic shielding effectiveness w...

  13. REVIEW ON ELECTROLESS PLATING Ni–P COATINGS FOR IMPROVING SURFACE PERFORMANCE OF STEEL

    OpenAIRE

    HONGYAN ZHANG; JIAOJUAN ZOU; NAIMING LIN; BIN TANG

    2014-01-01

    Electroless plating has been considered as an effective approach to provide protection and enhancement for metallic materials with many excellent properties in engineering field. This paper begins with a brief introduction of the fundamental aspects underlying the technological principles and conventional process of electroless nickel–phosphorus (Ni–P) coatings. Then this paper discusses different electroless nickel plating, including binary plating, ternary composite plating and nickel plati...

  14. Process of electroless plating Cu-Sn-Zn ternary alloy

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Cu-Sn-Zn ternary alloy layer with 10 μm thickness was prepared through electroless plating method. The influences of process conditions including the concentration of metallic salts, reductant and complex agent on Cu-Sn-Zn alloy were studied in details.The stability to bear color changes and corrosion resistance of Cu-Sn-Zn film layer were studied through air-exposure experiment and electrochemical analyses test respectively. The results show that the performances of Cu-Sn-Zn film layer are obviously superior to brass matrix. By use of SEM,EDS and XRD, the morphology, microstructure and chemical composition were investigated. The results show that complex agent can increase the content of Sn and Zn, improve the evenness and compactness and decrease needle holes, therefore the properties of electroless plating layer such as the stability to bear color changes and corrosion resistance are improved remarkably.The probable mechanism of complex agent was discussed.

  15. Electroless silver plating on tetraethoxy silane-bridged fiber glass

    International Nuclear Information System (INIS)

    Tetraethoxy silane was used to functionalize the surface of fiber glass (FG) for adsorption with the electroless plated silver shell. The performance of electroless silver plated FG with tetraethoxy silane modification was compared to that of unmodified FG in terms of mechanical and electrical properties. The silane bridge provided more stability for binding with different concentrations of electroless plating silver ions. The characterization was investigated by using field emission scanning electron microscope (FESEM), X-ray diffraction patterns (XRD), energy-dispersion X-ray (EDX), metal microscope (MM) and electric resistance. The Ag coating on TEOS modified FG was more durable than that of unmodified FG in the ball milling test, as confirmed by the data of electric resistance and residue weight. The optimized conditions for producing the Ag coating FG were also investigated. The Ag-Si-FG-3-c product in this study has the lowest electrical resistance of 1.56 × 103 Ω/cm2 and good mechanical stability as exhibited in ball milling tests.

  16. Copper plating on the polyimide film by electroless plating techniques for EMI shielding.

    Science.gov (United States)

    Ji, Eun Sun; Cha, Hyun Gil; Kim, Chang Woo; Kang, Dong In; Kang, Young Soo

    2009-12-01

    In this work, the metal plated film was prepared by electroless plating techniques. The film was prepared for the fabrication of EMI shielding. Polyimide film was treated by base solution for etching and then activated by silver. The modified polyimide film was immersed into the electroless copper plating solution which has different molar ratios of nickel in the solution. The thickness and surface morphology of copper layer on the polyimide films were characterized with scanning electron microscopy (SEM). Furthermore, EMI shielding ability of the film was calculated by measuring reflectivity of EM wave on the film surface using the equation of Schelkunoff theory. PMID:19908729

  17. Method for regeneration of electroless nickel plating solution

    Science.gov (United States)

    Eisenmann, Erhard T.

    1997-01-01

    An electroless nickel(EN)/hypophosphite plating bath is provided employing acetic acid/acetate as a buffer and which is, as a result, capable of perpetual regeneration while avoiding the production of hazardous waste. A regeneration process is provided to process the spent EN plating bath solution. A concentrated starter and replenishment solution is provided for ease of operation of the plating bath. The regeneration process employs a chelating ion exchange system to remove nickel cations from spent EN plating solution. Phosphites are then removed from the solution by precipitation. The nickel cations are removed from the ion exchange system by elution with hypophosphorous acid and the nickel concentration of the eluate adjusted by addition of nickel salt. The treated solution and adjusted eluate are combined, stabilizer added, and the volume of resulting solution reduced by evaporation to form the bath starter and replenishing solution.

  18. Electroless nickel plated graphite fibers and surface behavior in Gr(Ni)/6061Al composite

    Institute of Scientific and Technical Information of China (English)

    WANG Chun-yu; WU Gao-hui; ZHANG Qiang; ZHANG Yun-he; XIU Zi-yang; CHEN Guo-qin

    2006-01-01

    The electroless nickel plated graphite fibers reinforced aluminum matrix composites (Gr(Ni)/Al) were produced by squeeze casting, and the microstructure of Gr(Ni)/Al composite and surface behavior of Ni-P coating were studied. The optimum process of electroless Ni-P plating included: burning to get rid of glue→degreasing→neutralization→acidulating→sensitizing→activation→electroless plating. The surface analysis results show that the electroless nickel plating can diffuse into the graphite fiber surface during the squeeze casting, and the Ni-P coating and aluminum alloys can produce brittle phase NiAl3 or NiAl. The X-ray diffraction(XRD) results indicate that Al4C3 is so little that no Al4C3 peaks are found, and the harmful hl4C3 can be decreased by the electroless plating Ni-P coating. The coating improves the interfacial bonding of continuous graphite fibers reinforced aluminum matrix composites.

  19. Electroless copper plating using dimethylamine borane as reductant

    Institute of Scientific and Technical Information of China (English)

    Yong Liao; Shengtao Zhang; Robert Dryfe

    2012-01-01

    Electroless copper plating was studied using dimethylamine borane (DMAB) as reductant and 1,5,8,12-tetraazadodecane as additive and triethanolamine (TEA) as buffer.The effects of pH,temperature and concentrations of reactants and additives on the anodic oxidation of DMAB and the cathodic reduction of copper ion were investigated.Experimental results indicate that high pH values (10-12.5) promote the oxidation of DMAB,and suppress the reduction of the copper ion,while high bath temperatures (55-70℃)accelerate both anodic oxidation and cathodic reduction.Increase of the Cu2+ and DMAB concentrations can improve the deposition rate of copper plating.Results for a dual-chelating-agent system indicate that 1,5,8,12-tetraazadodecane plays an important role in chelation,while the main effect of TEA is adsorption on copper surfaces to inhibit DMAB oxidation and to promote deposition.

  20. Electroless Nickel Plating and Electroplating on FBG Temperature Sensor

    Institute of Scientific and Technical Information of China (English)

    SHEN Ren-sheng; TENG Rui; LI Xiang-ping; ZHANG Jin; XIA Dao-cheng; FAN Zhao-qi; YU Yong-sen; ZHANG Yu-shu; DU Guo-tong

    2008-01-01

    Metal-coated fiber Bragg grating(FBG) temperature sensors were prepared via electroless nickel(EN) plating and tin electroplating methods on the surface of normal bare FBG.The surface morphologies of the metal-coated layers were observed under a metallographic microscope.The effects of pretreatment sequence,pH value of EN plating solution and current density of electroplating on the performance of the metal-coated layers were analyzed.Meanwhile,the Bragg wavelength shift induced by temperature was monitored by an optical spectrum analyzer.Sensitivity of the metal-coated FBG(MFBG) sensor was almost two times that of normal bare FBG sensor.The measuring temperature of the MFBG sensor could be up to 280 ℃,which was much better than that of conventional FBG sensor.

  1. Studies on Properties and Structure of Electroless Plating Tin Coating

    Institute of Scientific and Technical Information of China (English)

    XU Rui-dong; GUO Zhong-cheng; ZHU Xiao-yun

    2004-01-01

    The composition and structure of electroless tin coating were analyzed by SEM and X-ray diffraction. In the meantime, porosity, solderability and extensibility were determined by physical and chemical methods. The results showed that the porosity of the tin coating increases with the rise of bath temperature and decreases as the plating time rises. Solderability is improved with the rise of thickness of tin coating, and decreases when the tin deposit is heated at 180 ~ 200 ℃. The crystalline grain size becomes bigger and bigger with increasing plating time or bath temperature or coating thickness. X-ray diffraction indicates that only Cu and β-Sn phases show up in the diffraction patterns. Tin coating has a strong joint force with copper substrate and excellent function of electrochemical protection as anode coating.

  2. Review on Electroless Plating Ni-P Coatings for Improving Surface Performance of Steel

    Science.gov (United States)

    Zhang, Hongyan; Zou, Jiaojuan; Lin, Naiming; Tang, Bin

    2014-04-01

    Electroless plating has been considered as an effective approach to provide protection and enhancement for metallic materials with many excellent properties in engineering field. This paper begins with a brief introduction of the fundamental aspects underlying the technological principles and conventional process of electroless nickel-phosphorus (Ni-P) coatings. Then this paper discusses different electroless nickel plating, including binary plating, ternary composite plating and nickel plating with nanoparticles and rare earth, with the intention of improving the surface performance on steel substrate in recent years in detail. Based on different coating process, the varied features depending on the processing parameters are highlighted. Separately, diverse preparation techniques aiming at improvement of plating efficiency are summarized. Moreover, in view of the outstanding performance, such as corrosion resistance, abrasive resistance and fatigue resistance, this paper critically reviews the behaviors and features of various electroless coatings under different conditions.

  3. ELECTROLESS NICKEL PLATING ON CHITOSAN-MODIFIED WOOD VENEER

    Directory of Open Access Journals (Sweden)

    Lijuan Wang

    2011-04-01

    Full Text Available An activation process involving chitosan was conducted to prepare electroless nickel plated wood veneers for electromagnetic interference (EMI shielding. In this process Pd(Ⅱ ions were chemically adsorbed on wood surface modified with chitosan. Then they were reduced and dipped into a plating bath in which Ni-P co-deposition was successfully initiated. The coatings were characterized by SEM-EDS and XRD. The metal deposition, surface resistivity, and electromagnetic shielding effectiveness were measured. The morphology of the coating observed by SEM was uniform, compact, and continuous. EDS results showed that the coating consists of 1.8 wt.% phosphorus and 98.2 wt.% nickel. XRD analysis indicated that the coating was crystalline, which is supposed to be related to the low phosphorus content. The plated birch veneers exhibited electro-conductivity with surface resistivity of 0.24 Ω•cm-2 and good electromagnetic shielding effectiveness of over 50 dB in frequency range from10 MHz to 1.5 GHz.

  4. Effects of ultrasonic irradiation on the properties of coatings obtained by electroless plating and electro plating.

    Science.gov (United States)

    Touyeras, F; Hihn, J Y; Bourgoin, X; Jacques, B; Hallez, L; Branger, V

    2005-01-01

    This paper deals with the effects of ultrasonic irradiation on electroless copper coating i.e. metallic deposition on non-conductive substrates and on electroplating on metallic substrates. Ultrasonic irradiation was both applied during activation (surface preparation for the electroless coating) and during plating steps in both cases. Several parameters were monitored, such as plating rates, practical adhesion, hardness, internal stress versus varying acoustic powers and frequencies. Optimum conditions for irradiation time, frequency and power were determined for each step. It appears clearly that ultrasound use affects deposit properties. Then, changes in the coating mechanisms can be discussed, and several parameters will be explored in this paper, to explain enhancement of deposit properties: increase in catalyst specific area, stirring dependence, surface energy evolution, dihydrogen desorption, structure of coating. PMID:15474947

  5. Electroless plating of thin gold films directly onto silicon nitride thin films and into micropores.

    Science.gov (United States)

    Whelan, Julie C; Karawdeniya, Buddini Iroshika; Bandara, Y M Nuwan D Y; Velleco, Brian D; Masterson, Caitlin M; Dwyer, Jason R

    2014-07-23

    A method to directly electrolessly plate silicon-rich silicon nitride with thin gold films was developed and characterized. Films with thicknesses coating planar, curved, and line-of-sight-obscured silicon nitride surfaces. PMID:24999923

  6. Functionalization of particles and selective functionalization of surfaces for the electroless metal plating process

    OpenAIRE

    Mondin, Giovanni

    2014-01-01

    Electroless plating is a metal deposition technique widely used in the coating industry. It is the method of choice to plate substrates with complex geometries and nonconductive surfaces, such as polymers and ceramics, since it is based on a chemical reduction in solution rather than on an external electrical energy source like the electroplating method. Among others, examples of well-established applications are the electroless deposition of decorative metal coatings such as gold and silver,...

  7. Investigation of peculiarities of electroless copper plating systems using hydroxycarboxylic acids as Cu(II) ligands

    OpenAIRE

    Kepenienė, Virginija

    2012-01-01

    Electroless metal coating technique is one of the elegant ways of metal coating by controlling the temperature and pH of the plating bath in which there is no usage of electric current. The industrial electroless copper plating solution containing formaldehyde as reducing agent are known from the middle of the last century and are widespread in the practice up to now. However many chemical compounds used in such kind technological processes are hazardous for total environment, therefore the e...

  8. Electroless Ni-B plating for electrical contact applications

    Directory of Open Access Journals (Sweden)

    Dervos, C. T.

    2005-12-01

    Full Text Available Electroless Ni-B plating has been tried on steel substrate in an effort to employ low-cost starting materials for electrical contacts or connectors. By selected conditions of heat treatment in a high vacuum environment the plating can acquire Cr-equivalent hardness without the effluents of the hard chromium plating process. The surfaces were characterized under scanning electron microscope and by XRD. The fabricated materials were tested under corrosion conditions by polarization measurements. Semispherical nickel plated steel joints were tested in a computer controlled contact make-break apparatus, under simultaneous application of a mechanical and a low-voltage electrical load for 20,000 cycles. After heat treatment the plating acquires a crystalline structure with very good adhesion to the substrate material. Corrosion decreases and increased hardness is obtained. The surface is also characterized by good electrical properties during aging accelerated tests.

    Se ha investigado la deposición de Ni-B por vía química sobre un substrato de acero, con el fin de poder emplear materiales de bajo coste para los contactos o conectores eléctricos. Mediante condiciones específicas de tratamiento térmico en un ambiente de alto vacío, la deposición puede alcanzar durezas equivalentes al cromo (Cr sin los efluentes del proceso de cromado duro. Las superficies se caracterizaron en el microscopio electrónico de barrido y mediante DRX. Los materiales fabricados se ensayaron bajo condiciones de corrosión utilizando mediciones de polarización. Se ensayaron las juntas semiesféricas de acero niquelado en un equipo de contactos controlado por ordenador bajo la aplicación simultánea de una carga mecánica y de una carga eléctrica de bajo voltaje durante 20.000 ciclos. Después del tratamiento térmico, el recubrimiento adquiere una estructura cristalina con muy buena adherencia al material del substrato. Se consigue una menor corrosión y mayor

  9. Electroplating zinc transition layer for electroless nickel plating on AM60 magnesium alloys

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-min; ZHOU Wan-qiu; HAN En-Hou

    2006-01-01

    Electroplating zinc coating as transition layer of electroless nickel plating on AM60 magnesium alloys was investigated. The zinc film can be deposited in a pyrophosphate bath at 50-60 ℃ under current density of 0.5-1.5 A/dm2. A new fore treatment technology was applied by acid cleaning with a solution containing molybdate and phosphorous acid, by alkaline cleaning in a bath containing molybdate and sodium hydroxide. The subsequent electroless plating was carried out in nickel sulfate bath. The SEM observation shows that the deposition is uniform and compact. The polarization curve measurements show that the corrosion potential of the zinc plating in 3.5% NaCl is about -1.3 V(vs SCE) which is noble than that of magnesium substrate. The zinc electroplating can be applied as the pretreatment process for electroless nickel plating on magnesium alloys.

  10. Effect of MWNT electroless Ag plating on field emission properties of MWNT/Ag nanocomposite cathodes

    Energy Technology Data Exchange (ETDEWEB)

    Ye Yun, E-mail: yeyun07@fzu.edu.cn [College of Physics and Information Engineering, Fuzhou University, Fuzhou 350002 (China); Guo Tailiang [College of Physics and Information Engineering, Fuzhou University, Fuzhou 350002 (China)

    2013-01-01

    Highlights: Black-Right-Pointing-Pointer Ag nanoparticles and coating were electroless plated onto the surface of CNTs. Black-Right-Pointing-Pointer A low turn on field of CNT/Ag cathode was achieved. Black-Right-Pointing-Pointer A new way for high stability of CNT/Ag cathode was suggested. - Abstract: Field emission properties of multiwall carbon nanotube (MWNT) electroless Ag plating nanocomposite cathodes fabricated using screen printing were studied. The MWNT was purified and electroless plated with Ag. The results of field emission scanning electron microscopy (FESEM) showed that the morphology of Ag electroless plating on the surface of MWNT depended on the temperature of electroless plating. Experiments showed that the stability of MWNT/Ag nanocomposite cathodes had no more than 10% degradation, achieving a field emission current density of 4.0 mA/cm{sup 2} at an applied electric field of 0.5 V/{mu}m for 50 h. The proposed MWNT/Ag nanocomposite cathodes possess good field emission properties and have potential for application in field emission displays.

  11. Mechanical assisted electroless barrel-plating Ni-P coatings on magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    Zhaoxia PING; Juntao YUAN; Yedong HE; Xiaogang LI

    2009-01-01

    A mechanically assisted electroless barrel-plating Ni-P was carried out in a rolling drum containing Mg alloy specimens and ceramic balls, which was submerged in a bath containing electroless plating solution. It is demonstrated that the Ni-P coatings deposited by this novel technique have a crystallized Ni-P solid solution structure,showing fine-grains, higher hardness, and higher corrosion resistance compared with the conventional electroless plated amorphous Ni-P coatings. After heat treatment at 400 ~C for 1 h, the structure of such Ni-P coatings were transformed to a structure with Ni-Ni3P double phases, and cracks in these coatings could not-be observed,whereas cracks appeared seriously in the conventional electroless plated Ni-P coating after same heat treatment. Therefore, both hardness and corrosion resistance of these Ni-P coatings can be improved further by heat treatment. All of these beneficial effects can be attributed to the role of mechanical attrition during the mechanically assisted electroless barrel-plating process.

  12. Enhanced microwave absorbing properties and heat resistance of carbonyl iron by electroless plating Co

    Science.gov (United States)

    Wang, Hongyu; Zhu, Dongmei; Zhou, Wancheng; Luo, Fa

    2015-11-01

    Co coated carbonyl iron particles (Co (CI)) are fabricated through electroless plating method, and the electromagnetic microwave absorbing properties are investigated in the frequencies during 8.2-12.4 GHz. The complex permittivity of CI particles after electroless plating Co is higher than that of raw CI particles due to improvment of the polarization process. Furthermore, according to the XRD and TG results, the Co layer can enhance the heat resistance of CI particles. The bandwidth below -10 dB can reach 3.9 GHz for the Co(CI) absorbent. The results indicate that the electroless plating Co not only enhances the absorbing properties but also improves the heat resistance of CI.

  13. Direct electroless Ni-P plating on AZ91D magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    LI Zhong-hou; QU Yu-ping; ZHENG Feng; DAI A-gan

    2006-01-01

    An electroless Ni-P plating treatment was applied on AZ91D magnesium alloy to improve its corrosion resistance. Optimum pretreatment conditions and optimum bath of electroless nickel plating for magnesium alloy were found through many experiments. In order to avoid bother of pre-plating medium layer, a set of procedure of direct electroless Ni-P under the acid condition was investigated. The properties of the coating with 10% phosphorus were investigated. The results show that a coating with high hardness, low porosity and good adhesive strength is obtained. X-ray diffraction patterns show that the structure of the coating is an amorphous phase. After annealing at 400 ℃, the amorphous phase of Ni-P is transformed to crystalline phases,and some intermetallics as Ni3P and Ni5P2 are deposited from Ni -P solid solution along with an enhancing hardness from Hv 450 to Hv 910.

  14. Regeneration and reuse of exhausted solutions of electroless nickel plating wood veneer

    Institute of Scientific and Technical Information of China (English)

    WANG Lijuan; LI Jian; LIAN Aizhen

    2006-01-01

    The regeneration of exhausted solutions of electroless nickel plating wood veneer was realized using soluble calcium salt to precipitate and remove phosphite and then using fluoride to remove residual calcium ions from the solution.The effect of the pH value of the solution,treatment temperature and the molar ratio of calcium ions to phosphite ions on the removal efficiency of phosphite was investigated.Wood veneer was electroless plated using regenerated solutions.A coating with better electrical conductivity and electromagnetic shielding was obtained.

  15. Enhanced microwave absorbing properties and heat resistance of carbonyl iron by electroless plating Co

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hongyu, E-mail: wanghongyu07010310@163.com; Zhu, Dongmei; Zhou, Wancheng; Luo, Fa

    2015-11-01

    Co coated carbonyl iron particles (Co (CI)) are fabricated through electroless plating method, and the electromagnetic microwave absorbing properties are investigated in the frequencies during 8.2–12.4 GHz. The complex permittivity of CI particles after electroless plating Co is higher than that of raw CI particles due to improvment of the polarization process. Furthermore, according to the XRD and TG results, the Co layer can enhance the heat resistance of CI particles. The bandwidth below −10 dB can reach 3.9 GHz for the Co(CI) absorbent. The results indicate that the electroless plating Co not only enhances the absorbing properties but also improves the heat resistance of CI. - Highlights: • The Co-coated carbonyl iron Co(CI) particles were prepared by electroless plating. • The electromagnetic wave absorbing properties of Co(CI) particles were studied. • The heat treatment on the absorbing property of Co(CI) particles was studied. • The Co(CI) particles have good absorbing property when compared with CI.

  16. The Studies of Composite Electroless Plating Process on Sintering Ndfeb Permanent Magnet

    Institute of Scientific and Technical Information of China (English)

    HUJian-wen; MAJing; YANDong-qing; GAOQing; MENGYong-qiang

    2004-01-01

    A reasonable pre-treatment and an ultrasonic pre-plating Cu film were applied for sintering NdFeB permanent magnet. The samples were then plated in neutral bath (PH=7) for 40rnin and in acidic bath (PH=4.8-5.1) for 2h. A composite electroless plating with different phosphor content was obtained. The results show that the composite plating coatings are dense and have a strong bond with the substrate, which contribute to the excellent corrosion resistance of the plating coating.

  17. The Studies of Composite Electroless Plating Process on Sintering Ndfeb Permanent Magnet

    Institute of Scientific and Technical Information of China (English)

    HU Jian-wen; MA Jing; YAN Dong-qing; GAO Qing; MENG Yong-qiang

    2004-01-01

    A reasonable pre-treatment and an ultrasonic pre-plating Cu film were applied for sintering NdFeB permanent magnet. The samples were then plated in neutral bath (PH=7) for 40min and in acidic bath (PH=4.8~5.1) for 2h. A composite electroless plating with different phosphor content was obtained. The results show that the composite plating coatings are dense and have a strong bond with the substrate, which contribute to the excellent corrosion resistance of the plating coating.

  18. Electroless plating and magnetic properties of Co–Zn–P coating on short carbon fibres

    Indian Academy of Sciences (India)

    Xinghua Su; Chengwen Qiang

    2012-12-01

    A layer of Co–Zn–P alloys was coated on short carbon fibre (CFs) surfaces using electroless plating method. The influence of the concentration of Co2+ and Zn2+ and reaction time on the plating rate were measured by comparing the relative mass gain rate of Co–Zn–P-coated fibres with uncoated carbon fibres prepared under different conditions. The materials characterizations were analysed by field emission scanning electron microscopy, X-ray diffraction and energy dispersive spectroscope. The magnetic properties of Co–Zn–P/CFs composites prepared in different Zn2+ concentration baths were measured by the vibrating sample magnetometer. The best processing parameters of electroless plating of Co–Zn–P coating on short carbon fibres were obtained.

  19. A Novel RF Inductor Fabricated Through MEMS Processing and Electroless Copper Plating

    Institute of Scientific and Technical Information of China (English)

    LIYi; WUWengang; HAOYilong

    2005-01-01

    A novel radio-frequency inductor with single-crystal-silicon spiral structure suspended on glass substrate is reported. The inductor is fabricated by using an improved silicon-glass anodic bonding and deep etching releasing process combined with electroless copper plating technology. The newly developed process is proved simple, stable and easily controlled. Based on the process, the performances of the inductor, such as quality factor, inductance and operating frequency, can be adjusted by changing the structure parameters. Through the electroless copper plating, the silicon spiral structure of the inductor is encapsulated completely by highly conformal copper film. Furthermore, a thin nickel film is plated on the top of the copper layer for passivation and measurement convenience. The thickness of copper and nickel layers influences the characteristics of the inductors largely. The fabricated inductor exhibits high performances. Its quality factor has reached 27 at the frequency arrange from 9 to 11GHz.

  20. Metal deposition by electroless plating on polydopamine functionalized micro- and nanoparticles.

    Science.gov (United States)

    Mondin, Giovanni; Wisser, Florian M; Leifert, Annika; Mohamed-Noriega, Nasser; Grothe, Julia; Dörfler, Susanne; Kaskel, Stefan

    2013-12-01

    A novel approach for the fabrication of metal coated micro- and nanoparticles by functionalization with a thin polydopamine layer followed by electroless plating is reported. The particles are initially coated with polydopamine via self-polymerization. The resulting polydopamine coated particles have a surface rich in catechols and amino groups, resulting in a high affinity toward metal ions. Thus, they provide an effective platform for selective electroless metal deposition without further activation and sensitization steps. The combination of a polydopamine-based functionalization with electroless plating ensures a simple, scalable, and cost-effective metal coating strategy. Silver-plated tungsten carbide microparticles, copper-plated tungsten carbide microparticles, and copper-plated alumina nanoparticles were successfully fabricated, showing also the high versatility of the method, since the polymerization of dopamine leads to the formation of an adherent polydopamine layer on the surface of particles of any material and size. The metal coated particles produced with this process are particularly well suited for the production of metal matrix composites, since the metal coating increases the wettability of the particles by the metal, promoting their integration within the matrix. Such composite materials are used in a variety of applications including electrical contacts, components for the automotive industries, magnets, and electromagnetic interference shielding. PMID:24041548

  1. Effect of electroless plating nickel treatment on electrode properties of Zr-based AB2 type alloy

    Institute of Scientific and Technical Information of China (English)

    文明芬; 翟玉春; 陈廉; 佟敏; 郑华; 马荣骏

    2001-01-01

    An electroless plating nickel treatment was processed to improve the active behaviors and discharge capacities of Zr-based AB2 alloys. The effects of the nickel coating on the surface appearance, the structure of the alloy powders and the electrode characteristics were investigated. It is found that the Ni-rich layer formed through electroless plating nickel treatment plays an important role on the initial activation property and the discharge capacity of Zr-based alloy. The optimal content of electroless plating nickel is about 15 %, and the discharge capacity of the electrode can be increased to 400mA· h·g 1 after 6 cycles. Although coated nickel is beneficial for quick activation and discharge capacity, excessive electroless plating nickel can result in a decreased discharge capacity.

  2. Electroless Plating of Carbon Nanotubes with Copper%碳纳米管的化学镀铜

    Institute of Scientific and Technical Information of China (English)

    凤仪; 袁海龙

    2004-01-01

    A simple chemical method was employed to coat carbon nanotubes with a layer of copper. Due to the hydrophobic nature, large surface curvature, small diameter and large aspect ratio, it is difficult to gain continuous electroless plating layer on the surface of carbon nanotubes. In this paper, a series methods (oxidization, sensitization and activation) are used to add active sites before electroless plating, and the adjustment of the traditional composition of copper electroless plating bath and operating condition can decelerate electroless plating rate. The samples before and after coating were analyzed using transmission electron microscopy and energy-dispersive X-ray spectroscopy. The results showed that the surface of carbon nanotubes was successfully coated with continuous layer of copper, which lays a good foundation for applying carbon nanotubes in composites.

  3. Mechanism and Microstructure of Electroless Ni-Fe-P Plating on CNTs

    Institute of Scientific and Technical Information of China (English)

    XUE Ru-jun; WU Yu-cheng

    2007-01-01

    Electroless Ni-Fe-P alloy plating on the surface of CNTs was carried out with a bath using citrate salt and lactic acid as complex agents. We proposed a chemical reaction mechanism. The morphology, structure and chemical composition of the Ni-Fe-P/CNTs were studied with the aid of a scanning electronic microscope (SEM), X-ray diffraction (XRD) and an energy-dispersive X-ray spectral analysis (EDS). The results show that through a correct pretreatment and electroless plating, Ni-Fe-P/CNTs composite particles can be obtained. The optimum electroless plating parameters of 35-42 ℃ and pH of 8.5-9.7 were achieved. The as-plated Ni-Fe-P alloy is amorphous. After a heat treat-ment at 500 ℃ for 90 min in H2, the coating is transformed into crystalloid Ni3P, Fe2NiP and (Fe,Ni)3P. The Ni-Fe-P al-loy coating on the surface of CNTs is smooth and unique. The amount of Ni on the surface (mass fraction) of the Ni-Fe-P/CNTs composite particles is 29.13%, that of Fe 3.19% and that of P 2.28%.

  4. Nickel Electroless Plating: Adhesion Analysis for Mono-Type Crystalline Silicon Solar Cells.

    Science.gov (United States)

    Shin, Eun Gu; Rehman, Atteq ur; Lee, Sang Hee; Lee, Soo Hong

    2015-10-01

    The adhesion of the front electrodes to silicon substrate is the most important parameters to be optimized. Nickel silicide which is formed by sintering process using a silicon substrate improves the mechanical and electrical properties as well as act as diffusion barrier for copper. In this experiment p-type mono-crystalline czochralski (CZ) silicon wafers having resistivity of 1.5 Ω·cm were used to study one step and two step nickel electroless plating process. POCl3 diffusion process was performed to form the emitter with the sheet resistance of 70 ohm/sq. The Six, layer was set down as an antireflection coating (ARC) layer at emitter surface by plasma enhanced chemical vapor deposition (PECVD) process. Laser ablation process was used to open SiNx passivation layer locally for the formation of the front electrodes. Nickel was deposited by electroless plating process by one step and two step nickel electroless deposition process. The two step nickel plating was performed by applying a second nickel deposition step subsequent to the first sintering process. Furthermore, the adhesion analysis for both one step and two steps process was conducted using peel force tester (universal testing machine, H5KT) after depositing Cu contact by light induced plating (LIP). PMID:26726421

  5. Electroless nickel and ion-plated protective coatings for silvered glass mirrors

    Energy Technology Data Exchange (ETDEWEB)

    Lind, M.A.; Chaudiere, D.A.; Dake, L.S.; Stewart, T.L.

    1982-04-01

    A preliminary examination of two methods of protecting second surface silvered glass mirrors from environmental degradation is presented. One method employed silver mirrors overcoated with Al, Ni, 304 stainless steel, Cr, or an Al/Cu alloy prepared by ion-plating. The other method used conventional wet process silver mirrors protected with a thin electroless nickel coating. No attempt was made to optimize the coatings for either method. These experimental mirrors were compared with conventional paint backed silver/copper mirrors after exposure to elevated temperatures and water vapor in order to estimate their relative environmental stability. The electroless nickel mirrors showed consistently more resistance to these stresses than either the conventional or ion-plated mirrors, suggesting that they may provide more durable field service.

  6. A simple nickel activation process for electroless nickel-phosphorus plating on carbon fiber

    OpenAIRE

    Tingguo Yan; Leihong Li; Lijuan Wang

    2013-01-01

    A new nickel activation process was developed for metalizing the carbon fiber (CF) surface with electroless nickel plating. The oxidation and activation processes were examined using X-ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectrometry (EDS), and X-ray Diffractometry (XRD). XPS analysis showed that HNO3 oxidation improved the O/C ratio of the CF surface, which resulted in an increase in the amount of oxygen-containing groups. As acti...

  7. Development of an Electromagnetic Wave Shielding Textile by Electroless Ni-Based Alloy Plating

    OpenAIRE

    Sonehara, Makoto; Noguchi, Shin; Kurashina, Tadashi; Sato, Toshiro; YAMASAWA, Kiyohito; Miura, Yoshimasa

    2009-01-01

    A polyester nonwoven textile with Ni-based alloy coating was fabricated, and the effect of electromagnetic wave shielding was evaluated. The Ni-based was coated by electroless plating on the textile. The electromagnetic wave shielding effect of the textile with Ni-B coating was about 99.98% over the induction range of 6-13 GHz. Because the textile has thin, light, flexible, and breathable characteristics, it will be versatile for the various electromagnetic wave shielding applications.

  8. Study of electroless copper plating on ABS resin surface modified by heterocyclic organosilane self-assembled film

    Indian Academy of Sciences (India)

    H N Zhang; J Wang; F F Sun; D Liu; H Y Wang; F Wang

    2014-02-01

    6-(3-triethoxysilylpropyl)amino-1, 3, 5-triazine-2, 4-dithiol monosodium (TES) was used to fabricate self-assembled film on corona pretreated acrylonitrile–butadiene–styrene (ABS) resin surface. The self-assembled film modified ABS resin was treated by electroless copper plating. Orthogonal test was carried out to study optimal condition of the process. The surface appearance, plating rate and thickness of electroless copper films were investigated to determine the optimal time of corona-discharge, self-assembly and electroless copper plating. SEM results indicated that porous morphology appeared on ABS resin surface modified by TES self-assembled film and the surface roughness also increased. The adhesion test showed that the adhesion property between ABS resin and copper was excellent. The surface of electroless copper film had high brightness under the optimal condition of 1 min corona-discharge, 30 min self-assembly and 10 min electroless copper plating. The electroless-copper plating temperature was 55 ∼ 60°C and pH was 13 ∼ 13.5.

  9. Comparison Between Electrolysis and Reduction for Treatment of Spent Electroless Nickel Plating Bath

    Institute of Scientific and Technical Information of China (English)

    YAN Lei; LI Shuqin; YU Xiujuan

    2009-01-01

    There are lots of residual nickel and organic compounds in the spent electroless nickel plating bath. It not only wastes resource but also causes environmental pollution if the wastewater is discharged without treatment. In this paper, electrolytic method and reduction method for treating spent electroless nickel plating bath were compared. The factors studied included reaction time, pH, temperature, effectiveness and cost. It was found that the recovery rate of nickel by reduction was 99.9% under the condition ofpH 6, 50℃ for 10 min. The purity of reclaimed nickel was 66.1%. This treatment needed about 16 g NaBH4 for a liter spent solution, which cost RMB 64 Yuan. For electrolysis method, with pH 7.6, 80℃, 0.45 A (current intensity) for 2 h, the recovery rate reached 97.3%. The purity was 88.5% for the reclaimed nickel. Moreover, it was found that through electrolysis, the value of TOC (Total Organic Carbon) decreased from 114 to 3.08 g·L-1 with removal rate of 97.3%. The main cost of electrolysis came from electric energy. It cost about 0.09 kWh (less than RMB 0.1 Yuan) per liter wastewater. Compared with reduction, electrolysis had more advantages, so the priority of selection should be given to the electrolysis method for the treatment of spent electroless nickel plating bath.

  10. Polycarbonate activation for electroless plating by dimethylaminoborane absorption and subsequent nanoparticle deposition

    Science.gov (United States)

    Muench, Falk; Bohn, Sebastian; Rauber, Markus; Seidl, Tim; Radetinac, Aldin; Kunz, Ulrike; Lauterbach, Stefan; Kleebe, Hans-Joachim; Trautmann, Christina; Ensinger, Wolfgang

    2014-07-01

    Electroless plating of metal films on polymer substrates usually requires the presence of metal particles acting as catalytically active nuclei for the deposition reaction. Herein, we present a novel and versatile approach towards the activation of polycarbonate substrates with metal nanoparticles. It is based on the diffusion of dimethylaminoborane into the polymer matrix, followed by reaction of the sensitized substrates with metal salt solutions. The reducing agent uptake was controlled by changing the duration of the sensitization and the dimethylaminoborane concentration in the sensitization solution. Different seed types (Ag, Au, Pd, Pt and Rh) were deposited by variation of the activation solution. The proposed mechanism was confirmed with FTIR and TEM measurements. In addition, AFM revealed that apart from a slight roughening in the nanometer range, the surface morphology of the polymer remained unchanged, rendering the method viable for template-based nanomaterial fabrication. Due to its pronounced variability, the new technique allows to tailor the activity of polymer substrates for consecutive electroless plating. The feasibility and nanoscale homogeneity of the process were proven by the electroless fabrication of well-defined Au and Pt nanotubes in ion-track etched polycarbonate templates. The combination of features (use of simple and easily scalable wet-chemical processes, facile seed variation, high activation quality on complex surfaces) renders the outlined technique promising for the fabrication of intricate nanomaterials as well as for the metallization of macroscopic work pieces.

  11. Removal of platinum group metals from the used auto catalytic converter

    Directory of Open Access Journals (Sweden)

    A. Fornalczyk

    2009-04-01

    Full Text Available Recycling of platinum group metals from the used auto catalytic converters is profitable from ecological and also economical point of view. This work presents the analysis of the chances of removing the platinum group metals (PGM from the used auto catalytic converters applying pyrometallurgical and hydrometallurgical methods. The characteristics of auto catalytic converter is shown as well the available technologies used for processing the auto catalytic converters are also presented.

  12. Removal of platinum group metals from the used auto catalytic converter

    OpenAIRE

    A. Fornalczyk; M. Saternus

    2009-01-01

    Recycling of platinum group metals from the used auto catalytic converters is profitable from ecological and also economical point of view. This work presents the analysis of the chances of removing the platinum group metals (PGM) from the used auto catalytic converters applying pyrometallurgical and hydrometallurgical methods. The characteristics of auto catalytic converter is shown as well the available technologies used for processing the auto catalytic converters are also presented.

  13. Preparation and characterization of molybdenum powders with copper coating by the electroless plating technique

    Institute of Scientific and Technical Information of China (English)

    WANG Guangjun; WANG Dezhi

    2008-01-01

    Molybdenum powders with a diameter of approximately 3 μm were coated with copper using the electroless plating technique in the pH 12.5-13 and temperature range of 55-75℃.The optimization of the electroless copper bath was evaluated through the combination of process parameters like pH and temperature.The optimized values of pH and temperature were found to be 12.5 and 60℃,respectively,which attributes to the bright maroon color of the coating with an increase in weight of 46%.The uncoated and coated powders were subjected to microstructural studies using scanning electron microscope (SEM) and the phases were analyzed using X-ray diffraction (XRD).An attempt was made to understand the growth mechanism of the coating.The diffusion-shrinkage autocatalytic model was suggested for copper growth on the molybdenum surface.

  14. A New Activation Method for Electroless Metal Plating: Palladium Laden via Bonding with Self-Assembly Monolayers

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new activation method has been developed for electroless copper plating on silicon wafer based on palladium chemisorption on SAMs of APTS without SnCl2 sensitization and roughening condition. A closely packed electroless copper film with strong adhesion is successfully fonned by AFM observation. XPS study indicates that palladium chemisorption occurred via palladium chloride bonding to the pendant amino group of the SAMs.

  15. Direct Electroless Nickel Plating on AZ91D Magnesium Alloy from a Sulfate Solution and its Deposition Mechanism

    Institute of Scientific and Technical Information of China (English)

    GUChang-dong; LIANJian-she; LIGuang-yu; NIULi-yuan; JIANGZhong-hao

    2004-01-01

    A bath of electroless plating Ni on the AZ91D magnesium alloy, containing sulfate nickel, was given in this paper. The nucleation mechanism of Ni-P deposits on the AZ91D magnesium alloy was studied by using XRD and SEM. The electroless Ni-P deposits were preferentially nucleated on the β(Mg17Al12) phase and extended to the primary and eutectic α phases of the AZ91D magnesium alloy.

  16. Preparation and magnetic properties of Ni-P-La coating by electroless plating on silicon substrate

    Science.gov (United States)

    Gao, Yun; Wang, Jihui; Yuan, Jing; Li, Haiqin

    2016-02-01

    Ni-P-La coatings were prepared on Si substrate by electroless plating method under different La content, pH value, plating temperature and plating time. The surface morphology, chemical composition, structure and magnetic properties of coatings were observed and determined by scanning electron microscope (SEM), energy dispersive X-ray spectrometry (EDS), X-ray diffractometer (XRD) and vibrating sample magnetometer (VSM). The results showed that Ni-P-La coating is smooth and uniform with a cellular morphology grown in columnar manner. With the increase of La content, pH value and plating time, the thickness and saturation magnetization of coating are increased continuously, but the stability of plating bath is decreased greatly with La content and pH value. Under higher plating temperature, the thickness and saturation magnetization of coatings are obviously enhanced. But too high plating temperature is harmful to the plating bath and coating. The optimum plating conditions for Ni-P-La coating is La2O3 addition of 10 mg L-1, pH value of 5.0, plating temperature of 75 °C and plating time of 45 min. The role of La element is to benefit the deposition of Ni element, promote the formation of Ni phase during the annealing process, and thus improve the magnetic properties of Ni-P-La coating.

  17. Factors Affecting the Morphology of Pb-Based Glass Frit Coated with Ag Material Prepared by Electroless Silver Plating

    Science.gov (United States)

    Huang, Bei; Gan, Weiping; Zhou, Jian; Li, Yingfen; Lin, Tao; Liu, Xiaogang

    2014-05-01

    Pb-based glass frit coated with nanosilver material for Si solar cell applications has been directly prepared by electroless silver plating. Activation of the glass frit was accomplished by using glycol, with the aim of reducing the silver ions to elemental silver on the surface of the glass frit. Electroless silver plating onto the glass frit was successfully realized using two kinds of electroless plating bath. However, the morphology of the composite powder greatly affected the modality, sheet resistance, series resistance, and photoelectric conversion efficiency of the conducting silver films. We found that the activation temperature affected the number and distribution of silver nanoparticles. Meanwhile, the average grain size of the silver particles and the silver content in the Pb-based glass frit coated with Ag material could be controlled by adjusting the pH value and loading capacity, respectively, during plating.

  18. Electrochemical behavior of Cu-Zn-Al shape memory alloy after surface modification by electroless plated Ni-P

    Institute of Scientific and Technical Information of China (English)

    LIANG Chenghao; CHEN Bangyi; CHEN Wan; WANG Hua

    2004-01-01

    The electrochemical behavior of Cu-Zn-Al shape memory alloy (SMA) with and without electroless plated Ni-P was investigated by electrochemical methods in artificial Tyrode's solution. The results showed that Cu-Zn-Al SMA engendered dezincification corrosion in Tyrode's solution. The anodic active current densities as well as electrochemical dissolution sensitivity of the electroless plated Ni-P Cu-Zn-Al SMA increased with NaCl concentration rising, pH of solution decreasing and environmental temperature uprising. X-ray diffraction analysis indicated that after surface modification by electroless plated Ni-P, an amorphous plated film formed on the surface of Cu-Zn-Al SMA. This film can effectively isolate matrix metal from corrosion media and significantly improve the electrochemical property of Cu-Zn-Al SMA in artificial Tyrode's solution.

  19. Seeding of silicon by copper ion implantation for selective electroless copper plating

    Energy Technology Data Exchange (ETDEWEB)

    Bhansali, S.; Sood, D.K.; Zmood, R.B. [Microelectronic and Materials Technology Centre, Royal Melbourne Institute of Technolgy, Melbourne, VIC (Australia)

    1993-12-31

    We report on the successful use of copper(self) ion implantation into silicon to seed the electroless plating of copper on silicon (100) surfaces. Copper ions have been implanted to doses of 5E14-6.4E16 ions/cm{sup 2} using a MEEVA ion implanter at extraction voltage of 40kV. Dose was varied in fine steps to determine the threshold dose of 2E15 Cu ions/cm{sup 2} for `seed` formation of copper films on silicon using a commercial electroless plating solution. Plated films were studied with Rutherford backscattering spectrometry, scanning electron microscopy, EDX and profilometry . The adhesion of films was measured by `scotch tape test`. The adhesion was found to improve with increasing dose. However thicker films exhibited rather poor adhesion and high internal stress. SEM results show that the films grow first as isolated islands which become larger and eventually impinge into a continuous film as the plating time is increased. (authors). 5 refs., 1 tab., 3 figs.

  20. Electroless nickel plating of arc discharge synthesized carbon nanotubes for metal matrix composites

    Energy Technology Data Exchange (ETDEWEB)

    Jagannatham, M.; Sankaran, S.; Prathap, Haridoss, E-mail: prathap@iitm.ac.in

    2015-01-01

    Highlights: • Electroless Ni coatings have been performed on CNTs for various deposition times. • The deposition of nickel increased with increase in deposition time. • A deposition time of 60 min has been optimum for uniform coating of Ni on CNTs. • The CNTs with uniform coating of Ni are potential for reinforcements in composites. • Electroless nickel coatings are determined to be super paramagnetic behavior. - Abstract: Electroless nickel (EN) plating was performed on arc discharge synthesized multiwalled carbon nanotubes for various deposition times. X-ray diffraction (XRD), Transmission electron microscopy (TEM), and Raman spectroscopy characterization techniques are used to identify the presence of nickel deposition on the carbon nanotubes (CNTs) and the degree of graphitization. The results indicate that impurities are less in the purified CNTs as compared to raw carbon soot. Increasing deposition time up to 60 min increases uniform deposition of nickel throughout the length of the CNTs. However, for deposition time longer than 60 min, nickel particles are seen separated from the surface of the CNTs. Uniformly coated nickel CNTs throughout their length are potential candidates for reinforcements in composite materials. Magnetic properties of the nickel coated CNTs, with deposition time of 30 and 60 min were also evaluated. The magnetic saturation of nickel coated CNTs with deposition time of 30 min is less compared to nickel coated CNTs with deposition time of 60 min.

  1. Environmentally friendly electroless plating for Ag/TiO2-coated core-shell magnetic particles using ultrasonic treatment.

    Science.gov (United States)

    Kim, Soo-Dong; Choe, Won-Gyun; Jeong, Jong-Ryul

    2013-11-01

    In this work, high-reflectance brilliant white color magnetic microspheres comprising a Fe/TiO2/Ag core-shell structure with a continuous, uniform compact silver layer were successfully fabricated by TiO2-assisted electroless plating in a simple and eco-friendly method. The coating procedure for TiO2 and Ag involved a sol-gel reaction and electroless plating with ultrasound treatment. The electroless plating step was carried out in an eco-friendly manner in a single process without environmentally toxic additives. The TiO2 layer was used as a modification layer between the Fe microspheres and the silver layer to improve adhesion. A continuous and compact silver layer could be formed with a high degree of morphological control by introducing ultrasonication and adjusting the ammonium hydroxide concentration. PMID:23611665

  2. ELECTROLESS COPPER PLATING ON FRAXINUS MANDSHURICA VENEER USING GLYOXYLIC ACID AS REDUCING AGENT

    OpenAIRE

    Lijuan Wang; Lili Sun; Jian Li

    2011-01-01

    Copper coating was deposited on Fraxinus mandshurica veneers for preparing EMI shielding composite by electroless plating using glyoxylic acid as reducing agent in the solution. XPS and SEM were used to analyze the activation process. It was found that a continuous chitosan membrane was loaded on the wood surface. XPS results showed that Pd(II) ions were chemically adsorbed on a chitosan membrane on the wood surface through an N-Pd σ coordination bond. After reduction, part of Pd(II) absorbed...

  3. Study of electroless nickel plating on PerFactoryTM rapid prototype model

    OpenAIRE

    J.C. Rajaguru; C. Au, M. Duke

    2012-01-01

    This paper presents an investigation of electroless nickel plating on PerFactoryTM rapid prototype model built on PerFactoryTM R05 material. PerFactoryTM R05 is acrylic based photo sensitive resin. It is a popular material in rapid prototyping using PerFactoryTM method which employs addictive manufacturing technique to build prototypes for visual inspection, assembly etc. Metallization of such a prototype can extend the application envelop of the rapid prototyping technique as they can be use...

  4. High Aspect Pattern Formation by Integration of Micro Inkjetting and Electroless Plating

    CERN Document Server

    Gian, P W; Liang, Y N; Lok, B K; Lu, C W; Ooi, B L

    2008-01-01

    This paper reports on formation of high aspect micro patterns on low temperature co-fired ceramic (LTCC) substrates by integrating micro inkjetting with electroless plating. Micro inkjetting was realized by using an inkjetting printer that ejects ink droplets from a printhead. This printhead consists of a glass nozzle with a diameter of 50 micrometers and a piezoelectric transducer that is coated on the nozzle. The silver colloidal solution was inkjetted on a sintered CT800 ceramic substrate, followed by curing at 200 degrees C for 60 minutes. As a result, the silver trace with a thickness of 200 nm was obtained. The substrate, with the ejected silver thin film as the seed layer, was then immersed into a preinitiator solution to coat a layer of palladium for enhancing the deposition of nickel. Electroless nickel plating was successfully conducted at a rate of 0.39 micrometers /min, and the thickness of traces was plated up to 84 micrometers. This study demonstrates that the integration of inkjetting with plat...

  5. Characterization of nano-sized SiC@Ni composite fabricated by electroless plating method.

    Science.gov (United States)

    Xu, Zhan; Chen, Yigang

    2013-02-01

    A nano-sized SiC@Ni composite was prepared by simple electroless plating method. Nickel can be reduced by Na2H2PO2 under the catalysis of Pd to despite onto the surface of SiC nanoparticles. The composite structure was characterized by means of TEM images, XRD and the components were analyzed using EDS. The coating layer on the SiC particles was several nanometers thick and mainly in a form of fine Ni crystalline grain and amorphous Ni-P alloy. By increasing the concentration of Na2H2PO2 in the plating bath, the uniformity of the coating layer can be improved obviously. Both of the magnetism and crystallinity of Ni coatings depends on the P content in the coating which can be decreased by increasing the pH values of plating solutions. The SiC@Ni particles exhibited soft magnetic characteristics. PMID:23646660

  6. Electroless plating Ni-P matrix composite coating reinforced by carbon nanotubes

    Institute of Scientific and Technical Information of China (English)

    邓福铭; 陈小华; 陈卫祥; 李文铸

    2004-01-01

    Ni-P matrix composite coating reinforced by carbon nanotubes (CNTs) was deposited by electroless plating. The most important factors that influence the content of carbon nanotubes in deposits, such as agitation, surfactant and carbon nanotubes concentration in the plating bath were investigated. The surface morphology, structure and properties of the Ni-P-CNTs coating were examined. It is found that the maximum content of carbon nanotubes in the deposits is independent of carbon nanotubes concentration in the plating bath when it is up to 5 mg/L. The test results show that the carbon nanotubes co-deposited do not change the structure of the Ni-P matrix of the composite coating, but greatly increase the hardness and wear resistance and decrease the friction coefficient of the Ni-PCNTs composite coating with increasing content of carbon nanotubes in deposits.

  7. THE ELECTROCHEMICAL PROPERTIES OF Li/FeS BATTERY USING ELECTROLESS NICKEL PLATED FeS POWDER

    OpenAIRE

    SUNG-HYUN KIM; YOUNG-JIN CHOI; DONG-HUN KIM; SUNG-HOON JUNG; KI-WON KIM; HYO-JUN AHN; JOU-HYEON AHN; HAL-BON GU

    2008-01-01

    In order to investigate the electrochemical properties of Li/FeS cell, FeS powder was fabricated by using a high-energy ball milling method. Then, surface of FeS powder was coated with metallic nickel. Nickel coating was conducted by using electroless nickel plating method. Nickel chloride (NiCl2 · 6H2O) was used as the nickel ion source for electroless nickel plating. The effects of nickel coating on the electrochemical properties of FeS electrode for Li/FeS cell were investigated by CV meas...

  8. The Effect of Adding Corrosion Inhibitors into an Electroless Nickel Plating Bath for Magnesium Alloys

    Science.gov (United States)

    Hu, Rong; Su, Yongyao; Liu, Hongdong; Cheng, Jiang; Yang, Xin; Shao, Zhongcai

    2016-10-01

    In this work, corrosion inhibitors were added into an electroless nickel plating bath to realize nickel-phosphorus (Ni-P) coating deposition on magnesium alloy directly. The performance of five corrosion inhibitors was evaluated by inhibition efficiency. The results showed that only ammonium hydrogen fluoride (NH4HF2) and ammonium molybdate ((NH4)2MoO4) could be used as corrosion inhibitors for magnesium alloy in the bath. Moreover, compounding NH4HF2 and (NH4)2MoO4, the optimal concentrations were both at 1.5 ~ 2%. The deposition process of Ni-P coating was observed by using a scanning electron microscope (SEM). It showed corrosion inhibitors inhibited undesired dissolution of magnesium substrate during the electroless plating process. In addition, SEM observation indicated that the corrosion inhibition reaction and the Ni2+ replacement reaction were competitive at the initial deposition time. Both electrochemical analysis and thermal shock test revealed that the Ni-P coating exhibited excellent corrosion resistance and adhesion properties in protecting the magnesium alloy.

  9. The Effect of Adding Corrosion Inhibitors into an Electroless Nickel Plating Bath for Magnesium Alloys

    Science.gov (United States)

    Hu, Rong; Su, Yongyao; Liu, Hongdong; Cheng, Jiang; Yang, Xin; Shao, Zhongcai

    2016-08-01

    In this work, corrosion inhibitors were added into an electroless nickel plating bath to realize nickel-phosphorus (Ni-P) coating deposition on magnesium alloy directly. The performance of five corrosion inhibitors was evaluated by inhibition efficiency. The results showed that only ammonium hydrogen fluoride (NH4HF2) and ammonium molybdate ((NH4)2MoO4) could be used as corrosion inhibitors for magnesium alloy in the bath. Moreover, compounding NH4HF2 and (NH4)2MoO4, the optimal concentrations were both at 1.5 ~ 2%. The deposition process of Ni-P coating was observed by using a scanning electron microscope (SEM). It showed corrosion inhibitors inhibited undesired dissolution of magnesium substrate during the electroless plating process. In addition, SEM observation indicated that the corrosion inhibition reaction and the Ni2+ replacement reaction were competitive at the initial deposition time. Both electrochemical analysis and thermal shock test revealed that the Ni-P coating exhibited excellent corrosion resistance and adhesion properties in protecting the magnesium alloy.

  10. A simple nickel activation process for electroless nickel-phosphorus plating on carbon fiber

    Directory of Open Access Journals (Sweden)

    Tingguo Yan

    2013-02-01

    Full Text Available A new nickel activation process was developed for metalizing the carbon fiber (CF surface with electroless nickel plating. The oxidation and activation processes were examined using X-ray Photoelectron Spectroscopy (XPS, Scanning Electron Microscopy (SEM, Energy Dispersive X-ray Spectrometry (EDS, and X-ray Diffractometry (XRD. XPS analysis showed that HNO3 oxidation improved the O/C ratio of the CF surface, which resulted in an increase in the amount of oxygen-containing groups. As activation time increased, both Nio cluster and Ni-P deposits increased. More than 50 mg of Nio clusters formed on the surface of 1g CF. SEM observations illustrated that particles and island-like shapes were developed from the Nio cluster, which helped to initiate the electroless nickel-plating on the CF surface. A continuous and compact coating with a thickness of about 2 to 3 μm was obtained. EDS results showed that the nickel and phosphorus content in the deposits was 97.34 wt.% and 2.66 wt.%, respectively. XRD indicated that the Ni-P coating was crystalline and the maximum deposition on 1 g CFs was as high as 9000 mg. As the results of the observations reveal, the activation method is a feasible alternative to Pd activation.

  11. Electroless Plating of Ni-Fe-P Alloy and Corrosion Resistance of the Deposit

    Institute of Scientific and Technical Information of China (English)

    Senlin WANG

    2005-01-01

    Electroless Ni-Fe-P alloys in an alkaline bath were plated. Theeffects of deposition parameters on the plating rate and the coating composition were examined. The weight loss test and the anodic polarization measurement of the deposits in 3.5 wt pct NaCl solution (pH7.0) showed that the deposits with the mole ratio of NiSO4/FeSO4 being 0.07:0.03, pH8.0 and 7.5 possess better corrosion resistance than that of the other deposits and the Ni-Fe-P deposits did not form passive films in this environment. In 5.0 wt pct NaOH solution, the Ni-Fe-P deposits have better corrosion resistance and formed passive films.

  12. Effect of plating time on growth of nanocrystalline Ni–P from sulphate/glycine bath by electroless deposition method

    Indian Academy of Sciences (India)

    N Latha; V Raj; M Selvam

    2013-08-01

    Nanocrystalline nickel phosphorus (NC-Ni–P) deposits from sulphate/glycine bath using a simple electroless deposition process is demonstrated. In the present investigation, nanoporous alumina films are formed on the aluminium surface by anodization process followed by deposition of nickel onto the pores by electroless plating method. Anodic aluminium oxide surface was first sensitized and activated by using palladium chloride solution before immersing into the electroless nickel bath. Electroless nickel plating was carried out from the optimized bath by changing the deposition time from 20 to 1800 s at a constant temperature of 80 °C and a pH of 4.0. Surface morphology, elemental composition, structure and reflectance of the deposits have been analysed by using scanning electron microscopy, atomic force microscopy, energy dispersive X-ray analysis, X-ray diffractometry and UV-visible spectroscopic studies, respectively. Electroless nickel deposits formed at an early stage produces dense uniform nanocrystals containing higher percentage of atomic phosphorus with cubic Ni (111) structure. As the deposition time increased, nanocrystalline sharp peak became amorphous and dimension of the crystal size varied from 54 to 72 nm.

  13. ELECTROLESS COPPER PLATING ON FRAXINUS MANDSHURICA VENEER USING GLYOXYLIC ACID AS REDUCING AGENT

    Directory of Open Access Journals (Sweden)

    Lijuan Wang

    2011-06-01

    Full Text Available Copper coating was deposited on Fraxinus mandshurica veneers for preparing EMI shielding composite by electroless plating using glyoxylic acid as reducing agent in the solution. XPS and SEM were used to analyze the activation process. It was found that a continuous chitosan membrane was loaded on the wood surface. XPS results showed that Pd(II ions were chemically adsorbed on a chitosan membrane on the wood surface through an N-Pd σ coordination bond. After reduction, part of Pd(II absorbed formed very little Pd(0 particles on the chitosan-treated wood surface. The activated wood veneers were immersed into a plating bath in which copper film was successfully initiated. The coatings were characterized by SEM-EDS, XPS, and XRD. The metal deposition, surface resistivity, and electromagnetic shielding effectiveness were measured. The morphology of the coating was uniform, compact, and continuous. The wood grains were preserved on the plated wood veneer, which had a copper-like color and sheen. EDS, XPS, and XRD results indicated that the coating consisted of Cu0 with crystalline structure. The surface resistivity and copper deposition reached 175.14 mΩ•cm-2 and 21.66 g/m2 when the veneer was pretreated with 0.8 % chitosan for 8 min and plated for 30 min at 55 oC. The plated veneers exhibited good electromagnetic shielding effectiveness of over 60 dB in frequency ranging from10 MHz to 1.5 GHz.

  14. 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.

  15. High-adhesion Cu patterns fabricated by nanosecond laser modification and electroless copper plating

    Science.gov (United States)

    Lv, Ming; Liu, Jianguo; Zeng, Xiaoyan; Du, Qifeng; Ai, Jun

    2015-10-01

    Adhesion strength is a crucial factor for the performance and reliability of metallic patterns on insulator substrates. In this study, we present an efficient technique for selective metallization of alumina ceramic with high adhesion strength by using nanosecond laser modification and electroless copper plating. Specifically, a 355 nm Nd:YVO4 ultraviolet (UV) laser was employed not only to decompose palladium chloride film locally for catalyzing the electroless reaction, but also to modify the ceramic surface directly using its high fluence. An orthogonal experiment was undertaken to study the effects of processing parameters including laser fluence, scanning speed and scanning line interval on adhesion strength. The adhesion strength was measured by pulling a metallic wire soldered into the copper coating perpendicular to the substrate using a pull tester. The results have shown that a strong adhesion between the copper coating and the alumina ceramic, higher than the tensile strength of tin-lead solder was obtained. Surface and interface characteristics were investigated to understand that, whose results have shown that the high-aspect-ratio microstructures formed by the laser modification is the major reason for the improvement of adhesion.

  16. Crystallization behavior of electroless Co-Ni-B alloy plated in magnetic field in presence of cerium

    Institute of Scientific and Technical Information of China (English)

    XUAN Tian-peng; ZHANG Lei; HUANG Qin-hua

    2006-01-01

    The electrochemical property, chemical composition and crystal structure of electroless Co-Ni-B-Ce alloy plated in general state as well as in magnetic field were studied using potentiometer, plasma emission spectrometer, X-ray diffractometer,transmission electron microscope. The results show that the static potential and polarizability of electroless Co-Ni-B alloy are remarkably improved as the plating is carried out in magnetic field in the presence of a little amount of cerium in plating bath.Because of the action of magnetic field and rare earth element cerium, the boron content in alloy decreases, while cobalt and nickel contents increase. As a result, the amorphous Co-Ni-B alloy transforms to the microcrystalline Co-Ni-B-Ce alloy when the plating is in general state, and the Co-Ni-B alloy makes a crystalline transformation because of the action of magnetic field and rare earth element cerium.

  17. High-purity Ni electroless plating on screen-printed anodized Al substrates

    Science.gov (United States)

    Park, Sang-Geon; Lee, Youn-Seoung; Rha, Sa-Kyun

    2016-07-01

    By using an electroless plating process with a Ni source solution including dimethylamine borane (DMAB) at pH 6.5 and 65 ◦ C, we obtained a higher purity Ni film (resistance (Rs) at the interface region is due to the change in the boron concentration caused by surface reactions, and the gradual decrease in Rs in the bulk region is due mainly to the effect of the saturation of boron's concentration on the thickness. From a boron-distribution viewpoint, this result indicates that the B concentration in the Ni film increases gradually with increasing plating time for plating times ≤ 60 s as a kind of initial stage (that is, interface region), and then saturates uniformly for plating times ≥ 300 s as a kind of bulk region. On the other hand, from an electronic structure viewpoint, this result implies that Ni gains 3d electrons with respect to elemental Ni. The increase in the number of electrons gained by the Ni 3d states may result in an enhancement of the electrical conductivity.

  18. Preparation of Ag-coated hollow microspheres via electroless plating for application in lightweight microwave absorbers

    Science.gov (United States)

    Kim, Wook-Joong; Kim, Sung-Soo

    2015-02-01

    Highly conductive Ag film is coated on hollow silica microspheres via electroless plating for application in lightweight microwave absorbers. The Ag plating is conducted using a two-step process of sensitizing and subsequent plating. The complex permeability and permittivity are determined using the reflection/transmission technique in the composite specimens of Ag-coated microspheres and silicone rubber matrix. Due to the large surface area of the microspheres, a relatively high concentration of AgNO3 is required in order to achieve a uniform Ag coating. In addition, a low concentration of fructose reducing agent is recommended for slow plating. The apparent electrical resistance of the Ag-coated microspheres is strongly dependent on the grain morphology. The thin and uniform Ag-coated particles are characterized by their low electrical resistance, which is as low as 0.1 Ω. The lower the electrical resistance of the microspheres, the higher the dielectric constant of the composite specimens, which results from the enhanced space-charge polarization between the conductive microspheres. The microwave absorbance is enhanced with decreases in the electrical resistance of microspheres due to the increased dielectric loss.

  19. ADSORPTION PROPERTIES OF NICKEL-BASED MAGNETIC ACTIVATED CARBON PREPARED BY PD-FREE ELECTROLESS PLATING

    Directory of Open Access Journals (Sweden)

    Boyang Jia

    2011-02-01

    Full Text Available Nickel-based magnetic activated carbon was synthesized from coconut shell activated carbon by electroless plating with palladium-free activation. The effect of plating solution volume on metallic ratio and adsorption capacity were evaluated. The effect of metallic ratio on specific area, pore volume, and magnetic properties were investigated. The morphologies of activated carbon before and after plating were observed by SEM, and the composition of the layer was analyzed by EDS analysis. The results showed that the metallic ratio was increased with the increase of the plating solution volume. The magnetic activated carbon showed high adsorption capacity for methylene blue and a high iodine number. Those values reached 142.5 mg/g and 1035 mg/g, respectively. The specific area and pore volume decreased from 943 m2/g to 859 m2/g and 0.462 ml/g to 0.417 ml/g, respectively. And the layer was more compact and continuous when the metallic ratio reached 16.37 wt.%. In the layer, there was about 97 wt.% nickel and 3 wt.% phosphorus, which indicates that the layer was a low-phosphorus one. At the same time, magnetism was enhanced, making the product suitable for some special applications.

  20. Synthesis and microwave characterization of Co-SiC core-shell powders by electroless plating

    Institute of Scientific and Technical Information of China (English)

    ZHANG Haijun; WU Xiangwei; JIA Quanli; JIA Xiaolin

    2006-01-01

    Co-SiC core-shell powders were prepared by electroless plating. Scanning electron microscopy (SEM) revealed that Co-SiC core-shell powders were of nearly sphere-like shape and were about 0.3 μm. X-ray powder diffraction (XRD)patterns showed that the cobalt powder was hexagonal crystallite. The complex dielectric constant and the complex permeability of Co-SiC core-shell powders-paraffin wax composite were measured by the rectangle waveguide method. It showed that the dielectric loss was less than 0.1 and the magnetic loss was about 0.2 in 8.2-12.4 GHz for prepared Co-SiC core-shell composite powders.

  1. Research on Processes and Adhesion of Electroless Plating Ni-Cu-P Coating

    Institute of Scientific and Technical Information of China (English)

    HUANG Yan-bin; LIU Bo; ZHANG Ping; LIU De-gang; XU Xiao-li

    2004-01-01

    In order to improve the corrosion and wear resistance of the coatings of electroless plating Ni-Cu-P and broaden its application, an optimizing mathematical theory test has been applied in this research. The processing parameters have been optimized and some Ni-Cu-P coatings have been obtained with smooth and glittering appearance. At the same time,the composite complexants can prevent copper from depositing first and obtain coatings with strong adhesion. The porosity of Ni-Cu-P coating (20 μm) ranked class 9. The changing color time of the coating is more than 800 seconds with HNO3 dropthan 0.5 g/L. The surface appearance of deposition is typical cystiform cells by SEM,which rank close and neatly.

  2. Preparation, characterization and wear behavior of carbon coated magnesium alloy with electroless plating nickel interlayer

    Science.gov (United States)

    Mao, Yan; Li, Zhuguo; Feng, Kai; Guo, Xingwu; Zhou, Zhifeng; Dong, Jie; Wu, Yixiong

    2015-02-01

    Poor wear resistance of rare earth magnesium alloys has prevented them from wider application. In this study, composite coating (PVD carbon coating deposited on electroless plating nickel interlayer) is prepared to protect GW83 magnesium alloys against wear. The Ni + C composite coating has a dense microstructure, improved adhesion strength and hardness due to the effective support of Ni interlayer. The wear test result shows that the Ni + C composite coating can greatly prolong the wear life of the magnesium alloy. The wear track of the Ni + C coated magnesium alloy is obviously narrower and shows less abrasive particles as compared with the bare one. Abrasive wear is the wear mechanism of the coatings at the room temperature. In conclusion, the wear resistance of the GW83 magnesium alloy can be greatly improved by the Ni + C composite coating.

  3. Electroless nickel plating of arc discharge synthesized carbon nanotubes for metal matrix composites

    Science.gov (United States)

    Jagannatham, M.; Sankaran, S.; Prathap, Haridoss

    2015-01-01

    Electroless nickel (EN) plating was performed on arc discharge synthesized multiwalled carbon nanotubes for various deposition times. X-ray diffraction (XRD), Transmission electron microscopy (TEM), and Raman spectroscopy characterization techniques are used to identify the presence of nickel deposition on the carbon nanotubes (CNTs) and the degree of graphitization. The results indicate that impurities are less in the purified CNTs as compared to raw carbon soot. Increasing deposition time up to 60 min increases uniform deposition of nickel throughout the length of the CNTs. However, for deposition time longer than 60 min, nickel particles are seen separated from the surface of the CNTs. Uniformly coated nickel CNTs throughout their length are potential candidates for reinforcements in composite materials. Magnetic properties of the nickel coated CNTs, with deposition time of 30 and 60 min were also evaluated. The magnetic saturation of nickel coated CNTs with deposition time of 30 min is less compared to nickel coated CNTs with deposition time of 60 min.

  4. Wear and Corrosion Resistance of Electroless Plating Ni-P Coating on P110 Steel

    Institute of Scientific and Technical Information of China (English)

    LIN Naiming; ZHOU Peng; ZOU Jiaojuan; XIE Faqin; TANG Bin

    2015-01-01

    In order to improve the surface performance and increase the lifetime of P110 oil casing tube steel during operation, electroless plating was conducted to form Ni-P coating onto its surface. The surface morphology/element distribution and phase constitution of the Ni-P coating were analyzed using scanning electron microscope (SEM) equipped with energy dispersive spectrometry (EDS) and X-ray diffraction (XRD). Tribological and electrochemical measurement tests were applied to investigate the wear and corrosion resistance of P110 steel and the Ni-P coating. The results showed that a uniform and compact, high phosphorous Ni-P coating was formed. The obtained Ni-P coating indicated certain friction-reduction effect and lower mass loss during friction-wear tests. The Ni-P coating also exhibited higher corrosion resistance in comparison with bared P110 steel. The obtained Ni-P coating has signifi cantly improved the surface performance of P110 steel.

  5. Microwire formation based on dielectrophoresis of electroless gold plated polystyrene microspheres

    Institute of Scientific and Technical Information of China (English)

    Jiang Hong-Yuan; Ren Yu-Kun; Tao Ye

    2011-01-01

    Microspheres coated with a perfectly conductive surface have many advantages in the applications of biosensors and micro-electromechanical systems. Polystyrene microspheres with the diameter of 10 μm were coated with a 50 nmthick gold layer using an electroless gold plating approach. Dielectrophoresis (DEP) for bare microspheres and shelled microspheres was theoretically analysed and the real part of the Clausius-Mossotti factor was calculated for the two kinds of microspheres. The experiments on the dielectrophoretic characterisation of the uncoated polystyrene microspheres and gold coated polystyrene microspheres (GCPMs) were carried out. Experimental results showed that the gold coated polystyrene microspheres were only acted by a positive dielectrophoretic force when the frequency was below 40M Hz,while the uncoated polystyrene microspheres were governed by a negative dielectrophoretic force in this frequency range.The gold coated polystyrene microspheres were exploited to form the microwire automatically according to their stable dielectrophoretic and electric characterisations.

  6. Microstructure evolution and magnetic properties of Co-B coatings electrolessly plated on hollow microspheres

    International Nuclear Information System (INIS)

    The composites of Co-B coatings on hollow microspheres (Co-B/HMSs) have been successfully synthesized through electroless plating in this paper. The time-dependent microstructure evolution and magnetic properties of the composites were carefully investigated by scanning electron microscope (SEM), energy dispersive X-ray (EDX), and X-ray photoelectron spectroscopy (XPS) and vibrating sample magnetometer (VSM). It was found that small Co-B clusters appeared on the surface of hollow microspheres at catalytic nuclei during the initial stage. Further growth, they converged to form continuous coatings, which were actually stacking of Co-B nuclei. Interestingly, there was an increment of B content in the coating as time wore on, this phenomenon could be interpreted by electrochemical mechanism. Besides, the composites showed magnetic properties, which might be potentially important for the novel materials as magnetic carriers.

  7. Tribological behavior of dual-layer electroless-plated Ag–carbon nanotube coatings

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyun-Dai [Department of Mechanical Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Penkov, Oleksiy V. [Center for Nano-Wear, Yonsei University, Seoul 120-749 (Korea, Republic of); Kim, Dae-Eun, E-mail: kimde@yonsei.ac.kr [Department of Mechanical Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of)

    2013-05-01

    The tribological behavior of electroless Ag-plated carbon nanotube (CNT) dual-layer coatings was assessed and compared to that of the pure CNT coating. The motivation was to protect the surface of CNT coatings from wear by depositing a thin, soft Ag coating. The methods used for coating CNTs and Ag were spin coating and electroless plating, respectively. These coating methods were selected based on their simplicity and cost effectiveness. Wear tests were conducted by sliding the coatings against a stainless steel ball under a 10–30 mN applied load. Results showed that the wear rate of the dual-layer coating was strongly dependent on the thickness of the Ag layer as well as the applied load. At a 10 mN load and an Ag thickness of 65 nm, the wear rate of the dual-layer coating was about 10 times less than that of the pure CNT coating. However, when the thickness of the Ag was decreased to 11.5 nm, the wear rate was significantly higher. Also, the steady-state friction coefficients of the CNT and the dual-layer Ag–CNT coatings were in the range of 0.65–0.73 for all loads. A model of the wear reduction mechanism of the dual-layer Ag–CNT coating was proposed. - Highlights: ► Dual-layer Ag–carbon nanotube (CNT) coatings were deposited on silicon wafer. ► Friction coefficient of the Ag–CNT coatings was about 0.65. ► Wear of Ag–CNT coatings depended on the thickness of Ag layer and the applied load. ► Wear rate of the Ag–CNT coating was 10-fold less than that of the pure CNT coating.

  8. Study on Physical and Chemical Behaviors of Rare Earths in Preparing Ceramic Tube Supported Palladium Film by Electroless Plating

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The rare earths of ytterbium, lanthanum, praseodymium, neodymium and their binary mixtures were respectively added into the traditional electroless plating solution to prepare thin palladium film on the inner surface of porous ceramic tube. The experimental results shows that the addition of rare earths increases palladium deposition rates and the binary mixtures are superior to the single rare earths and the mixture of ytterbium-lanthanum is the most efficient. Adding the mixture of ytterbium-lanthanum can also reduce the plating temperature by 10~20 ℃, shrink the metal crystal size and improve the film densification compared to those by traditional electroless plating. A thin palladium film with 5 μm was prepared and the film made a highly pure hydrogen with a molar fraction of more than 99.97% from a H2-N2 gas mixture. More attentions were paid to analyze the physical and chemical behaviors of the rare earths in palladium film preparation.

  9. Effects of bath composition on the morphology of electroless-plated Cu electrodes for hetero-junctions with intrinsic thin layer solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Woon Young [Surface Technology R& BD Group, Korea Institute of Industrial Technology (KITECH), Gaetbeol-ro 156, Yeonsu-gu, Incheon 406-840 (Korea, Republic of); Lee, Yu Jin [Surface Technology R& BD Group, Korea Institute of Industrial Technology (KITECH), Gaetbeol-ro 156, Yeonsu-gu, Incheon 406-840 (Korea, Republic of); Department of Materials Science & Engineering, Yonsei University, Yonsei-ro 50, Seodaemun-Gu, Seoul 120-749 (Korea, Republic of); Lee, Min Hyung, E-mail: minhyung@kitech.re.kr [Surface Technology R& BD Group, Korea Institute of Industrial Technology (KITECH), Gaetbeol-ro 156, Yeonsu-gu, Incheon 406-840 (Korea, Republic of)

    2015-07-31

    The morphology of an electroless-plated Cu electrode was investigated as a function of bath composition. To enhance the selectivity of Cu electrode deposition on the surface of an indium tin oxide layer, a Ti/Cu multi-layer was deposited as a Cu electrode seed layer by physical vapor deposition, and then electroless plating was performed using various complexing agents and a surfactant. The degree of selectivity was effectively influenced by the type of complexing agent. The electroless plating solution containing N,N,N′,N′-tetrakis(2-hydroxypropyl)ethylenediamine (THPED) as complexing agent showed excellent selective growth of the Cu electrode as compared to the solution containing ethylenediaminetetraacetic acid. Even though THPED led to better selective growth of the electroless-plated Cu electrode, the aspect ratio of electrode lateral growth was about 2.7 times that of vertical growth. By adding a nonionic surfactant, the ratio between vertical growth rate and lateral growth rate was improved about 4.6 times. The Cu–THPED electroless plating with nonionic surfactant provided a drastic decrease in lateral growth rate, compared with the Cu–THPED electroless plating bath excluding nonionic surfactant. The Cu–THPED solution including nonionic surfactant is a promising composition of electroless plating solution for the clear selective plating of Cu electrodes on hetero-junctions with intrinsic thin layer solar cells. - Highlights: • Selective electroless plating (SEP) depends on binding strength of complexing agent. • The SEP was performed using Cu-N,N,N′,N′-tetrakis(2-hydroxypropyl)ethylenediamine. • A surfactant is able to remove hydrogen bubbles on Cu electrode surface. • The growth of Cu electrode was improved in vertical direction by adding surfactant.

  10. Electroless Plating of Thin Silver Films on Porous Al2O3 Substrate and the Study of Deposition Kinetics

    Institute of Scientific and Technical Information of China (English)

    Fang Mei; Donglu Shi

    2005-01-01

    A novel concept has been developed to coat the inner pore surfaces of reticulated alumina with a thin silver film by an electroless-plating method. As a result of coating, the porous alumina sample exhibits a sharp transition from insulating to conducting due to a thin silver layer on the inner pore surfaces. Systematic studies have been carried out to investigate the coating kinetics by employment of scanning electron microscope (SEM), X-ray diffraction (XRD), and computer simulation. Both coating procedures and effects of processing parameters on the quality of films are reported. Also, this paper presents the film bonding strength to the substrate, effects of sintering, and conduction mechanism of coated composite. The fundamental silver electroless-plating mechanism has been identified based on computer modeling. The simulation results indicate an excellent agreement between the silver deposition behavior and the physical model applied.

  11. The study of electroless Ni-W-P alloy plating on glass fibers

    Institute of Scientific and Technical Information of China (English)

    HUANG Ying; HUANG Fei; ZHAO Wentao; SHI Ke; ZHAO Li; WANG Yanli

    2007-01-01

    Ni-W-P coatings were deposited on the surface of glass fibers by the electroless plating process. The bath was very stable through the palladium salt test. There was no phenomenon of peeling and blistering on the surface of the Ni-W-P alloy glass fibers in the thermal shock test. It showed that the deposit had high impact strength and good adhesion. The morphology of the coatings was observed by scanning electron microscope (SEM). The elements and their contents were tested and analyzed by energy dispersion spectrometer (EDS). The tungsten content reached up to 12.1 wt.%. The effects of results indicated that the deposit had an amorphous structure and good heat stability. The suitable work temperature range was lower than 190℃. Finally, the electromagnetic parameters of the Ni-W-P alloy glass fibers were tested and analyzed primarily. The magnetic loss reached 0.04023 and the dielectric loss reached -5.80239. The plated alloy is a kind of soft magnetic material.

  12. Electroless plating of silver nanoparticles on porous silicon for laser desorption/ionization mass spectrometry

    Science.gov (United States)

    Yan, Hong; Xu, Ning; Huang, Wen-Yi; Han, Huan-Mei; Xiao, Shou-Jun

    2009-03-01

    An improved DIOS (desorption ionization on porous silicon) method for laser desorption/ionization mass spectrometry (LDI MS) by electroless plating of silver nanoparticles (AgNPs) on porous silicon (PSi) was developed. By addition of 4-aminothiophenol (4-ATP) into the AgNO3 plating solution, the plating speed can be slowed down and simultaneously 4-ATP self-assembled monolayers (SAMs) on AgNPs (4-ATP/AgNPs) were formed. Both AgNPs and 4-ATP/AgNPs coated PSi substrates present much higher stability, sensitivity and reproducibility for LDI MS than the un-treated porous silicon ones. Their shelf life in air was tested for several weeks to a month and their mass spectra still displayed the same high quality and sensitivity as the freshly prepared ones. And more 4-ATP SAMs partly play a role of matrix to increase the ionization efficiency. A small organic molecule of tetrapyridinporphyrin (TPyP), oligomers of polyethylene glycol (PEG 400 and 2300), and a peptide of oxytocin were used as examples to demonstrate the feasibility of the silver-plated PSi as a matrix-free-like method for LDI MS. This approach can obtain limits of detection to femtomoles for TPyP, subpicomoles for oxytocin, and picomoles for PEG 400 and 2300, comparable to the traditional matrix method and much better than the DIOS method. It simplifies the sample preparation as a matrix-free-like method without addition of matrix molecules and homogenizes the sample spread over the spot for better and more even mass signals.

  13. PREPARATION OF MICROWAVE ABSORBING NICKEL-BASED ACTIVATED CARBON BY ELECTROLESS PLATING WITH PALLADIUM-FREE ACTIVATION

    OpenAIRE

    Boyang Jia; Lijuan Wang

    2010-01-01

    Nickel-based activated carbon was prepared from coconut shell activated carbon by electroless plating with palladium-free activation. The materials were characterized by scanning electron microscopy (SEM), X-ray energy dispersion spectroscopy (EDS), vibrating sample magnetometry (VSM), and vector network analyzer, respectively. The results show that the surface of the activated carbon was covered by a Ni-P coating, which was uniform, compact, and continuous and had an obvious metallic sheen. ...

  14. The Microstructure and Thermal Conductivity of Pressureless Infiltrated SiCp/Al Composites Containing Electroless Nickel Platings

    OpenAIRE

    Aihua Zou; Xianliang Zhou; Xiaozhen Hua; Duosheng Li; Kaiyang Wu

    2015-01-01

    A nickel (Ni) coating was deposited on the surface of silicon carbide particles (SiCp) through electroless plating and we characterized the morphology and phase structure of the coating and the pressureless infiltrated SiCp/Al composites. The effect of Ni coatings on the thermal conductivity of the composites was examined and analyzed with three-dimensional video microscope, scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction microscope (XRD), and...

  15. Corrosion and wear properties of electroless Ni-P plating layer on AZ91D magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    LI Zhong-hou; CHEN Zhi-yong; LIU Sha-sha; ZHENG Feng; DAI A-gan

    2008-01-01

    A direct electroless Ni-P plating treatment was applied to AZ91D magnesium alloy for improving its corrosion resistance and wear resistance. Corrosion resistance of the Ni-P coatings was evaluated by potentiodynamic polarization and immersing experiments in 3.5% NaCl solution. The wear resistance of the coatings was investigated by the wear track and the mass change after ball-on-disk experiment. The results show that corrosion resistance and wear resistance of the AZ91D alloy are greatly improved after direct electroless Ni-P plating. No discoloration is noticed until 4 d of immersion in 3.5% NaCl solution. Potentiodynamic polarization experiments show that the free corrosion potential of magnesium alloy is shifted from -1 500 mV to -250 mV and passivation occurs at 1 350 mV after direct electroless plating. The friction coefficients and wear rates of Ni-P coating and Ni-P coating after tempering are 0.10-0.351, 9.038×10-3 mm3/m and 0.13-0.177, 3.056×10-4 mm3/m, respectively, at a load of 1.5 N with dry sliding. Although minor hurt on corrosion resistance was caused, significant improvement of wear resistance was obtained after tempering treatment of the coating.

  16. 镁合金化学镀镍层的生长过程%Deposition process of electroless nickel plating on magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    邵忠财; 李建中; 康凤娣; 田彦文

    2005-01-01

    The initial nickel deposition for the direct electroless nickel plating on non-catalytically active magnesium alloy is critical. The surface morphology and composition of the initial nickel plating coating are obtained by means of the scanning electron microscopy (SEM) and the energy dispersive X-ray (EDS). In addition, the mass gain/loss in the initial nickel deposition process was measured by using the electrobalance. The results showed that the MgO coating was gradually corroded by the plating solution, at the same time, MgF2 produced by F , H+ and MgO was deposited on the substrate during the initial electroless plating process. The nickel of the initial electroless plating was mostly growing on the boundary between the MgF2 coating and the MgO coating of the activation substrate, and then came to two sides. After that, the Ni-P coating growth rate to cover with the MgF2 coating was prior to the MgO coating. The electroless plating was in company with the substrate corrosion, but the electroless plating rate catalyzed by the exchanged nickel was more than the substrate corrosion rate.

  17. Copper-Ti3SiC2 composite powder prepared by electroless plating under ultrasonic environment

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhongbao; XU Shaofan

    2007-01-01

    In this article, a new type of Cu-Ti3SiC2 composite powder prepared using the electroless plating technique was introduced. The initial Ti3SiC2 particles are 11 μm in diameter on an average. The Cu plating was carried out at middle temperature (62-65 ℃) with the application of ultrasonic agitation. The copper deposition rate was determined by measuring the weight gain of the powder after plating. It has been found that the pretreatment of Ti3SiC2 powder is very important to obtain copper nanoparticles on the surface of Ti3SiC2. The optimum procedure before plating aimed to add activated sites and the adjustment of the tradifonal composition of the electroless copper plating bath could decelerate the copper deposition rate to 0.8 μm/h. X-ray diffraction (XRD) indicates that the chemical composition of the plating layer is copper. SEM images show that the surface of the Ti3SiC2 particles is successfully coated with continuous copper layer. The wetting property between the copper matrix and Ti3SiC2 can be improved so as to increase the interfacial strength.

  18. Removal of nickel from spent electroless nickel-plating bath with nickel foam cathode

    Institute of Scientific and Technical Information of China (English)

    于秀娟; 郑彤; 魏杰; 周定

    2002-01-01

    The electrochemical method was used to remove nickel ion from spent electroless nickel plating bath(pH = 5.3). An electrolytic cell was composed of a porous nickel foam cathode and an inert RuO2/Ti anode.Nickel ions were reduced and deposited on the surface of the nickel foam cathode. The effect of current density(i), linear velocity of wastewater (v), gap between cathode and anode (dc/A) and reaction time (t) on nickelremoval rate and current efficiency were studied. As reaction time prolonged, nickel removal rate increasedwhile current efficiency decreased. And larger v and smaller dc/A can enhance nickel removal rate and increasecurrent efficiency by promoting mass transfer and dropping concentration polarization. The effect of current den-sity on nickel removal by electrochemistry was related to other parameters. After three hours' electrolysis withi = 1.0 A/dm2, v = 18.5 cm/min and dc/A = 0. 5 cm, nickel removal rate and current efficiency reached85.6% and 29. 1%, respectively.

  19. Reclaim nickel and remove organics from the spent electroless nickel-plating bath by electrolysis

    Institute of Scientific and Technical Information of China (English)

    YU Xiu-juan; SHEN Jin; MENG Xian-lin; LI Shu-qin; YAN Lei; ZHOU Ding

    2006-01-01

    Typical wastes from nickel plating operations include excess drag-out solution. An electrochemical approach was made to recover the nickel and remove the organic pollutants from the spent electroless nickelplating bath. An electrolyte cell which was constructed by the cathode of porous nickel foam and the anode of Ti/RuO2 was used. During electrolysis, the nickel ion was electrodeposited at the cathode and the oxidation of the organics in the bath was conducted at the anode. The current ( i), time ( t), temperature (T) and pH of the solution affected the recovery efficiency of nickel with constant potential electrolysis. With the optimum experimental conditions of pH = 7. 6, i = 0.45 A, T = 65℃ and t = 2 h, the concentration of nickel ion was reduced from 2. 09 g/L to 0. 053 g/L and the recovery rate of nickel, the current efficiency and the consumed energy were 97.5%, 17.1%, 12.2 kWh/kg Ni, respectively. Meanwhile, total organic carbon (TOC) of the bath was reduced from 5 800 mg/L to 152. 5 mg/L and the removal efficiency of TOC was 97.3%. The recovery rate of nickel could keep to about 97% when electrodeposit was used to recover nickel for 40 hours in a laboratory batch reactor containing the spent bath. Dull nickel containing phosphorus was obtained on the cathode.

  20. Electroless plating preparation and electromagnetic properties of Co-coated carbonyl iron particles/polyimide composite

    Science.gov (United States)

    Zhou, Yingying; Zhou, Wancheng; Li, Rong; Qing, Yuchang; Luo, Fa; Zhu, Dongmei

    2016-03-01

    To solve the serious electromagnetic interference problems at elevated temperature, one thin microwave-absorbing sheet employing Co-coated carbonyl iron particles and polyimide was prepared. The Co-coated carbonyl iron particles were successfully prepared using an electroless plating method. The microstructure, composition, phase and static magnetic properties of Co-coated carbonyl iron particles were characterized by combination of scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). The electromagnetic parameters of Co-coated carbonyl iron particles/polyimide composite were measured in the frequency range of 2-18 GHz, and the electromagnetic loss mechanism of the material-obtained was discussed. The microwave absorption properties of composites before and after heat treatment at 300 °C for 100 h were characterized in 2-18 GHz frequency range. It was established that composites based on Co-coated carbonyl iron demonstrate thermomagnetic stability, indicating that Co coating reduces the oxidation of carbonyl iron. Thus, Co-coated carbonyl iron particles/polyimide composites are useful in the design of microwave absorbers operating at temperatures up to 300 °C.

  1. Preparation, characterization and wear behavior of carbon coated magnesium alloy with electroless plating nickel interlayer

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Yan [Shanghai Key Laboratory of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Li, Zhuguo, E-mail: lizg@sjtu.edu.cn [Shanghai Key Laboratory of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Academician Expert Office Workstation (Jiansheng Pan), Lin’an, Zhejiang Province (China); Feng, Kai, E-mail: fengkai@sjtu.edu.cn [Shanghai Key Laboratory of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Academician Expert Office Workstation (Jiansheng Pan), Lin’an, Zhejiang Province (China); Guo, Xingwu [National Engineering Research Center of Light Alloys Net Forming (LAF), School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Zhou, Zhifeng [Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong (China); Dong, Jie [National Engineering Research Center of Light Alloys Net Forming (LAF), School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Wu, Yixiong [Shanghai Key Laboratory of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240 (China); Academician Expert Office Workstation (Jiansheng Pan), Lin’an, Zhejiang Province (China)

    2015-02-01

    Highlights: • The carbon film with nickel interlayer (Ni + C coating) is deposited on GW83. • In Ni + C composite coating the carbon coating has good adhesion with the nickel interlayer. • The wear track of Ni + C coating is narrower compared to the bare one. • The wear resistance of GW83 is greatly improved by the Ni + C coating. - Abstract: Poor wear resistance of rare earth magnesium alloys has prevented them from wider application. In this study, composite coating (PVD carbon coating deposited on electroless plating nickel interlayer) is prepared to protect GW83 magnesium alloys against wear. The Ni + C composite coating has a dense microstructure, improved adhesion strength and hardness due to the effective support of Ni interlayer. The wear test result shows that the Ni + C composite coating can greatly prolong the wear life of the magnesium alloy. The wear track of the Ni + C coated magnesium alloy is obviously narrower and shows less abrasive particles as compared with the bare one. Abrasive wear is the wear mechanism of the coatings at the room temperature. In conclusion, the wear resistance of the GW83 magnesium alloy can be greatly improved by the Ni + C composite coating.

  2. Electrical resistivity and dielectric properties of helical microorganism cells coated with silver by electroless plating

    International Nuclear Information System (INIS)

    Highlights: ► We use the microorganism cells as forming templates to fabricate the bio-based conductive particles. ► The microorganism cells selected as forming templates are Spirulina platens, which are of natural helical shape and high aspect ratio. ► The sliver-coated Spirulina cells are a kind of lightweight conductive particles. ► The composites containing sliver-coated Spirulina cells exhibit a lower percolation value. - Abstract: In this paper, microorganism cells (Spirulina platens) were used as forming templates for the fabrication of the helical functional particles by electroless silver plating process. The morphologies and ingredients of the coated Spirulina cells were analyzed with scanning electron microscopy and energy dispersive spectrometer. The crystal structures were characterized by employing the X-ray diffraction. The electrical resistivity and dielectric properties of samples containing different volume faction of sliver-coated Spirulina cells were measured and investigated by four-probe meter and vector network analyzer. The results showed that the Spirulina cells were successfully coated with a uniform silver coating and their initial helical shapes were perfectly kept. The electrical resistivity and dielectric properties of the samples had a strong dependence on the volume content of sliver-coated Spirulina cells and the samples could achieve a low percolation value owing to high aspect ratio and preferable helical shape of Spirulina cells. Furthermore, the conductive mechanism was analyzed with the classic percolation theory, and the values of φc and t were obtained.

  3. Electroless plating of ultrathin palladium films: self-initiated deposition and application in microreactor fabrication

    Science.gov (United States)

    Muench, Falk; Oezaslan, Mehtap; Svoboda, Ingrid; Ensinger, Wolfgang

    2015-10-01

    We present new electroless palladium plating reactions, which can be applied to complex-shaped substrates and lead to homogeneous, dense and conformal palladium films consisting of small nanoparticles. Notably, autocatalytic and surface-selective metal deposition could be achieved on a wide range of materials without sensitization and activation pretreatments. This provides a facile and competitive route to directly deposit well-defined palladium nanofilms on e.g. carbon, paper, polymers or glass substrates. The reactions proceed at mild conditions and are based on easily accessible chemicals (reducing agent: hydrazine; metal source: PdCl2; ligands: ethylenediaminetetraacetic acid (EDTA), acetylacetone). Additionally, the water-soluble capping agent 4-dimethylaminopyridine (DMAP) is employed to increase the bath stability, to ensure the formation of small particles and to improve the film conformity. The great potential of the outlined reactions for micro- and nanofabrication is demonstrated by coating an ion-track etched polycarbonate membrane with a uniform Pd film of approximately 20 nm thickness. The as-prepared membrane is then employed as a highly miniaturized flow reactor, using the reduction of 4-nitrophenol with NaBH4 as a model reaction.

  4. Fabrication and microwave properties of hollow nickel spheres prepared by electroless plating and template corrosion method

    International Nuclear Information System (INIS)

    Using carbonyl iron as template, hollow nickel spheres were prepared by electroless plating on carbonyl iron and template corrosion method. The samples were characterized by X-ray diffraction (XRD), X-ray fluorescence spectrometer (XRF), transmission electron microscope (TEM), scanning electron microscope (SEM), vibrating sample magnetometer (VSM) and vector network analyzer. Results showed that the shell thickness can be controlled by adjusting the loadage of carbonyl iron templates. The hollow nickel spheres exhibited good magnetic properties with a saturation magnetization of 48.56 emu/g and enhanced coercivity (as high as 260 Oe). The real (ε′) and imaginary (ε″) parts of complex permittivity of hollow nickel spheres first increased and then decreased as the shell thickness increased, and the sample with the thinnest shell showed the lowest complex permittivity. For the complex permeability, the resonance peak shifted to the lower frequency and then moved to higher frequency, as the shell thickness increased. The microwave absorption performances could be tuned by changing the shell thickness. In this study, the minimum reflection loss (RL) value of −27.2 dB was obtained at 13.4 GHz with a matching thickness of 1.4 mm and the effective absorption band (RL <−5 dB) from 11.8 to 18 GHz, covering the whole Ku-band (12.4−18 GHz).

  5. Microwire formation based on dielectrophoresis of electroless gold plated polystyrene microspheres

    International Nuclear Information System (INIS)

    Microspheres coated with a perfectly conductive surface have many advantages in the applications of biosensors and micro-electromechanical systems. Polystyrene microspheres with the diameter of 10 μm were coated with a 50 nm-thick gold layer using an electroless gold plating approach. Dielectrophoresis (DEP) for bare microspheres and shelled microspheres was theoretically analysed and the real part of the Clausius—Mossotti factor was calculated for the two kinds of microspheres. The experiments on the dielectrophoretic characterisation of the uncoated polystyrene microspheres and gold coated polystyrene microspheres (GCPMs) were carried out. Experimental results showed that the gold coated polystyrene microspheres were only acted by a positive dielectrophoretic force when the frequency was below 40M Hz, while the uncoated polystyrene microspheres were governed by a negative dielectrophoretic force in this frequency range. The gold coated polystyrene microspheres were exploited to form the microwire automatically according to their stable dielectrophoretic and electric characterisations. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  6. A polydopamine-modified optical fiber SPR biosensor using electroless-plated gold films for immunoassays.

    Science.gov (United States)

    Shi, Se; Wang, Libing; Su, Rongxin; Liu, Boshi; Huang, Renliang; Qi, Wei; He, Zhimin

    2015-12-15

    A sensitive and stable electroless-plated gold film for the preparation of an optical fiber surface plasmon resonance (SPR) sensor is presented in this work, together with a facile antibody immobilization method. Gold nanoparticles were uniformly adsorbed onto the surface of an optical fiber forming a film with a thickness of approximately 56.3 nm. The sensor had a high sensitivity with 2054 nm/RIU and 3980 nm/RIU in the refractive index ranges of 1.333-1.359 and 1.359-1.386, respectively. An SPR biosensor was developed based on polydopamine-modified gold film (PDA-Au), which was fabricated by a simple and quick spontaneous polymerization of dopamine (DA) on the gold film. When goat anti-human IgG antibodies were immobilized, the PDA-Au surface had a larger resonant wavelength shift of 66.21 nm compared with the traditional 11-mercaptoundecanoic acid-modified gold film (MUA-Au) surface. In addition, the PDA-Au surface enabled the sensitive and selective determination of human IgG down to a concentration of 2 μg mL(-1) with a high sensitivity of 0.41 nm per μg mL(-1). The PDA-Au surface exhibited an approximately four fold higher sensitivity and an about seven fold lower LOD than the MUA-Au surface to human IgG. PMID:26164491

  7. Structural Characterization and Mechanical Properties of As-plated and Heat Treated Electroless Ni-B-P Alloy Coatings

    OpenAIRE

    P. G. Venkatakrishnan; S. S. Mohamed Nazirudeen; T.S.N. Sankara Narayanan

    2014-01-01

    The Ni-B-P alloy coatings were made autocatalytically (electroless) using an alkaline plating bath with nickel chloride hexahydrate (NiCl2.6H2O) as the source of nickel ions, sodium borohydride (NaBH4) and sodium hypophosphite (NaH2PO2) as reducing agents and source of boron and phosphorous ions, respectively. The effects of bath concentrations on the plating rate, composition of coating, surface morphology, structural features and microhardness have been studied by varying NaBH4 concentra...

  8. Structural Characterization and Mechanical Properties of As-plated and Heat Treated Electroless Ni-B-P Alloy Coatings

    Directory of Open Access Journals (Sweden)

    P. G. Venkatakrishnan

    2014-05-01

    Full Text Available The Ni-B-P alloy coatings were made autocatalytically (electroless using an alkaline plating bath with nickel chloride hexahydrate (NiCl2.6H2O as the source of nickel ions, sodium borohydride (NaBH4 and sodium hypophosphite (NaH2PO2 as reducing agents and source of boron and phosphorous ions, respectively. The effects of bath concentrations on the plating rate, composition of coating, surface morphology, structural features and microhardness have been studied by varying NaBH4 concentration in the plating bath from 0.2 to 0.8 g/l while keeping NaH2PO2 concentration constant (12 g/l. The plating rate and boron content of the electroless Ni-B-P ternary alloy coatings increased with increasing NaBH4 concentration in the plating bath. The scanning electron microscopic images revealed that the morphology of the coating changed from corn cob structure to coarse cauliflower structure with increasing borohydride concentration in the plating bath. Broadening of X-ray diffraction peak is observed, as the borohydride concentration is increased in the plating bath, which is attributed to the large reduction in the crystallite size of the Ni-B-P alloy coatings. The microhardness values of the coating increased with increasing borohydride concentration in the plating bath. The as-plated Ni-B-P alloy coating containing higher boron content (3.2 wt% shows higher hardness of 700 HV compared to other Ni-B-P alloy coatings. The XRD patterns of heat treated Ni-B-P alloy coatings (500 °C show Ni3B intermetallic peaks along with Ni peaks. The presence of Ni3B intermetallic compound significantly increases the microhardness values of the heat treated Ni-B-P alloy coatings.

  9. Electrical resistivity and dielectric properties of helical microorganism cells coated with silver by electroless plating

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Jun, E-mail: jun_cai@buaa.edu.cn [Bionic and Micro/Nano/Bio Manufacturing Technology Research Center, School of Mechanical Engineering and Automation, Beihang University, Beijing 100191 (China); Lan, Mingming; Zhang, Deyuan; Zhang, Wenqiang [Bionic and Micro/Nano/Bio Manufacturing Technology Research Center, School of Mechanical Engineering and Automation, Beihang University, Beijing 100191 (China)

    2012-09-01

    Highlights: Black-Right-Pointing-Pointer We use the microorganism cells as forming templates to fabricate the bio-based conductive particles. Black-Right-Pointing-Pointer The microorganism cells selected as forming templates are Spirulina platens, which are of natural helical shape and high aspect ratio. Black-Right-Pointing-Pointer The sliver-coated Spirulina cells are a kind of lightweight conductive particles. Black-Right-Pointing-Pointer The composites containing sliver-coated Spirulina cells exhibit a lower percolation value. - Abstract: In this paper, microorganism cells (Spirulina platens) were used as forming templates for the fabrication of the helical functional particles by electroless silver plating process. The morphologies and ingredients of the coated Spirulina cells were analyzed with scanning electron microscopy and energy dispersive spectrometer. The crystal structures were characterized by employing the X-ray diffraction. The electrical resistivity and dielectric properties of samples containing different volume faction of sliver-coated Spirulina cells were measured and investigated by four-probe meter and vector network analyzer. The results showed that the Spirulina cells were successfully coated with a uniform silver coating and their initial helical shapes were perfectly kept. The electrical resistivity and dielectric properties of the samples had a strong dependence on the volume content of sliver-coated Spirulina cells and the samples could achieve a low percolation value owing to high aspect ratio and preferable helical shape of Spirulina cells. Furthermore, the conductive mechanism was analyzed with the classic percolation theory, and the values of {phi}{sub c} and t were obtained.

  10. Development of Microelectrode Arrays Using Electroless Plating for CMOS-Based Direct Counting of Bacterial and HeLa Cells.

    Science.gov (United States)

    Niitsu, Kiichi; Ota, Shoko; Gamo, Kohei; Kondo, Hiroki; Hori, Masaru; Nakazato, Kazuo

    2015-10-01

    The development of two new types of high-density, electroless plated microelectrode arrays for CMOS-based high-sensitivity direct bacteria and HeLa cell counting are presented. For emerging high-sensitivity direct pathogen counting, two technical challenges must be addressed. One is the formation of a bacteria-sized microelectrode, and the other is the development of a high-sensitivity and high-speed amperometry circuit. The requirement for microelectrode formation is that the gold microelectrodes are required to be as small as the target cell. By improving a self-aligned electroless plating technique, the dimensions of the microelectrodes on a CMOS sensor chip in this work were successfully reduced to 1.2 μm × 2.05 μm. This is 1/20th of the smallest size reported in the literature. Since a bacteria-sized microelectrode has a severe limitation on the current flow, the amperometry circuit has to have a high sensitivity and high speed with low noise. In this work, a current buffer was inserted to mitigate the potential fluctuation. Three test chips were fabricated using a 0.6- μm CMOS process: two with 1.2 μm × 2.05 μm (1024 × 1024 and 4 × 4) sensor arrays and one with 6- μm square (16 × 16) sensor arrays; and the microelectrodes were formed on them using electroless plating. The uniformity among the 1024 × 1024 electrodes arranged with a pitch of 3.6 μm × 4.45 μm was optically verified. For improving sensitivity, the trenches on each microelectrode were developed and verified optically and electrochemically for the first time. Higher sensitivity can be achieved by introducing a trench structure than by using a conventional microelectrode formed by contact photolithography. Cyclic voltammetry (CV) measurements obtained using the 1.2 μm × 2.05 μm 4 × 4 and 6- μm square 16 × 16 sensor array with electroless-plated microelectrodes successfully demonstrated direct counting of the bacteria-sized microbeads and HeLa cells. PMID:26561481

  11. Preparation and Magnetic Properties of Anisotropic (Sm,Pr)Co5/Fe Nanocomposites Particles via Electroless Plating

    OpenAIRE

    Shi Wang; Jin-Ming Ma; Yan Chen

    2014-01-01

    Anisotropic (Sm,Pr)Co5/Fe nanocomposites particles were prepared by electroless plating iron on the surface of (Sm,Pr)Co5 nanoflakes after being prepared by ball milling for 4 h. A uniform and continuous coating layer was obtained due to the addition of complexing agent and the particle size of the reduced Fe particles was in the range of 10~20 nm. When the nominal addition of Fe was 15 wt%, the nanocomposites show enhanced remnant and saturation magnetization: Mr=53.35 emu/g, Ms=73.08 emu/g ...

  12. Nickel-niobium alloy formation process of electroless nickel composite plating film using niobium nano-power

    International Nuclear Information System (INIS)

    Composite plating improves functionalities of wear resistance, corrosion resistance, lubricity, etc. through co-deposition with suitable particles. For this study, reactive metallic particles were introduced intentionally as a dispersant. Heat treatment was used to form an alloy with a plated matrix. Composite plating films were formed using electroless Ni-P plating with Nb powder of two types as dispersants: nanopowder (ca. 300 nm diameter) and micropowder (ca. 50 μm diameter). The composite plating film was alloyed using heat treatment at 800degC for 1 hour under vacuum conditions. X-ray diffraction (XRD) analysis confirmed that the proportion of alloy to reactive composite film with nanopowder was much larger than that with micropowder. Results of X-ray photoelectron spectroscopy (XPS) analyses suggest that a selective Nb oxide was formed on the composite film surface when using Nb nanopowder. On the other hand, almost no Nb micropowder was changed to alloy or oxide in the composite films. Using nanopowder, much of the composite plating film formed reactive composite plating film alloy during heat treatment. (author)

  13. Enhanced antioxidation and electromagnetic properties of Co-coated flaky carbonyl iron particles prepared by electroless plating

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Yingying, E-mail: zyzlchappy1989@163.com [State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an, Shaanxi 710072 (China); Zhou, Wancheng [State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an, Shaanxi 710072 (China); Li, Rong [State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an, Shaanxi 710072 (China); No. 603 Faculty, Xi’an Institute of High Technology, Xi’an 710025 (China); Mu, Yang; Qing, Yuchang [State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an, Shaanxi 710072 (China)

    2015-07-15

    Highlights: • Co-coated carbonyl iron particles were prepared by electroless plating method. • The obvious weight gain of carbonyl iron was deferred to 400 °C after Co-coated. • The permeability of the Co-coated particle composite kept almost invariable. • Co-coated carbonyl iron composite reserves a better absorption after heat treatment. - Abstract: Co was successfully coated on the surface of flaky carbonyl iron particles using an electroless plating method. The morphologies, composition, as well as magnetic, antioxidation and electromagnetic properties of the samples were characterized by scanning electron microscope (SEM), energy dispersive spectrometer (EDS), vibrating sample magnetometer (VSM), thermogravimetric (TG) and microwave network analyzer. TG curve shows that the obvious weight gain of carbonyl iron was deferred from 300 to 400 °C after Co-coated. In contrast to raw carbonyl iron, the Co-coated carbonyl iron shows better stability on electromagnetic properties after 300 °C heat treatment for 10 h, demonstrating that the Co coating can act as the protection of carbonyl iron.

  14. Fabrication of Pd/Pd-Alloy Films by Surfactant Induced Electroless Plating for Hydrogen Separation from Advanced Coal Gasification Processes

    Energy Technology Data Exchange (ETDEWEB)

    Ilias, Shamsuddin; Kumar, Dhananjay

    2012-07-31

    Dense Pd, Pd-Cu and Pd-Ag composite membranes on microporous stainless steel substrate (MPSS) were fabricated by a novel electroless plating (EP) process. In the conventional Pd-EP process, the oxidation-reduction reactions between Pd-complex and hydrazine result in an evolution of NH{sub 3} and N{sub 2} gas bubbles. When adhered to the substrate surface and in the pores, these gas bubbles hinder uniform Pd-film deposition which results in dendrite growth leading to poor film formation. This problem was addressed by introducing cationic surfactant in the electroless plating process known as surfactant induced electroless plating (SIEP). The unique features of this innovation provide control of Pd-deposition rate, and Pd-grain size distribution. The surfactant molecules play an important role in the EP process by tailoring grain size and the process of agglomeration by removing tiny gas bubbles through adsorption at the gas-liquid interface. As a result surfactant can tailor a nanocrystalline Pd, Cu and Ag deposition in the film resulting in reduced membrane film thickness. Also, it produces a uniform, agglomerated film structure. The Pd-Cu and Pd-Ag membranes on MPSS support were fabricated by sequential deposition using SIEP method. The pre- and post-annealing characterizations of these membranes (Pd, Pd-Cu and Pd-Ag on MPSS substrate) were carried out by SEM, EDX, XRD, and AFM studies. The SEM images show significant improvement of the membrane surface morphology, in terms of metal grain structures and grain agglomeration compared to the membranes fabricated by conventional EP process. The SEM images and helium gas-tightness studies indicate that dense and thinner films of Pd, Pd-Cu and Pd-Ag membranes can be produced with shorter deposition time using surfactant. H{sub 2} Flux through the membranes fabricated by SIEP shows large improvement compared to those by CEP with comparable permselectivity. Pd-MPSS composite membrane was subjected to test for long term

  15. Effect of 2,2‧-dipyridyl on the plating rate, microstructure and performance of copper-coated tungsten composite powders prepared using electroless plating

    Science.gov (United States)

    Chen, Wenshu; Luo, Guoqiang; Li, Meijuan; Shen, Qiang; Wang, Chuanbin; Zhang, Lianmeng

    2014-05-01

    Highly pure copper-coated tungsten powders were successfully prepared in fixed quantities using electroless plating, via the addition of an appropriate amount of 2,2‧-dipyridyl to the plating bath. The effect of 2,2‧-dipyridyl on the plating Cu rate, microstructure and performance of the coated Cu layer was studied systematically. Changing the concentration of 2,2‧-dipyridyl had significant effects on the plating Cu rate, surface morphology, average grain size, purity and quantity of coated Cu. With a 2,2‧-dipyridyl concentration of approximately 20-40 mg/L, the coated Cu was highly pure, with very little oxygen content (less than 0.1 wt.%). The complexation of the 2,2‧-dipyridyl with cuprous ions and the absorption of the 2,2‧-dipyridyl on the coated Cu surface can explain these findings. With increase in the concentration of 2,2‧-dipyridyl in the plating bath, the plating Cu rate, microstructure and performance of the coated Cu layer changed steadily, indicating that the complexation and absorption of 2,2‧-dipyridyl gradually approached a saturation level. High thermal performance W-Cu composite can be fabricated by using these composite powders.

  16. 化学镀可焊性锡基合金的研究进展%Progress of research on electroless plating of solderable tin alloy

    Institute of Scientific and Technical Information of China (English)

    赵国鹏; 樊江莉; 温青

    2001-01-01

    本文综述了近10年来化学镀可焊性锡基合金的研究现状及动态。列举了4种不同镀液体系的典型配方及工艺,并对化学镀锡合金的未来发展提出了建议。%Current status and prospect of solderable electroless tin alloy plating were summarized with 18 references published in the recent decade. Four traditional plating solutions based on chloride, fluoboric, alkyl sulfonate and ethane sulfonate were exemplified. Suggestions were presented about the develoment of electroless plating of solderable tin alloy.

  17. Effects of Hard Surface Grinding and Activation on Electroless-Nickel Plating on Cast Aluminium Alloy Substrates

    Directory of Open Access Journals (Sweden)

    Olawale Olarewaju Ajibola

    2014-01-01

    Full Text Available This work examined effects of hard surface polishing grits and activation on electroless-nickel (EN plating on cast aluminium alloy substrates in sodium hypophosphite baths. As-received aluminium alloy sample sourced from automobile hydraulic brake master cylinder piston was melted in electric furnace and sand cast into rod. The cast samples were polished using different grits (60 μm–1200 μm before plating. The effects on adhesion, appearance, and quantity of EN deposits on substrates were studied. Observation shows that the quantity of EN deposit is partly dependent on the alloy type and roughness of the surface of the substrates, whereas the adhesion and brightness are not solely controlled by the degree of surface polishing. The best yield in terms of adhesion and appearance was obtained from the activation in zincate and palladium chloride solutions. Higher plating rates (g/mm2/min of 3.01E-05, 2.41E-05, and 2.90E-05 were obtained from chromate, zincate, and chloride than 8.49E-06, 8.86E-06, and 1.69E-05 as obtained from HCl etched, NaOH, and H2O activated surfaces, respectively.

  18. Estimation of fatigue evolution of aluminum alloy plated with electroless NI–CO–P by using electromagnetic impedance method

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, Katsuyuki

    2015-02-01

    We have developed a method for detecting fatigue in aluminum alloys that is based on a applying a ferromagnetic electroless Ni–Co–P plating and then using an electromagnetic impedance (EMI) method to determine its permeability properties by measuring the high-frequency AC impedance of a coil sensor in the presence of a static magnetic field. The results obtained confirmed that this method can estimate the fatigue evolution of a specimen until the point at which the cumulative strain becomes saturated by using measurements obtained by the EMI method under tensile deformation and FEM analysis results. - Highlights: • Plating aluminum alloy with Ni–Co–P film increases its fatigue strength by 13−16%. • The tensile direction is the stress induced “hard axis” of the Ni–Co–P plating. • In-plane permeability determines the coil impedance for out-of-plane excitation. • This method can measure fatigue up to saturation of the substrate's residual strain.

  19. Application of Ni-P Alloy Electroless Plating in Rapier Head

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhao-jun; LIU Ying

    2004-01-01

    A way which uses electrcless plating of Ni-P alloy to treat the Al-alloy-rapier head, instead of the import one, is introduced. After analyzing the effect of pretreatment, plating solution formula, plating technique and post heat treatment, a simple and practicable plating and post-heat-treat technique is found out. The performance of the determined plating solution formula is stable. A plating coat thickness more than 40 μm can be obtained. The combination of the plating coat with base is good. The hardness of the coat is above 1100 HV. Its multiple performance is equal to the import one's.

  20. Collection of Ni-bearing material from electroless plating waste by magnetic separation with HTS bulk magnet

    Energy Technology Data Exchange (ETDEWEB)

    Oka, T., E-mail: okat@eng.niigata-u.ac.jp [Niigata University, 8050 Ikarashi-Ninocho, Nishi-ku, Niigata 950-2181 (Japan); Fukazawa, H.; Fukui, S.; Ogawa, J.; Sato, T.; Ooizumi, M. [Niigata University, 8050 Ikarashi-Ninocho, Nishi-ku, Niigata 950-2181 (Japan); Tsujimura, M. [Aichi Giken Co., 50-1 Takeshita, Hitotugi-cho, Kariya, Aichi 448-0003 (Japan); Yokoyama, K. [Ashikaga Institute of Technology, 268-1 Ohmae-cho, Ashikaga, Tochigi 326-8558 (Japan)

    2014-01-15

    Highlights: ► The magnetic separation for Ni compounds was conducted by HTS bulk magnet. ► The coarse Ni-sulfate crystals were formed from the Ni-phosphite precipitates. ► Ni-sulfate crystals was separated from the mixture of Ni-sulfate and Ni-phosphite compounds. -- Abstract: The magnetic separation experiment to collect the Ni compounds from the waste liquid of electroless plating processes was conducted in the open-gradient magnetic separation process with the high temperature superconducting bulk magnet system. The magnetic pole containing Gd-based bulk superconductors was activated to 3.45 T at 35 K in the static magnetic field of 5 T with use of a superconducting solenoid magnet. The coarse Ni-sulfate crystals were formed by adding the concentrated sulfuric acid to the Ni-phosphite precipitates which yielded from the plating waste liquid by controlling the temperature and the pH value. The open-gradient magnetic separation technique was employed to separate the Ni-sulfate crystals from the mixture of the Ni-sulfate and Ni-phosphite compounds by the difference between their magnetic properties. And we succeeded in collecting Ni-sulfate crystals preferentially to the Ni-phosphite by attracting them to the magnetic pole soon after the Ni-sulfate crystals began to grow.

  1. Al/Pb lightweight grids prepared by molten salt electroless plating for application in lead-acid batteries

    Science.gov (United States)

    Hong, Bo; Jiang, Liangxing; Hao, Ketao; Liu, Fangyang; Yu, Xiaoying; Xue, Haitao; Li, Jie; Liu, Yexiang

    2014-06-01

    In this paper, a lightweight Pb plated Al (Al/Pb) grid was prepared by molten salt electroless plating. The SEM and bonding strength test show that the lead coating is deposited with a smooth surface and firm combination. CV test shows that the electrochemical properties of Al/Pb electrodes are stable. 2.0 V single-cell flooded lead-acid batteries with Al/Pb grids as negative collectors are assembled and the performances including 20 h capacity, rate capacity, cycle life, internal resistance are investigated. The results show that the cycle life of Al/Pb-grid cells is about 475 cycles and can meet the requirement of lead-acid batteries. Al/Pb grids are conducive to the refinement of PbSO4 grain, and thereby reduce the internal resistance of battery and advance the utilization of active mass. Moreover, weight of Al/Pb grid is only 55.4% of the conventional-grid. In this way, mass specific capacity of Al/Pb-grid negatives is 17.8% higher and the utilization of active mass is 6.5% higher than conventional-grid negatives.

  2. PREPARATION OF MICROWAVE ABSORBING NICKEL-BASED ACTIVATED CARBON BY ELECTROLESS PLATING WITH PALLADIUM-FREE ACTIVATION

    Directory of Open Access Journals (Sweden)

    Boyang Jia

    2010-08-01

    Full Text Available Nickel-based activated carbon was prepared from coconut shell activated carbon by electroless plating with palladium-free activation. The materials were characterized by scanning electron microscopy (SEM, X-ray energy dispersion spectroscopy (EDS, vibrating sample magnetometry (VSM, and vector network analyzer, respectively. The results show that the surface of the activated carbon was covered by a Ni-P coating, which was uniform, compact, and continuous and had an obvious metallic sheen. The content of P and Ni was 2.73% and 97.27% in the coating. Compared with the untreated activated carbon, the real permeability μ′ and imaginary permeability μ″ of Ni-based activated carbon became greater, whereas the real permittivity ε′ and imaginary permittivity ε″ became smaller. Also, the plated activated carbon was magnetic, making it suitable for some special applications. In general, the method reported here might be a feasible procedure to coat activated carbon with other magnetic metals, which may find application in various areas.

  3. Effects of TiN nanoparticles on the microstructure and properties of W–30Cu composites prepared via electroless plating and powder metallurgy

    International Nuclear Information System (INIS)

    Highlights: • TiN-doped W–Cu composite was successfully prepared by electroless plating and powder metallurgy. • TiN-doped W–Cu significantly affected the microstructure and properties of the composites. • W–Cu composite with 0.25 wt.% TiN possesses the best comprehensive performance. - Abstract: W–30Cu/(0, 0.25, 0.5, 1, and 2) wt.% TiN composites were prepared via electroless plating with simplified pretreatment and powder metallurgy. The phase and morphology of W–Cu/TiN composite powders and sintered W–Cu/TiN samples were characterized via X-ray diffraction and field emission scanning electron microscopy. Transmission electron microscopy was performed to characterize the microstructure of the sintered W–Cu/TiN samples. The relative density, hardness, electrical conductivity, and compressive strength of the sintered samples were examined. Results showed that W–30Cu composite powders with a uniform structure can be obtained using W powder pretreated with nitric acid, ammonium fluoride, and hydrofluoric acid followed by electroless Cu plating. The addition of TiN nanoparticles significantly affected the microstructure and properties of the W–30Cu composites. A good combination of the compressive strength and hardness of the W–30Cu composite material can be obtained by incorporating the TiN additive at 0.25 wt.%. However, the relative density and electrical conductivity slightly decreased

  4. The influence of platinum washing-out time on its recovery from used auto catalytic converters

    Directory of Open Access Journals (Sweden)

    A. Fornalczyk

    2014-07-01

    Full Text Available The used catalytic converters contain small amounts of precious metals. Recovery of these metals is essential for environmental and economic reasons. This work presents a method of Platinum Group Metals (PGM recovery from auto catalytic converters in which they are washed out by a liquid metal. The magneto-hydro-dynamic pump was used to force circulation of liquid metal under the influence of electromagnetic fields The influence of process time on platinum recovery was also carried out.

  5. State of the art on hydrogen passive auto-catalytic recombiner (european union Parsoar project)

    Energy Technology Data Exchange (ETDEWEB)

    Arnould, F.; Bachellerie, E. [Technicatome, 13 - Aix en Provence (France); Auglaire, M. [Tractebel Energy Engineering, Brussels (Belgium); Boeck, B. de [Association Vincotte Nuclear, Brussels (Belgium); Braillard, O. [CEA Cadarache, 13 - Saint Paul lez Durance (France); Eckardt, B. [Siemens AG, Offenbach am Main (Germany); Ferroni, F. [Electrowatt Engineering Limited, Zurich (Switzerland); Moffett, R. [Atomic Energy Canada Limited, Pinawa (Canada); Van Goethem, G. [European Commission, Brussels (Belgium)

    2001-07-01

    This paper presents an overview of the European Union PARSOAR project, which consists in carrying out a state of the art on hydrogen passive auto-catalytic recombiner (PAR) and a handbook guide for implementing these devices in nuclear power plants. This work is performed in the area ''Operational Safety of Existing Installations'' of the key action ''Nuclear Fission'' of the fifth Euratom Framework Programme (1998-2002). (author)

  6. State of the art on hydrogen passive auto-catalytic recombiner (european union Parsoar project)

    International Nuclear Information System (INIS)

    This paper presents an overview of the European Union PARSOAR project, which consists in carrying out a state of the art on hydrogen passive auto-catalytic recombiner (PAR) and a handbook guide for implementing these devices in nuclear power plants. This work is performed in the area ''Operational Safety of Existing Installations'' of the key action ''Nuclear Fission'' of the fifth Euratom Framework Programme (1998-2002). (author)

  7. Structure and Mechanical Properties of Ni-P-Nano Al2O3 Composite Coatings Synthesized by Electroless Plating

    Institute of Scientific and Technical Information of China (English)

    ZHOU Guang-hong; DING Hong-yan; ZHOU Fei; ZHANG Yue

    2008-01-01

    Ni-P-nano Al2O3 composite coatings were deposited by electroless plating, and their microstructures were observed by SEM (scanning electron microscope). The microhardness and the wear resistance of the Ni-P-nano Al2O3 composite coatings were measured using microhardness tester and block-on-ring tribometer, respectively, and the comparison with those of Ni-P coatings or Ni-P-micro Al2O3 coating was given. The influences of aging temperature on their hardness and wear resistance were analyzed. The results showed that the nano Al2O3 particles were distributed uniformly in the Ni-P-Al2O3 coatings. Among three kinds of Ni-P based coatings, the hardness and wear resistance of Ni-P-nano Al2O3 coatings were largest, and the maximum values could be obtained at 400 ℃. This indicated that the precipitation of nano Al2O3 particles would improve the hardness and wear resistance of the Ni-P coatings.

  8. Preparation and Magnetic Properties of Anisotropic (Sm,PrCo5/Fe Nanocomposites Particles via Electroless Plating

    Directory of Open Access Journals (Sweden)

    Shi Wang

    2014-01-01

    Full Text Available Anisotropic (Sm,PrCo5/Fe nanocomposites particles were prepared by electroless plating iron on the surface of (Sm,PrCo5 nanoflakes after being prepared by ball milling for 4 h. A uniform and continuous coating layer was obtained due to the addition of complexing agent and the particle size of the reduced Fe particles was in the range of 10~20 nm. When the nominal addition of Fe was 15 wt%, the nanocomposites show enhanced remnant and saturation magnetization: Mr=53.35 emu/g, Ms=73.08 emu/g compared to the noncoated nanoflakes with Mr=48.52 emu/g, Ms=60.15 emu/g, while the coercivity drops from 10.33 kOe to 8.89 kOe. The effect of Fe content on the magnetic properties of the magnets is also discussed.

  9. The Microstructure and Thermal Conductivity of Pressureless Infiltrated SiCp/Al Composites Containing Electroless Nickel Platings

    Directory of Open Access Journals (Sweden)

    Aihua Zou

    2015-01-01

    Full Text Available A nickel (Ni coating was deposited on the surface of silicon carbide particles (SiCp through electroless plating and we characterized the morphology and phase structure of the coating and the pressureless infiltrated SiCp/Al composites. The effect of Ni coatings on the thermal conductivity of the composites was examined and analyzed with three-dimensional video microscope, scanning electron microscope (SEM, energy-dispersive X-ray spectroscopy (EDS, X-ray diffraction microscope (XRD, and finite-element. The results show that a continuous and uniform coating with a certain thickness (around 3.5 μm can be formed on the surface of SiCp. With the addition of the Ni layer, there are some intermetallics Ni3Al but no interfacial carbide Al4C3, which improves the wettability and the thermal conductivity of the composites. The experiments and simulations both show that Ni coatings do not substantially decrease the overall thermal conductivity of the composite, although the thermal conductivity of Ni itself is lower than Al and SiC by a factor of 1.

  10. NH3 Plasma Surface Treatments of Engineering Fluoropolymers:A Way toEnhance Adhesion of Ni or Cu Thin Films Deposited by Electroless Plating

    Institute of Scientific and Technical Information of China (English)

    Maurice Romand; Marlène Charbonnier; Yves Goepfert

    2004-01-01

    This paper describes the electroless Ni or Cu plating of some fiuoropolymer substrates through a tin-free activation process. Materials subjected to surface metallization are commercial Teflon() FEP, Nafion(), ACLAR() and LaRCTM-CP1 thin films which have recently gained a large scientific and technological interest due to their excellent thermal, chemical, mechanical and dielectric properties. The original approach implemented in the present work involves: (i)the grafting of nitrogen-containing functionalities on the polymer surfaces through plasma treatments in ammonia, (ii) the direct catalysis of the so-modified surfaces via their immersion in a simple acidic PdCl2 solution (i.e. without using a prior surface sensitization in an acidic SnCl2 solution), and finally (iii) the electroless metallization itself. However, prior to the immersion in the industrial plating baths, the chemical reduction of the Pd+2 species (species covalently tethered on the nitrogen-containing groups) to metallic palladium (PdO) is shown to be a key factor in catalyzing the electroless deposition initiation. This is made by immersion in an hypophosphite (H2PO2-) solution. Wettability measurements and X-ray photoelectron spectroscopy (XPS) experiments are used to characterize every surface modification step of the developed process. A cross-hatch tape test was used to asses the adhesion strength of the electroless films that is shown qualitatively good. In addition, a fragmentation test was developed in combination with electrical measurements. Its use allows to distinguish different adhesion levels at the metal/polymer interface and to evidence the influence of some processing parameters.

  11. NH3 Plasma Surface Treatments of Engineering Fluoropolymers: A Way to Enhance Adhesion of Ni or Cu Thin Films Deposited by Electroless Plating

    Institute of Scientific and Technical Information of China (English)

    MauriceRomand; MarleneCharbonnier; YvesGoepfert

    2004-01-01

    This paper describes the electroless Ni or Cu plating of some fluoropolymer substrates through a tin-free activation process. Materials subjected to surface metallization are commercial Teflon FEE Nation, ACLAR and LaRCTM-CP1 thin films which have recently gained a large scientific and technological interest due to their excellent thermal, chemical, mechanical and dielectric properties. The original approach implemented in the present work involves: (i) the grafting of nitrogen-containing functionalities on the polymer surfaces through plasma treatments in ammonia, (ii) the direct catalysis of the so-modified surfaces via their immersion insurface sensitization in an acidic SnCl2 solution), and finally (iii)a simple acidic PdCl2 solution (i.e. without using a prior the electroless metallization itself. However, prior to the immersion in the industrial plating baths, the chemical reduction of the Pd+1 species (species covalently tethered on the nitrogen-containing groups) to metallic palladium (Pd0) is shown to be a key factor in catalyzing the electroless deposition initiation. This is made by immersion in an hypophosphite (H2PO2-) solution. Wettability measurements and X-ray photoelectron spectroscopy (XPS) experiments are used to characterize every surface modification step of the developed process. A cross-hatch tape test was used to asses the adhesion strength of the electroless films that is shown qualitatively good. In addition, a fragmentation test was developed in combination with electrical measurements. Its use allows to distinguish different adhesion levels at the metal/polymer interface and to evidence the influence of some processing parameters.

  12. Effects of Binary Mixture of Yb2O3-La2O3 on Pd/Ag Co-Deposition by Electroless Plating

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The binary mixture of Yb2O3-La2O3 was used as an additive to improve the traditional electroless plating for Pd-Ag co-deposition on the inside surface of a porous ceramic tube. The main attention were paid to investigating the effects of Yb2O3-La2O3 on Pd-Ag co-deposition rate, plating temperature, Ag content in film and Pd/Ag reduction potentials. The experimental results show that the co-deposition rate is increased by 63%, the plating temperature is decreased by 10~20 ℃ for obtaining the same co-deposition rate and the Ag content in film basically remains unchangeable when Yb2O3-La2O3 is added into the traditional electroless plating solution. The experiment also shows that Pd/Ag reduction potentials basically remain unchangeable with the binary rare earths based on the electrochemical mathematical models An inorganic composite membrane with alloy film of 76.8(mol)% Pd-23.2(mol)% Ag and the thickness of 7.7 μm on the porous ceramic tube was prepared and the permeation fluxes of hydrogen and nitrogen through the membrane are 8.65×10-3 and 1.92×10-6 m3·m-2·s-1 at 350 ℃ and 0.3 MPa respectively.

  13. Microstructure and magnetic properties of C/Co-P and Al2O3/Co-P composite particles prepared by electroless plating

    Science.gov (United States)

    Denisova, E. A.; Chekanova, L. A.; Iskhakov, R. S.; Bondarenko, G. N.

    2013-05-01

    The electroless plating is used to synthesize two types of composite powder, such as the activated carbon with pores filled by Co100-XPX particles and the Al2O3 microgranular coated by the shell which consists of Co100-XPX particles with 4 powders decreases from 300 nm to 120 nm with an increase in P- content from 4 to 18 at. %. It causes a reduction in coercivity from 300 to 80 Oe for Al2O3/Co(P) powders and from 680 to 150 Oe for C/Co(P) powders. The effects of two methods of immobilization of Co(P) particles on magnetic properties are studied.

  14. Thermodynamics and kinetics of electroless Ni-P plating on Fe powder%Fe粉表面化学镀Ni-P的热力学与动力学

    Institute of Scientific and Technical Information of China (English)

    闫操; 戴玉林; 徐宏; 侯峰; 姚志燕

    2011-01-01

    为了改善粉末的表面性状、提高其耐腐蚀及耐磨损性能、降低烧结温度,文中用化学镀法在Fe粉表面包覆了低熔点的Ni-P合金镀层.为了更好地控制粉体化学镀的沉积速率及探讨其沉积机制,引入电化学Bockris方程式、用称量法测定Fe粉表面镀层的沉积量,根据热力学基本方程式求得了热力学函数ΔG㈠dep,ΔS㈠dep,ΔH㈠dep,并研究了各个实验因素对应的动力学参数,建立了沉积速率的经验方程式.实验结果表明:粉体化学镀的最佳施镀温度为362 K,高于此温度时,镀液易分解.在施镀温度范围内,化学反应过程可自发进行,体系为吸热反应.%In order to improve the properties of Fe powder such as inoxidability and abrasion resistance, and drop the sintering temperature, the electroless Ni-P plating on Fe powder was prepared successfully. Bockris equation of the electrochemistry was applied to the thermodynamics of Fe powder electroless Ni-P plating for controlling its deposit rate and deposit mechanism. The thermodynamics functions △Gdep(o), △Sdep(o) and △Hdep(o) were figured out by studying the deposit amount of coating. In addition, the experiential equation of electroless deposition was established. The results show that the optimal temperature of electroless plating is 362 K. If it is higher than such temperature, the plating liquor may easily decompose. Within the range of optimal temperature, the chemical reaction can occur spontaneously. The reaction of this system is endothermic.

  15. Supercritical CO2 assisted electroless plating on polypropylene substrate-effect of injection speed on adhesive force of metal to polymer

    Science.gov (United States)

    Ohshima, Masahiro; Tsubouchi, Kensuke; Ishihara, Shota; Hikima, Yuta; Tengsuwan, Siwach

    2016-03-01

    The aqueous plating solution cannot be diffused into a plain polypropylene (PP) substrate and consequently Ni-P metal layer cannot be formed by electroless plating on the PP substrate with a satisfied degree of adhesive force unless the hydrophilicity of the substrate surface was increased. A block copolymer PP-b-polyethylene oxide (PP-b-PEO) was used to increase the hydrophilicity of the surface and the adhesive force of the metal layer to the satisfactory level. Our previous study showed the morphology of PP-b-PEO domain near the surface of substrate strongly affected the adhesiveness of the metal layer to the substrate. The degrees of elongation and orientation of the PP-b-PEO domains in PP matrix were the key factors of determining the thickness of the metal-PP composite layer and the resulting adhesive strength. In this study, the effect of injection molding condition on the degrees of elongation and orientation was investigated: PP/PP-b-PEO blend substrates were prepared by injection molding at different injection speed. The higher injection speed increased the degrees of elongation and orientation of copolymer and formed multilayered structure of the copolymer domains. It could produce the electroless plating PP substrate with the higher adhesive strength of the Ni-P metal layer to the PP substrate.

  16. Electroless plating of Ni-Zn(Fe)-P alloy on carbon steel sheets

    Institute of Scientific and Technical Information of China (English)

    WANG Sen-lin; WU Hui-huang

    2004-01-01

    The autocatalytic deposition of Ni-Zn(Fe)-P alloys were carried out on carbon steel sheets from bath containing nickel sulfate, zinc sulfate, sodium hypophosphite, sodium citrate and boric acid. The effects of pH and mole ratio of NiSO4/ZnSO4 on the deposition rate and the composition of deposit were studied. It is found that the presence of zinc sulfate in the bath has an inhibitory effect on the alloy deposition. As a consequence, the mole fraction of zinc in the deposits never reaches high value, which is less than 18.0%. The structure and surface morphology of Ni-Zn(Fe)-P coatings were charactered by XRD and SEM. The alloys plated at all conditions consist of amorphous phase coexisting with a crystalline cubic Ni phase. The surface morphology of coating is dependent on the deposition parameters.

  17. Surface-enhanced Raman scattering of patterned copper nanostructure electrolessly plated on arrayed nanoporous silicon pillars

    Energy Technology Data Exchange (ETDEWEB)

    Jiang Weifen; Shan Wenwen; Ling Hong; Wang Yusheng [Department of Mathematics and Information Science, North China Institute of Water Conservancy and Hydroelectric Power, Zhengzhou 450011 (China); Cao Yanxia [College of Materials Engineering, Zhengzhou University, Zhengzhou 450052, People' s Republic of China (China); Li Xinjian, E-mail: gingerwfj@yahoo.com.c [Department of Physics and Laboratory of Material Physics, Zhengzhou University, Zhengzhou 450052 (China)

    2010-10-20

    A new synthesized composite structure, a patterned copper/silicon nanoporous pillar array (Cu/Si-NPA) made by depositing Cu on Si-NPA using an immersion plating method, can be used as a surface-enhanced Raman scattering (SERS) substrate. Its surface component and morphology were analyzed by x-ray diffraction and field-emission scanning electron microscopy, respectively. It was found that the surface was Cu with two kinds of crystal structures: a continuous film composed of Cu nanocrystallites covering the Si-NPA, and a quasi-regular, interconnected network composed of loop-chains of Cu crystallites, with the size in the range of several tens of nanometer to 300 nm, surrounding the porous Si pillars. The composite structure is strongly SERS active using rhodamine 6G as probe molecules, which is mainly due to the patterned hierarchical Cu structure.

  18. Study on Electroless Plating Ni-Ce-P Process on 27SiMn Surface%27SiMn化学镀Ni-Ce-P工艺研究

    Institute of Scientific and Technical Information of China (English)

    任鑫; 杜学芸; 侯静; 谷永旭

    2011-01-01

    Based on the mining hydraulic support column 27SiMn, the cerous sulfate was added to the electroless Ni-P solution. The plating velocity was used as an evaluation indice, the optimum technology was obtained by orthogonal test. At the same time, the morphology of the plating obtained at the optimum technology was analyzed. The results show that the plating velocity reaches 33.38 μm/h under the condition of the solution containing 40 mg/L cerous sulfate. Compared with the electroless plating Ni-P coating, Ni-Ce-P plating surface becomes more compact and smooth.%以液压支架立柱常用材料27SiMn为基体,在Ni-P化学镀的基础上加入稀土硫酸高铈.通过正交试验对施镀工艺参数进行优化,以镀速为评定指标,获得了化学镀Ni-Ce-P的最优工艺配方,并对最优工艺条件下得到镀层的形貌进行了分析.结果表明:含有40 mg/L硫酸高铈的最优配方下的镀速为33.38 μm/h;相对于二元Ni-P镀层,加入稀土得到的镀层胞状结构更细小,表面更加平整、致密.

  19. Electromagnetic properties of core–shell particles by way of electroless Ni–Fe–P alloy plating on flake-shaped diatomite

    International Nuclear Information System (INIS)

    Flake-shaped diatomite particles coated by Ni–Fe–P alloy were prepared by electroless plating technique and processed by heat treatment. The samples were characterized by SEM, EDS and XRD. The results indicated that the magnetic diatomite particles had continuous and homogeneous Ni–Fe–P coating, and the phase constitution of the Ni–Fe–P coating was transformed from an amorphous structure to a crystalline structure during heat treatment. The measured electromagnetic parameters and the calculated reflection loss suggested that heat treatment was able to enhance the microwave absorption performance of the paraffin wax based composites. In a word, the Ni–Fe–P coated diatomite particle obtained in this paper is a promising candidate for lightweight microwave absorbing inclusions. - Highlights: • We used the flake-shaped diatomite particles as forming template to fabricate the core–shell ferromagnetic particles. • The diatomite particles were deposited Ni–Fe–P alloy by way of electroless plating methods. • The coated diatomite particles were lightweight ferromagnetic fillers. • The composites containing coated diatomite particles with heat treatment exhibited great potential in the field of electromagnetic absorbing

  20. Ultrasonic preparation of nano-nickel/activated carbon composite using spent electroless nickel plating bath and application in degradation of 2,6-dichlorophenol.

    Science.gov (United States)

    Su, Jingyu; Jin, Guanping; Li, Changyong; Zhu, Xiaohui; Dou, Yan; Li, Yong; Wang, Xin; Wang, Kunwei; Gu, Qianqian

    2014-11-01

    Ni was effectively recovered from spent electroless nickel (EN) plating baths by forming a nano-nickel coated activated carbon composite. With the aid of ultrasonication, melamine-formaldehyde-tetraoxalyl-ethylenediamine chelating resins were grafted on activated carbon (MFT/AC). PdCl2 sol was adsorbed on MFT/AC, which was then immersed in spent electroless nickel plating bath; then nano-nickel could be reduced by ascorbic acid to form a nano-nickel coating on the activated carbon composite (Ni/AC) in situ. The materials present were carefully examined by Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, X-ray photoelectron spectroscopy and electrochemistry techniques. The resins were well distributed on the inside and outside surfaces of activated carbon with a size of 120 ± 30 nm in MFT/AC, and a great deal of nano-nickel particles were evenly deposited with a size of 3.8 ± 1.1 nm in Ni/MFT. Moreover, Ni/AC was successfully used as a catalyst for ultrasonic degradation of 2,6-dichlorophenol.

  1. Ultrasonic preparation of nano-nickel/activated carbon composite using spent electroless nickel plating bath and application in degradation of 2,6-dichlorophenol.

    Science.gov (United States)

    Su, Jingyu; Jin, Guanping; Li, Changyong; Zhu, Xiaohui; Dou, Yan; Li, Yong; Wang, Xin; Wang, Kunwei; Gu, Qianqian

    2014-11-01

    Ni was effectively recovered from spent electroless nickel (EN) plating baths by forming a nano-nickel coated activated carbon composite. With the aid of ultrasonication, melamine-formaldehyde-tetraoxalyl-ethylenediamine chelating resins were grafted on activated carbon (MFT/AC). PdCl2 sol was adsorbed on MFT/AC, which was then immersed in spent electroless nickel plating bath; then nano-nickel could be reduced by ascorbic acid to form a nano-nickel coating on the activated carbon composite (Ni/AC) in situ. The materials present were carefully examined by Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, X-ray photoelectron spectroscopy and electrochemistry techniques. The resins were well distributed on the inside and outside surfaces of activated carbon with a size of 120 ± 30 nm in MFT/AC, and a great deal of nano-nickel particles were evenly deposited with a size of 3.8 ± 1.1 nm in Ni/MFT. Moreover, Ni/AC was successfully used as a catalyst for ultrasonic degradation of 2,6-dichlorophenol. PMID:25458692

  2. Structure and 57Fe conversion electron M(o)ssbauer spectroscopy study of Mn-Zn ferrite nanocrystal thin films by electroless plating in aqueous solution

    Institute of Scientific and Technical Information of China (English)

    SUN JianRong; WANG XueWen; LIU JinHong; WANG JianBo; LI FaShen

    2008-01-01

    Mn1-xZnxFe2O4 thin films with various Zn contents and of different thickness were synthesized on glass substrates directly by electroless plating in aqueous solution at 90℃ without heat treatment. The Mn-Zn ferrite films have a single spinel phase structure and well-crystallized columnar grains growing per-pendicularly to the substrates. The results of conversion electron 57Fe Mossbauer spectroscopy (CEMS) indicate that the cation distribution of Mn-xZnxFe2O4 ferrite nanocrystal thin films fabricated by elec-troless plating is different from the bulk materials' and a great quantity of Fe3+ ions are still present on A sites for x>0.5. When the Zn content of the films increases, Fe3+ ions in the films transfer from A sites to B sites and the hyperfine magnetic field reduces, suggesting that Zn2+ has strong chemical affinity towards the A sites. On the other side, with the increase of the thickness of the films, Fe3+ ions, at B sites in the spinel structure, increase and the array of magnetic moments no longer lies in the thin film plane completely. At x=0.5, Hc and Ms of Mn1-xZnxFe2O4 thin films show a minimum of 3.7 kA/m and a maximum of 419.6 kA/m, respectively.

  3. Electromagnetic properties of core–shell particles by way of electroless Ni–Fe–P alloy plating on flake-shaped diatomite

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Deyuan [Bionic and Micro/Nano/Bio Manufacturing Technology Research Center, School of Mechanical Engineering and Automation, Beihang University, Beijing 100191 (China); Yuan, Liming, E-mail: lming_y@163.com [Bionic and Micro/Nano/Bio Manufacturing Technology Research Center, School of Mechanical Engineering and Automation, Beihang University, Beijing 100191 (China); Lan, Mingming; Hu, Yanyan; Cai, Jun [Bionic and Micro/Nano/Bio Manufacturing Technology Research Center, School of Mechanical Engineering and Automation, Beihang University, Beijing 100191 (China); Zhang, Wenqiang [College of Engineering, China Agricultural University, Beijing 100083 (China); Li, Haiyang [China Aerospace Science and Technology Corporation, Beijing 100854 (China)

    2013-11-15

    Flake-shaped diatomite particles coated by Ni–Fe–P alloy were prepared by electroless plating technique and processed by heat treatment. The samples were characterized by SEM, EDS and XRD. The results indicated that the magnetic diatomite particles had continuous and homogeneous Ni–Fe–P coating, and the phase constitution of the Ni–Fe–P coating was transformed from an amorphous structure to a crystalline structure during heat treatment. The measured electromagnetic parameters and the calculated reflection loss suggested that heat treatment was able to enhance the microwave absorption performance of the paraffin wax based composites. In a word, the Ni–Fe–P coated diatomite particle obtained in this paper is a promising candidate for lightweight microwave absorbing inclusions. - Highlights: • We used the flake-shaped diatomite particles as forming template to fabricate the core–shell ferromagnetic particles. • The diatomite particles were deposited Ni–Fe–P alloy by way of electroless plating methods. • The coated diatomite particles were lightweight ferromagnetic fillers. • The composites containing coated diatomite particles with heat treatment exhibited great potential in the field of electromagnetic absorbing.

  4. Study of silver activating solution used in PCB electroless copper plating%银活化液在PCB化学镀铜的研究

    Institute of Scientific and Technical Information of China (English)

    杨琼; 陈世荣; 汪浩; 曹权根; 王恒义; 谢金平; 范小玲

    2013-01-01

    文章简述了印制电路板孔金属化用的各种钯活化液的原理和特点,提出了一种银活化液,并将其催化活性和催化效果与胶体钯进行了对比。结果表明银活化用于化学镀铜,诱导时间快,可以节约成本。%This paper describes the principles and characteristics of various PCB plated through hole palladium activating solution, we propose a silver activation solution and its catalytic activity and catalytic effects were compared with colloidal palladium. The results show that silver activation solution can quickly induce electroless copper plating, and save production cost.

  5. Potentiodynamic studies of Ni-P-TiO2 nano-composited coating on the mild steel deposited by electroless plating method

    Science.gov (United States)

    Uttam, Vibha; Duchaniya, R. K.

    2016-05-01

    Now a days, corrosion studies are important for reducing the wastage of metals. The importance of corrosion studies is two folds i.e. first is economic, including the reduction of material losses resulting from the wasting away or sudden failure of materials and second is conservation Electroless process is an autocatalytic reduction method in which metallic ions are reduced in the solution. Nanocomposite coatings of Ni-P-TiO2 on mild steel are deposited by varying volume of TiO2 nano-powder by electroless method from Ni-P plating bath containing Nickel Sulphate as a source of nickel ions, sodium hypophosphite as the reducing agent, lactic acid as a complexing agents and TiO2 nano powder. Electroless Ni-P-TiO2 coating have been widely used in the chemical process industries, mechanical industries, electronic industries and chloroalkali industries due to their excellent corrosion with mechanical properties. In the present work, deposition of Ni-P alloy coating and Ni-P-TiO2 nanocomposited coatings were done on the mild steel and corrosion properties were studied with Potentio-dynamic polarization measurements method in 3.5 wt% sodium chloride solution. It showed in the experiments that Ni-P-TiO2 nanocomposited coating has better corrosion resistance as comparedthan Ni-P alloy coating. Morphological studies were done by field emission scanning electron microscopy (FESEM), energy-dispersive analysis of X-ray (EDAX) and X-ray diffraction (XRD). These studies confirmed the deposition of Ni-P alloy coating and Ni-P-TiO2 nanocomposited coating.

  6. 镍-铜复合镀层Kevlar纤维的研制%Development and Research of Electroless Ni-Cu Plated Kevlar Fibers

    Institute of Scientific and Technical Information of China (English)

    梁晶晶; 邹新国; 张慧茹; 邵勤思; 唐志勇; 孙晋良

    2012-01-01

    采用化学镀技术制备了镍-铜复合镀层的导电Kevlar纤维。进行了自制金属化试剂对Kevlar纤维的粗化处理,研究了镍镀层含量、添加剂聚乙二醇(PEG6000)和亚铁氰化钾(K4Fe(CN)6))对化学镀铜的影响。实验表明,镍镀层质量增加率为10%较适宜继续化学镀铜;添加剂均可降低化学镀铜的沉积速度,PEG6000能够细化圆滑镀层颗粒,K4Fe(CN)6使得镀层表面平整光亮,制得光滑致密有金属光泽的铜镀层,并提高其导电性。镍-铜复合镀层Kevlar纤维的断裂强力为45 N,表面电阻为0.4Ω/cm。%Electroless copper plating at the nickel modified surface of Kevlar fibers was investigated. The surface of Kevlar fibers was roughened using sodium hydride-dimethyl sulfoxide (NaH-DMSO). Then, influence of Ni weight gain rate and additives (polyethylene glycol PEG6000 and potassium ferrocyanide K4Fe(CN)6) on electroless Cu plating was studied. The results show that favorable Ni weight gain rate is approximate 10 %, PEG6000 and K4Fe (CN)6 increase the stability of plating bath, and reduce the deposition rate of electroless Cu plating. Copper grains turn fine, sleek and homogeneous with adding PEG6000. Copper deposits become more compact, smoother and brighter with adding KaFe (CN)6. Correspondingly, the appearance of deposits changes from dark-brown to red brown, and then to bright copper. Meanwhile, the conductivity of deposits increases. The properties tests show that breaking strength of Ni-Cu coated Kevlar fibers is 45N and thesiarface resistance is 0.4Ω/cm.

  7. CFD simulation of hydrogen mixing and mitigation by means of passive auto-catalytic recombiners

    Energy Technology Data Exchange (ETDEWEB)

    Kelm, S.; Reinecke, E-A.; Jahn, W., E-mail: s.kelm@fz-juelich.de [Forschungszentrum Juelich GmbH, Juelich (Germany); Allelein, H-J. [RWTH Aachen Univ.. Aachen (Germany)

    2011-07-01

    Modeling of passive auto-catalytic recombiners (PARs) operation in containment geometries involves a large variety of scales; thus, a CFD calculation resolving all these scales would be much too expensive. Therefore, the mechanistic PAR model REKO-DIREKT, developed at Forschungszentrum Juelich, has been coupled with the commercial CFD code ANSYS CFX in order to simulate PAR operation as well as the induced flow and transport phenomena. Based on a short introduction of REKO-DIREKT, its interface to CFX and the explicit coupling scheme is discussed. The paper is finalized by a first demonstration of simulation capabilities on the basis of the ThAI PAR-4 experiment (Becker Technologies GmbH, Eschborn, Germany). (author)

  8. Electroless Ni alloy plating as a diffusion barrier for through silicon vias in three-dimensional packaging

    Science.gov (United States)

    Kim, Taeyoo; Ahn, Byungwook; Lim, SeungKyu; Son, Hwajin; Suh, Sujeong

    2016-02-01

    Ni- and Co-based amorphous films are alternative diffusion barrier materials for Cu interconnection in three-dimensional (3D) packaging applications. In this paper, electroless Ni-P and Ni-W-P films deposited in through-silicon vias (TSVs) were prepared as a diffusion barrier and seed layer of Cu filling by using Sn-Pd activation pretreatment. The thermal stability of the electroless Ni alloy films subjected to rapid thermal annealing (RTA) in H2 atmosphere was investigated. The barrier properties of the electroless Ni alloy films were evaluated over a range of temperatures using auger electron spectroscopy (AES) and energy dispersive X-ray spectroscopy (EDS) line-scan. The microstructures, crystal structures and electrical resistivity were also examined. It was found that Ni alloy films are amorphous as deposited, that the films retain amorphous or amorphous-like structures after undergoing annealing at 400 °C for 1 h, and that they are feasible for the diffusion barrier layer for 3D Cu interconnect technology.

  9. Development of nickel membranes deposited on ceramic materials by electroless plating: studies of the hydrogen perm-selectivity properties at elevated temperatures

    International Nuclear Information System (INIS)

    The main objective of this work was to synthesize nickel based membranes by electroless plating on materials such as alumina-α, alumina-γ and zirconia with various textures and to determine their hydrogen perm-selectivity at high temperatures. The synthesis of metal films of high purity (≥ 99% mass Ni) resulting from the choice of hydrazine with its dual role of reducing and complexing agent has revealed that the diameter of pores on the surface support has an impact on the quality of metal adherence. The various contributions of hydrogen transport through these composite membranes at low temperatures (Knudsen and surface diffusion) and at high temperatures (Knudsen and activated diffusion) was established. At its implementation in a membrane reactor (reaction of propane dehydrogenation), the layer of nickel showed a very good resistance to coking. (author)

  10. Preparation and thermal treatment of Pd/Ag composite membrane on a porous α-alumina tube by sequential electroless plating technique for H2 separation

    Institute of Scientific and Technical Information of China (English)

    E.Navaei Alvar; M.Reza Golmohammadi; M.Rezaei; H.Navaei Alvar; A.Mardanloo; S.Habibzad Nouhian; M.Didari

    2008-01-01

    Pd/Ag/α-Al2O3 composite membranes were prepared by sequential electroless plating technique. The prepared membranes were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spec-troscopy, and inductively coupled plasma atomic emission spectroscopy techniques (ICP-AES). Effects of annealing time, Ag content, and air treatment on the hydrogen permeation flux and morphology of the alloys were investigated. The results of the investigation showed that the prepared type of tube had a good potential as substrate for membrane preparation. In addition, a uniform defect-free alloy was prepared by annealing at 550 ℃ in H2 atmosphere. The permeation results showed an increase in H2 permeation flux by increasing the Ag content and the annealing time. In addition, the air treatment of the prepared membranes at 400 ℃ for 1 h changed the morphology of the alloy and substantially enhanced the hydrogen flux.

  11. 纯铜化学镀Ni-Cu-P工艺的研究%A Study of Electroless Ni-Cu-P Plating on Pure Copper

    Institute of Scientific and Technical Information of China (English)

    陈益兵; 赵芳霞; 张振忠; 孙晓东

    2013-01-01

    Aiming at the problems of corrosion and boundary conductivity to be improved when pure copper is in the process of application, the surface of pure copper was modified by electroless Ni-Cu-P plating. The effects of electroless Ni-Cu-P plating process on the properties of pure copper were investigated by means of XRD, SEM, contact resistance test, corrosion test, etc.The results show that the process can obtain a typical amorphous cellular structure, the contact resistance of modified pure copper is 15 % ~ 30 % of that before modification, and the self-corrosion current density is decreased by two orders of magnitude.%针对纯铜使用过程中表面腐蚀及导电性需进一步提高等问题,采用化学镀Ni-Cu-P对纯铜进行表面改性.采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、界面接触电阻测试、极化曲线等手段,研究了化学镀Ni-Cu-P工艺对纯铜性能的影响.结果表明:该工艺能得到典型的非晶胞状结构,改性后纯铜的接触电阻为改性前的15 %~30%,自腐蚀电流密度降低两个数量级.

  12. Electroless plating of low-resistivity Cu–Mn alloy thin films with self-forming capacity and enhanced thermal stability

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Sung-Te, E-mail: stchen@mail.hust.edu.tw [Department of Electronic Engineering, Hsiuping University of Science and Technology, Dali 412, Taichung, Taiwan (China); Chen, Giin-Shan [Department of Materials Science and Engineering, Feng Chia University, Seatwen 407, Taichung, Taiwan (China)

    2015-11-05

    Previous studies have typically used sputter deposition to fabricate Cu–Mn alloy thin films with concentrated solute additions which have exceeded several atomic percentages, and the electrical resistivity values of the resultant films from previous studies are relatively high, ranging from 2.5 to 3.5 μΩ-cm. Herein, we proposed a different approach by using electroless process to plate dilute Cu–Mn (0.1 at.%) alloy thin films on dielectric layers (SiO{sub 2}). Upon forming-gas annealing, the Mn incorporated into Cu–Mn films was segregated toward the SiO{sub 2} side, eventually converting itself into a few atomic layer thickness at the Cu/SiO{sub 2} interface, and forming films with a low level of resistivity the same as that of pure Cu films (2.0 μΩ-cm). The interfacial layer served as not only a diffusion barrier, but also an adhesion promoter that prevented the film’s agglomeration during annealing at elevated temperatures. The mechanism for the dual-function performance by the Mn addition was elucidated by interfacial bonding analysis, as well as dynamic (adhesive strength) and thermodynamic (surface-tension) measurements. - Highlights: • Electroless plating is proposed to grow dilute (0.1%) Cu–Mn films on SiO{sub 2} layers. • Adequate annealing results in a self-forming of MnO{sub x} at the Cu/SiO{sub 2} interface. • The role of interfacial MnO{sub x} as a barrier and adhesion promoter is demonstrated. • The treated dilute film has a low ρ level of pure Cu, in contrast to concentrated films. • Its potential as a single entity replacement of Cu interconnect is presented.

  13. Phytic acid activation prior to electroless nickel plating on magnesium alloy%镁合金化学镀镍前植酸活化工艺

    Institute of Scientific and Technical Information of China (English)

    王娟; 丁毅; 尹明勇; 马立群

    2012-01-01

    通过植酸活化可提高AZ31镁合金化学镀层的耐蚀性能.采用正交试验优化植酸活化工艺,利用金相显微镜观察了植酸膜的微观形貌,测定了植酸膜在质量分数为3.5%的NaCl溶液中的极化曲线及在化学镀镍液中的开路电位.结果表明,当植酸质量浓度为20 g/L、温度为50 ℃、pH=8时处理25 min,植酸膜具有良好的耐蚀性能,并且能够作为化学镀的活化层.%The corrosion resistance of AZ31 magnesium alloy can be improved by phytic acid activation. The phytic acid activation process was optimized through orthogonal test. The micro-morphology of phytic acid coating was observed by metallographic microscope, and its polarization curve in 3.5wt% NaCl solution and open circuit potential in electroless nickel plating bath were measured. The results showed that the phytic acid coating obtained with phytic acid 20 g/L at 50 ℃ and pH 8 for 25 min has good corrosion resistance and can be used as an activated layer for electroless nickel plating.

  14. Modeling of Auto-Catalytic Halogen Release and Ozone Depletion in Polar Regions

    International Nuclear Information System (INIS)

    This article concerns the modeling of the tropospheric ozone depletion event in polar spring where the aim is an improved understanding of the underlying physical and chemical processes. For this purpose, a model based on OpenFOAM 1.7.1 is developed, where two-dimensional compressible Navier-Stokes equations are solved numerically by finite volume method to predict the effects of turbulent mixing, advection of the fluid, and detailed chemical reactions. The present chemical reaction mechanism consists of 53 chemical reactions among 33 species to model the auto-catalytic process considering halogen species X, X2, XY, XO, HOX, where X and Y denote halogen atoms - here Br is studied. Large eddy simulation is applied to account for the turbulence and the Smagorinsky model is employed as sub-grid model. Good agreement with literature and experimental data is obtained for the profiles of the chemical species. In particular, the correct time scale of the phenomenon is captured. It is confirmed that the mixing ratio of ozone in the troposphere drops to a value near zero within several days. Moreover, it is shown that the well-mixed air is confined inside the boundary layer. A parameter study shows that the ozone depletion event happens even at reduced initial values of molecular bromine. Also, the study of coupled transport and chemistry shows that the turbulent mixing enhances the ozone depletion in the lowest layer above the earth's surface.

  15. 桐木板材表面化学镀镍工艺的研究%Electroless Nickel Plating on Surface of Paulownia Wood

    Institute of Scientific and Technical Information of China (English)

    刘西德

    2015-01-01

    The operating methods, the process and the influence of several factors on nickel-plating on the surface of ordinary paulownia wood were studied. Then the combination strength between chemical coating and paulownia wood was tested, the process and the optimum conditions were determined finally. The quality of electroless nickel-plating was good when the paulownia wood were pretreated, sensitized and activated, the pH=8.0, the reaction temperature was 65℃and the reaction time was 40 min.%实验研究了桐木板材表面化学镀镍的操作方法和工艺条件,讨论了各种操作因素对镀层质量的影响,试验了化学镀层与镀件基体的结合力,确定了桐木板材化学镀镍的工艺流程和控制条件。实验结果表明,桐木板材经过预处理及敏化、活化处理后,化学镀镍溶液的pH值控制在8.0,镀镍温度控制在65℃,反应时间40min,桐木板材表面可以得到较好的金属镀层。

  16. Effects of Mm(NiCoAlMn)5 hydrogen storage alloy coated with Ni-Co-P alloy by electroless plating on electrochemical properties of hydride electrodes

    Institute of Scientific and Technical Information of China (English)

    孙春文; 郭占成; 唐致远; 郭鹤桐

    2003-01-01

    The effect of chemical plating with Ni-Co-P alloy on the properties of MH electrodes is investigated. The results show that the efficiency of storage alloy and the activation of MH electrode have been improved by introducing 1.74% cobalt in the Ni-Co-P alloy coating. The initial discharge capacity is 208 mAh/g. The maximum discharge capacity gets to 298.5 mAh/g. At the same time the cycle life of MH electrodes is improved. The discharge capacity of MH electrodes coated with Ni-Co-P is 88% of the maximum discharge capacity after 300 cycles. Whereas the discharge capacity of bare alloy electrodes retains 62% of the maximum capacity after 300 cycles. An increment of discharge capacity is mainly due to the superposition of the oxidation current of Co as well as improved efficiency of microcurrent collection. The effect of Ni-Co-P alloy coating by electroless plating on the kinetic properties of hydride electrode has been systematically investigated by electrochemical techniques. The results indicate that the kinetic properties of MH electrodes, including exchange current density, limiting current density, have been improved markedly. This improvement of kinetic properties leads to the decrease of the overpotential of anodic and cathodic polarization.

  17. Ni-P化学镀层表面黏液形成菌微生物污垢特性%Microbial fouling characteristics of slime-forming bacteria on the surface of electroless plating of Ni-P

    Institute of Scientific and Technical Information of China (English)

    武霖; 姚响

    2015-01-01

    A new experiment was designed to investigate microbial fouling characteristics on heat exchanger of electroless plating of Ni-P. In this paper,the surface of low-carbon steel sheet,which is common for heat exchanger,was modified by using the method of electroless Ni-P and low-carbon steels before and after electroless Ni-P,and pictures were taken by scanning electron microscopy. A comparative experiment was designed to investigate microbial fouling characteristics of low-carbon steel sheet and low-carbon steel sheet with electroless plating of Ni-P. Slime-forming bacteria that was isolated and purified from Songhua River is chosen as the strains. The changes of fouling were recorded by the method of weighing,and the changes of bacterial counts were recorded by the method of optical turbidity. The results of the experimental show that the surface morphology of electroless plating of Ni-P is better than that of low-carbon steel after the low-carbon steel sheet was electroless plated. For the corrosion caused by slime-forming bacteria,the corrosion resistance of electroless plating of Ni-P is better than that of low-carbon steel sheet and the anti-microbial fouling of electroless plating of Ni-P is preferred. When the slime-forming bacteria grew and reproduced vigorously and metabolites were excessive,biofouling was formed soon; in contrast,biofouling was formed slowly.%为了研究化学镀Ni-P换热器上黏液形成菌微生物污垢的特性,利用化学镀Ni-P的方式对低碳钢表面进行改性。采用微生物污垢对比实验,对低碳钢片和具有Ni-P镀层低碳钢片拍摄扫描电镜图,利用称重法记录污垢变化情况和光电比浊法记录黏液形成菌的数量变化情况。结果表明,Ni-P 镀层表面形貌明显好于低碳钢;Ni-P镀层相比于碳钢具有很好的耐蚀性和抗微生物污垢特性;黏液形成菌生长繁殖旺盛和细菌代谢产物多时,微生物污垢的形成就快。相反,微生物污垢形成就慢。

  18. Study on the technology of Alkaline Electroless Plating Ni-Cu-P%碱性化学镀Ni-Cu-P工艺研究

    Institute of Scientific and Technical Information of China (English)

    崔绍波

    2016-01-01

    通过正交试验,以硫酸镍和硫酸铜为主盐、次磷酸钠为还原剂研究了铝片表面的化学镀Ni-Cu-P工艺,其最优工艺配方为:硫酸镍25 g/L,硫酸铜2.0 g/L,次亚磷酸钠24 g/L,柠檬酸钠45 g/L,硫脲2.5mg/L,NaF 0.15 g/L,OP-100.8 mg/L,pH值9,温度70℃,施镀时间40min。通过耐硝酸变色试验检测了沉积层的抗蚀性,并讨论了沉积层抗蚀性的影响因素。%Taking nickel sulfat copper sulfat as main salt ,hypophosphite as the reduced agent , and by means of orthogonal experiment , the paper dtudies the technology of electroless plating Ni -Cu-P on the surface of aluminium plate .The optimal process formula is i-dentified as below:NiSO4 · 6H2 O 25g/L, CuSO4 · 5H2 O 2.0g/L,NaH2 PO2 · H2 O 24g/L, sodium citrate 45g/L, CN2 H4 S 2.5mg/L, NaF 0.15g/L, OP-10 0.8mg/L, ph value 9, temperature 70, and plating time 40min.The corrosion resistance pf deposited layer is checked by means of nitric acid resisting , and many effects on the deposits are investigated .

  19. Effect of Heat Treatment on Structure and Magnetic Performance of Ni-Fe-P Alloy Obtained by Electroless Plating

    Institute of Scientific and Technical Information of China (English)

    WANG Sen-lin; ZHANG Yong

    2005-01-01

    The electroless deposition of Ni68-Fe10.5-P21.5 alloy has been investigated. The crystallization behavior of the deposit was comparatively studied by using differential scanning calorimetry and X-ray diffractometry. The deposit transforms into a square Ni3P phase at 380.0 ℃, then changes into a cubic FeNi3 phase at 490.0 ℃. The microhardness,the size of the formed grains and the magnetic performance of the deposit increase with the increase of the heat treatment temperature below 500 ℃, then they decrease after this temperature. The effect of heat treatment time at 500 ℃on the surface micromorphology, the structure and the magnetic performance of the deposit were also studied. The resuIts show that with the increase of heat treatment time, the extent of crystallization of the deposit increases and the size of the formed grains becomes uniform. The results also show that the magnetic performance of the deposit under heat treatment for 40 min is maximal and then decreases with the increase of heat treatment time. The property change of the deposit is related to the crystal structure and the size of the formed grains of the deposit.

  20. Ultrasonic enhanced electroless copper plating on microporous polyurethane foam%微孔聚氨酯泡沫超声强化化学镀铜的研究

    Institute of Scientific and Technical Information of China (English)

    田庆华; 郭学益

    2011-01-01

    为研制金属泡沫材料电沉积制备所需的导电泡沫基体,以孔径为0.3mm的微孔聚氨酯泡沫为基体进行化学镀铜新工艺研究.探讨镀液组成、温度、pH及超声强化对化学镀铜工艺的影响,得出化学镀铜优化工艺条件如下:硫酸铜质量浓度为16g/L,酒石酸钾钠质量浓度为30 g/L,Na2EDTA质量浓度为20g/L,α,α'-联吡啶质量浓度为25 mg/L,亚铁氰化钾质量浓度为25 mg/L,PEG-1000质量浓度为1g/L,甲醛含量为5mL/L,镀液pH为12.5~13.0,温度为50℃.在此条件下,镀液稳定性好,镀层光亮平整,镀速可达0.102 mg/min;超声强化可有效提高镀速20%~30%;化学镀铜后的导电泡沫基体经电沉积工艺可制备得到孔隙率为92.2%的三维网状金属泡沫材料.%In order to get good conductive foam substrates for foam metal materials, a novel method for electroless copper plating on microporous polyurethane foam with diameter of 0.3 mm was proposed. The main factors affecting the plating rate such as the solution composition, temperature, pH and adding ultrasonic were investigated comprehensively.The results show that the optimal conditions are 16 g/L CuSO4, 5 mL/L HCHO, 30 g/L NaKC4H4O6, 20 g/L Na2EDTA,25 mg/L α,α′-Dipyridyl, 25 mg/L K4Fe(CN)6, 1 g/L PEG-1000, at pH 12.5-13.0, temperature 50 ℃. Under above conditions, the process has efficient bath stability with the plating rate up to 0.102 mg/min. The result shows that adding ultrasonic on the process can elevate the plating rate of copper by 20%-30%. Foam metal material with a porosity of 92.2%, and a three-dimensional network structure can be fabricated by electrodeposition after electroless copper plating.

  1. Electroless Silver Plating on Hollow Glass Microsphere Modified by Silane Coupling Agent%空心玻璃微珠偶联化学镀银的研究

    Institute of Scientific and Technical Information of China (English)

    朱国庆; 文力; 张辉

    2012-01-01

    Surface of hollow glass microsphere was firstly modified by silane coupling agent, and then applying electroless silver plating directly. Surface morphology and structure of the coating were characterized by FTIR, SEM and XRD techniques. Results showed that compared with the colloidal palladium activation and silver ammonium solution activation methods, this silane coupling method could result in a uniform and compact coating with superior conductivity, higher adhesion and better silver utilization.%使用氨丙基三乙氧基硅烷偶联剂改性空心玻璃微珠表面,然后直接实施化学镀银,借助红外光谱、扫描电镜和X-射线衍射测试手段对偶联改性效果、镀层表面形貌和结构进行了表征.测试结果表明,与胶体钯活化法和硝酸银活化法化学镀银相比,空心玻璃微珠偶联表面改性直接化学镀银的镀层更为致密、均匀,银利用率高,导电性好,结合力强.

  2. Complete filling of 41 nm trench pattern using Cu seed layer deposited by SAM-modified electroless plating and electron-beam evaporation

    International Nuclear Information System (INIS)

    To overcome the limitation of the sputtered Cu seed layer in electroplating of Cu interconnects imposed by the shadow effect, a new method for depositing a Cu seed layer on a 41 nm trench pattern based on combination of electroless plating (ELP) and electron-beam (E-Beam) evaporation was developed. A Cu seed layer formed by ELP alone was too thin to be used for electroplating due to its high resistivity. To solve this problem, an additional Cu layer was deposited on top of the trench by E-Beam evaporator to enhance the electrical conductivity of the Cu seed layer. The electrical resistivity of the resulting Cu layer was reduced to 4.8 μΩ cm, which was sufficient for the conductive seed layer for electroplating the 41 nm trench pattern. The gap-filling capability also improved and there were no voids or seams in the 41 nm trench pattern. The proposed method can be an effective solution for fabrication of a conductive seed layer to fill a 41 nm trench pattern by electroplating.

  3. 铝粉表面超声波化学镀 Ni-Co 合金的研究%The Study of Ultrasonic Chemical Electroless Plating Ni-Co Alloy on the Surface of Aluminum Powder

    Institute of Scientific and Technical Information of China (English)

    李志广; 米伟娟; 俞梁

    2014-01-01

    Objective To study the plating of Ni-Co alloy layer on the surface of aluminum powder and to offer the basic raw material for preparing the new-type hollow ceramic microsphere microwave absorbing material. Methods The Ni-Co al-loy layer was prepared on the surface of aluminum powder by the ultrasonic chemical electroless plating method. Results The mass was increased by an average of 89. 0% after the aluminum powder was plated with Ni-Co alloy by ultrasonic chemical electroless plating. The SEM, EDS and XRD analyses showed that the Ni-Co alloy layer was formed on the sur-face of aluminum powder. Conclusion Ni-Co alloy layer could be formed on the surface of aluminum powder by the ultra-sonic chemical electroless plating method.%目的:在铝粉表面进行镀 Ni-Co 合金层的研究,为制备新型的空心陶瓷吸波材料提供基础原料。方法利用超声波化学镀法。结果铝粉经过超声波化学镀 Ni-Co 合金,质量增加平均百分率达到了89.0%,通过 SEM,EDS 和 XRD 分析,表明在铝粉表面形成了 Ni-Co 合金层。结论利用超声波化学镀法能够在铝粉表面形成 Ni-Co 合金层。

  4. SiC颗粒表面化学镀铜镀液工艺参数的优化设计%Optimization design of solution for electroless copper plating on the surface of SiC particle

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    In order to improve the wettability between the metal matrix and ceramic particle,the electroless copper plating technology was used to treat the SiC particle for improving the interface bonding capacity. The orthogonal design method was utilized to optimize plating parameters and the effect of solution parameters on the weight gain rate of SiC particle was discussed. The experimental results show that the weight gain rate of SiC particle increases after electroless copper plating when the concentration of CuSO4 and CH3CHO increases,while the weight gain rate gradually reduces with the concentration increase of the chelating agent. The homogeneous plating layers on the SiC particle can be obtained after the parameters optimization of electroless copper plating.%  针对金属基体与陶瓷颗粒之间润湿性差的问题,采用化学镀铜对SiC颗粒进行表面改性,试图提高其界面结合能力。采用正交试验方法优化化学镀铜参数,探讨镀液参数对复合粉体质量增加效果的影响。研究表明:化学镀铜过程中,随着硫酸铜浓度和甲醛浓度增加,镀后复合粉体质量增加率增加;随着络合剂浓度增加,质量增加率逐渐降低;化学镀铜参数优化后可实现SiC粉体表面化学镀铜层的均匀镀覆。

  5. 玻璃表面低磷化学镀镍研究%Electroless Nickel Plating of Low-Phosphorous on Glass

    Institute of Scientific and Technical Information of China (English)

    刘敏基; 胡志超; 丁毅; 秦铁男

    2011-01-01

    采用正交实验优化了玻璃表面低磷化学镀镍工艺,获得的最优组成为:柠檬酸钠15 g/L,氯化铵20 g/L,次磷酸钠30g/L,pH值8.采用扫描电镜(SEM)、能谱成分分析(EDS)和X射线衍射(XRD)等方法对镀镍层的表面形貌、镀层成分及物相结构进行了分析.结果表明:在最佳组成条件下所得的镀层具有致密的胞状组织,磷的质量分数为1.78%,属于低磷镀层,镀层为微晶态结构.%The process for electroless nickel plating of low-phosphorous on glass was optimized by orthogonal experiment. The optimal parameters obtained are: sodium citrate 15 g/L, ammonium chloride ZO g/L, sodium hypophosphite 30 g/L, pH 8.The morphology, composition and phase structure of the Ni-P deposit were analyzed by the XRD, SEM and EDX techniques.The results show that the Ni-P coating obtained under the optimal conditions has a compact cellular structure, of which the phosphorus mass fraction is 1. 78 %, belonging to low-phosphorous coating with a microcrystalline structure.

  6. Synthesis and characterization of LiNi0.49Mn1.49Y0.02O4@Ag by electroless plating technique

    Science.gov (United States)

    Xiong, Lizhi; Liu, Wenping; Wu, Yuxian; He, Zeqiang

    2015-02-01

    Silver (Ag) coated LiNi0.49Mn1.49Y0.02O4 (LiNi0.49Mn1.49Y0.02O4@Ag) was prepared by electroless plating method. The microstructure, surface morphology and electronic conductivity of LiNi0.49Mn1.49Y0.02O4@Ag were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and electronic conductivity tests. The results showed that 4 wt% silver was tightly coated in Ag0 state on the surface of LiNi0.49Mn1.49Y0.02O4 to form a uniform Ag-coating layer of about 30 nm. Electrochemical tests stated clearly that the cycling performance of LiNi0.49Mn1.49Y0.02O4@Ag was more stable and the rate capability was more outstanding than that of LiNi0.49Mn1.49Y0.02O4 due to the coating of Ag on the surface of LiNi0.49Mn1.49Y0.02O4 by improving the electronic conductivity, preventing LiNi0.49Mn1.49Y0.02O4 from being attacked by electrolyte, decreasing the electrochemical polarization during cycling and increasing the lithium ion diffusion coefficient on cathode materials.

  7. Direct electroless nickel plating on magnesium alloys and deposit properties%镁合金直接化学镀镍工艺及镀层性能

    Institute of Scientific and Technical Information of China (English)

    刘海萍; 夏文超; 毕四富; 李宁

    2011-01-01

    The optimal process conditions for direct electroless nickel plating on AZ31D magnesium alloy are as follows: nickel sulfate 14-22 g/L, sodium hypophosphite 20-28 g/L, citric acid 5-7 g/L, sodium acetate 9-17 g/L,ammonium hydrogen fluoride 8 g/L, hydrofluoric acid (volume fraction 40%) 12 mL/L, thiourea 2 mg/L, pH 6.2-6.4(adjusted with ammonia water), temperature 75-85 ℃ and deposition time 10-60 min. Under the given conditions, the deposit has the features of good appearance, strong adhesion to magnesium alloy substrate, high corrosion resistance, phosphorus content of 6%-10% and fast deposition rate.%AZ31D镁合金上直接化学镀镍的较佳工艺条件为:硫酸镍14~22g/L,次磷酸钠20~28 g/L,柠檬酸5~7 g/L,乙酸钠9~17 g/L,氟化氢铵8 g/L,40%(体积分数)的氢氟酸12 mL/L,硫脲2 mg/L,pH(用氨水调节)6.2~6.4,温度75~85℃,时间10~60 min.在此条件下获得的化学镀镍层外观良好,磷含量为6%~10%(质量分数),与镁合金基体结合牢固,耐蚀性能好且沉积速率较快.

  8. Development of nanoscale Ni-embedded single-wall carbon nanotubes by electroless plating for transparent conductive electrodes of 375 nm AlGaN-based ultraviolet light-emitting diodes

    Science.gov (United States)

    Park, Jun-Beom; Park, Hyung-Jo; Bae, Hyojung; Jeong, Tak; Han, Jong-Hun; Kwak, Joon Seop; Ha, Jun-Seok

    2016-08-01

    We propose a nanoscale Ni-embedded single-wall carbon nanotube (SWCNT) composite for transparent conductive electrodes (TCEs) of AlGaN-based ultraviolet light-emitting diodes (UV LEDs). TCEs specifically for the ultraviolet region were developed using Ni selectively electroless-plated SWCNTs. The nanoscale Ni of TCEs improved electrical conductivity and formed ohmic contact with p-GaN while minimizing transmittance loss. We applied Ni-embedded SWCNTs, SWCNTs, and Ni/Au to the TCEs of 375 nm UV LEDs. UV LEDs with Ni-embedded SWCNTs showed a 32% higher output power than UV LEDs with conventional Ni/Au TCEs.

  9. N,O-羧甲基壳聚糖在导电涤纶织物化学镀中的应用%Application of N,O-carboxymethyl chitosan in conductive polyester fabrics with electroless plating treatment

    Institute of Scientific and Technical Information of China (English)

    吴建文; 俞丹; 王炜

    2011-01-01

    对壳聚糖引入羧基制备改性N,O-羧甲基壳聚糖(NOCC),因其有良好的水溶性,可采用浸轧法处理在涤纶织物上,利用其在活化过程中吸附贵金属钯引发之后的化学镀,获得致密、均匀的金属镀层,赋予织物导电性和电磁屏蔽效能.采用红外图谱(FT-IR)和1℃核磁共振谱图对NOCC进行表征,并用SEM图观察了经NOCC处理后和化学镀后导电涤纶织物的纤维表面形貌.%Chitosan was modified with carboxyl to produce N,O-carboxymethyl chitosan (NOCC). Due to good water solubility, NOCC was treated on the polyester (PET) fabrics through padding method, which adsorbed precious palladium metal in the activation process and catalyzed the electroless plating process. Accordingly, compact and even metal plating was obtained, which endowed the fabric with electrical conductivity and electromagnetic shielding property. The structure of NOCC was characterized by FT-IR and 13C-NMR. The morphology of electrical conductive polyester fabric treated by NOCC and electroless plating was observed by SEM.

  10. Process optimization of electroless copper plating and its influence on electrochemical properties of AB5-type hydrogen storage alloy

    Institute of Scientific and Technical Information of China (English)

    ZHANG

    2010-01-01

    The amount of Cu coating by chemical plating was investigated based on quadratic regression orthogonal experimental design being adapted to the variation law of temperature,pH value and Ni2+concentration,and the relevant regression equation was expressed as y=2.1609+0.5295×10-3T2-0.0342P2-0.0265N2+0.0023TP+0.0020TH+0.0199PN-0.0959T+0.3814P-0.2073N.The results showed that the deposition rate augmented with the increasing in temperature,pH value and Ni2+concentration.The experimental parameters of the optimal coating were temperature 75 ℃,pH value 8.5 and Ni2+concentration 1.2 g/L.The electrochemical tests indicated that the cycle stability increased from 60.66% to 75.58%,indicating that the treated alloy exhibited better corrosion resistance.

  11. 化学镀Ni-P合金在铝合金表面强化上的应用%Application of Electroless Plating Ni-P Alloy on Aluminium Alloy

    Institute of Scientific and Technical Information of China (English)

    朱晓云; 郭忠诚; 翟大成

    2001-01-01

    研究了化学镀镍-磷合金的性能,结果表明,热处理温度对镍-磷合金镀层硬度和耐磨性有较大的影响,二者经400℃×1 h热处理后达到峰值;镍-磷合金在酸、碱、盐介质中的耐蚀性优于1Cr18Ni9Ti不锈钢。应用结果证明,化学镀Ni-P合金在铝合金零部件上具有广泛的应用前景。%Properties of electroless plating Ni-Palloy have been studied, the results show that heattreatment temperature has a considerable effect onthe hardness and wear resistance of Ni-P alloy, andthey reach peak value after heat treatment at 400 ℃X 1h. Corrosion resistance of Ni-P alloy in acid,alkaline and salt media is superior to that of1Cr18Ni9Ti stainless steel. The electroless platingNi-P alloy has a wide application for the componentof aluminium alloy.

  12. 化学镀非晶镍-磷合金分形分析%Fractal analysis on electrolessly plated amorphous nickel-phosphorus alloy

    Institute of Scientific and Technical Information of China (English)

    翁星星; 朱贤博

    2012-01-01

    Four Ni-P alloy coatings with different phosphorus contents were prepared by changing the concentration of sodium citrate as complexing agent in an electroless nickel plating bath consisting of NiSO4-6H2O, NaH2PO2-H2O, Na3C6H5O7, CH3COONa, and KIO3. The fractal dimension of the coating surface was calculated by projective covering method. The relationship between fractal dimension, sodium citrate concentration, and corrosion resistance in nitric acid was studied. The results showed that the fractal dimension is between 2.329 8 to 2.658 6 for the coatings, and has a good positive linear correlation with sodium citrate concentration but a negative linear correlation with corrosion weight loss in nitric acid. The quantitative characterization of corrosion resistance of coating by surface fractal dimension is feasible.%在由NiSO4·6H2O、NaH2PO2·H2O、Na3C6H5O7、CH3COONa和KIO3组成的化学镀镍液中,改变配位剂柠檬酸钠的浓度制备了4种不同含磷量的Ni-P合金镀层,用投影覆盖法计算了其表面分形维数,并考察了分形维数与柠檬酸钠浓度及镀层耐硝酸性能的关系.结果表明,镀层的表面分形维数介于2.329 8~2.6586之间,与柠檬酸钠浓度具有良好的线性正比关系,而与镀层在硝酸中的腐蚀失重量呈良好的线性负相关.因此,表面分形维数可用于定量表征镀层的耐蚀性.

  13. Research Progress of Conductive Composite Filler Prepared by Electroless Plating for Electromagnetic Shielding%化学镀制备电磁屏蔽用导电复合填料的研究进展

    Institute of Scientific and Technical Information of China (English)

    管登高; 孙传敏; 孙遥; 徐冠立; 林金辉; 陈善华

    2011-01-01

    The basic theory and main features about electroless plating are introduced. The situation of the research and development of metal coated conductive composite fillers with various sizes, densities, length-diameter ratios, conductivities, shielding properties and inoxidizabilities for electromagnetic shielding at home and abroad are emphatically reviewed, which are prepared using metal, inorganic nonmetallic and polymer powders as substrates by electroless plating. The advantages and disadvantages of these three types of metal coated conductive composite fillers are analyzed and compared. The main problems that exist at present such as electromagnetic impedance mismatch, low electromagnetic comprehensive performances and big surface property differences are pointed out. And the further study such as the compositions of the fillers, the technology and the formula of electroless plating are suggested in order to develop electromagnetic shielding composite fillers with higher performance-price ratios. This has very important significance and function to prevent and control electromagnetic radiation pollution.%介绍了化学镀的基本原理和主要特点,重点阐述了以金属、无机非金属、聚合物等粉料为基体,采用化学镀技术制备具有不同粒度、密度、长径比、导电性、电磁屏蔽效能和抗氧化性的电磁屏蔽用金属包覆型导电复合填料的国内外研究现状和进展.分析比较了这3类电磁屏蔽用导电复合填料的优缺点,指出其目前还存在电磁阻抗不匹配、电磁综合性能不高和表面性质差异过大的主要问题,建议今后还需进一步研究复合填料组成、化学镀配方和工艺等,以研制出性价比更高的电磁屏蔽用复合填料.

  14. Electroless Fabrication of Cobalt Alloys Nanowires within Alumina Template

    Directory of Open Access Journals (Sweden)

    Nazila Dadvand

    2007-01-01

    Full Text Available A new method of nanowire fabrication based on electroless deposition process is described. The method is novel compared to the current electroless procedure used in making nanowires as it involves growing nanowires from the bottom up. The length of the nanowires was controlled at will simply by adjusting the deposition time. The nanowires were fabricated within the nanopores of an alumina template. It was accomplished by coating one side of the template by a thin layer of palladium in order to activate the electroless deposition within the nanopores from bottom up. However, prior to electroless deposition process, the template was pretreated with a suitable wetting agent in order to facilitate the penetration of the plating solution through the pores. As well, the electroless deposition process combined with oblique metal evaporation process within a prestructured silicon wafer was used in order to fabricate long nanowires along one side of the grooves within the wafer.

  15. A Study of Electroless Nickel Plating with Citric Acid-Succinic Acid Double Complexing Agent System%柠檬酸-丁二酸双配位剂体系化学镀镍的研究

    Institute of Scientific and Technical Information of China (English)

    崔东; 刘定富

    2012-01-01

    Selection of complexing agent is one of the keys for electroless nickel plating technology. With two commonly used organic acids — citric acid and succinic acid as complexing agents, plating rate and mass fraction of phosphorus content in coating as evaluating indicator, their effects were investigated when they are used in separate and compounded forms on the basis of the single-factor experiment. The results show that single complexing agent is difficult to simultaneously satisfy the requirements of electroless nickel plating on plating rate and mass fraction of phosphorus content in coating while compounded use of complexing agents can overcome the difficulty between plating rate and mass fraction of phosphorus content in coating; when citric acid is 20 g/L and succinic acid 6 g/L. Plating rate is moderate, but the mass fraction of phosphorus content in coating is higher.%配位剂的选择是化学镀镍技术的关键之一.使用两种常用的有机酸——柠檬酸和丁二酸作为配位剂,以镀速和镀层中磷的质量分数为评价指标,先分别考察两者单独使用时的影响,然后在单因素实验的基础上,考察两者复配使用时的影响.结果表明:单一配位剂难以同时满足化学镀镍工艺对镀速和镀层中磷的质量分数的要求,配位剂复配使用可以克服镀速与镀层中磷的质量分数之间的矛盾;在柠檬酸20 g/L,丁二酸6 g/L的条件下,镀速适中且镀层中磷的质量分数较高.

  16. Vapour Treatment Method Against Other Pyro- and Hydrometallurgical Processes Applied to Recover Platinum From Used Auto Catalytic Converters

    Institute of Scientific and Technical Information of China (English)

    Agnieszka FORNALCZYK; Mariola SATERNUS

    2013-01-01

    Today more and more cars are produced every year.All of them have to be equipped with catalytic converters,the main role of which is to obtain substances harmless to the environment instead of exhausted gases.Catalytic converters contain platinum group metals (PGM) especially platinum,palladium and rhodium.The price of these metals and their increasing demand are the reasons why today it is necessary to recycle used auto catalytic converters.There are many available methods of recovering PGM metals from them,especially platinum.These methods used mainly hydrometallurgical processes; however pyrometallurgical ones become more and more popular.The article presents results of the research mainly concerning pyrometallurgical processes.Two groups of research were carried out.In the first one different metals such as lead,magnesium and copper were used as a metal collector.During the tests,platinum went to those metals forming an alloy.In other research metal vapours were blown through catalytic converter carrier (grinded or whole).In the tests metals such as calcium,magnesium,cadmium and zinc were applied.As a result white or grey powder (metal plus platinum) was obtained.The tables present results of the research.Processing parameters and conclusions are also shown.To compare efficiency of pyrometallurgical and hydrometallurgical methods catalytic converter carrier and samples of copper with platinum obtained from pyrometallurgical method were solved in aqua regia,mixture of aqua regia and fluoric acid.

  17. 石英光纤表面化学镀镍磷合金工艺%Electroless nickel-phosphor plating process on surface of quartz optical fiber

    Institute of Scientific and Technical Information of China (English)

    李小甫; 姜德生; 余海湖; 余丁山; 杨恩宇; 李鸿辉

    2005-01-01

    Quartz optical fibers are of great significance in many fields. For example, they can be used to fabricate strain sensors and temperature sensors. If the surface of optical fibers is metal-coated by the electroless plating method, the measuring precision and stability of the optical fiber sensors can be improved remarkably, additionally the life-span of sensors can be prolonged. In this work, an electroles snickel-phosphor plating process for optical fibers was presented. The influences of the content of NaH2PO2·H2O, bath pH value and temperature and the plating deposition rate on the quality of the plating coatings were studied with orthogonal testing. The results indicated that the content of NaH2PO2·H2O was the key factor, which influenced the adhesion force of the plating coatings. The nickel-phosphor plating bath presented in this work possessed excellent stability and the plating deposition rate could be accelerated. Using the process described in this work, nickel-phosphor coatings with great brightness and high adhesion force can be prepared successfully. Optimum conditions were: NiSO4 30g·L-1, NaH2PO2 ·H2O 20g·L-1, C3H6O3 4 ml·L-1, Na2CO3 3g·L-1 , NH4Cl 4g·L-1 , saccharin 1mg·L-1, temperature 84℃, pH 4.6.

  18. A Study of Electroless Silver Plating with Pd-Free Activation on Cenosphere%空心玻璃微珠无钯活化化学镀银的研究

    Institute of Scientific and Technical Information of China (English)

    朱国庆; 张瑾; 张辉

    2012-01-01

    基于银镜反应原理,不经过粗化和活化直接对空心玻璃微珠进行化学镀银.采用单因素分析法,研究了硝酸银、葡萄糖、装载量、氢氧化钠和无水乙醇对银的利用率以及镀层的增重率、导电性能和结合强度等的影响,并借助扫描电镜和X射线衍射仪对镀层的表面形貌和结构进行了分析.结果表明:与胶体钯活化工艺相比,无(钯)活化化学镀银工艺的银的利用率高,镀层均匀、致密,导电性好,结合强度高.%Based on the principle of silver mirror reaction, electroless silver plating was directly carried out on cenoshpere without pretreatments of coarsening and activation. The effects of silver nitrate, glucose, cenosphere loadage, sodium hydroxide and anhydrous alcohol on silver utilization ratio end the weight gain rate, conductivity, binding strength, etc. of the coating were investigated by single factor analysis. The surface morphology and structure of the coating were analyzed by SEM and XRD, The results indicate that as compared with colloidal palladium activation method, the silver utilization ratio is high, and the coating is uniform and compact with superior conductivity and high binding strength when the electroless silver plating process without palladium activation prelreatment is adopted.

  19. Development of Nickel Immersion Pretreatment of Electroless Nickel Plating on Al Alloy Surface%铝基化学镀镍浸镍前处理的研究进展

    Institute of Scientific and Technical Information of China (English)

    孙硕; 宋贡生; 马正华

    2015-01-01

    铝基表面欲获得结合力好的镀层,关键在于前处理工艺的选择. 尽管浸锌法是目前研究较多、效果较好的前处理方法,但仍存在一些不足,而浸镍法可以避免这些不足,有望取代浸锌法. 较详细地阐述了浸镍法的原理及研究现状,并将文献中涉及的浸镍法分为活化浸镍、碱性预镀镍和二次浸镍. 活化浸镍液中一般不含还原剂,主要通过置换反应生成一层具有催化作用的镍,进而促使化学镀过程中镍紧密均匀地沉积;碱性预镀镍则是通过含有还原剂的镍盐溶液,在铝基表面预化学镀上一薄层镍,其原理与化学镀镍相同. 同时,对比分析了两种浸镍法及其组合处理法之间的区别与联系. 最后,指出了浸镍法未来的发展方向:其一,简化工艺,用一次浸镍法代替二次浸镍法;其二,无毒、低污染,研发出无氟浸镍液;其三,获得高性能,即优化浸镍液配方,使得镀层与基体结合强度更好.%The key line to obtain electroless nickel plating with excellent adhesion to the substrate is the pretreatment process. The zincate treatment method as a pretreatment process has been studied by many researchers, and its effect is good. However, its disadvantages cannot be ignored. The nickel immersion method can avoid these shortages, and it is expected to replace zinc immer-sion method. The present article introduced the research status and the principle of zincate treatment. At the same time, this paper divided the relative zincate treatment into activation-nickel immersion method, alkaline elctroless nickel pre-plating method, and double nickel immersion method. The solution of activation-nickel immersion method normally does not contain reducing agent. This method produces a thin layer of nickel catalyst by substitution reaction, prompting the deposition of electroless nickel plating closely and evenly in the later process. The solution of alkaline nickel pre-plating is a kind of

  20. Preparation of Co/SiC Composite Particles Using Electroless Plating Method%化学镀法制备钴包覆碳化硅复合粉末的研究

    Institute of Scientific and Technical Information of China (English)

    周超兰; 张高科; 甘慧慧

    2011-01-01

    Electroless plating method was employed to prepare Co/SiC composite particles. In the process of electro-less deposition, the optimal conditions of electroless cobalt can be obtained through studying on the influence factors of the deposition rate, such as cobaltic salt concentration, deoxidizer concentration, complexing agent concentration, buffering agent concentration, temperature and pH value, etc. The composite particles were characterized by X-ray diffraction (XRD), Scanning electron microscope (SEM) and Energy dispersive x-ray analysis (EDAX). The experimental results indicate that the deposition rate is faster and the powder surface is coated by cobalt evenly when the concentration of sul-furic acid cobalt is varied form 30 g/L to 50 g/L, the concentration of sodium hypophosphite is set as 40 g/L, the concentration of sodium citrate is between 60 g/L and 70 g/L, the temperature is controlled in 50 ~ 70℃and pH value is adjusted as 8.%采用化学镀法制备钴包覆碳化硅复合粉末,通过研究化学镀过程中钴盐浓度、还原剂浓度、络合剂浓度、缓冲剂浓度、温度以及pH值等因素对沉积速率的影响规律,得到化学镀钴的优化条件.利用XRD、SEM和EDAX等测试手段对该复合粉末的组分及形貌进行了表征.实验和表征结果表明,当硫酸钴浓度为30~50 g/L,次磷酸钠浓度为40 g/L,柠檬酸钠浓度为60~70 g/L,控制温度为50~70℃以及调节pH值等于8时,镀层沉积速度较快,所得粉体表面被钴均匀包覆.

  1. 化学镀Ni-P-B合金中的动力学%Kinetics of Electroless Plating Ni-P-B Alloy

    Institute of Scientific and Technical Information of China (English)

    彭健

    2012-01-01

    Logarithmic relationship curves between the deposition rate and the concentration of reactants and operation temperature were obtained by experiments. Reaction kinetic parameters were obtained from comparison of experimental results and kinetic equations. Experimental equation of deposition rate can provide theoretical reference for electroless Ni-P-B alloy.%通过试验得到了化学镀Ni-P-B合金镀液中反应物浓度、温度等因素与沉积速率间的对数关系曲线,分别确定上述各因素对应的动力学参数,建立了沉积速率的经验方程式,计算了Ni-P-B合金化学镀的反应活化能。

  2. Electroless Deposition of Fe-Mo-W-B Amorphous Alloys

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The preparation, formation mechanism, surface appearance and structure of electroless plating Fe-Mo-W-B amorphous alloys were systematically studied. The deposition rates of the deposits in different bath composition as plated were measured. The formation mechanism of the deposits was discussed. The parameter for amorphous structures formation was suggested for the deposits.

  3. 柠檬酸-乳酸体系化学镀镍稳定剂的研究%A Study of Stabilizers for Citric Acid and Lactic Acid System Electroless Nickel Plating

    Institute of Scientific and Technical Information of China (English)

    彭庆康; 刘定富

    2012-01-01

    采用2巯基苯并噻唑(MBT)和2-巯基苯并咪唑(MB)作为稳定剂,以镀液稳定性和镀速为评价指标,考察了它们单独使用时及复配使用时的效果.结果表明:在柠檬酸乳酸化学镀镍体系中,MBT及MB均可单独作为稳定剂使用,且MB单独使用时的效果优于MBT的;MBT与MB复配具有一定的协同作用,效果优于其单独使用时的.%With 2-mercaptobenzothiazole (MBT) and 2-mercaptobenzimidazole (MB) as stabilizers, bath stability and plating rate as evaluation indicators, the effect of the stabilizers was investigated when they were used separately and in combination. The results show that in citric acid and lactic acid electroless nickel plating system, both MBT and MB can be used alone as stabilizer, and that MB is better than MBT in effect in separate use; MBT and MB, when compounded, have a certain synergistic effect, with a better effect than used separately.

  4. Study on preparation and performance of ultraviolet-curable active paste for electroless copper plating%紫外光固化化学镀铜活化浆料的制备及性能研究

    Institute of Scientific and Technical Information of China (English)

    曹权根; 陈世荣; 赖福东; 谢金平; 范小玲

    2015-01-01

    In order to prepare a silver-containing UV-curable active paste for electroless copper plating on the surface of PI (polyimide) thin film, the mixed potentialvs. time curves for electroless copper plating initiated by the active pastes obtained from different mass ratios of polyester acrylate to polyurethane acrylate were determined by electrochemical method, and the influence of the contents of silver nitrate and conductive carbon black on the adhesion and catalytic activity of the active paste and the conductivity of the copper deposit were studied. The surface morphology, structure, and silver distribution of the active paste and copper deposit were examined by scanning electron microscope (SEM), energy-dispersive X-ray spectrometer (EDS), and X-ray diffractometer (XRD). The active paste prepared with polyester acrylate and polyurethane acrylate at a mass ratio of 4 to 6 as composite prepolymers, conductive carbon black 10%, and AgNO3 7% was coated on PI thin film and then cured under UV irradiation. The copper deposit obtained by electroless copper plating for 10 min thereafter is fine-grained and compact with a 100% adhesion to the substrate and a square resistance of 0.046Ω/□.%为了在PI(聚酰亚胺)薄膜上制备一种含银的紫外光(UV)固化化学镀铜活化浆料,采用电化学方法测定了聚酯丙烯酸酯和聚氨酯丙烯酸酯不同质量比得到的活化浆料引发化学镀铜的混合电位–时间曲线,研究了硝酸银和导电炭黑含量对活化浆料的附着力、催化活性及铜镀层导电性的影响,通过扫描电镜(SEM)、X射线能谱仪(EDS)和X射线衍射仪(XRD)对活化浆料和铜镀层的表面形貌、结构以及Ag元素分布等进行了研究。以聚酯丙烯酸酯和聚氨酯丙烯酸酯按质量比为4∶6组成复合预聚体,导电炭黑和AgNO3的用量分别为10%和7%制备活化浆料,将其涂覆在PI薄膜上,UV固化后化学镀铜10 min,所得镀铜层颗粒细小、致

  5. Electroless alloy/composite coatings: A review

    Indian Academy of Sciences (India)

    R C Agarwala; Vijaya Agarwala

    2003-06-01

    Since the inception of electroless coating by Brenner & Riddell in 1946, it has been the subject of research interest and, in the past two decades, emphasis has shifted to the studies of its properties and applications. The co-deposition of particulate matter or substance within the growing film has led to a new generation of electroless composite coatings, many of which possess excellent wear and corrosion resistance. This valuable process can coat not only electrically conductive materials including graphite but also fabrics, insulators like plastics, rubber etc. The low coating rates with these can provide better reflectivity of plated surfaces and many more applications. Coatings can be tailored for desired properties by selecting the composition of the coating alloy/composite/metallic to suit specific requirements. The market for these coatings is expanding fast as the potential applications are on the rise. In the present article, an attempt has been made to review different electroless alloy/composite coatings with respect to bath types and their composition, properties and applications. Different characterisation studies have been conducted on various electroless nickel-based coatings with emphasis on wear and corrosion properties.

  6. Passive auto-catalytic recombiners operation in the presence of hydrogen and carbon monoxide: Experimental study and model development

    Energy Technology Data Exchange (ETDEWEB)

    Klauck, Michael, E-mail: klauck@lrst.rwth-aachen.de [RWTH Aachen University, Institute for Reactor Safety and Reactor Technology, 52072 Aachen (Germany); Reinecke, Ernst-Arndt, E-mail: e.reinecke@fz-juelich.de [Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research – Nuclear Waste Management and Reactor Safety (IEK-6), 52425 Jülich (Germany); Kelm, Stephan, E-mail: s.kelm@fz-juelich.de [Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research – Nuclear Waste Management and Reactor Safety (IEK-6), 52425 Jülich (Germany); Meynet, Nicolas, E-mail: nicolas.meynet@irsn.fr [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSN-RES/SAG/BPhAG, BP 17 92262 Fontenay aux Roses (France); Bentaïb, Ahmed, E-mail: ahmed.bentaib@irsn.fr [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSN-RES/SAG/BPhAG, BP 17 92262 Fontenay aux Roses (France); Allelein, Hans-Josef, E-mail: allelein@lrst.rwth-aachen.de [RWTH Aachen University, Institute for Reactor Safety and Reactor Technology, 52072 Aachen (Germany); Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research – Nuclear Waste Management and Reactor Safety (IEK-6), 52425 Jülich (Germany)

    2014-01-15

    Highlights: • We studied the hydrogen conversion in the presence of carbon monoxide (CO). • CO recombines at a lower efficiency than hydrogen. • Under the given conditions, hydrogen conversion is not affected by CO. • We used three different numerical codes to simulate the experimental findings. • All codes are reproducing the experimental data well. -- Abstract: In a LWR severe accident, carbon monoxide (CO) may be generated inside the containment due to molten corium concrete interaction (MCCI). As a component of the accident atmosphere, CO will interact with passive auto-catalytic recombiners (PARs) which are installed inside LWR containments for hydrogen (H{sub 2}) removal. Depending on the boundary conditions, CO may either react with oxygen to carbon dioxide (CO{sub 2}) or act as catalyst poison, reducing the catalyst activity and hence the hydrogen conversion efficiency. A new experimental test programme performed in co-operation between JÜLICH and RWTH investigates these aspects aiming at providing data for model development for advanced severe accident analyses. In the first test series presented here, the parallel catalytic reaction of H{sub 2} and CO on the catalyst surface has been studied, i.e. the hydrogen recombination reaction was started before CO was injected. In total, 33 steady state measurements have been performed. The test series was jointly evaluated by JÜLICH, RWTH and IRSN. The test results show that under the given conditions the conversion of CO into CO{sub 2} has no negative impact on the parallel hydrogen conversion. The efficiency of the CO recombination in terms of molar rates is significantly smaller (by a factor of ∼2) than the corresponding H{sub 2} conversion efficiency. Due to the exothermal reaction, the parallel CO conversion may also have an impact on the possible ignition of the flammable gases at hot PAR surfaces. The authors have used three different numerical codes for the simulation of the parallel CO

  7. 镍钴化学镀碳纳米管的表征及其吸波性能%Characterization of electroless nickel-cobalt plated carbon nanotube and its wave-absorbing performance

    Institute of Scientific and Technical Information of China (English)

    刘晓霞; 李巧玲; 武润平; 续丽丽; 万郁楠; 李洪刚; 朱灿

    2013-01-01

    以银氨溶液为敏化活化剂,采用一步敏化活化化学镀工艺制备了纳米镍钴包覆碳纳米管(CNTs)复合材料.通过正交试验考察了镀液pH、温度、镍钴摩尔比对CNTs在低频区吸波性能的影响,确定了最佳工艺条件为:温度70℃,pH=9,n(Ni)/n(Co)=3∶7.通过透射电镜(TEM)、扫描电镜(SEM)、能谱分析(EDS)和X射线衍射(XRD)等方法对化学镀前后碳纳米管进行了表征.结果表明,镍钴成功地包覆在碳纳米管上;在最佳条件下制得的镍钴碳纳米管的最大回损值达到-30.66 dB,吸波值小于-5 dB的频率宽度为1 042 MHz.该镍钴碳纳米管是一种极具潜力的吸波材料.%A composite material of nano-nickel-cobalt coated carbon nanotubes (CNTs) was prepared by electroless plating after one-step sensitization/activation process using silver ammonia solution as sensitizer and activator.The effects of bath pH,temperature,and molar ratio of nickel to cobalt on the microwave-absorbing property of CNTs in low frequency region were studied by orthogonal test.The optimal process conditions were determined as follows:temperature 70 ℃,pH 9,and Ni-to-Co molar ratio 3:7.The carbon nanotubes before and after electroless plating were characterized by transmission electron microscopy (TEM),scanning electron microscopy (SEM),energy-dispersive spectroscopy (EDS),and X-ray diffraction (XRD).The results indicated that nickel-cobalt alloy was successfully coated on the surface of carbon nanotubes.The maximum reflection attenuation value of the nickel--cobalt coated carbon nanotubes obtained under the optimum conditions reaches-30.66 dB,and the frequency width in wave-absorbing value less than-5 dB is 1 042 MHz.The nickel-cobalt coated carbon nanotube is a potential wave-absorbing material.

  8. 光亮剂对酸性中磷化学镀镍层性能的影响%Effect of brightening agent on properties of medium-phosphorus nickel coating deposited by acidic electroless plating

    Institute of Scientific and Technical Information of China (English)

    杨倩韵; 郑文芝; 张晓明; 鹿轩; 林继月; 陈姚; 于欣伟

    2016-01-01

    The effects of four kinds of brightening agents, i.e. 3-N,N-diethylamino-1-propyne formate (DEP), copper sulfate, composite brightener RS, and sodium saccharin on properties of the medium-phosphorus Ni-P alloy coating deposited from an acidic electroless nickel plating bath were studied by polarization curve measurement, scanning electron microscopy (SEM), neutral salt spray (NSS) test, and other methods. The results showed that the coating obtained with copper sulfate as brightening agent has the highest brightness and a mirror-like surface with an average roughness (Ra) of 0.78μm, but the worst corrosion resistance. The fastest deposition rate was obtained as 21.56μm/h when using sodium saccharin as a brightening agent. The coating deposited by adding the RS intermediate to plating bath shows the best corrosion resistance and a relative good brightness.%采用极化曲线、扫描电子显微镜(SEM)、中性盐雾(NSS)试验等方法,研究了酸性中磷化学镀镍液中N,N?二乙基丙炔胺甲酸盐(DEP)、硫酸铜、复配光亮剂RS和糖精钠4种光亮剂对镀层性能的影响.结果表明,以硫酸铜作为光亮剂所获得的镀层光亮度最高,镀层表面粗糙度(Ra)平均值达0.78μm且呈镜面状态,但镀层耐蚀性最差;用糖精钠作光亮剂时镀速最快,达21.56μm/h;而加入中间体RS的镀层耐蚀性最好,且光亮度较好.

  9. Fabrication of metal coated carbon nanotubes by electroless deposition for improved wettability with molten aluminum

    OpenAIRE

    Arai, Susumu; Suzuki, Yosuke; Nakagawa, Junshi; Yamamoto, Tohru; Endo, Morinobu

    2012-01-01

    Ni-P alloy coated and Au/Ni-P alloy double-coated multiwalled carbon nanotubes (MWCNTs) were fabricated using electroless plating. Three types of electroless Ni-P alloy plating baths were prepared to coat the MWCNTs with Ni-P alloy films of varying phosphorus content. Electroless gold coating of the Ni-P alloy coated MWCNTs was also carried out using a non-cyanide bath. The microstructures of the coatings on the MWCNTs were examined by scanning electron microscopy and X-ray diffraction. The w...

  10. Synthesis and characterization of LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4}@Ag by electroless plating technique

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Lizhi; Liu, Wenping; Wu, Yuxian; He, Zeqiang, E-mail: csuhzq@163.com

    2015-02-15

    Highlights: • LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4} cathode materials have been synthesized by citric acid-assisted combustion method. • LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4}@Ag cathode materials with 4 wt% silver in Ag{sup 0} state coating layer on the surface of LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4} have been prepared by electroless plating technique. • The Ag-coating improves the electronic conductivity and the surface stability of LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4}. • LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4}@Ag exhibit enhanced cycling stability and rate capability. - Abstract: Silver (Ag) coated LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4} (LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4}@Ag) was prepared by electroless plating method. The microstructure, surface morphology and electronic conductivity of LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4}@Ag were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and electronic conductivity tests. The results showed that 4 wt% silver was tightly coated in Ag{sup 0} state on the surface of LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4} to form a uniform Ag-coating layer of about 30 nm. Electrochemical tests stated clearly that the cycling performance of LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4}@Ag was more stable and the rate capability was more outstanding than that of LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4} due to the coating of Ag on the surface of LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4} by improving the electronic conductivity, preventing LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4} from being attacked by electrolyte, decreasing the electrochemical polarization during cycling and increasing the lithium ion diffusion coefficient on cathode materials.

  11. AZ31变形镁合金化学镀前无铬酸洗工艺研究%An Investigation of Chromium-Free Pickling Process for Electroless Nickel Plating on AZ 31 Wrought Magnesium Alloy

    Institute of Scientific and Technical Information of China (English)

    秦铁男; 马立群; 贺忠臣; 姚妍; 丁毅

    2011-01-01

    主要研究了AZ 31变形镁合金化学镀前的磷酸-硝酸-氢氟酸混合酸洗工艺及各组分对镁合金基体的腐蚀失重表面形貌、镀层与基体的截面形貌和结合力的影响.结果表明:氢氟酸的加入可以有效降低酸洗反应速率并防止新鲜的镁合金基体表面的再次氧化;硝酸的体积分数对镁合金表面形貌的改变有较大影响;当磷酸-硝酸-氢氟酸的体积分数分别为300 mL/L,60 mL/L和100 mL/L时,镀层与基体的结合力最好.%A phosphoric acid-nitric acid-hydrofuoric acid mixed acid pickling process was studied for electroless nickel plating on AZ 31 wrought magnesium alloy sheet. The effects of pickle components on corrosion weight loss, surface morphology, cross section morphology and adhesion strength between the substrate and coating were investigated. The results show that addition of hydrofluoric acid can effectively reduce the rate of pickling reaction and protect the fresh substrate from being Oxidized again. The volume fraction of nitric acid has a great impact on changes of the surface morphology of magnesium substrate. The best adhesion strength between the substrate and the coating is achieved when the pickle solution contains 300 mL/L phosphoric acid, 60 mL/L nitric acid and 100 mL/L hydrofluoric acid.

  12. NdFeB磁性材料表面化学镀Ni-W-P合金研究%Electroless Ni-W-P plating alloy on the surface of the NdFeB permanent magnets

    Institute of Scientific and Technical Information of China (English)

    刘炜; 王憨鹰

    2011-01-01

    通过不同的化学镀工艺配方,在NdFeB永磁体表面获得4种不同W含量的化学镀Ni-W-P三元合金镀层.利用SEM对镀层的微观组织观察与分析表明:镀层表面形貌呈致密胞状结构,Ni、W、P元素分布均匀.进一步的衍射分析和硬度测试表明:随镀层中W和P元素含量的不同,镀层结构分别由纳米晶态、混晶态和非晶态组成,镀层的硬度随镀层结构从非晶态-混晶态-晶态的转变而增加.%Four ternary Ni-W-P alloy coatings on the surface of the Nd-Fe-B permanent magnet with different W contents were obtained by four different electroless Ni-W-P plating bath. The SEM observation and analysis of the coatings indicate that the morphology appeares closely nodules structure, and Ni, Cu, P elements distribute homogeneously in the coatings. The X-ray diffraction analysis and the hardness measurement suggest that with the changing of W and P content, the coating structures are crystalline, mixed crystalline and amorphous respectively. And the hardness of coatings also increases with its structure changing from amorphous into mixed crystalline and crystalline.

  13. Ultrasound influence on the activation step before electroless coating.

    Science.gov (United States)

    Touyeras, F; Hihn, J Y; Delalande, S; Viennet, R; Doche, M L

    2003-10-01

    This paper is devoted to the electroless plating of non-conductive substrates under ultrasound at 530 kHz. The ultrasonic irradiation is applied to the activation and to the plating steps. Effects are measured by following the final copper thickness obtained in 1 h of plating time, easily correlated to the average plating rate. It appears that ultrasound has a strong influence on the plating rates enhancement, and assumptions can be made that this increase could be linked to the catalyst cleaning. This is confirmed by XPS measurements. PMID:12927613

  14. Study on Electroless Nickel Plating for Surface Modification of Carbon Fiber%碳纤维化学镀镍表面改性研究

    Institute of Scientific and Technical Information of China (English)

    姚怀; 郭军华; 崔文聪; 董伟学; 詹海娇

    2014-01-01

    Objective To perform nickel coating on the surface of carbon fiber using chemical deposition under ultrasonic condi-tion so as to study nickel plating for surface modification of carbon fiber. Methods The organizational structure,microstructure and plating rate were changed by the pH value of plating bath and temperature of heat treatment as well as ultrasound, which were in-vestigated through XRD and SEM analysis. Results When the pH value was between 8. 0 and 10. 0, the deposition rate was in-creased with the pH value, the coating was uniform, dense and well bonded with the matrix and the coating thickness was about 0. 5 μm. The carbon fiber had a reunion phenomenon, when the pH value was between 10. 0 ~ 11. 0. The plating layer was recrys-tallized to generate Ni3 P phase after being kept for 10 min at the heat treatment temperature of 400 ℃ . With increasing of the tem-perature, the plating layer crazed and the gap between the crazed parts decreased. Conclusion The pH value had great influence on deposition and would lead to carbon fiber reunion when exceeding the limit value. Too high temperature for heat treatment would lead to recrystallization and crack of the plating layer.%目的:在碳纤维表面进行化学镀镍,对碳纤维化学镀镍的表面改性进行研究。方法通过 X 射线衍射仪、扫描电子显微镜等测试手段研究 pH 值、热处理温度及超声波对镀层的形貌、组织结构及镀速的影响。结果 pH 值在8.0~10.0时,随 pH 值增大,沉积速率逐渐变大,镀层表面均匀致密,与基体结合良好,厚度约为0.5μm;pH 值在10.0~11.0时,碳纤维发生团聚。热处理温度为400℃时,保温10 min,镀层重结晶析出 Ni3 P 相;随温度升高,镀层发生开裂,且开裂部位间隔变小。结论 pH 值对镀层沉积影响较大,超过极限值会导致碳纤维团聚。热处理温度过高会导致镀层重结晶,且发生开裂。

  15. Research progress of electroless plating applied on heat exchange surface to enhance dropwise condensation,anti-fouling and anti-corrosion properties%化学镀在换热表面强化滴状凝结、阻垢、耐蚀研究进展

    Institute of Scientific and Technical Information of China (English)

    胡丞; 高景山; 张英

    2015-01-01

    Based on the practical problems of condenser,this article reviews the research progress of electroless plating applied to enhance dropwise condensation,anti-fouling and anti-corrosion properties.It is discussed the influence of surface energy,amorphous content,temperature, pressure,and PTFE content on the dropwise condensation.The growth of deposition on the electroless plating surface is introduced,and it is discussed the effect of amorphous content, experiment conditions,multi-layer plating and wolfram,boron nitride,stannum and cooper content on the surface anti-fouling property.This article discusses the influence of phosphorus content,multi-layer plating,surfactant,pH,temperature and Cu and PTFE content on the surface anti-corrosion property.Considering practical problems of condenser, put forward to future research which is creating a muli-property electroless plating.Meanwhile,in order to promote the development of electroless plating technology industrialization,longevity problem of electroless plating should also be solved.%从换热器实际问题出发,分别回顾了化学镀层强化凝结换热、阻垢、耐蚀3个方面的研究进展。在强化凝结换热方面,阐述了以 Ni-P化学镀为基础的界面表面能、镀层非晶含量、温度、压力以及添加 PTFE等物质对在换热界面形成滴状凝结的影响。在化学镀阻垢方面,介绍了污垢的生长过程,讨论了镀层非晶含量、实验条件、梯度镀层以及添加W、BN、Sn、Cu等元素对镀层阻垢性能的影响。在化学镀耐腐蚀研究方面,阐述了镀层磷含量、梯度镀层、表面活性剂、镀液 pH 值、温度以及添加Cu、PTFE等元素对镀层抗腐蚀性能的影响。并根据实际生产情况,提出对镀层强化凝结换热、阻垢和耐腐蚀3个方面特性相互间的影响关系进行研究。同时提出,为了推进镀层技术工业化发展,还应解决镀层长效性的问题。

  16. Electroless plating of Ag-TiO2 nanoparticle composite on PET fabric%涤纶织物纳米TiO2颗粒化学复合镀银

    Institute of Scientific and Technical Information of China (English)

    凌明花; 张辉

    2011-01-01

    采用化学镀技术,实现了不同分散剂分散纳米TiO2颗粒涤纶织物表面化学复合镀银,借助SEM、XRD和TG对镀层表面形貌、结构和织物热性能进行研究,测试织物的电磁波屏蔽、导电、耐磨、透气和光催化性能.结果表明:用PVP&T80作分散剂时,纳米TiO2的引入对镀层结构没有影响,但晶粒尺寸增大;随着纳米TiO2质量浓度的增加,镀速先上升后降低然后再上升;当增重率相同时,较化学镀银织物,纳米TiO2化学复合镀银织物热学性能没有明显变化,耐磨性增强,透气性下降;当纳米TiO2质量浓度小于0.25 g/L时,电磁波屏蔽性能有所提高,可以降解亚甲基橙染料.%TiO2 nanoparticles were firstly dispersed by using different dispersants, and then was added to the solution of silver ammonia. The Ag-TiO2 composite coating on PET fabric was performed by electroless plating. The morphology, structure, and thermal property of the Ag-TiO2-coated fabric was characterized using SEM, EDX, XRD and TG. The electromagnetic shielding effectiveness, electrical conductivity, abrasion resistance, air permeability and degradation of methylene orange dye under UV irradiation of the fabric were investigated. It was found that the introdution of TiO2 nanoparticles had no effect on the structure of the Ag coating when PVA and Tween 80 were used as dispersant. But the crystal size increased. With the increase of the mass concentration of TiO2 nanoparticles, the plating rate increased at first, then decreased and increased at last. As compared with the Ag-plated fabric, the onset decomposition temperature of the Ag-TiO2-plated fabric did not change when the weighting percentage was identical. However, the abrasion resistance was increased and air permeability was decreased. The electromagnetic shielding effectiveness was improved when the mass concentration of TiO2 nanoparticles was below 0. 2 g/L. The capability of photocatalytic degradation of methylene

  17. Effects of Sodium Citrate Concentration on Electroless Ni-Fe Bath Stability and Deposition

    Science.gov (United States)

    Jung, Myung-Won; Kang, Sung K.; Lee, Jae-Ho

    2014-01-01

    In this research, electroless Ni-Fe bath stability and deposition characteristics were investigated for various sodium citrate concentrations. Complexing agents such as sodium citrate are one of the main components of such electroless plating baths. Since they could play various roles such as maintaining pH stability, preventing precipitation of metal salts, and reducing the concentrations of free metal ions, the concentration of complexing agents in the plating bath is an important parameter for electroless deposition processes. In this research, unstable baths were obtained for insufficient sodium citrate concentrations, and these phenomena were analyzed with ChemEQL. Moreover, the deposition characteristics of electroless Ni-Fe for under bump metallurgy diffusion barriers were also investigated using energy-dispersive spectroscopy and field-emission scanning electron microscopy.

  18. Influences of pH Value on Electroless Sliver Plating on PET Fabrics%pH值对涤纶织物化学镀银的影响

    Institute of Scientific and Technical Information of China (English)

    徐文龙; 徐勤; 邹奉元; 熊杰

    2011-01-01

    Eletroless sliver plating using glucose as reducing agent and ammonia as complexing agent were studied. Surface morphology, chemical composition and crystal structure of sliver-coated fabric were characterized by means of FE-SEM, EDS and XRD. Influences of pH value on the stability of solution, surface morphology, chemical composition, crystal structure, deposition rate, mass gain, surface resistance and electromagnetic interference shielding effectiveness (EMI SE) were also investigated. Results reveal that the high pH value leaded to the low stability. of solution and high deposition rate. Crystallite size increases firstly, then decreases and preferred orientation of (111 ) plane decreases, preferred orientation of (220) and (311 ) plane increases with the increase of pH value. Tight deposit, fine crystal structure and high EMI SE are obtained when pH value is 12.8.%研究了用葡萄糖作还原剂、氨水作络合剂在平纹涤纶织物上的化学镀银.分别采用场发射电镜(FE-SEM)、电子能谱(EDS)和X射线衍射(XRD)表征化学镀银层的表面形貌、镀层成分及结晶情况.考察了pH值对化学镀银镀液稳定性、镀层表面形貌、化学成分、结晶情况、镀银速率、增重率、表面电阻以及电磁屏蔽效能的影响.结果表明:pH值对化学镀银有非常重要的影响,pH值越高,溶液稳定性越差,镀银速率越快;随着pH值的升高,银的晶粒尺寸先增大后减小,晶面(111)的择优取向降低,晶面(220),(311)的择优取向升高.当pH值为12.8时,镀层堆积紧密、结晶性和电磁屏蔽效能较好.

  19. Growth behavior of electroless copper on silicon substrate

    Institute of Scientific and Technical Information of China (English)

    Shin-Shyan Wu; Wei-Long Liu; Ting-Kan Tsai; Shu-Huei Hsieh; Wen-Jauh Chen

    2007-01-01

    The growth behavior containing deposit morphology,growth rate,activation energy,and growth mechanism of copper on silicon substrate,especially at the initial stage,in the electroless plating process was studied.Copper was deposited on the surface of the silicon substrate in an electroless plating bath containing formalin (CH2O 37vol%) as a reducing agent at a pH value of 12.5 and a temperature of 50-75 ℃.The copper deposit was characterized using a field emission scanning electron microscope and transmission electron microscope.The results showed that after the activation process,nanoscale Pd particles were distributed evenly on the surface of the silicon; in the deposition process,copper first nucleated at locations not only near the Pd particles but also between the Pd particles;the growth rate of electroless Cu ranged from 0.517 nm/s at 50 ℃ to 1.929 nm/s at 75 ℃.The activation energy of electroless Cu on Si was 52.97 kJ/mol.

  20. Direct electroless Ni-P deposition on AM50 magnesium alloy from sulfate bath

    Institute of Scientific and Technical Information of China (English)

    LI Guang-yu; NIU Li-yuan; JIANG Zhong-hao; GU Chang-dong; LIAN Jian-she

    2006-01-01

    A bright electroless Ni-P deposition on AM50 magnesium alloy in a sulfate plating bath was proposed by using direct plating process with non-chromate pretreatment. The electroless Ni-P plating on AM50 magnesium alloy has an admirable appearance and good adhesion. The results indicate that the electroless Ni-P deposition with non-chromate pretreatment has better adhesion than that of zinc immersion coating. Anodic polarization curves indicate that the electroless Ni-P deposition obtained from the sulfate bath has similar corrosion-resistance to that obtained from basic nickel carbonate bath. The deposition process generates less pollutant by a non-chromate plating bath and is suitable for the magnesium alloys manufacture because of its low cost. The hardness of the electroless Ni-P plated AM50 is about HV 720.6 and HV 969.7 after heat treatments at 180 ℃ for 2 h. The wear resistance of Ni-P plated magnesium alloy specimens is about 5 to 9 times as high as that of bare magnesium alloys.

  1. ELECTROLESS NICKEL DEPOSITION ON FRAXINUS MANDSHURICA VENEER MODIFIED WITH APTHS FOR EMI SHIELDING

    OpenAIRE

    Haibing Liu; Lijuan Wang

    2010-01-01

    Electroless nickel deposition was carried out on Fraxinus mandshurica veneers for EMI shielding under a new activation process. In the process, Pd(II) was absorbed on the surface of veneers modified with γ-aminopropyltrihydroxysilane (APTHS) obtained from the hydrolysis of γ-aminopropyltriethoxysilane (APTES). After the reduction, electroless plating was successfully initiated, and Ni-P coating was deposited on the veneers. The activation process and resulting coating were characterized by XP...

  2. A novel Ag catalyzation process using swelling impregnation method for electroless Ni deposition on Kevlar® fiber

    Science.gov (United States)

    Pang, Hongwei; Bai, Ruicheng; Shao, Qinsi; Gao, Yufang; Li, Aijun; Tang, Zhiyong

    2015-12-01

    A novel Ag catalyzation process using swelling impregnation pretreatment method was developed for electroless nickel (EN) deposition on Kevlar fiber. Firstly, the fiber was immersed into an aqueous dimethylsulfoxide (DMSO) solution of silver nitrate to impart silver nitrate into the inner part of the fiber near the surface. Subsequently silver nitrate was reduced to metal silver nanoparticles on the fiber surface by treatment with aqueous solution of sodium borohydride. After electroless plating, a dense and homogeneous nickel coating was obtained on the fiber surface. The silver nanoparticles formed at the fiber surface functioned as a catalyst for electroless deposition as well as an anchor for the plated layer. The study also revealed that the incorporation of surfactant sodium dodecyl sulfate (SDS) in electroless nickel plating bath can enhance the adhesion strength of EN layer with the fiber surface and minimize the surface roughness of the EN coating. The Ni plated Kevlar fiber possessed excellent corrosion resistance and high tensile strength.

  3. Preparation of copper-coated fine molybdenum powders with electroless technique

    Institute of Scientific and Technical Information of China (English)

    WANG Guang-jun; WANG De-zhi; ZHOU Jie; WU Zhuang-zhi

    2009-01-01

    The molybdenum powders with average particle size of 3 μm were coated with copper by electroless plating. The influence of pretreatment, solution composition and plating conditions on electroless copper plating was studied. The copper-coated molybdenum powders were examined by SEM and XRD. Results indicate that a series of optimization methods is used to add activated sites before electroless copper plating. Taking TEA and EDTA as chief and assistant complex agents respectively, 2,2'-bipyridyl and PEG as double stabilizers, the Mo powders are coated with copper successfully with little Cu2O contained, at the same time, Mo-Cu composite powders with copper content of 15 - 85 wt% can be obtained. The optimal values of pH, temperature and HCHO concentration are 12- 13, 60-65 ℃ and 22-26 mL/L, respectively.

  4. Electroless synthesis of cellulose-metal aerogel composites

    Science.gov (United States)

    Schestakow, M.; Muench, F.; Reimuth, C.; Ratke, L.; Ensinger, W.

    2016-05-01

    An environmentally benign electroless plating procedure enables a dense coating of silver nanoparticles onto complex cellulose aerogel structures. In the course of the nanoparticle deposition, the morphological characteristics of the aerogel are preserved, such as the continuous self-supporting network structure. While achieving a high metal loading, the large specific surface area as well as the low density is retained in the cellulose-metal aerogel composite. Due to the interesting features of cellulose aerogel substrates (e.g., the accessibility of its open-porous network) and electroless plating (e.g., the possibility to control the density, size, and composition of the deposited metal nanoparticles), the outlined synthetic scheme provides a facile and flexible route towards advanced materials in heterogeneous catalysis, plasmonics, and sensing.

  5. Preparation and electricity performance of silver coating glass frit by electroless silver plating%化学镀制备银包覆玻璃粉及其电学性能

    Institute of Scientific and Technical Information of China (English)

    杨超; 甘卫平; 周健; 黎应芬; 鲁志强; 戈田田

    2015-01-01

    Glass frits were activated through ethylene glycol reducing AgNO3, nano-silver coated glass frits composite powders were prepared by electroless plating method using glucose as reducing reagent and silver-ammonia solution as precurso. The microstructures and phase composition of glass frits coated silver were characterized by SEM, EDS and XRD. The effects of ethylene glycol activating and concentration of AgNO3 on silver coating were studied when pH of the solution is 13.0. The results show that, nano-silver coating is uniform when the concentration of silver nitrate and glucose are 0.057 mol/L and 0.088 mol/L. The polycrystalline silicon solar cells were prepared using ordinarily and modified glass frits, respectively. Compared with silver slurry made up by ordinarily glass frits, the face side silver slurry made up by modified glass frits can densified electrode grids and the translational ratio of sunlight to electricity increases from 17.45%to 17.51%.%采用乙二醇还原硝酸银工艺对玻璃粉进行活化处理,再以银氨溶液为前驱体、葡萄糖为还原剂,用化学镀法在玻璃粉表面镀覆纳米银层,得到 Ag/玻璃复合粉末。利用 X 射线衍射、扫描电镜及能谱分析等方法研究Ag/玻璃复合粉末的结构与成分,并在溶液 pH 值约为13.0的条件下,分别研究乙二醇活化与镀液中的硝酸银浓度c(AgNO3)对银镀层的影响。结果表明,在活化基础上,当c(AgNO3)为0.057 mol/L,葡萄糖浓度为0.088 mol/L时,得到均匀的纳米银镀层。分别采用普通玻璃粉与改性玻璃粉配制正面银浆,进一步制备多晶硅太阳能电池片,与普通玻璃粉相比,用镀银玻璃粉配制的正面银浆可以致密栅线,电池的光电转换效率从17.45%提高到17.51%。

  6. Study of the Electroless Deposition of Ni for Betavoltaic Battery Using PN Junction without Seed Layer

    Directory of Open Access Journals (Sweden)

    Jin Joo Kim

    2015-01-01

    Full Text Available The method and conditions of Ni plating were optimized to maximize the output of a betavoltaic battery using radioactive 63Ni. The difference of the short circuit currents between the pre- and postdeposition of 63Ni on the PN junction was 90 nA at the I-V characteristics. It is suspected that the beta rays emitted from 63Ni did not deeply penetrate into the PN junction due to a Ni seed layer with a thickness of 500 Å. To increase the penetration of the beta rays, electroless Ni plating was carried out on the PN junction without a seed layer. To establish the electroless coating conditions for 63Ni, nonradioactive Ni was deposited onto a Si wafer without flaws on the surface. This process can be applied for electroless Ni plating on a PN junction semiconductor using radioactive 63Ni in further studies.

  7. Start-up behaviour of a passive auto-catalytic recombiner under counter flow conditions: Results of a first orienting experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Berno, E-mail: simon@lrst.rwth-aachen.de [RWTH Aachen University, Institute for Reactor Safety and Reactor Technology (LRST), 52072 Aachen (Germany); Reinecke, Ernst-Arndt, E-mail: e.reinecke@fz-juelich.de [Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research – Nuclear Waste Management and Reactor Safety (IEK-6), 52425 Jülich (Germany); Kubelt, Christian, E-mail: kubelt@lrst.rwth-aachen.de [RWTH Aachen University, Institute for Reactor Safety and Reactor Technology (LRST), 52072 Aachen (Germany); Allelein, Hans-Josef, E-mail: allelein@lrst.rwth-aachen.de [RWTH Aachen University, Institute for Reactor Safety and Reactor Technology (LRST), 52072 Aachen (Germany); Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research – Nuclear Waste Management and Reactor Safety (IEK-6), 52425 Jülich (Germany)

    2014-10-15

    Highlights: • We studied the start-up behaviour of a PAR located in a downward-directed flow. • We performed several identical experiments with and without counter flow. • A temporary interference of the establishing chimney flow is observed. • An earlier local start-up of the catalytic reaction occurs under downward flow. • The overall performance of the PAR is not significantly affected. - Abstract: A downward directed wall-near flow represents a typical thermal hydraulic condition inside the LWR containment during a severe accident. In order to efficiently remove hydrogen released into the containment, passive auto-catalytic recombiners (PARs) located close to the containment wall have to establish an internal upward directed chimney flow against this counter flow. In cooperation between RWTH Aachen and the Research Center Jülich, the effect of a downward directed flow on the PAR start-up has been investigated in the REKO-4 test facility at Jülich. The test series includes experiments with identical boundary conditions performed under counter flow conditions as well as in quiescent atmosphere as reference case. Under counter flow conditions, an earlier local start-up of the catalytic reaction on the upper edge of the catalyst sheets was observed. However, the establishment of full PAR operation required more time compared to the reference case. This delay is attributed to a partial inflow of the counter flow into the PAR outlet which interferes with the establishing of a chimney flow promoted by the exothermal catalytic reaction. Once a developed chimney flow inside the PAR is established, no negative effect on the PAR performance could be observed. As expected, the counter flow mixes immediately with the PAR outlet flow dissolving the characteristic plume of hot gases at the PAR outlet.

  8. Process for electroless deposition of metals on zirconium materials

    Science.gov (United States)

    Donaghy, Robert E.

    1978-01-01

    A process for the electroless deposition of a metal layer on an article comprised of zirconium or a zirconium alloy is disclosed. The article is activated in an aged aqueous solution comprising from about 10 to about 20 grams per liter ammonium bifluoride and from about 0.75 to about 2 grams per liter of sulfuric acid. The solution is aged by immersion of pickled zirconium in the solution for at least about 10 minutes. The loosely adhering film formed on the article in the activating step is removed and the article is contacted with an electroless plating solution containing the metal to be deposited on the article upon sufficient contact with the article.

  9. A New Activation Method for Electroless Metal Plating:Palladium Laden via Bonding with Self—Assembly Monolayers

    Institute of Scientific and Technical Information of China (English)

    LiNaXU; JianHuiLIAO; 等

    2002-01-01

    A new activation method has been developed for electroless copper plating on silicon wafer based on palladium chemisorption on SAMs of APTS without SnCl2 sensitization and roughening condition.A closely packed electroless copper film with strong adhesion is successfully formed by AFM observation.XPS study indicates that palladium chemisorption occurred via palladium chloride bonding to the pendant amino group of the SAMs.

  10. Modeling the electroless nickel deposition on aluminum nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Beygi, H., E-mail: hossein.beygi@stu-mail.um.ac.ir [Department of Materials Science and Engineering, Engineering Faculty, Ferdowsi University of Mashhad, Mashhad (Iran, Islamic Republic of); Vafaeenezhad, H.; Sajjadi, S.A. [Department of Materials Science and Engineering, Engineering Faculty, Ferdowsi University of Mashhad, Mashhad (Iran, Islamic Republic of)

    2012-07-15

    In this study, Ni coated aluminum nanoparticles were fabricated by electroless nickel deposition. Effect of two groups of parameters on the process plating rate were investigated: bath composition (main salt, reducing agent and complexing agent concentration) and process parameters (pH, plating time and bath temperature). Simulation of the process was performed using artificial neural network (ANN) media. Based on the presented model it is possible to design a high efficiency electroless bath, while minimum received materials are used and maximum plating rate is obtained. According to the model's results, 0.07 mol/l NiSO{sub 4}{center_dot}2H{sub 2}O, 0.245 mol/l NaH{sub 2}PO{sub 2}{center_dot}H{sub 2}O and 0.098 mol/l Na{sub 3}C{sub 6}H{sub 5}O{sub 7}{center_dot}H{sub 2}O were chosen as the optimum electroless bath composition. The optimum bath parameters also were selected as pH of 9.5, temperature of 80 Degree-Sign C and 30 min of plating. At such condition, the most efficient Ni deposition, with maximum plating rate of 45%, was acquired on the surface of aluminum particles. These samples were characterized by scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The results showed that a low phosphorus and nanocrystalline Ni layer, with about 30 nm thickness, has been coated on the aluminum nanoparticles.

  11. Kinetics of electroless Ni-Cu-P deposits on silicon in a basic hypophosphite-type bath

    Institute of Scientific and Technical Information of China (English)

    Wei-Long Liu; Shu-Huei Hsieh; Wen-Jauh Chen

    2009-01-01

    Eleetroless Ni-Cu-P deposits were deposited on the Si substrate in a basic hypophosphite-type plating bath.The effects ofpH value and the metal source composition, Ni and Cu, in the plating bath on the kinetics of the Ni-Cu-P deposition were studied.The electroless Ni-Cu-P deposits were characterized by a scanning electron microscope, a transmission electron microscope, an en-ergy dispersive X-ray spectroscope, and an X-ray diffractometer.The results showed that the pH value of the plating bath had no ob- vious effect on the morphology and composition of electroless Ni-Cu-P deposits.However, the composition of the metal source, Ni and Cu, in the plating bath had great effect on the kinetics of electroless Ni-Cu-P deposition.

  12. Atomic force microscopy and x-ray photoelectron spectroscopy investigations of the morphology and chemistry of a PdCl2/SnCl2 electroless plating catalysis system adsorbed onto shape memory alloy particles

    Science.gov (United States)

    Silvain, J. F.; Fouassier, O.; Lescaux, S.

    2004-11-01

    A study of the different stages of the electroless deposition of copper on micronic NiTi shape memory alloy particles activated by one-step and two-step methods has been conducted from both a chemical and a morphological point of view. The combination of x-ray photoelectron spectroscopy (XPS) measurements and atomic force microscopy (AFM) imaging has allowed detection of the distribution of the formed compounds and depth quantification and estimation of the surface topographic parameters. For the two-step method, at the sensitization of the early stages, it is observed by AFM that Sn is absorbed in form of clusters that tend to completely cover the surface and form a continuous film. XPS analysis have shown that Sn and Pd are first absorbed in form of oxide (SnO2 and PdO) and hydroxide [Sn(OH)4]. After the entire sensitization step, the NiTi substrate is covered with Sn-based compounds. After the sensitization and the activation steps the powder roughness increases. Behavior of the Sn and Pd growth for the one-step method does not follow the behavior found for the two-step method. Indeed, XPS analysis shows a three-dimensional (3D) growth of Pd clusters on top of a mixture of metallic tin, oxide (SnO) and hydroxide [Sn(OH)2]. These Pd clusters are covered with a thin layer of Pd-oxide contamination induced by the electroless process. The mean roughness for the one-step and two-step processes are equivalent. After copper deposition, the decrease of mean roughness is attributed to a filling of surface valleys, observed after the Sn-Pd coating step.

  13. The Linear Regression Method for Improving Magnetic Parameter of the Electroless CoFeB Films

    Institute of Scientific and Technical Information of China (English)

    LIU Changhui; HE Huahui; SHEN Xiang; LI Haihua

    2008-01-01

    The kinetics equation of deposition rate was implemented to help explain some of the mechanisms responsible for structures observed during the deposition of CoFeB films on poly-ester plastic.The plating rate of electroless CoFeB films is a function of concentration of sodium tetrahydroborate, pH of the plating bath, plating temperature and the metallic ratio. The estimated regression coefficient, confidence interval, residual error and confidence interval were confirmed by computer program. The optimal composition of the plating bath was obtained and the dynamic electromagnetic parameters of films were measured in the 2-10 GHz range. At 2 GHz, the permeability, magnetic loss of the electroless CoFeB films were 304,76.6 respectively as the concentration of reducer is 1 g·L-1.

  14. PLATE

    DEFF Research Database (Denmark)

    Kling, Joyce; Hjulmand, Lise-Lotte

    2008-01-01

    Project in Language Assessment for Teaching in English (PLATE) language professionals from CBS’s Language Center observe teachers and provide feedback using evaluation criteria from the Common European Framework for Reference (CEFR) supplemented by some additional criteria which take the LSP nature of......Copenhagen Business School (CBS) finds itself needing to address the issue of English-medium instruction for its increasing number of foreign exchange and full degree students. With internationalisation as a main pillar of the institution’s agenda, there are concerns whether the teaching faculty......’s level of English is sufficient for the increasing number of courses offered in English each semester. This paper addresses these concerns and describes a pilot project initiated in 2003 at CBS to gauge the overall English language proficiency of those teaching content courses in English. Through the...

  15. Study of electroless Ni-W-P alloy coating on martensitic stainless steel

    Science.gov (United States)

    Nikitasari, Arini; Mabruri, Efendi

    2016-04-01

    Electroless nickel phospor (Ni-P) is widely used in many industries due to their corrosion and wear resistance, coating uniformity, and ability to coat non-conductive surfaces. The unique properties of tungsten such as high hardness, higher melting point, lower coefficient of linear thermal expansion, and high tensile strength have created a lot of interest in developing ternary Ni-W-P alloys. This article presents the study of electroless Ni-W-P alloys coating using acid or alkaline bath on martensitic stainless steel. Nickel sulfate and sodium tungstate were used as nickel and tungsten sources, respectively, and sodium hypophosphite was used as a reducing agent. Acid or alkaline bath refer to bath pH condition was adjusted by adding sulfuric acid. Martensitic stainless steel was immersed in Ni-W-P bath for 15, 30, and 60 minutes. The substrate of martensitic stainless steel was subjected to pre-treatment (polishing and cleaning) and activation prior to electroless plating. The plating characteristics were investigated for concentration ratio of nickel and hypophosphite (1:3), sodium tungstate concentration 0,1 M, immersion time (15 min, 30 min, 60 min), and bath condition (acid, alkaline). The electroless Ni-W-P plating was heat treated at 400°C for 1 hour. Deposits were characterized using scanning electron microscope (SEM) and corrosion measurement system (CMS).

  16. TEMPERATURE DEPENDENCE OF ELECTROLESS Ni–P DEPOSITION ON POLYESTER FABRIC

    OpenAIRE

    R. H. GUO; Jiang, S Q; C. W. M. Yuen; M. C. F. NG

    2008-01-01

    The effects of plating temperature on the plating rate, P content, surface morphology, and electrical resistance of the electroless Ni–P deposits were studied. The results showed that the deposition rate of the Ni–P deposit and P content of the Ni–P layer increased with the rise of temperature of the plating bath. Scanning electron microscopy of the Ni–P deposits showed a nodule structure. The Ni–P plating layers had an amorphous structure and surface resistance of the layer decreased with th...

  17. Electroless Ni-P Deposition on Magnesium Alloy from a Sulfate Bath

    Institute of Scientific and Technical Information of China (English)

    LI Guangyu; NIU Liyuan; JIANG Qing; JIANG Zhonghao; LIAN Jianshe

    2008-01-01

    A technology for electroless Ni-P deposition on AZ91D from a low cost plating bath containing sulfate nickel was proposed.The seal pretreatment was employed before the electroless Ni-P deposition for the sake of occluding the micro holes of the cast magnesium alloy and interdicting the bubble formation in the Ni-P coating during plating process.And pickling pretreatment can provide a better adhesion between the Ni-P deposition and AZ91D substrate.The deposition speed of the Ni-P coating is 29 um/h.The technology is employed to AZ91D magnesium alloy automobile parts and can provide high hardness and high wear-resistant.The weight losses of Ni-P plated and heat-treated Ni-P plated magnesium alloy specimen are only about I/6 and 1/10 that of bare magnesium alloy specimen after l0 min abrasion wear,respectively.The hardness of the electroless Ni-P plated brake pedal support brackets is 674.1 VHN and 935.7 VHN after 2 hours heat treatments at 180 C.The adhesion of Ni-P coatings on magnesium alloy substrates meets the demands of ISO Standards 2819.The technology is environment friendly and cannot cause hazard to environment because of absence of chromate in the whole process.

  18. The Effect of pH on the Electroless Ni Plating on the SiC Powder%pH值对碳化硅粉体表面镀镍的影响

    Institute of Scientific and Technical Information of China (English)

    姚怀; 朱广林

    2013-01-01

    The surface of SiC was plating mental of Ni, and the effect of pH of plating bath on plating speed, phase composition and microstructure was investigated. The results show that the SiC powders have no plating mental of Ni and no reaction can occur when the pH below 8.5. When the pH value is between 10 and 11, the weight gain of powders close to the theoretical value, the Ni peaks in X-ray diffraction patterns of powders is relatively strong and the substrate is covered of Ni plating completely. When the pH value is above 11, the gas production is becoming more pronounced and the reaction speed accelerates significantly with the increased of the pH value, the time of the plating bath changed from dark blue to colorless is obviously shortened. The double-plating is be carry out when the pH value is between 10 and 11, the plating becomes more thickness and has a uneven surfaces, the sizes of Ni particle are not uniform.%对碳化硅表面进行化学镀镍,研究了镀液的pH值对镀速、镀层组织及形貌的影响.结果表明:镀液pH值低于8.5时,无反应发生,粉体未镀上镍;pH值为10 ~11时,粉体的增重接近理论值,XRD图谱中的镍衍射峰较强,镀层完全覆盖基体;pH值高于11时,随着pH值的升高,气体生成越发明显,反应速度明显加快,镀液由深蓝色变为无色的时间明显缩短.在pH值10~11范围内对粉体进行二次化学镀,镀层厚度明显增大且显得凸凹不平,镀层中的镍颗粒大小不均匀.

  19. Magnetic Properties and Kinetics Parameters of Electroless Magnetic Loss CoFeB Films

    Institute of Scientific and Technical Information of China (English)

    LIU Chang-hui; HE Hua-hui; SHEN Xiang; LI Hai-hua

    2008-01-01

    Electroless CoFeB films with good soft magnetic properties were fabricated on polyester plastic substrate from sodium tartarate as a complexing agent. The plating rate of electroless CoFeB films is a function of concentration of sodium tetrahydroborate, pH of the plating bath, plating temperature and the metallic ratio. The estimated regression coefficient b0-b3 confidence interval, residual error r and confidence interval rint were confirmed by a computer program. The optimal composition of the plating bath was obtained and the dynamic electromagnetic parameters of films were measured in the 2-10 GHz range. At 2 GHz, the μ′, μ″ of the electroless CoFeB films were 304 and 76.6, respectively, as the concentration of reducer is 1 g/L. Magnetic hysteresis loop of the deposited CoFeB films show a remanence close to the saturation magnetization and coercivity of about 55.7-127.4 A/m. The loops along the hard axis display low anisotropic field Hk of 2 388-3 582 A/m.

  20. Preparation of Crosslinked Poly(styrene-methyl methacrylate) Microspheres and Magnetization Processing on Their Surfaces by Electroless Nickel Plating%聚苯乙烯-甲基丙烯酸甲酯交联微球的制备及表面化学镀镍磁性化处理

    Institute of Scientific and Technical Information of China (English)

    华丽; 朱世明; 张蕾; 董桃杏

    2011-01-01

    Crosslinked poly(styrene-methyl methacrylate) microspheres(P(St-MMA))were prepared by dispersion polymerization of styrene(St) and methyl methacrylate(MMA) in mixed solvent of ethanol and deionized water,using azodiisobutyronitrile(AIBN) as the initiator,polyvinylpyrrolidone(PVP) as stabilizer and trimethylolpropane trimethylacrylate(TMPTMA) as crosslinking agent.Microspheres with 3—4 μm in diameter with narrow particle size distribution were achieved by feeding the second monomer under starved condition.Then electroless nickel plating on microspheres were carried out and magnetic microspheres were synthesized suceessfully.Morphology and content of microspheres before and after plating were analyzed by SEM technology coupled with EDAX analysis.The optimal plating condition was: using process II with gel palladium solution as activation step,acid plating solution B with pH of 6.0,adding rate of plating solution of 0.5 mL/min.Under the optimal condition,perfect nickel-plating layer was obtained,which were strongly adhere to macromolecule microspheres without break-off and crazed phenomena during ultrasound and centrifugal process.The mass density of plated Ni-P(St-MMA) microsphere was 2.3—2.5 g/cm3.The microspheres are as light as macromolecule material and show excellent nickel magnetism,which provides a novel adsorptive or catalytic degradation material for pollution control of industrial wastewater.%采用苯乙烯(St)、甲基丙烯酸甲酯(MMA)、偶氮二异丁腈(AIBN)为引发剂,聚乙烯基吡咯烷酮(PVP-K30)为分散剂,无水乙醇和去离子水混合溶液为分散介质,三羟甲基丙烷三甲基丙烯酸酯(TMPTMA)为交联剂,以饥饿态加料方式加入第2种单体,用单分散聚合法制备了粒径分布窄、平均粒径为3~4μm的聚苯乙烯-甲基丙烯酸甲酯(P(St-MMA))交联微球,并对微球表面进行化学镀镍,成功获得了磁性微球。采用扫

  1. Novel technology of electroless Ni-W-P on plastics and its interface behavior

    Institute of Scientific and Technical Information of China (English)

    WANG Tian-xu; HU Yong-jun; MENG Ji-long

    2004-01-01

    The electroless Ni-W-P coatings on polyoxymethylene(POM) were prepared. The POM was pretreated by hot spraying Al powder on it. Before the electroless Ni-W-P deposition, the POM with Al coating was flash plated in alkaline bath. The mechanism of Ni-W-P deposition was studied and the technology was optimized. The XRD analysis shows that the "as-deposited" Ni-W-P plating has mixed crystalline structure. The hardness value of deposits is more than HV700. The abrasion resistance of deposits is six times more than that of POM. Bending test was used to determine the cohesion between the deposits and the substrates. SEM was used to study the behavior of surface abrasion and interface bonding condition. The reason for the excellent cohesion was interpreted.

  2. Ductile electroless Ni-P coating onto flexible printed circuit board

    Science.gov (United States)

    Wang, Wenchang; Zhang, Weiwei; Wang, Yurong; Mitsuzak, Naotoshi; Chen, Zhidong

    2016-03-01

    In this study, a ductile electroless Ni-P coating on the flexible printed circuit board (FPCB) was prepared in an acidic nickel plating bath. The addition of dipropylamine (DPA) in electroless plating not only improves the ductility of the Ni-P coating, but also enhances the corrosion resistance. The further analysis reveals that the ductility improvement and enhancement of corrosion resistance for the Ni-P coating may be due to the fact that the addition of DPA significantly refines the volume of columnar nodule and reduce the porosity, thus leading to the released internal stress. In addition, it was found that the nodule within the Ni-P coating grew into a columnar structure, which may be also contribute to the improvement of ductility.

  3. Metal patterning on silicon surface by site-selective electroless deposition through colloidal crystal templating.

    Science.gov (United States)

    Asoh, Hidetaka; Sakamoto, Seiji; Ono, Sachiko

    2007-12-15

    Site-selective Cu deposition on a Si substrate was achieved by a combination of colloidal crystal templating, hydrophobic treatment, and electroless plating. Uniformly sized nano/microstructures were produced on the substrate using a monolayer coating of colloidal spheres instead of a conventional resist. The Cu patterns obtained were of two different types: networklike honeycomb and isolated-island patterns with a minimum period of 200 nm. Each ordered pattern with the desired intervals was composed of clusters of Cu nanoparticles with a size range of 50-100 nm. By the present method, it is possible to control the periodicity of metal arrays by changing the diameter of the colloidal spheres used as an initial mask and to adjust the shape of the metal patterns by changing the mask structure for electroless plating. PMID:17915242

  4. Effect of Metalloid Elements on Composition, Structure and Cor-rosion of Electroless Plated Permalloy%类金属元素对化学沉积坡莫合金成分、结构及耐蚀性的影响

    Institute of Scientific and Technical Information of China (English)

    王玲玲; 赵立华; 黄桂芳; 袁晓俭; 张邦维; 张建勇

    2001-01-01

    用化学沉积法在铜和碳钢基体上施镀Ni-Fe-P和Ni-Fe-P-B坡莫合金镀层。X射线衍射测定结果及镀层的腐蚀试验结果表明,镀液中还原剂的浓度、金属盐比及pH值,对镀层成分、晶体结构及耐蚀性能有直接影响。使镀层具有非晶态结构和较强的钝化趋势,是获得耐蚀性良好的镀层的主要条件。适当提高Fe含量,在镀液中加入B元素,有利于提高镀层的耐蚀性。%Cailiao Baohu 2001, 34(1),12~14(Ch). The metalloid elements P, B had an obvious effects on the com-position, structure and corrosion of the electroless plated Permalloy. TheXRF, XRD and electrochemical experimental results showed that thedeposits with various compositions, amorphous or crystalline structurescould be obtained by controlling the pH value, NaH2PO2 and KBH4concentration, and salt ratio FeSO4/(FeSO4+NiSO4). The maximumiron content (38 atom percent) of the coating was obtained at 28 g/LNaH2P04, 0. 5 metallic salt ratio for Ni-Fe-P alloy and 0.4 g/L KBH4for Ni-Fe-P-B alloy deposits. The addition of trace KBH4 could improvethe corrosion resistance of Ni-Fe-P alloy coating in alkaline solution.

  5. Métallisation Electroless des Polymères Induite par des Ligands

    OpenAIRE

    Garcia, Alexandre

    2011-01-01

    The main goal of this research project was to answer to an industrial issue: To develop a "green" process for the electroless plating of polymers without chromic acid (CrVI) etching. During this work, an alternative process based on an innovative surface coating technology (Graftfast® technology) has been developed. This technique which is working in aqueous solution and at room temperature allows to chemically graft vinylic polymers on various types of substrates. Based on this method, a pol...

  6. Towards an electroless deposition of gold on metallic substrates using ionic liquids as electrolytes

    OpenAIRE

    Sá, A. I. Correia de; Quaresma, S.; Eugénio, S.; Rangel, C. M.; Vilar, Rui

    2010-01-01

    Recent research has suggested a number of applications for gold in fuel cells and related hydrogen fuel processing, which include coatings for light weight corrosion resistance bipolar plates and the incorporation of gold as catalyst to provide improvements in electrode conductivity, among others. This paper reports on the electroless deposition of gold on copper substrates from a HAuCl4.3H2O solution in 1-butyl-1-methylpyrrolidinium dicyanamide (BMP-DCA), in normal atmospheric conditions. Th...

  7. Preparation and in-vitro Antibacterial Evaluation of Electroless Silver Coated Polymers

    OpenAIRE

    Fazeli, Mohammad Reza; Hosseini, Vahid; Shamsa, Fazel; Jamalifar, Hossein

    2010-01-01

    Long-term use of indwelling medical catheters has often been hindered by catheter-associated nosocomial infections. In this study the effectiveness of silver coating of polystyrene and polyethylene polymers was investigated. Polymer pieces of 2 cm2 each were coated with a thin layer of silver using electroless plating technique. Silver-coated polymers were challenged with cultures of four different microorganisms known for their involvement in nosocomial infections in both solid and broth med...

  8. Effects of Two Purification Pretreatments on Electroless Copper Coating over Single-Walled Carbon Nanotubes

    OpenAIRE

    Zhong Zheng; Lianjie Li; Shijie Dong; Anchun Xiao; Shixuan Sun; Sinian Li

    2014-01-01

    To achieve the reinforcement of copper matrix composite by single-walled carbon nanotubes, a three-step-refluxing purification of carbon nanotubes sample with HNO3-NaOH-HCl was proposed and demonstrated. A previously reported purification process using an electromagnetic stirring with H2O2/HCl mixture was also repeated. Then, the purified carbon nanotubes were coated with copper by the same electroless plating process. At the end, the effects of the method on carbon nanotubes themselves and o...

  9. Evolution of microstructure and electrical conductivity of electroless copper deposits on a glass substrate

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Xiaoyun; Hutt, David A., E-mail: D.A.Hutt@lboro.ac.uk; Conway, Paul P.

    2012-07-31

    This paper describes the evolution of the microstructure and conductivity of electroless copper deposition on a glass substrate for applications in electronics manufacture. The glass was activated using a (3-aminopropyl)trimethoxysilane pre-treatment followed by a Pd/Sn catalyst. Surface morphology of the deposited copper films was characterized using a dual beam focused ion beam field emission scanning electron microscope, and together with atomic force microscopy, showed clearly that the roughness and grain size tended to increase with the plating time. Film thickness measurements showed a high initial deposition rate, which slowed to a constant level as the thickness increased above 100 nm. This corresponded with the resistivity of the films which decreased rapidly as the thickness increased from 20 to 100 nm, but then remained largely stable at a level approximately twice that of bulk copper. - Highlights: Black-Right-Pointing-Pointer Morphology of electroless Cu on glass characterized as a function of plating time. Black-Right-Pointing-Pointer The deposition rate of electroless Cu varied with deposition time. Black-Right-Pointing-Pointer The roughness and grain size of the Cu deposits increased with the plating time. Black-Right-Pointing-Pointer The resistivity of Cu films was measured and related to changes in microstructure.

  10. Direct Ni Electroless Metallization of Poly(etherimide) without Using Palladium as a Catalyst

    Institute of Scientific and Technical Information of China (English)

    MarleneCharbonnier; MauriceRomand; YvesGoepfert

    2004-01-01

    Nickel or copper electroless metallization of polymers needs the grafting of a catalyst (palladium in the Pd(0) oxidation state) on the substrate surface to be coated. Our previous works on this topic [1-5] have allowed to develop a simple, tin-free method to attach Pd(+2) species from a palladium chloride (PdCl2) solution on any insulating surface and subsequently to reduce them, in the wet way, into the Pd(0) oxidation state. This Pd(0) state of the catalyst allows an instantaneous initiation of the Ni or Cu deposit by immersion in a plating bath. As palladium is an expensive chemical, it appears interesting to replace it by Ni(0) or Cu(0) species which are catalysts of their own ion reduction. Concerning the direct Ni electroless plating, the polymer surface (PI) was made catalytic for the electroless process by deposition (spincoating or dipping) of an ultra-thin film of an organic nickel salt in an alcoholic solution. The chemical reduction of this salt, checked by XPS, was performed by chemical or photochemical ways and by plasma. Under these conditions, the initiation, by autocatalysis, of the Ni film deposition in an industrial plating bath was immediate i.e. without any initiation time. The film obtained was homogeneous, dense, bright, well-adhering up to thicknesses reaching 3μm.

  11. Direct Ni Electroless Metallization of Poly(etherimide) without Using Palladium as a Catalyst

    Institute of Scientific and Technical Information of China (English)

    Mariène Charbonnier; Maurice Romand; Yves Goepfert

    2004-01-01

    Nickel or copper electroless metallization of polymers needs the grafting of a catalyst (palladium in the Pd(0) oxidation state) on the substrate surface to be coated. Our previous works on this topic [1-5] have allowed to develop a simple, tin-free method to attach Pd(+2) species from a palladium chloride (PdCl2) solution on any insulating surface and subsequently to reduce them, in the wet way, into the Pd(0) oxidation state. This Pd(0) state of the catalyst allows an instantaneous initiation of the Ni or Cu deposit by immersion in a plating bath. As palladium is an expensive chemical, it appears interesting to replace it by Ni(0) or Cu(0) species which are catalysts of their own ion reduction. Concerning the direct Ni electroless plating, the polymer surface (PI) was made catalytic for the electroless process by deposition (spincoating or dipping) of an ultra-thin film of an organic nickel salt in an alcoholic solution. The chemical reduction of this salt, checked by XPS, was performed by chemical or photochemical ways and by plasma. Under these conditions, the initiation, by autocatalysis, of the Ni film deposition in an industrial plating bath was immediate i.e. without any initiation time. The film obtained was homogeneous, dense, bright, well-adhering up to thicknesses reaching 3 μm.

  12. Failure mechanism of ZrO2-8%Y2O3 thermal barrier coatings on aluminum alloy with electroless plating interlayer%铝合金基体上含化学镀过渡层的二氧化锆热障涂层失效机制

    Institute of Scientific and Technical Information of China (English)

    陆冠雄; 郝利军; 刘彻; 叶福兴

    2014-01-01

    To relieve the thermal mismatch stress between coatings and substrate, Ni-P and Ni-Cu-P electroless platings were fabricated onto 2A70 aluminum as interlayers. Subsequently, the specimen with plating was covered by CoNiCrAlY bond coat and ZrO2-8%Y2O3(8YSZ) top coat (mass fraction), then a novel thermal barrier coating (TBC) was produced. The thermal shock resistance of TBCs was evaluated by heat cycle test. The results indicate that the lifetimes of TBC with Ni-P interlayer and Ni-Cu-P interlayer are about 1000 cycles and 500 cycles, respectively. The interdiffusion of Ni and Al results in the formation of diffusion layers and island particles at the interface between interlayers and substrate. The connection between particles and diffusion layers improves the adhesion of coatings with substrate, while isolate particles are harmful to the lifetime of coatings due to their poor deformation ability under alternative stress. Crack initiation happens at the interfaces between particles and substrate, which leads to coatings spallation.%为了缓解涂层和基体之间的热失配应力,采用化学镀方法在2A70铝合金表面上制备Ni-P和Ni-Cu-P过渡层;然后在镀层表面依次制备CoNiCrAlY粘结层和ZrO2-8%Y2O3(8YSZ)陶瓷层(质量分数),获得复合热障涂层;并采用热循环方法评定该涂层体系的抗热震性能。结果表明,采用Ni-P镀层和Ni-Cu-P镀层作为过渡层的试样的热震寿命分别约为1000次和500次;Ni和Al元素的互扩散使过渡层与基体界面区域形成了扩散层和岛状颗粒,一些颗粒与扩散层连通后提高了涂层与基体的结合强度,但孤立的颗粒由于变形能力差,对涂层的寿命有不利影响;在交变应力下颗粒与基体界面处会形成裂纹,并最终导致涂层剥离。

  13. A novel electroless silver depositing method for magnesium alloys

    Institute of Scientific and Technical Information of China (English)

    ZHAO Hui; CUI Jian-zhong

    2006-01-01

    Depositing silver on magnesium alloy by both electroless plating and organic coatings was studied. The organic coating was made by immersing samples in organosilicon heat-resisting varnish. In this method the organic coating acts as interlayer between the substrate and silver film. When the reaction starts, silver deposits directly on the interlayer. X-ray diffraction and SEM analysis were used to determine the composition and morphology of the interlayer and silver film. The potentiodynamic polarization curves for corrosion studies of coated magnesium alloys were performed in a corrosive environment of 3.5% NaCl(mass fraction) at neutral pH (6.9). The results indicate that compared with the substrate, the corrosion resistance of coated magnesium alloys increases greatly. Moreover, the method proposed in this work is environmentally friendly, non-toxic chemicals were used. In addition, it provides a new concept for the corrosion inhibition of magnesium alloys.

  14. Nanocrystalline Pd alloy films coated by electroless deposition.

    Science.gov (United States)

    Strukov, G V; Strukova, G K; Batov, I E; Sakharov, M K; Kudrenko, E A; Mazilkin, A A

    2011-10-01

    The structures of palladium and palladium alloys thin films deposited from organic electrolytes onto metallic substrates by electroless plating method have been investigated. The coatings are dense, pore-free 0.005-1 microm thick films with high adhesive strength to the substrate surface. EDX, XRD, SEM and TEM methods were used to determine the composition and structure of alloy coatings of the following binary systems: Pd-Au, Pd-Ag, Pd-Ni, Pd-Pb, and ternary system Pd-Au-Ni. The coatings of Pd-Au, Pd-Ag and Pd-Ni have a solid solution structure, whereas Pd-Pb is intermetallic compound. It has been found that the deposited films consist of nanocrystalline grains with sizes in the range of 11-35 nm. Scanning and transmission electron microscopy investigations reveal the existence of clusters formed by nanocrystalline grains. The origin for the formation of nanocrystalline structures of coating films is discussed. PMID:22400291

  15. Study of the Electroless Deposition of Ni for Betavoltaic Battery Using PN Junction without Seed Layer

    OpenAIRE

    Jin Joo Kim; Young Rang Uhm; Byoung Gun Choi; Kwang Jae Son

    2015-01-01

    The method and conditions of Ni plating were optimized to maximize the output of a betavoltaic battery using radioactive 63Ni. The difference of the short circuit currents between the pre- and postdeposition of 63Ni on the PN junction was 90 nA at the I-V characteristics. It is suspected that the beta rays emitted from 63Ni did not deeply penetrate into the PN junction due to a Ni seed layer with a thickness of 500 Å. To increase the penetration of the beta rays, electroless Ni plating was ca...

  16. Fabrication of Ni-B alloy coated vapor-grown carbon nanofibers by electroless deposition

    OpenAIRE

    Arai, Susumu; Imoto, Yuzo; Suzuki, Yosuke; Endo, Morinobu

    2011-01-01

    Ni-B alloy coated vapor-grown carbon nanofibers (VGCNFs) were fabricated by electroless deposition and their microstructures were investigated. The effects of heat treatment on the coated VGCNFs were also studied. VGCNFs could be coated with a homogeneous Ni-B alloy film using a plating bath containing dimethylaminoborane (DMAB) as a reducing agent. The boron content of the Ni-B alloy film could be varied from 14 to 24 atom% B by varying the DMAB concentration of the plating bath. The VGCNFs ...

  17. EFFECT OF ANNEALING TEMPERATURE ON HARDNESS AND WEAR RESISTANCE OF ELECTROLESS Ni–B–Mo COATINGS

    OpenAIRE

    IHSAN GÖKHAN SERIN; ALI GÖKSENLI

    2015-01-01

    Formation of nickel–boron–molybdenum (Ni–B–Mo) coating on steel by electroless plating and evaluation of their morphology, hardness and tribological properties post heat treatment at different temperatures for 1 h is investigated. The 25 μm thick coating is uniform and adhesion between the substrate and coating is good. Ni–B–Mo coating was amorphous-like structure in their as-plated condition and by 400°C heat-treated coating, nickel fully crystallized and nickel borides and molybdenum carbid...

  18. Study on Electrochemical Characteristics of Electroless Co-Ni-B Alloy with Cerium

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The effects of rare earth element cerium on composition and electrochemical characteristics of electroless Co-Ni-B alloy were studied in this paper. The alloy component was analyzed using Inductively Coupled Plasma (ICP). The plating rate is was determined by electronic balance. The cathode polarization curves and cyclic voltammogram during the electroless deposition were tested by LK998Ⅱmodel electrochemical analytical system. The results show that rare earth element Ce can co-deposit with cobalt-based alloy, and with mass increase of Ce added in aqueous solution, the contents of Co, Ni, Ce in alloy increase and the content of B decreases. Ce can increase deposition rate of alloy in some range. The rare earth makes deposition potential move to positive direction and makes polarizability decrease.

  19. Preparation and Tribological Properties of Ni-P Electroless Composite Coating Containing Potassium Titanate Whisker

    Institute of Scientific and Technical Information of China (English)

    Yaxu JIN; Lin HUA

    2007-01-01

    Nickel-phosphorus (Ni-P) composite coatings containing potassium titanate (K2Ti6O13) whiskers (PTWs) were prepared by electroless plating. The surface morphology and component of coatings were investigated by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX), respectively before and after wear test. The tribological performance was evaluated using a pin-on-disk wear tester under dry conditions. It is found that the Ni-P-PTWs composite coatings exhibit higher wear resistance than Ni-P and Ni-P-SiC electroless coatings. The favorable effects of PTWs on the tribological properties of the composite coatings are attributed to the super-strong mechanical properties and the specific tunneling structures of PTWs. The PTWs greatly reinforce the structure of the Ni-P-based composite coatings and thereby greatly reduce the adhesive and plough wear of Ni-P-PTWs composite coatings.

  20. 用于化学复合镀的Ni3.1B非晶态纳米合金粉体的制备%Preparation of Ni3.1B Amorphous Nano Alloy Particles for Electroless Composite Plating

    Institute of Scientific and Technical Information of China (English)

    王钰蓉; 王文昌; 石建华; 光崎尚利; 陈智栋

    2013-01-01

    Ni3.1B amorphous nano alloy particles used for electroless (Ni-P)-Ni3.1 B composite plating were prepared by chemical reducing method with borohydride(KBH4) as reducing agent.After investigted the effect of KBH4,thiourea and PVP concentration on the size of Ni3.1 B particle,the optimized preparation conditions were obtained as 0.02 mol/L NiCl2-6H2O,0.06 g/L KBH4,2 mg/L thiourea and 0.25 g/L PVP.By analyzing the dispersity and stability of Ni3.1 B particle in the Ni-P-B electrolyte,it was found that sodium alginate has a better coating effect to Ni3.1B particle.%利用化学还原法,以硼氢化钾为还原剂,制备了Ni3.1B非晶态纳米合金粉末,用于化学镀(Ni-P)-Ni3.1B合金镀层.通过对还原剂硼氢化钾、稳定剂硫脲和表面活性剂聚乙烯吡咯烷酮对Ni3.B纳米合金粉末的粒径的影响,确定化学还原法制备Ni3.1B的最佳条件为0.02 mol/L NiCl2 ·6H2O,0.06 g/L KBH4,2mg/L硫脲,0.25 g/L聚乙烯吡咯烷酮.通过对Ni3.1B粉体分散性和在化学镀Ni-P-B合金镀液中的稳定性的研究,发现海藻酸钠对Ni3.1B具有良好的包覆效果.

  1. Effect of SiC size on Ni-P-SiC coatings prepared by magnetic stirring-electroless plating method%SiC粒度对磁力搅拌-化学沉积Ni-P-SiC镀层的影响

    Institute of Scientific and Technical Information of China (English)

    王勇; 马春华; 楚殿庆

    2013-01-01

    用磁力搅拌-化学沉积方法在45钢表面制备Ni-P-SiC镀层,研究镀液中SiC颗粒粒度对镀层表面形貌、显微硬度及耐磨性能的影响.结果表明:随着SiC颗粒的粒度逐渐减小,镀层的平整度和致密性增加,SiC颗粒团聚现象越来越不明显;当SiC粒度为0.2μm,Ni-P-SiC镀层表面均匀分散着微小的SiC颗粒,镀层平整、致密,平均显微硬度为853.4HV;当SiC粒度为1,2μm,最大硬度差分别为25.8HV和40.5HV.随着磨损时间的增加,含有SiC粒度0.2 μm的Ni-P-SiC镀层的磨损量缓慢增加,而SiC粒度为2,1μm的Ni-P-SiC镀层的磨损量急剧增加.%Ni-P-SiC coatings were prepared by magnetic stirring-electroless plating method on 45 steel. The effect of SiC size on surface morphology, microhardness and binding force was investigated. The results show that the flatness and density of Ni-P-SiC coatings increase with SiC particle size decreasing. When the particle size of SiC is 0.2 μm, tiny SiC particles are uniformly distributed on the surface of coatings, the coatings are smooth and dense, and the average microhardness is 853.4HV. When the SiC particle size is 1 u,m and 2 μm, the microhardness change is bigger at different location of Ni-P-SiC coating, and the maximum is 25.8HV and 40.5HV, respectively. During the friction and wear test process, the wear rate of Ni-P-SiC coating with SiC size of 0.2 μm increases slowly. While the coatings with SiC size of 2 μm and 1 μm, the wear rate increases very sharply.

  2. The New Plating Process on Plastics

    Institute of Scientific and Technical Information of China (English)

    Makoto Imamura; Jun Okada; Kazuya Satoh

    2004-01-01

    This process does not use general electroless plating solution containing formaldehyde(carcinogen) and phosphate(the object of waste water regulation). Furthermore, we succeeded in developing a new electroless copper plating solution which is usable semi-permanently by using the special reducing agent. The electroless deposition forms a very thin conductive film on substrate. Therefore, it can prevent some appearance defects (e.g. pits, pin-holes, laminations and inclusions) that occur in the conventional ones. In addition, it is possible to eliminate electroplating of copper from the process by applying the exclusive nickel solution in electroplating. Therefore, the obtained metal parts can be recycled as high quality stainless steel. Given this copper electroplating-free process, 25μ m-thick nickel deposition at the stage of electroplating, at least, enables the metal layers to show properties as versatile as those of the conventional(its total thickness is 25μ m in the comparative conventional process).

  3. The New Plating Process on Plastics

    Institute of Scientific and Technical Information of China (English)

    MakotoImamura; JunOkada; KazuyaSatoh

    2004-01-01

    This process does not use general electroless plating solution containing formaldehyde(carcinogen) and phosphate(the object of waste water regulation). Furthermore. we succeeded in developing a new electroless copper plating solution which is usable semi-permanently by using the special reducing agent, The electroless deposition forms a very thin conductive film on substrate. Therefore, it can prevent some appearance defects (e.g. pits. pin-holes, laminations and inclusions) that occur in the conventional ones. In addition, it is possible to eliminate electroplating of copper from the process by applying the exclusive nickel solution in electroplating. Therefore, the obtained metal parts can be recycled as high quality stainless steel. Given this copper elecltoplating-free process, 25μ m-thick nickel deposition at the stage of electroplating, at least, enables the metal layers to show properties as versatile as those of the conventional(its total thickness is 25μm in the comparative conventional process).

  4. Experimental study on the formation and growth of electroless nickel-boron coatings from borohydride-reduced bath on mild steel

    Energy Technology Data Exchange (ETDEWEB)

    Vitry, Veronique, E-mail: veronique.vitry@umons.ac.be [Service de Metallurgie, Universite de Mons, Rue de l' Epargne 56, 7000 Mons (Belgium); Sens, Adeline [Service de Metallurgie, Universite de Mons, Rue de l' Epargne 56, 7000 Mons (Belgium); Kanta, Abdoul-Fatah [Service de Sciences des Materiaux, Universite de Mons, Rue de l' Epargne 56, 7000 Mons (Belgium); Delaunois, Fabienne [Service de Metallurgie, Universite de Mons, Rue de l' Epargne 56, 7000 Mons (Belgium)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Initiation mechanism of electroless Ni-B on St-37 steel has been identified. Black-Right-Pointing-Pointer Different phases of the plating process were observed and identified. Black-Right-Pointing-Pointer Influence of chemical heterogeneity on coating morphology was revealed. Black-Right-Pointing-Pointer Batch replenishment of the plating bath induces new germination phase. - Abstract: Quality and homogeneity of electroless nickel-boron coatings are very important for applications in corrosion and electronics and are completely dependent on the formation of the deposit. The growth and formation process of electroless nickel-boron was investigated by immersing mild steel (St-37) samples in an un-replenished bath for various periods of time (from 5 s to 1 h). The coatings obtained at the different stages of the process were then characterized: thickness was measured by SEM, morphology was observed, weight gain was recorded and top composition of the coatings was obtained from XPS. Three main phases were identified during the coating formation and links between plating time, instantaneous deposition rate, chemistry of last formed deposit and morphology were established. The mechanism for initial deposition on steel substrate for borohydride-reduced electroless nickel bath was also observed. Those results were confronted with chemistry evolution in the unreplenished plating bath during the process. This allowed getting insight about phenomena occurring in the plating bath and their influence on coating formation.

  5. Electroless ternary NiCeP coatings: Preparation and characterisation

    Energy Technology Data Exchange (ETDEWEB)

    Balaraju, J.N., E-mail: jnbalraj@nal.res.in [Surface Engineering Division, CSIR National Aerospace Laboratories, Post Bag No. 1779 Bangalore 560017, Karnataka (India); Chembath, Manju [Surface Engineering Division, CSIR National Aerospace Laboratories, Post Bag No. 1779 Bangalore 560017, Karnataka (India)

    2012-10-01

    Highlights: Black-Right-Pointing-Pointer Rare earth element (Ce) has been successfully codeposited in NiP matrix. Black-Right-Pointing-Pointer Surface analysis carried out by XPS showed that the Ce is present in +3 and +4 oxidation state. Black-Right-Pointing-Pointer Palladium stability test indicated that the Ce salts in electroless nickel bath has reduced the stability. Black-Right-Pointing-Pointer Cerium codeposition in NiP matrix has increased the microhardness both in as-plated and annealed conditions. Black-Right-Pointing-Pointer Higher thermal stability has been obtained by Ce incorporation. - Abstract: Electroless ternary NiCeP deposits were prepared from alkaline citrate bath containing nickel sulphate, cerium chloride and sodium hypophosphite. Concentration of rare earth cerium was varied from 1 to 2 g/L to obtain ternary deposits containing variable Ce and P contents. The influence of cerium on the deposit properties was analysed. The deposit exhibited a maximum cerium content of 6.2 {+-} 0.1 wt.% when the cerium chloride concentration was 2 g/L. The result of the Pd stability test showed that the stability of the bath was reduced due to Ce salt addition. The microhardness measurements made on both as-plated and heat treated samples exhibited a peak hardness of 1006 {+-} 11 VHN for cerium concentration of 1.5 g/L. The concept of kinetic strength analysis was proved to be applicable only for binary and not for ternary alloys due to multistep deposition mechanism with different kinetic energies. X-ray diffraction (XRD) patterns of as-plated and heat treated samples revealed peaks corresponding to Ni (1 1 1) and nickel phosphide (Ni{sub 3}P). Higher amount of Ce incorporation in NiP matrix increased the crystallisation temperature of the deposit which could be due to the suppression of nickel crystallisation prior to Ni{sub 3}P compound formation and thus increasing the activation energy for the formation of stable phases. Surface compositional analysis

  6. Electroless deposition of metal nanoparticle clusters: Effect of pattern distance

    KAUST Repository

    Gentile, Francesco

    2014-04-03

    Electroless plating is a deposition technique in which metal ions are reduced as atoms on specific patterned sites of a silicon surface to form metal nanoparticles (NPs) aggregates with the desired characteristics. Those NPs, in turn, can be used as constituents of surface enhanced Raman spectroscopy substrates, which are devices where the electromagnetic field and effects thereof are giantly amplified. Here, the electroless formation of nanostructures was studied as a function of the geometry of the substrate. High resolution, electron beam lithography techniques were used to obtain nonperiodic arrays of circular patterns, in which the spacing of patterns was varied over a significant range. In depositing silver atoms in those circuits, the authors found that the characteristics of the aggregates vary with the pattern distance. When the patterns are in close proximity, the interference of different groups of adjacent aggregates cannot be disregarded and the overall growth is reduced. Differently from this, when the patterns are sufficiently distant, the formation of metal clusters of NPs is independent on the spacing of the patterns. For the particular subset of parameters used here, this critical correlation distance is about three times the pattern diameter. These findings were explained within the framework of a diffusion limited aggregation model, which is a simulation method that can decipher the formation of nanoaggregates at an atomic level. In the discussion, the authors showed how this concept can be used to fabricate ordered arrays of silver nanospheres, where the size of those spheres may be regulated on varying the pattern distance, for applications in biosensing and single molecule detection.

  7. SURFACE METALLIZATION OF CENOSPHERES AND PRECIPITATORS BY ELECTROLESS PLATING

    Institute of Scientific and Technical Information of China (English)

    Chujiang Cai; Zhigang Shen; Mingzhu Wang; Shulin Ma; Yushan Xing

    2003-01-01

    This paper reports the use of a colloidal Pd0 catalysis system to metallize the surface of precipitators separated from coal fly-ash, and metals such as Cu, Ni etc. are deposited on the precipitators surface. Alternatively,according to the characteristic surface of cenospheres, an Ag coating catalysis system is adopted to first deposit Ag on the cenospheres surface, followed, if necessary, by the deposition of other metals such as Cu, Ni, etc. on the Ag coating to produce monolayer and multilayer metal-coated cenospheres. The surface characteristics and the morphologies of the metal coatings are examined in detail with scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS) techniques. It can be shown that the quality of metal coatings derived from the Ag coating catalysis system, is better than that of the colloidal Pd0 catalysis system.

  8. Laser Induced Selective Activation For Subsequent Autocatalytic Electroless Plating

    DEFF Research Database (Denmark)

    Zhang, Yang

    that chemical bonds exist. However, it is still not excluded that chemical bonding is part of the mechanism. The second hypothesis is that the laser track has a stronger attraction work to the activation solution. This is proved by a calculation using van Oss et al., theory based on contact angle measurement...... of an antenna. Two simple antenna shapes, planar dipole, and planar loop were studied, as well as a co-planar stripline. The antennas made by LISA exhibited impedance characteristics expected from the respective antenna shapes and comparable to antennas made by PCB technology....

  9. Effect of 3-Amino-5-mercapto-1,2,4-triazole on Electroless Nickel Deposition

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The effects of organic additive, 3-amino-5-mercapto-1,2,4-triazole (AMTA) on bath stability, deposition rate,reaction activation energy, and Ni-P coating composition in acidic electroless nickel plating were investigated.Polarization curve method and infrared reflection spectroscopy were used to analyze the mechanism of the effect of AMTA on electroless nickel deposition. It was observed that AMTA improved bath stability, decreased the deposition rate, and increased the reaction activation energy. It was also revealed that AMTA decreased the phosphorus content and increased the sulfur content in Ni-P coating. In addition, AMTA inhibited the anodic oxidation of hypophosphite and accelerated the cathodic reduction of Ni2+. Infrared reflection spectroscopy result indicates that AMTA was adsorbed on the surface of Ni-P and interacted with Ni2+ to form an AMTA-Ni2+ compound. On the basis of the results of this study,the mechanism of the effect of AMTA on electroless nickel deposition was deduced.

  10. Comparative study of electroless nickel film on different organic acids modified cuprammonium fabric (CF)

    Science.gov (United States)

    Zhao, Hang; Lu, Yinxiang

    2016-01-01

    Nickel films were grown on citric acid (CA), malic acid (MA) and oxalic acid (OA) modified cuprammonium fabric (CF) substrates via electroless nickel deposition. The nickel films were examined using scanning electron microscopy (SEM) and X-ray diffraction (XRD). Their individual deposition rate and electromagnetic interference (EMI) shielding effectiveness (SE) were also investigated to compare the properties of electroless nickel films. SEM images illustrated that the nickel film on MA modified CF substrate was smooth and uniform, and the density of nickel nuclei was much higher. Compared with that of CA modified CF, the coverage of nickel nuclei on OA and MA modified CF substrate was very limited and the nickel particles size was too big. XRD analysis showed that the nickel films deposited on the different modified CF substrates had a structure with Ni (1 1 1) preferred orientation. All the nickel coatings via different acid modification were firmly adhered to the CF substrates, as demonstrated by an ultrasonic washing test. The result of tensile test indicated that the electroless nickel plating on CF has ability to strengthen the CF substrate while causes limited effect on tensile elongation. Moreover, the nickel film deposited on MA modified CF substrate showed more predominant in EMI SE than that deposited on CA or OA modified CF.

  11. Selective Electroless Silver Deposition on Graphene Edges

    DEFF Research Database (Denmark)

    Durhuus, D.; Larsen, M. V.; Andryieuski, Andrei;

    2015-01-01

    We demonstrate a method of electroless selective silver deposition on graphene edges or between graphene islands without covering the surface of graphene. Modifications of the deposition recipe allow for decoration of graphene edges with silver nanoparticles or filling holes in damaged graphene...... on silica substrate and thus potentially restoring electric connectivity with minimal influence on the overall graphene electrical and optical properties. The presented technique could find applications in graphene based transparent conductors as well as selective edge functionalization and can be extended...

  12. 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...

  13. Study of Ni-catalyst for electroless Ni-P deposition on glass fiber

    International Nuclear Information System (INIS)

    Highlights: → Electroless nickel-phosphorus plating on the glass fiber surface. → We study the pretreatment including roughening and activation process. → The pretreatment parameters are optimized by orthogonal experiments. → Nickel-catalyst method is developed to activate the glass fiber surface. → Activated film containing nickel oxide particles will form catalytic centers. - Abstract: The glass fiber surface is metalized with electroless nickel-phosphorus deposition. The roughening and activation processes are optimized by the orthogonal experiments. A new nickel-catalyst method is developed to activate the glass fiber surface. When the activation is completed, a layer of continuous and dense film is formed on the substrate. The activated film contains a great deal of nickel oxide particles which can become the active sites after they are deoxidized in the electroless bath. In the activated film on the glass fiber, the content of Ni element is 41.01 wt.%, the content of O element is 45.64 wt.% and the content of P element is 13.35 wt.%. Scanning electron microscopy (SEM) shows that the Ni-P coatings obtained under the optimum pretreatment conditions are uniform, continuous and adhered to the glass fiber surface. Energy dispersive X-ray spectrometry (EDS) points out that the content of the nickel and the phosphorus in the deposits is 87.41 wt.% and 12.59 wt.%, respectively. X-ray photoelectron spectroscopy (XPS) analysis reveals that the O signal on electroless Ni-coated glass surface corresponds to oxygen in the glass substrate. X-ray diffraction pattern (XRD) indicates the Ni-P coatings are amorphous.

  14. Electroless deposition of SnOx-Sb nanocoating in ordered titania pores for enhancing electrical conductivity

    International Nuclear Information System (INIS)

    Sn and Sb were separately deposited into TiO2 nanotubes (TNTs) by electroless plating. A more conductive sub-stoichiometric TNT/SnOx-Sb layer was then prepared by controlled annealing. The electrical properties of the TNT/SnOx-Sb electrodes were characterized by cyclic voltammetry and electrochemical impedance spectroscopy. The presence of Sn contributes to the enhanced electrical conductivity. A small amount of Sn greatly improves the energy efficiency of TNT/SnOx-Sb electrodes for the degradation of nitrobenzene by enhancing the conductivity.

  15. Electroless nickel-phosphorus coating on poly (ether ether ketone)/carbon nanotubes composite

    Science.gov (United States)

    Zhai, Tong; Di, Lizhi; Yang, De'an

    2014-05-01

    In order to improve electromagnetic shielding property of poly (ether ether ketone)/carbon nanotubes composite, a nickel-phosphorus coating was covered on the composite by electroless plating. The morphologies of the substrates and the coatings were characterized by SEM. XPS was performed to analyze the surface composition and chemical states before and after chemical etching. The results showed that lots of microscopic holes appeared and evenly distributed on the surface, and the concentration of hydrophilic groups on the surface increased after the composite was etched. Thermal shock test showed that the adhesive strength between the coating and the composite was good.

  16. Investigation into conductivity of silver-coated cenosphere composites prepared by a modified electroless process

    Energy Technology Data Exchange (ETDEWEB)

    Cao Xiaoguo, E-mail: xgcao@gdut.edu.cn [School of Materials and Energy, Guangdong University of Technology, Guangzhou, Guangdong 510006 (China); Zhang Haiyan [School of Materials and Energy, Guangdong University of Technology, Guangzhou, Guangdong 510006 (China)

    2013-01-01

    Highlights: Black-Right-Pointing-Pointer In this paper we described a modified eletroless Ag-coating process on cenospheres. Black-Right-Pointing-Pointer The modified method makes the plating process more cost-saving and with less steps. Black-Right-Pointing-Pointer The relatively uniform and continuous silver coating is obtained. Black-Right-Pointing-Pointer The effects of silver coating on cenospheres on conductivity were investigated. - Abstract: Silver-coated cenosphere composites are successfully fabricated by a modified electroless plating process that is modified by replacing the conventional pretreatment and sensitization steps by only using surface hydroxylation step to simplify the steps and reduce the overall cost of the coating process. Furthermore, the activation and electroless plating steps are merged into one step. The cenosphere particles are characterized by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction analysis (XRD) before and after the coating process. The relatively continuous and compact coating is obtained under the given coating conditions. The results indicated that the conductivity of Ag-coated cenospheres was improved with increasing the AgNO{sub 3} solution dosage and reaction time. It was also found that the optimum AgNO{sub 3} solution concentration was 0.05 mol/L, and the optimum range of reaction temperature was from 50 Degree-Sign C to 65 Degree-Sign C.

  17. Development of electroless Ni-Zn-P/nano-TiO2 composite coatings and their properties

    International Nuclear Information System (INIS)

    Ni-Zn-P-TiO2 composite coatings were successfully obtained on low carbon steel by electroless plating technique. Deposits were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive analysis (EDS) studies. The hardness and microstructure of as plated and heat treated Ni-Zn-P and Ni-Zn-P-TiO2 composite coatings were analyzed. The change in microstructure and higher hardness was noticed for heat treated composite. The corrosion resistance behavior of as plated and heat treated Ni-Zn-P and Ni-Zn-P-TiO2 coatings was investigated by anodic polarization, Tafel plots and electrochemical impedance spectroscopic (EIS) studies in 3.5 wt% NaCl solution. The composite coating exhibited enhanced corrosion resistance property over Ni-Zn-P coating.

  18. A plating method for metal coating of fiber Bragg grating

    Institute of Scientific and Technical Information of China (English)

    Yulong Li; Hua Zhang; Yan Feng; Gang Peng

    2009-01-01

    We present a method for metal coating optical fiber and in-fiber Bragg grating. The technology process which is based on electroless plating and electroplating method is described in detail. The fiber is firstly coated with a thin copper or nickel plate with electroless plating method. Then, a thicker nickel plate is coated on the surface of the conductive layer. Under the optimum conditions, the surfaces of chemical plating and electroplating coatings are all smooth and compact. There is no visible defect found in the cross-section. Using this two-step metallization method, the in-fiber Bragg grating can be well protected and its thermal sensitivity can be enhanced. After the metallization process, the fiber sensor is successfully embedded in the 42CrMo steel by brazing method. Thus a smart metal structure is achieved. The embedding results show that the plating method for metallization protection of in-fiber Bragg grating is effective.

  19. ELECTROLESS NICKEL DEPOSITION ON FRAXINUS MANDSHURICA VENEER MODIFIED WITH APTHS FOR EMI SHIELDING

    Directory of Open Access Journals (Sweden)

    Haibing Liu

    2010-08-01

    Full Text Available Electroless nickel deposition was carried out on Fraxinus mandshurica veneers for EMI shielding under a new activation process. In the process, Pd(II was absorbed on the surface of veneers modified with γ-aminopropyltrihydroxysilane (APTHS obtained from the hydrolysis of γ-aminopropyltriethoxysilane (APTES. After the reduction, electroless plating was successfully initiated, and Ni-P coating was deposited on the veneers. The activation process and resulting coating were characterized by XPS, SEM-EDS, and XRD. The metal deposition, surface resistivity, and electromagnetic shielding effectiveness were measured. XPS analysis proved that Pd(II was bonded to the amino group of APTHS and reduced to Pd(0. The coating was continuous, uniform, and compact. It consisted of 97.4 wt% nickel and 2.6 wt% phosphorus. XRD analysis showed that the coating was crystalline, which was related to the low phosphorus content. The plated Fraxinus mandshurica veneers exhibit good electro-conductivity with surface resistivity of 0.21Ω•cm-2 and higher electromagnetic shielding effectiveness of over 50dB in frequencies from 10 MHz to 1.5 GHz.

  20. Characterization of electroless nickel as a seed layer for silicon solar cell metallization

    Indian Academy of Sciences (India)

    Mehul C Raval; Chetan S Solanki

    2015-02-01

    Electroless nickel plating is a suitable method for seed layer deposition in Ni–Cu-based solar cell metallization. Nickel silicide formation and hence contact resistivity of the interface is largely influenced by the plating process and annealing conditions. In the present work, a thin seed layer is deposited from neutral pH and alkaline electroless nickel baths which are annealed in the range of 400–420°C for silicide morphology and contact resistivity studies. A minimum contact resistivity of 7 m cm2 is obtained for seed layer deposited from alkaline bath. Silicide formation for Pd-activated samples leads to uniform surface morphology as compared with unactivated samples due to non-homogeneous migration of nickel atoms at the interface. Formation of nickel phosphides during annealing and the presence of SiO2 at Ni–Si interface creates isolated Ni2Si–Si interface with limited supply of silicon. Such an interface leads to the formation of high resistivity metal-rich Ni3Si silicide phase which limits the reduction in contact resistivity.

  1. Thermophysical properties and microstructure of graphite flake/copper composites processed by electroless copper coating

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Qian; He, Xin-Bo; Ren, Shu-Bin; Zhang, Chen; Ting-Ting, Liu; Qu, Xuan-Hui, E-mail: quxh@ustb.edu.cn

    2014-02-25

    Highlights: • GF–copper composites were fabricated using a sparking plasma sintering, which involves coating GF with copper, using electroless plating technique. • The oriented graphite flake distributed homogeneously in matrix. • With the increase of flake graphite from 44 to 71 vol.%, the basal plane thermal conductivity of composites increases from 445 to 565 W m{sup −1} K{sup −1} and the thermal expansion of composites decreases from 8.1 to 5.0. • The obtained composites are suitable for electronic packaging materials. -- Abstract: This study focuses on the fabrication of thermal management material for power electronics applications using graphite flake reinforced copper composites. The manufacturing route involved electroless plating of copper on the graphite flake and further spark plasma sintering of composite powders. The relative density of the composites with 44–71 vol.% flakes achieved up to 98%. Measured thermal conductivities and coefficients of thermal expansion of composites ranged from 455–565 W m{sup −1} K{sup −1} and 8 to 5 ppm K{sup −1}, respectively. Obtained graphite flake–copper composites exhibit excellent thermophysical properties to meet the heat dispersion and matching requirements of power electronic devices to the packaging materials.

  2. Microstructure and mechanical properties of Ni-P-Si3N4 nanowire electroless composite coatings

    Science.gov (United States)

    Wang, Shilong; Huang, Xuefei; Gong, Mengxiao; Huang, Weigang

    2015-12-01

    In this paper, a new Ni-P-Si3N4 nanowire composite coating has been successfully prepared on AZ31 Mg substrate through electroless deposition technique. The effect of Si3N4 nanowire concentration in the plating bath on the surface morphology, hardness and wear behavior of the composite coatings have been investigated. The results show that when the concentrations of Si3N4 nanowire is 1.5 g/L, the morphology of composite coating appears the fine nodular structure. Moreover, the Si3N4 nanowire is uniformly dispersed in the coating at the 1.5 g/L concentrations of Si3N4 nanowire. But when the concentrations of Si3N4 nanowire in bath over 1.5 g/L, the coatings surface morphology become roughness and some pores appear on the coating surface because of the agglomeration of Si3N4 nanowire. As seen from the experiments results, the microhardness of the composite coating were significantly increased to about 790HV200 as plating, the friction coefficient and wear weight loss of the composite coating is both decreased to the 1/6 of conventional Ni-P electroless coating. These improvements have been attributed to the dispersion strengthening effect of Si3N4 nanowire.

  3. Comparative Study of Electroless Copper Film on Different Self-Assembled Monolayers Modified ABS Substrate

    Directory of Open Access Journals (Sweden)

    Jiushuai Xu

    2014-04-01

    Full Text Available Copper films were grown on (3-Mercaptopropyltrimethoxysilane (MPTMS, (3-Aminopropyltriethoxysilane (APTES and 6-(3-(triethoxysilylpropylamino-1,3,5- triazine-2,4-dithiol monosodium (TES self-assembled monolayers (SAMs modified acrylonitrile-butadiene-styrene (ABS substrate via electroless copper plating. The copper films were examined using scanning electron microscopy (SEM and X-ray diffraction (XRD. Their individual deposition rate and contact angle were also investigated to compare the properties of SAMs and electroless copper films. The results indicated that the formation of copper nuclei on the TES-SAMs modified ABS substrate was faster than those on the MPTMS-SAMs and APTES-SAMs modified ABS substrate. SEM images revealed that the copper film on TES-SAM modified ABS substrate was smooth and uniform, and the density of copper nuclei was much higher. Compared with that of TES-SAMs modified resin, the coverage of copper nuclei on MPTMS and APTES modified ABS substrate was very limited and the copper particle size was too big. The adhesion property test demonstrated that all the SAMs enhanced the interfacial interaction between copper plating and ABS substrate. XRD analysis showed that the copper film deposited on SAM-modified ABS substrate had a structure with Cu(111 preferred orientation, and the copper film deposited on TES-SAMs modified ABS substrate is better than that deposited on MPTMS-SAMs or APTES-SAMs modified ABS resins in electromigrtion resistance.

  4. Highly adhesive metal plating on Zylon fiber via iodine pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Fatema, Ummul Khair [Faculty of Textile Science and Technology, Shinshu University, 3-15-1 Tokida, Ueda, Nagano 386-8567 (Japan); Gotoh, Yasuo, E-mail: ygotohy@shinshu-u.ac.jp [Faculty of Textile Science and Technology, Shinshu University, 3-15-1 Tokida, Ueda, Nagano 386-8567 (Japan)

    2011-11-01

    Highly adhesive metal plating was performed on poly(p-phenylene-2,6-benzobisoxazole) fiber named Zylon via iodine pretreatment followed by electroless plating. First, iodine components were selectively doped into the inner part of the fiber near the surface through iodine vapor exposure. The doped iodine was converted to palladium iodide particles by treating with palladium chloride solution. After the reduction of the iodide to metal palladium particles, electroless copper plating was conducted on the fiber. A uniform copper layer was deposited on the fiber surface and exhibited high durability in durability tests such as ultrasonic exposure, tape peeling-off, and corrosion in NaCl solution. This durability was attributed to the palladium particles formed at the fiber surface that served as an anchor for the plated layer as well as an electroless plating catalyst. The plated fibers also possessed electrical conductivity. Although the tensile strength of the Zylon fiber decreased from 5.8 to 4.9 GPa after undergoing the pretreatment and plating processes, the light shielding effect improved the light resistance of the plated fibers in terms of tensile properties. After 18 days of xenon lamp exposure, the plated fibers retained 74% of its initial strength, whereas that of untreated fibers decreased to 43%.

  5. Highly adhesive metal plating on Zylon fiber via iodine pretreatment

    International Nuclear Information System (INIS)

    Highly adhesive metal plating was performed on poly(p-phenylene-2,6-benzobisoxazole) fiber named Zylon via iodine pretreatment followed by electroless plating. First, iodine components were selectively doped into the inner part of the fiber near the surface through iodine vapor exposure. The doped iodine was converted to palladium iodide particles by treating with palladium chloride solution. After the reduction of the iodide to metal palladium particles, electroless copper plating was conducted on the fiber. A uniform copper layer was deposited on the fiber surface and exhibited high durability in durability tests such as ultrasonic exposure, tape peeling-off, and corrosion in NaCl solution. This durability was attributed to the palladium particles formed at the fiber surface that served as an anchor for the plated layer as well as an electroless plating catalyst. The plated fibers also possessed electrical conductivity. Although the tensile strength of the Zylon fiber decreased from 5.8 to 4.9 GPa after undergoing the pretreatment and plating processes, the light shielding effect improved the light resistance of the plated fibers in terms of tensile properties. After 18 days of xenon lamp exposure, the plated fibers retained 74% of its initial strength, whereas that of untreated fibers decreased to 43%.

  6. Effect of temperature on structure and corrosion resistance for electroless NiWP coating

    Indian Academy of Sciences (India)

    M Q YU; Q QIAO; F YOU; C L LI; Y ZHAO; Z Z XIAO; H L LUO; Z F XU; KAZUHIRO MATSUGI; J K YU

    2016-04-01

    The effect of plating temperatures between 60 and 90$^{\\circ}$C on structure and corrosion resistance for electroless NiWP coatings on AZ91D magnesium alloy substrate was investigated. Results show that temperature has a significant influence on the surface morphology and corrosion resistance of the NiWP alloy coating. An increase in temperature will lead to an increase in coating thickness and form a more uniform and dense NiWP coatings. Moreover, cracks were observed by SEM in coating surface and interface at the plating temperature of 90$^{\\circ}$C. Coating corrosion resistance is highly dependent on temperature according to polarization curves. The optimum temperature isfound to be 80$^{\\circ}$C and the possible reasons of corrosion resistance for NiWP coating have been discussed.

  7. GaN Nanowires Synthesized by Electroless Etching Method

    KAUST Repository

    Najar, Adel

    2012-01-01

    Ultra-long Gallium Nitride Nanowires is synthesized via metal-electroless etching method. The morphologies and optical properties of GaN NWs show a single crystal GaN with hexagonal Wurtzite structure and high luminescence properties.

  8. 改善印制电路板化学镀镍耐蚀性的研究进展%Research progress of improvement of corrosion resistance of electroless nickel coating on printed circuit board

    Institute of Scientific and Technical Information of China (English)

    冯立; 何为; 黄雨新; 何杰; 徐缓

    2013-01-01

    在印制电路板化学镀镍/金过程中,镍、金原子固有的结构特征使镍镀层极易被氧化腐蚀,从而影响镀层的可焊性。从化学镀Ni-P基多元合金,引入纳米粒子和稀土材料,以及化学镀Ni-B合金三方面,介绍了改善印制电路板化学镀镍层耐蚀性的研究现状。对印制电路板化学镀镍耐蚀性的改善方法提出了建议。%Oxidation corrosion of nickel coating occurs easily during the electroless nickel/gold plating process on the surface of printed circuit board because of the inherent structure features of nickel and gold atoms, thus affecting the solderability of coating. The research progress of improvement of corrosion resistance of electroless nickel coating on printed circuit board was introduced from three aspects including electroless Ni-P-based multicomponent alloy plating, introduction of nanoparticles and rare earth materials, and electroless Ni-B alloy. Some suggestions about improvement method of corrosion resistance of electroless nickel coating on printed circuit board were proposed.

  9. Electroless Fabrication of Cobalt Alloys Nanowires within Alumina Template

    OpenAIRE

    Nazila Dadvand; Kipouros, Georges J.

    2007-01-01

    A new method of nanowire fabrication based on electroless deposition process is described. The method is novel compared to the current electroless procedure used in making nanowires as it involves growing nanowires from the bottom up. The length of the nanowires was controlled at will simply by adjusting the deposition time. The nanowires were fabricated within the nanopores of an alumina template. It was accomplished by coating one side of the template by a thin layer of palladium in order t...

  10. 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.

  11. Preparation and Study of Electromagnetic Interference Shielding Materials Comprised of Ni-Co Coated on Web-Like Biocarbon Nanofibers via Electroless Deposition

    OpenAIRE

    Xiaohu Huang; Bo Dai; Yong Ren; Jing Xu; Pei Zhu

    2015-01-01

    Electromagnetic interference (EMI) shielding materials made of Ni-Co coated on web-like biocarbon nanofibers were successfully prepared by electroless plating. Biocarbon nanofibers (CF) with a novel web-like structure comprised of entangled and interconnected carbon nanoribbons were obtained using bacterial cellulose pyrolyzed at 1200°C. Paraffin wax matrix composites filled with different loadings (10, 20, and 30 wt%, resp.) of CF and Ni-Co coated CF (NCCF) were prepared. The electrical cond...

  12. The pH-sensitive Pd nanoparticles as ink for ink-jet printing technology and electroless Cu metallic patterns on indium-doped tin oxide substrate

    Energy Technology Data Exchange (ETDEWEB)

    Tseng, Chun-Chieh; Lin, Yi [Medical Device Section, Medical Devices and Opto-Electronics Equipment Department, Metal Industries Research and Development Centre, Kaohsiung 802, Taiwan (China); Liu, Tsai-Yun [Department of Mechanical Engineering and Graduate Institute of Mechanical and Precision Engineering, National Kaohsiung University of Applied Sciences, Kaohsiung 807, Taiwan (China); Nian, Yan-Yu [Graduate School of Defense Science, Chung Cheng Institute of Technology, National Defense University, 335 Taiwan (China); Wang, Min-Wen, E-mail: mwwang@cc.kuas.edu.tw [Department of Mechanical Engineering and Graduate Institute of Mechanical and Precision Engineering, National Kaohsiung University of Applied Sciences, Kaohsiung 807, Taiwan (China); Ger, Ming-Der, E-mail: mingderger@gmail.com [Department of Chemical and Materials Engineering, Chung Cheng Institute of Technology, National Defense University, 335 Taiwan (China)

    2013-06-01

    In this work, a method to fabricate copper pattern on an indium-doped tin oxide (ITO) glass substrate is described. This method involves ink-jet printing of a pH-sensitive chitosan-g-polyvinyl acetate/Pd nanoparticle (CTS-g-PVAc-Pd) based ink on an untreated ITO plate to create the catalytic sites, onto which copper is subsequently deposited by an electroless plating method. To prepare the CTS-g-PVAc-Pd nanoparticles, a pH-sensitive chitosan-g-polyvinyl acetate (CTS-g-PVAc) copolymer is utilized to self-reduce Pd nanoparticles. The pH-sensitive CTS chains function as stabilizing agent for noble metal nanoparticles in acidic ink solution. On the other hand, CTS-g-PVAc copolymers convert to hydrophilic CTS-g-poly(vinyl alcohol) via alkali hydrolysis during the electroless copper plating. Therefore, the copper film with dramatically enhanced adhesion is formed on the surface of ITO glass without special pretreatment step before electroless deposition of copper film. Our results show that this process yields copper line with width down to 60 μm and ITO plated with the copper coating has good electrical conductivity, with an electrical resistivity of about 5.4 μΩ cm. - Highlights: • Chitosan-g-polyvinyl acetate copolymer provides reducing environment for Pd nanoparticles. • pH-sensitive Pd nanoparticles as ink for ink-jet printing. • Patterning Pd catalyst for the electroless deposition of copper patterns. • Method to fabricate copper patterns on In-doped tin oxide substrates. • Ink-jet printing can be directly and easily applied to fabricate metal patterns.

  13. Preparation and in-vitro Antibacterial Evaluation of Electroless Silver Coated Polymers.

    Science.gov (United States)

    Fazeli, Mohammad Reza; Hosseini, Vahid; Shamsa, Fazel; Jamalifar, Hossein

    2010-01-01

    Long-term use of indwelling medical catheters has often been hindered by catheter-associated nosocomial infections. In this study the effectiveness of silver coating of polystyrene and polyethylene polymers was investigated. Polymer pieces of 2 cm(2) each were coated with a thin layer of silver using electroless plating technique. Silver-coated polymers were challenged with cultures of four different microorganisms known for their involvement in nosocomial infections in both solid and broth media. The tested bacteria included Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli and Pseudomonas aeruginosa. Silver release from the coated polymers was 2-5 μg/cm(2) which was confirmed by chemical and biological methods. The silver coating thickness ranged between 20-450 nm. P. aeruginosa and S. aureus were the most adherent bacteria to polystyrene sheets while E. coli showed minimum adherence effect. The survival rate of different bacteria after 80 min in a time course experiment tended to dominate E. coli as the most sensitive bacteria to the effect of silver with zero survival rate while around 4% of P. aeruginosa were detected after same period. Silver coating of indwelling polymers by electroless technique seems promising in combating nosocomial infections due to long-term catheterization. PMID:24363735

  14. Tribological characteristics of electroless Ni-P-MoS{sub 2} composite coatings at elevated temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Li Zhen; Wang Jingbo; Lu Jinjun [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Meng Junhu, E-mail: jhmeng@licp.cas.cn [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China)

    2013-01-01

    Highlights: Black-Right-Pointing-Pointer Uniform Ni-P-MoS{sub 2} composite coatings are deposited by electroless plating. Black-Right-Pointing-Pointer Friction coefficient of composite coating decreases with the increase of temperature. Black-Right-Pointing-Pointer Formation of lubricious oxide film leads to excellent tribological property. - Abstract: Ni-P-MoS{sub 2} composite coatings were deposited on AISI-1045 steel plate by electroless plating followed by a heat treatment at 300 Degree-Sign C for 2 h. The high-temperature tribological characteristics of the composite coatings were evaluated under dry sliding conditions in a tribometer with ball-on-disk configuration. The effect of the co-deposition of MoS{sub 2} on the friction and wear behaviors of composite coatings at elevated temperature was investigated. Scanning electron microscopy was used to determine the morphology of the worn surface of composite coating. The chemical states of some typical elements on the worn surfaces were determined by X-ray photoelectron spectroscope. The results indicate that friction coefficient of the composite coatings decreases with the increase of test temperature up to 500 Degree-Sign C, and the best tribological properties of Ni-P-MoS{sub 2} composite coatings are achieved at 400 Degree-Sign C. The worn surface of Ni-P-MoS{sub 2} composite coatings are characterized by mild scuffing and deformation. The improvement of tribological properties of the composite coatings was attributed to the formation of the lubricious oxide film composed of oxides of Ni and Mo at high temperatures. With the test temperature increasing to 600 Degree-Sign C, the tribological properties of the composite coating begin to deteriorate due to softening of the coating.

  15. Electroless Ni-B-W coatings for improving hardness, wear and corrosion resistance: Nanašanje Ni-B-W s cementacijskim galvaniziranjem za izboljšavo trdote, obrabe in odpornosti proti koroziji:

    OpenAIRE

    Aydeniz, Ali Imre; Calli, Cagdas; Dil, Gökce; Göksenli, Ali; MUHAFFEL, Faiz; Yüksel, Behiye

    2013-01-01

    In this study the formation of a Ni-B-W coating on steel using an electroless plating process and evaluation of the hardness, wear and corrosion resistance was analyzed. The Ni-B-W coating was prepared using an alkaline borohydride-reduced electroless nickel bath. Scanning electron microscopy (SEM) of the cross-sectional view of the Ni-B-W coating was analyzed and the layer characteristics were investigated. The Ni-B-W coating was characterized using XRD. The study reveals that the Ni-B-W coa...

  16. Effect of Processing Parameters on the Protective Quality of Electroless Nickel-Phosphorus on Cast Aluminium Alloy

    OpenAIRE

    Olawale Olarewaju Ajibola; Daniel Toyin Oloruntoba; Adewuyi, Benjamin O.

    2015-01-01

    The effects of temperature, pH, and time variations on the protective amount and quality of electroless nickel (EN) deposition on cast aluminium alloy (CAA) substrates were studied. The temperature, pH, and plating time were varied while the surface condition of the substrate was kept constant in acid or alkaline bath. Within solution pH of 5.0–5.5 range, the best quality is obtained in acid solution pH of 5.2. At lower pH (5.0–5.1), good adhesion characterised the EN deposition. Within the r...

  17. Effect of Annealing Temperature on Hardness and Wear Resistance of Electroless Ni-B-Mo Coatings

    Science.gov (United States)

    Serin, Ihsan Gökhan; Göksenli, Ali

    2015-06-01

    Formation of nickel-boron-molybdenum (Ni-B-Mo) coating on steel by electroless plating and evaluation of their morphology, hardness and tribological properties post heat treatment at different temperatures for 1 h is investigated. The 25 μm thick coating is uniform and adhesion between the substrate and coating is good. Ni-B-Mo coating was amorphous-like structure in their as-plated condition and by 400°C heat-treated coating, nickel fully crystallized and nickel borides and molybdenum carbide were formed. All coatings exhibited higher hardness than the substrate steel. Hardness values of all coatings up to 400°C did not change distinctively but decreased partly beyond 400°C. Friction coefficient reached lowest value post heat treatment at 300°C but later increased with increasing tempering temperature. Wear resistance was lowest in as-plated coating; however it reached the highest value at 300°C. Worn surface of the coatings showed the abrasive wear as the dominant wear mechanism. An additional adhesive wear mechanism was detected in coating tempered at 550°C. Moreover, our results confirmed that the molybdenum addition improved the thermal stability of the resulting coating. Therefore, Ni-B-Mo coating has potential for application in precision mould, optical parts mould or bipolar plates, where thermal stability is essential.

  18. Microwave absorption of electroless Ni-Co-P-coated SiO2 powder

    International Nuclear Information System (INIS)

    Ni-Co-P-coated SiO2 particles were prepared using electroless plating method. The morphology, crystal structure, surface compositions, magnetic and microwave absorption properties of the composite powder were investigated by scanning electron microscopy, X-ray diffraction analysis, X-ray photoelectron spectroscopy, vibrating sample magnetometer and vector network analyzer, respectively. It was found that the silica powder was successfully coated with Ni-Co-P alloy. The ultrafine Ni-Co-P-SiO2 powder-paraffin wax composite possesses excellent microwave absorption properties. The maximum microwave loss reaches -48.6 dB at 4.2 GHz with a thickness of 3.10 mm. The intrinsic reasons for microwave absorption were also investigated.

  19. Process and properties of electroless Ni-W-B amorphous electrical resistance film

    Institute of Scientific and Technical Information of China (English)

    ZHU Xiao-yun; GUO Zhong-cheng; XU Rui-dong

    2004-01-01

    The process and properties of electroless plating Ni-W-B alloy have been studied. The results show that the deposits containing W and B are obtained, and the deposition rate of the bath is increased with increase of W content when a certain amount of sodium tungstate solution is added in the Ni-B bath. The Ni-W-B alloy is amorphous as deposition and its resistivity increases directly with the increase of W content in the coating, but decreases gradually with increasing the deposit thickness. XRD and SEM show that the distributions of W and B in the Ni-W-B alloy film are very uniform and dispersed without any segregation.

  20. Copper/bamboo fabric composite prepared via a silver catalytic electroless deposition process for electromagnetic shielding

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Qian; Lu, Yinxiang [Fudan Univ., Shanghai (China). Dept. of Materials Science

    2013-09-15

    Copper/bamboo fabric composite prepared via a silver catalytic electroless plating process is reported. The microstructure of the composite was analyzed by means of scanning electron microscopy, which illustrated that the copper coating was composed of spherical particles and clusters. The composition and chemical state of the metal layer were measured using X-ray diffraction and energy-dispersive X-ray analysis spectra; copper and a small amount of nickel were detected. Mechanical properties were measured based on a standard (ISO 13934-1:1999) for the fabrics with and without copper coating. The breaking force for the composite was improved by about 16.8% compared to uncoated bamboo fabric. The electromagnetic interference shielding effectiveness of the composite was more than 40 dB at frequencies ranging from 0.2 to 1000MHz. The copper coating on bamboo fabric passed the Scotch {sup registered} -tape test. (orig.)

  1. Electromagnetic Interference Shielding Properties of Electroless Nickel-coated Carbon Fiber Paper Reinforced Epoxy Composites

    Institute of Scientific and Technical Information of China (English)

    CHEN Wei; WANG Jun; WANG Tao; WANG Junpeng; XU Renxin; YANG Xiaoli

    2014-01-01

    Carbon fibers (CFs) were coated with a nickel-phosphorus (Ni-P) film using an electroless plating process. The morphology, elemental composition and phases in the coating layer of the CFs were investigated by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD), respectively. Wet paper-making method was used to prepare nickle coated carbon fiber paper (NCFP). Vacuum assisted infusion molding process (VAIMP) was employed to manufacture the NCFP reinforced epoxy composites, and carbon fiber paper (CFP) reinforced epoxy composites were also produced as a comparison. Electromagnetic interference (EMI) shielding properties of the composites were measured in the 3.22-4.9 GHz frequency range using waveguide method. Both NCFP and CFP reinforced epoxy composites of 0.5 mm thickness exhibited high EMI shielding effectiveness (SE) at 8wt%fiber content, 35 dB and 30 dB, respectively, and reflection was the dominant shielding mechanism.

  2. Mechanical and electrochemical properties of ultrasonic-assisted electroless deposition of Ni–B–TiO{sub 2} composite coatings

    Energy Technology Data Exchange (ETDEWEB)

    Niksefat, Vahid; Ghorbani, Mohammad, E-mail: ghorbani@sharif.edu

    2015-06-05

    Highlights: • Ni–B–TiO{sub 2} coatings developed by ultrasonic-assisted electroless method. • Titania improves corrosion resistance and hardness of the Ni–B as-plated coatings. • Titania increases the surface film resistance of the Ni–B as-plated coatings. - Abstract: Nickel–Boron–Titania (Ni–B–TiO{sub 2}) composite coatings were successfully obtained on mild steel (St-37) by simultaneous electroless deposition. TiO{sub 2} particles were dispersed in a suspension by ultrasonic irradiation. The surface morphology, particle size, elemental composition and phase analysis of the coatings were characterized by scanning electron microscopy (SEM), inductively coupled plasma (ICP) and X-ray diffraction (XRD). The hardness and friction coefficient of as- plated and heat treated Ni–B and Ni–B–TiO{sub 2} composite coatings were determined by Vickers diamond indentation and indentation scratch tests and compared with Ni–B coatings. As a result, the hardness (1263 HV) of the as-plated Ni–B–TiO{sub 2} coatings was improved significantly. In addition, the corrosion resistance behavior of the as-plated and heat treated Ni–B and Ni–B–TiO{sub 2} coatings were analyzed by anodic polarization and electrochemical impedance spectroscopic (EIS) studies in a 3.5 wt.% NaCl solution. The as-plated composite coatings (Ni–B–TiO{sub 2}) exhibited enhanced corrosion resistance (0.2 μA/cm{sup 2}) property over Ni–B coatings.

  3. Kinetics of electroless deposition: the copper-dimethylamine borane system.

    Science.gov (United States)

    Plana, Daniela; Campbell, Andrew I; Patole, Samson N; Shul, Galyna; Dryfe, Robert A W

    2010-06-15

    A kinetic study of the electroless deposition of copper on gold, using dimethylamine borane (DMAB) as a reducing agent, has been carried out. The copper deposition rate in the electroless bath was determined to be 50 nm min(-1), through electrochemical stripping of the copper deposits as well as from direct measurements of the film thickness using atomic force microscopy (AFM). Comparison with a galvanic cell setup, where the two half-reactions were physically separated, yielded a lower deposition rate of 30 nm min(-1). An important kinetic effect of the surface on the oxidation of the reducing agent, and thus on the overall process, was therefore revealed. The efficiency of the process was measured over time, revealing the contribution of side reactions in the cathodic half-cell, particularly during the initial stages of the electroless process.

  4. High-temperature measurement using Cu-plating fiber Bragg grating for metal smart structure applications

    Science.gov (United States)

    Chang, Tianying; Jia, Lei; Sui, Qingmei; Cui, Hong-Liang

    2014-03-01

    High-temperature experiments for electroless Cu-plating Fiber Bragg Grating (FBG) indicate that Cu-plating FBG can measure high-temperature up to (even beyond) 300°C and it has high linearity, accuracy and repeatability. We can control Cu-plating FBG's temperature sensitivity by controlling plating layer's thickness. Temperature sensitivity of FBG with Cu-plating can be improved by more than three times with no less than 300μmthick coating by electroless and electrical Cu-plating. Such FBG can be soldered onto metal structures to get good bonding with the structure. As a result, such fiber sensors can get good protection, and high-temperature monitoring of smart structure is obtained.

  5. Effect of Annealing Temperature on the Corrosion Resistance of Electroless Ni-B-Mo Coatings

    Science.gov (United States)

    Serin, Ihsan Gökhan; Göksenli, Ali; Yüksel, Behiye; Yildiz, Rasid Ahmed

    2015-08-01

    The Ni-B-Mo coating on steel by electroless plating and the evaluation of the morphology and corrosion performance after applying heat treatments at different temperatures for 1 h were investigated in this study. The 25-μm-thick coating was uniform and adhesion between the substrate and the coating was good. The coating consisted of an amorphous-like structure in their as-plated condition, and after annealing at 400 °C for 1 h, crystallized nickel, nickel borides, and molybdenum carbide were formed. Immersion tests in 10% HCl solution and potentiodynamic polarization measurements in 3.5% NaCl aqueous solution were applied to investigate corrosion resistance. The corrosion performance of heat-treated coatings was compared with steel and the as-plated coating. By increasing the annealing temperature, corrosion potential shifted toward a noble direction, corrosion current density decreased and the weight loss of specimens decreased, demonstrating an increase in corrosion resistance. Best corrosion performance was achieved by the coating heat treated at 550 °C.

  6. Optimizing growth conditions for electroless deposition of Au films on Si(111) substrates

    Indian Academy of Sciences (India)

    Bhuvana; G U Kulkarni

    2006-10-01

    Electroless deposition of Au films on Si(111) substrates from fluorinated-aurate plating solutions has been carried out at varying concentrations, deposition durations as well as bath temperatures, and the resulting films were characterized by X-ray diffraction, optical profilometry, atomic force microscopy and scanning electron microscopy. Depositions carried out with dilute plating solutions (< 0.1 mM) at 28°C for 30 min produce epitaxial films exhibiting a prominent Au(111) peak in the diffraction patterns, while higher concentrations or temperatures, or longer durations yield polycrystalline films. In both epitaxial and polycrystalline growth regimes, the film thickness increases linearly with time, however, in the latter case, at a rate an order of magnitude higher. Interestingly, the surface roughness measured using atomic force microscopy shows a similar trend. On subjecting to annealing at 250°C, the roughness of the film decreases gradually. Addition of poly (vinylpyrrolidone) to the plating solution is shown to produce a X-ray amorphous film with nanoparticulates capped with the polymer as evidenced by the core-level photoelectron spectrum. Nanoindentation using AFM has shown the hardness of the films to be much higher (∼ 2.19 GPa) than the bulk value.

  7. Broadband infrared absorption enhancement by electroless-deposited silver nanoparticles

    DEFF Research Database (Denmark)

    Gritti, Claudia; Raza, Søren; Kadkhodazadeh, Shima;

    2016-01-01

    . Optical characterization confirms that the random array of electroless-deposited NPs improves absorption by up to 20% in a broadband of nearinfrared frequencies from the bandgap edge to 2000 nm. Due to the small filling fraction of particles, the reflection in the visible range is practically unchanged...

  8. Highly adhesive metal plating on Zylon ® fiber via iodine pretreatment

    Science.gov (United States)

    Fatema, Ummul Khair; Gotoh, Yasuo

    2011-11-01

    Highly adhesive metal plating was performed on poly(p-phenylene-2,6-benzobisoxazole) fiber named Zylon® via iodine pretreatment followed by electroless plating. First, iodine components were selectively doped into the inner part of the fiber near the surface through iodine vapor exposure. The doped iodine was converted to palladium iodide particles by treating with palladium chloride solution. After the reduction of the iodide to metal palladium particles, electroless copper plating was conducted on the fiber. A uniform copper layer was deposited on the fiber surface and exhibited high durability in durability tests such as ultrasonic exposure, tape peeling-off, and corrosion in NaCl solution. This durability was attributed to the palladium particles formed at the fiber surface that served as an anchor for the plated layer as well as an electroless plating catalyst. The plated fibers also possessed electrical conductivity. Although the tensile strength of the Zylon® fiber decreased from 5.8 to 4.9 GPa after undergoing the pretreatment and plating processes, the light shielding effect improved the light resistance of the plated fibers in terms of tensile properties. After 18 days of xenon lamp exposure, the plated fibers retained 74% of its initial strength, whereas that of untreated fibers decreased to 43%.

  9. Determination of electroless deposition by chemical nickeling

    Directory of Open Access Journals (Sweden)

    M. Badida

    2013-07-01

    Full Text Available Increasing of technical level and reliability of machine products in compliance with the economical and ecological terms belongs to the main trends of the industrial development. During the utilisation of these products there arise their each other contacts and the interaction with the environment. That is the reason for their surface degradation by wear effect, corrosion and other influences. The chemical nickel-plating allows autocatalytic deposition of nickel from water solutions in the form of coherent, technically very profitable coating without usage of external source of electric current. The research was aimed at evaluating the surface changes after chemical nickel-plating at various changes of technological parameters.

  10. Preparation and characterization of electroless Ni–B/nano-SiO2, Al2O3, TiO2 and CuO composite coatings

    Indian Academy of Sciences (India)

    Dursun Ekmekci̇; Ferhat Bülbül

    2015-06-01

    Ni–B/SiO2, Al2O3, TiO2 and CuO composite coatings were successfully obtained by the electroless plating technique. Dispersible SiO2, Al2O3, TiO2 and CuO nanoparticles were co-deposited with electroless Ni–B coating onto AISI-304 steel substrates. Deposits were characterized for its structural properties by X-ray diffraction (XRD). XRD results showed a broad peak of Ni–B and low intensity composite nanoparticle peaks. The surface and cross-section morphology of samples were analysed using a scanning electron microscope (SEM). Surface analysis showed that the incorporation in Ni–B matrix of nano-SiO2, Al2O3, TiO2 and CuO particles increases the nodularity of composite coatings. The deposits are composed of a columnar structure grown along the vertical direction of the substrate surface. The results also show that electroless nanocomposite coatings tend to have greater microhardness compared with the coating without nanoparticles. The increase in the microhardness of the nanocomposite coatings reported in this study is attributed to an effect of dispersion strengthening of ceramic particles in the Ni–B matrix.

  11. Determination of electroless deposition by chemical nickeling

    OpenAIRE

    Badida, M.; M. Gombár; L. Sobotová; J. Kmec

    2013-01-01

    Increasing of technical level and reliability of machine products in compliance with the economical and ecological terms belongs to the main trends of the industrial development. During the utilisation of these products there arise their each other contacts and the interaction with the environment. That is the reason for their surface degradation by wear effect, corrosion and other influences. The chemical nickel-plating allows autocatalytic deposition of nickel from water solutions in the fo...

  12. Activator-assisted electroless deposition of copper nanostructured films

    Institute of Scientific and Technical Information of China (English)

    Varsha R. Mehto; R. K. Pandey

    2014-01-01

    This paper showed simple and effective synthesis of copper nanoparticles within controlled diameter using direct electroless deposition on glass substrates, following the sensitization and activation steps. Electroless-deposited metals, such as Cu, Co, Ni, and Ag, and their alloys had many advantages in micro- and nanotechnologies. The structural, morphological, and optical properties of copper deposits were characterized using X-ray diffraction (XRD), atomic force microscopy (AFM), and UV-Vis spectroscopy. The structural data was further analyzed using the Rietveld refinement program. Structural studies reveal that the deposited copper prefers a (111) orientation. AFM studies suggest the deposited materials form compact, uniform, and nanocrystalline phases with a high tendency to self-organize. The data show that the particle size can be controlled by controlling the activator concentration. The absorption spectra of the as-deposited copper nanoparticles reveal that the plasmonic peak broadens and exhibits a blue shift with decreasing particle size.

  13. Electroless deposition of conducting polymers using the scanning electrochemical microscope

    Energy Technology Data Exchange (ETDEWEB)

    Borgwarth, K.; Ricken, C.; Heinze, J. [Freiburg Univ. (Germany). Inst. fuer Physikalische Chemie; Rohde, N.; Hallensleben, M.L.; Mandler, D.

    1999-10-01

    Micropatterning of organic substances using scanning electrochemical microscopy (SECM) is presented as a versatile, reproducible method for obtaining patterned materials of mesoscopic resolution-between that of conventional lithography and scanning tunneling microscopy or atomic force microscopy. In this technique, conducting polymer is electrolessly deposited on different substrates. It is reported that both flat layers and sets of thin needles protruding from the surface may be formed simply by varying the nature of the redox mediator. (orig.)

  14. Electroless nickel, alloy, composite and nano coatings - A critical review

    OpenAIRE

    Sudagar, Jothi; Lian, Jianshe; Sha, Wei

    2013-01-01

    The development of metal deposition processes based on electroless nickel, alloy and composite coatings on various surfaces has witnessed a surge in interest among researchers, with many recent applications made possible from many excellent properties. In recent years, these coatings have shown promising corrosion and wear resistance properties and large number of newer developments became most important from macro to nano level applications. After a brief review of the fundamental aspects un...

  15. Potentiodynamic Polarization Behaviour of Electroless Ni-P-W Coatings

    OpenAIRE

    Supriyo Roy; Prasanta Sahoo

    2012-01-01

    This paper deals with the synthesis of electroless Ni-P-W coatings on mild steel substrate followed by furnace-annealing process. Corrosion behaviors of the coatings after heat treatments at various annealing temperatures are evaluated by potentiodynamic polarization test using 3.5% sodium chloride solution. The electrochemical parameters, that is, corrosion potential and corrosion current density, are optimized for maximum corrosion resistance using Taguchi-based grey relational analysis, co...

  16. Electroless Deposition of Ni-Cu-P Coatings Containing Nano-Al2O3 Particles and Study of Its Corrosion Protective Behaviour in 0.5 M H2SO4

    OpenAIRE

    H. Ashassi-Sorkhabi; Aminikia, H.; R. Bagheri

    2014-01-01

    Ni-Cu-P/nano-Al2O3 composite coatings are prepared on mild steel from an alkaline electroless plating bath containing different concentrations of Al2O3 nanoparticles. The protective effect of codeposited nanoparticles on the corrosion behaviour of the coatings is studied in 0.5 M H2SO4 solution. The electrochemical methods, that is, electrochemical noise (ECN), electrochemical impedance spectroscopy (EIS), and polarization measurements, are used to characterize the corrosion properties of the...

  17. 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.

  18. Effectiveness of nickel plating in inhibiting atmospheric corrosion of copper alloy contacts

    Energy Technology Data Exchange (ETDEWEB)

    Ernest, T.; Sorensen, R.; Guilinger, T.

    1997-12-31

    A series of tests was run to determine the effect of Ni plating thickness on connector contact resistance. Copper coupons were plated with an electrolytic nickel strike followed by electroless nickel to produce Ni layers of 10, 20, 55 and 100 {micro}in. The coupons were then exposed to a simulated industrial environment. Pore corrosion was observed after the exposure, which correlated with Ni thickness. In a second series of tests, beryllium-copper four-tine contacts with 50 {micro}in of gold plate over electrolytic nickel strike/electroless-nickel plates of varying thickness were exposed the same corrosive environment. Contact resistance of mated pairs was monitored over a two-month period. The degradation in contact resistance correlated with the Ni thickness used in the connectors.

  19. Microwave absorbing properties of hollow microspheres plated with magnetic metal films

    Science.gov (United States)

    Kim, Sun-Tae; Kim, Sung-Soo

    2014-05-01

    Conductive and magnetic microspheres are fabricated through the electroless plating of Co, Co-10%Fe, Ni, and Ni-15%Fe films on hollow microspheres (cenospheres), and their high frequency electromagnetic and microwave absorbing properties are investigated in the composite specimens. The electroless plating of the metal films is conducted using a two-step process of surface sensitizing and metal plating. For the microspheres coated with the Co and Co-10%Fe films, impedance matching is not satisfied at all frequencies due to the small values of magnetic loss and dielectric constant. For the Ni-plated microsphere composites, the dielectric constant is too high to satisfy the impedance matching, which results in a small value of microwave absorbance. For the Ni-15%Fe thin film composite with appropriate magnetic permeability and dielectric permittivity, the impedance matching is satisfied in the GHz frequency and a lower value of reflection loss is predicted.

  20. Phase composition, microstructure and microhardness of electroless nickel composite coating co-deposited with SiC on cast aluminium LM24 alloy substrate

    OpenAIRE

    Franco, M.; Sha, W.; Malinov, S.; Rajendran, R

    2013-01-01

    Electroless Ni–P (EN) and composite Ni–P–SiC (ENC) coatings were developed on cast aluminium alloy substrate, LM24. The coating phase composition, microstructure and microhardness were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) and microhardness tester, respectively, on as-plated and heat-treated specimens. The original microstructure of the Ni–P matrix is not affected by the inclusion of the hard particles SiC. No formation of Ni–Si phase was observed up t...

  1. Characterisation of phase composition, microstructure and microhardness of electroless nickel composite coating co-deposited with SiC on casting aluminium LM24 alloy substrate

    OpenAIRE

    Franco, M.; Sha, Wei; Malinov, Savko

    2013-01-01

    Electroless Ni-P (EN) and composite Ni-P-SiC (ENC) coatings were developed on cast aluminium alloy, LM24. The coating phase composition, microstructure and microhardness were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) and microhardness tester, respectively, on as-plated and heat-treated specimens. The original microstructure of the Ni-P matrix is not affected by the inclusion of the hard particles SiC. No formation of Ni-Si phase was observed upto 500°C of ...

  2. Effect of pickling processes on the microstructure and properties of electroless Ni–P coating on Mg–7.5Li–2Zn–1Y alloy

    OpenAIRE

    Chunjie Xu; Liping Chen; Ling Yu; Jinxiao Zhang; Zhongming Zhang; Jincheng Wang

    2014-01-01

    The electroless plating Ni–P is prepared on the surface of Mg–7.5Li–2Zn–1Y alloys with different pickling processes. The microstructure and properties of Ni–P coating are investigated. The results show that the Ni–P coatings deposited using the different pickling processes have a different high phosphorus content amorphous Ni–P solid solution structure, and the Ni–P coatings exhibit higher hardness. There is higher phosphorus content of Ni–P amorphous coating using 125 g/L CrO3 and 110 ml/L H...

  3. Electroless deposition of Ni-P-nano-ZrO2 composite coatings in the presence of various types of surfactants.

    Science.gov (United States)

    Zielińska, Katarzyna; Stankiewicz, Alicja; Szczygieł, Irena

    2012-07-01

    Ni-P-nano-ZrO(2) coatings were produced using the electroless deposition technique. To prevent agglomeration of zirconia nanoparticles in the plating bath, various surfactant additives (anionic, cationic, and nonionic) were used. The most stable bath was obtained with the addition of dodecyltrimethylammonium bromide (DTAB). The impact of this surfactant on the deposition rate, coating composition, and topography, as well as ζ potential of particles, was examined. Surface morphology and composition of the Ni-P-nano-ZrO(2) composite coatings was analyzed by various techniques including scanning electron microscopy (SEM) equipped with in situ energy-dispersive X-ray (EDX) spectroscopy. Coatings with a clearly greater amount of zirconia (21.88-22.10 wt.%) were obtained from baths containing DTAB in concentrations equal to or above its critical micelle concentration (cmc). For these surfactant concentrations, the reduction of Ni and P content was observed. PMID:22498365

  4. 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.

  5. Tribological properties of electroless Ni-P-SiC composite coatings in rolling/sliding contact under boundary lubrication

    Institute of Scientific and Technical Information of China (English)

    Wei-Long Liu; Shu-Hue Hsieh; Shen-Jenn Hwang; Ting-Kan Tsai; Wen-Jauh Chen

    2007-01-01

    Ni-P-SiC composite coatings were prepared under a given bath composition and operation parameters of electroless plating. The tribological properties of the Ni-P-SiC composite coatings after annealing at 400°C for 1 h were tested in rolling/sliding contact under boundary lubrication condition using a two-roller tribometer. The measurement contained friction coefficient, contact surface temperature, contact electrical resistance, and wear rate of the Ni-P-SiC composite coatings under various slide to roll ratios, loads, and rolling speeds. For the simultaneous examination of the effect of the chosen parameters on the tribological properties of the Ni-P-SiC composite coatings, an orthogonal regression experimental design method was used.

  6. 钕铁硼磁体表面化学镀 Ni-Cu-P 合金工艺及性能研究%Process and Performance Study on Electroless Plating Ni-Cu-P Alloy on Nd-Fe-B Magnet

    Institute of Scientific and Technical Information of China (English)

    王勇; 张祖军

    2013-01-01

    This paper studies the process of plating Ni‐Cu‐P alloy on Nd‐Fe‐B magnet surface .The scanning electron microscopy (SEM ) pictures display Ni‐Cu‐P alloy coating is homogeneous cell structure .X‐ray diffraction pattern analysis results show this coating is in microcrystalline state .Therefore ,the Ni‐Cu‐P alloy coating has good corrosion resistance and wear resistance ,being able to meet the requirement of industrial application .%  研究了Nd-Fe-B磁体表面化学镀Ni-Cu-P合金的工艺过程。扫描电镜照片显示Ni-Cu-P合金镀层呈胞状结构,颗粒较均匀;X射线衍射图谱分析,该镀层为微晶状态。通过该工艺得到的 Ni -Cu-P合金镀层有良好的耐腐蚀性和耐磨性能,符合工业应用要求。

  7. Polystyrene as a zwitter resist in electron beam lithography based electroless patterning of gold

    Indian Academy of Sciences (India)

    T Bhuvana; G U Kulkarni

    2008-06-01

    The resist action of polystyrene (w, 2,600,000) towards electroless deposition of gold on Si(100) surface following cross-linking by exposing to a 10 kV electron beam, has been investigated employing a scanning electron microscope equipped with electron beam lithography tool. With a low dose of electrons (21 C/cm2), the exposed regions inhibited the metal deposition from the plating solution due to cross-linking—typical of the negative resist behaviour of polystyrene, with metal depositing only on the developed Si surface. Upon increased electron dosage (160 C/cm2), however, Au deposition took place even in the exposed regions of the resist, thus turning it into a positive resist. Raman measurement revealed amorphous carbon present in the exposed region that promotes metal deposition. Further increase in dosage led successively to negative (220 C/cm2) and positive (13,500 C/cm2) resist states. The zwitter action of polystyrene resist has been exploited to create line gratings with pitch as low as 200 nm and gap electrodes down to 80 nm.

  8. Stability of nonfouling electroless nickel-polytetrafluoroethylene coatings after exposure to commercial dairy equipment sanitizers.

    Science.gov (United States)

    Huang, Kang; Goddard, Julie M

    2015-09-01

    Application of nonfouling coatings on thermal processing equipment can improve operational efficiency. However, to enable effective commercial translation, a need exists for more comprehensive studies on the stability of nonfouling coatings after exposure to different sanitizers. In the current study, the influence of different commercial dairy equipment sanitizers on the nonfouling properties of stainless steel modified with electroless Ni-polytetrafluoroethylene (PTFE) coatings was determined. Surface properties, such as dynamic contact angle, surface energy, surface morphology, and elemental composition, were measured before and after the coupons were exposed to the sanitizers for 168 cleaning cycles. The fouling behavior of Ni-PTFE-modified stainless steel coupons after exposure was also evaluated by processing raw milk on a self-fabricated benchtop-scale plate heat exchanger. The results indicated that peroxide sanitizer had only minor effect on the Ni-PTFE-modified stainless steel surface, whereas chlorine- and iodine-based sanitizers influenced the surface properties drastically. The coupons after 168 cycles of exposure to peroxide sanitizer accumulated the least amount of fouling material (4.44±0.24mg/cm(2)) compared with the coupons exposed to the other 3 sanitizers. These observations indicated that the Ni-PTFE nonfouling coating retained antifouling properties after 168 cycles of exposure to peroxide-based sanitizer, supporting their potential application as nonfouling coatings for stainless steel dairy processing equipment. PMID:26142857

  9. Effects of Two Purification Pretreatments on Electroless Copper Coating over Single-Walled Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Zhong Zheng

    2014-01-01

    Full Text Available To achieve the reinforcement of copper matrix composite by single-walled carbon nanotubes, a three-step-refluxing purification of carbon nanotubes sample with HNO3-NaOH-HCl was proposed and demonstrated. A previously reported purification process using an electromagnetic stirring with H2O2/HCl mixture was also repeated. Then, the purified carbon nanotubes were coated with copper by the same electroless plating process. At the end, the effects of the method on carbon nanotubes themselves and on copper coating were determined by transmission electron microscope spectroscopy, scanning electron microscope spectroscopy, X-ray diffractometry, thermogravimetric analysis, Fourier transformed infrared spectroscopy, and energy dispersive spectrometry. It was clearly confirmed that both of the two processes could remove most of iron catalyst particles and carbonaceous impurities without significant damage to carbon nanotubes. The thermal stability of the sample purified by H2O2/HCl treatment was slightly higher than that purified by HNO3-NaOH-HCl treatment. Nevertheless, the purification by HNO3-NaOH-HCl treatment was more effective for carboxyl functionalization on nanotubes than that by H2O2/HCl treatment. The Cu-coating on carbon nanotubes purified by both purification processes was complete, homogenous, and continuous. However, the Cu-coating on carbon nanotubes purified by H2O2/HCl was oxidized more seriously than those on carbon nanotubes purified by HNO3-NaOH-HCl treatment.

  10. 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.

  11. Electroless deposition of Cu on multiwalled carbon nanotubes

    Institute of Scientific and Technical Information of China (English)

    YUAN Dingsheng; LIU Yingliang

    2006-01-01

    Copper has been deposited on the surface of multiwalled carbon nanotubes (MWNTs) and inside MWNTs by electroless deposition. The as-prepared Cu-MWNT composite materials have been characterized by X-ray diffractometer(XRD), transmission electron microscopy (TEM), and electrochemical measurement. XRD analyses showed that Cu was a face-centered cubic (fcc) structure. The average size of Cu was calculated by Scherrer's formula from XRD data, and it was11 nm. TEM revealed that Cu grains on the surface of MWNTs were uniform with the sizes of about 30-60 nm. The electrochemical measurement indicated that Cu-MWNT composite materials possessed fine electron conductivity.

  12. Electroless silver as an optical coating in an operational environment.

    Science.gov (United States)

    Nahrstedt, D; Glesne, T; McNally, J; Kenemuth, J; Magrath, B

    1996-07-01

    Long-term, independent experiments show a high degradation rate and short lifetime for electroless silver as a mirror coating operating at visible wavelengths in an observatory environment. Acid formed by water vapor mixing with sulfur in volcanic dust diffuses through pinholes in the coating generated during deposition. This causes internal corrosion and delamination after only 3-4 months. In addition, a layer of silver sulfide results in tarnish, which reduces reflectance. Rates of sulfidation and internal corrosion are shown to depend on the concentration of sulfur and the exposure rate. Comparisons of performance, lifetime, and the application process are made with bare aluminum and two variations of enhanced silver. PMID:21102764

  13. Carbon black dispersion pre-plating technology for printed wire board manufacturing. Final technology evaluation report

    Energy Technology Data Exchange (ETDEWEB)

    Folsom, D.W.; Gavaskar, A.R.; Jones, J.A.; Olfenbuttel, R.F.

    1993-10-01

    The project compared chemical use, waste generation, cost, and product quality between electroless copper and carbon-black-based preplating technologies at the printed wire board (PWB) manufacturing facility of McCurdy Circuits in Orange, CA. The carbon-black based preplating technology evaluated is used as an alternative process for electroless copper (EC) plating of through-holes before electrolytic copper plating. The specific process used at McCurdy is the BlackHole (BH) technology process, which uses a dispersion of carbon black in an aqueous solution to provide a conductive surface for subsequent electrolytic copper plating. The carbon-black dispersion technology provided effective waste reduction and long-term cost savings. The economic analysis determined that the new process was cost efficient because chemical use was reduced and the process proved more efficient; the payback period was less than 4 yrs.

  14. In-depth survey report of American Airlines plating facility

    Science.gov (United States)

    Mortimer, V. D., Jr.

    1982-12-01

    An in depth survey was conducted at the American Airlines Maintenance and Engineering Center as part of National Institute for Occupational Safety and Health (NIOSH) study evaluating measures to control occupational health hazards associated with the metal plating industry. This American Airlines plating facility, employing approximately 25 workers, is primarily engaged in plating hard chromium, nickel and cadmium on aircraft engine and landing gear parts. Six tanks were studied, including an electroless nickel tank. Area and personal samples for chromium, nickel, cadmium, and cyanide were collected. Ventilation airflow and tank dimensions were measured and data recorded on plating operations. The relationships between air contaminants emitted, local exhaust ventilation flow rate, tank size, and plating activity were evaluated.

  15. Comparison of galvanic displacement and electroless methods for deposition of gold nanoparticles on synthetic calcite

    Indian Academy of Sciences (India)

    Chamarthi K Srikanth; P Jeevanandam

    2012-11-01

    Gold nanoparticles have been deposited on synthetic calcite substrate by galvanic displacement reaction and electroless deposition methods. A comparative study has shown that electroless deposition is superior compared to galvanic displacement reaction for uniform deposition of gold nanoparticles on calcite. Characterization of the samples, prepared by two different deposition methods, was carried out by X-ray diffraction, transmission electron microscopy, field emission scanning electron microscopy (FE–SEM) and diffuse reflectance spectroscopy (DRS) measurements. FE–SEM studies prove that smaller nanoparticles of gold are deposited uniformly on calcite if electroless deposition method was employed and DRS measurements show the characteristic surface plasmon resonance of gold nanoparticles.

  16. Electroless silver coating of rod-like glass particles

    International Nuclear Information System (INIS)

    An electroless silver coating of rod-like glass particles was performed and silver glass composite powders were prepared to impart electrical conductivity to these non-conducting glass particles. The low density Ag-coated glass particles may be utilized for manufacturing conducting inorganic materials for electromagnetic interference (EMI) shielding applications and the techniques for controlling the uniform thickness of silver coating can be employed in preparation of biosensor materials. For the surface pretreatment, Sn sensitization was performed and the coating powders were characterized by scanning electron microscopy (SEM), focused ion beam microscopy (FIB), and atomic force microscopy (AFM) along with the surface resistant measurements. In particular, the use of FIB technique for determining directly the Ag-coating thickness was very effective on obtaining the optimum conditions for coating. The surface sensitization and initial silver loading for electroless silver coating could be found and the uniform and smooth silver-coated layer with thickness of 46 nm was prepared at 2 mol/l of Sn and 20% silver loading

  17. Electroless silver coating of rod-like glass particles.

    Science.gov (United States)

    Moon, Jee Hyun; Kim, Kyung Hwan; Choi, Hyung Wook; Lee, Sang Wha; Park, Sang Joon

    2008-09-01

    An electroless silver coating of rod-like glass particles was performed and silver glass composite powders were prepared to impart electrical conductivity to these non-conducting glass particles. The low density Ag-coated glass particles may be utilized for manufacturing conducting inorganic materials for electromagnetic interference (EMI) shielding applications and the techniques for controlling the uniform thickness of silver coating can be employed in preparation of biosensor materials. For the surface pretreatment, Sn sensitization was performed and the coating powders were characterized by scanning electron microscopy (SEM), focused ion beam microscopy (FIB), and atomic force microscopy (AFM) along with the surface resistant measurements. In particular, the use of FIB technique for determining directly the Ag-coating thickness was very effective on obtaining the optimum conditions for coating. The surface sensitization and initial silver loading for electroless silver coating could be found and the uniform and smooth silver-coated layer with thickness of 46 nm was prepared at 2 mol/l of Sn and 20% silver loading. PMID:18571859

  18. Preparation, characterization and microwave absorption properties of electroless Ni-Co-P-coated SiC powder

    International Nuclear Information System (INIS)

    Silicon carbide particles reinforced nickel-cobalt-phosphorus matrix composite coatings were prepared by two-step electroless plating process (pre-treatment of sensitizing and subsequent plating) for the application to lightweight microwave absorbers, which were characterized by scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), vibrating sample magnetometer (VSM) and vector network analyzer, respectively. The results show that Ni-Co-P deposits are uniform and mixture crystalline of α-Co and Ni3P and exhibit low-specific saturation magnetization and low coercivity. Due to the conductive and ferromagnetic behavior of the Ni-Co thin films, high dielectric constant and magnetic loss can be obtained in the microwave frequencies. The maximum microwave loss of the composite powder less than -32 dB was found at the frequency of 6.30 GHz with a thickness of 2.5 mm when the initial atomic ratio of Ni-Co in the plating bath is 1.5

  19. Preparation, characterization and microwave absorption properties of electroless Ni Co P-coated SiC powder

    Science.gov (United States)

    Li, Yongjie; Wang, Rui; Qi, Fengming; Wang, Chunming

    2008-05-01

    Silicon carbide particles reinforced nickel-cobalt-phosphorus matrix composite coatings were prepared by two-step electroless plating process (pre-treatment of sensitizing and subsequent plating) for the application to lightweight microwave absorbers, which were characterized by scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), vibrating sample magnetometer (VSM) and vector network analyzer, respectively. The results show that Ni-Co-P deposits are uniform and mixture crystalline of α-Co and Ni 3P and exhibit low-specific saturation magnetization and low coercivity. Due to the conductive and ferromagnetic behavior of the Ni-Co thin films, high dielectric constant and magnetic loss can be obtained in the microwave frequencies. The maximum microwave loss of the composite powder less than -32 dB was found at the frequency of 6.30 GHz with a thickness of 2.5 mm when the initial atomic ratio of Ni-Co in the plating bath is 1.5.

  20. Experimental study of the voids in the electroless copper deposits and the direct measurement of the void fraction based on the scanning electron microscopy images

    International Nuclear Information System (INIS)

    Electroless copper deposits were plated on epoxy substrates in various plating solutions at either a high operating temperature (60 deg. C) or a low one (45 deg. C). Cross section samples were made using epoxy resin cured in room temperature, and then ground, polished and over-etched. The scanning electron microscopy (SEM) images of the over-etched cross section samples show voids in low temperature deposits and solid structure in high temperature ones. The surface morphology images also indicated such structures in low temperature samples. The SEM image of the cross section of a stand-alone deposit prepared on stainless steel substrate shows similar voids observed on etched cross section samples on epoxy board substrates. An image processing program was written using MATLAB to identify the voids in the over-etched cross sections of the deposits from low temperature solutions and thus the void fraction can be directly measured and compared with the previously published simulation results.

  1. Hybrid Antifouling and Antimicrobial Coatings Prepared by Electroless Co-Deposition of Fluoropolymer and Cationic Silica Nanoparticles on Stainless Steel: Efficacy against Listeria monocytogenes.

    Science.gov (United States)

    Huang, Kang; Chen, Juhong; Nugen, Sam R; Goddard, Julie M

    2016-06-29

    Controlling formation, establishment, and proliferation of microbial biofilms on surfaces is critical for ensuring public safety. Herein, we report on the synthesis of antimicrobial nanoparticles and their co-deposition along with fluorinated nanoparticles during electroless nickel plating of stainless steel. Plating bath composition is optimized to ensure sufficiently low surface energy to resist fouling and microbial adhesion as well as to exert significant (>99.99% reduction) antimicrobial activity against Listeria monocytogenes. The resulting coatings present hybrid antifouling and antimicrobial character, can be applied onto stainless steel, and do not rely on leaching or migration of the antimicrobial nanoparticles to be effective. Such coatings can support reducing public health issues related to microbial cross-contamination in areas such as food processing, hospitals, and water purification. PMID:27268033

  2. Micro-scale abrasion behaviour of electroless Ni-P-SiC coating on aluminium alloy

    OpenAIRE

    Franco, M.; Sha, Wei; Malinov, Savko

    2014-01-01

    Electroless nickel (EN) and electroless nickel composite (ENC) coatings were deposited on aluminium alloy substrate, LM24. The micro abrasion test was conducted to study the wear behaviour of the coatings with the effect of SiC concentration. Microhardness of the coatings was tested also. The wear scars were analysed using optical microscope and scanning electron microscope (SEM). The wear resistance was found to be improved in composite coating that has higher microhardness as compared to pa...

  3. Influence of Process Parameters on Microhardness of Electroless Ni-B Coatings

    OpenAIRE

    Prasanta Sahoo; Suman Kalyan Das

    2012-01-01

    Electroless Ni-B coatings have found large applications due to their high hardness and wear resistance. The present paper tries to investigate the influence of coating process parameters on the microhardness of electroless Ni-B coating with the help of Taguchi analysis. Four parameters, namely, bath temperature, concentration of reducing agent, concentration of nickel source, and annealing temperature, are considered and fitted into an L27 orthogonal array to find out the optimized condition ...

  4. Tribological characterization of electroless NiP coatings lubricated with biolubricants

    OpenAIRE

    Ramalho, A; Miranda, J.C.

    2007-01-01

    Electroless nickel (EN) coatings are used in a wide range of applications concerning their excellent mechanical and tribological properties. The incorporation of solid lubricants, such as polytetrafluoroethylene (PTFE), could even improve the properties of the EN coatings. Above all, we can achieve a film with self-lubricating and excellent anti-sticking characteristics. These uses of electroless nickel coatings are widespread in dry contacts. However, it is well known that in the mechanical ...

  5. Electrochromism of the electroless deposited cuprous oxide films

    International Nuclear Information System (INIS)

    Thin cuprous oxide films were prepared by a low cost, chemical deposition (electroless) method onto glass substrates pre-coated with fluorine doped tin oxide. The X-ray diffraction pattern confirmed the Cu2O composition of the films. Visible transmittance spectra of the cuprous oxide films were studied for the as-prepared, colored and bleached films. The cyclic voltammetry study showed that those films exhibited cathode coloring electrochromism, i.e. the films showed change of color from yellowish to black upon application of an electric field. The transmittance across the films for laser light of 670 nm was found to change due to the voltage change for about 50%. The coloration memory of those films was also studied during 6 h, ex-situ. The coloration efficiency at 670 nm was calculated to be 37 cm2/C

  6. Electrochromism of the electroless deposited cuprous oxide films

    Energy Technology Data Exchange (ETDEWEB)

    Neskovska, R. [Faculty of Technical Sciences, University ' St. Clement Ohridski' , Bitola (Macedonia, The Former Yugoslav Republic of); Ristova, M. [Faculty of Natural Sciences and Mathematics, Institute of Physics, P.O. Box 162, Skopje (Macedonia, The Former Yugoslav Republic of)]. E-mail: mristova@iunona.pmf.ukim.edu.mk; Velevska, J. [Faculty of Natural Sciences and Mathematics, Institute of Physics, P.O. Box 162, Skopje (Macedonia, The Former Yugoslav Republic of); Ristov, M. [Macedonian Academy of Sciences and Arts, Skopje, Bul. Krste Misirkov bb, Skopje (Macedonia, The Former Yugoslav Republic of)

    2007-04-09

    Thin cuprous oxide films were prepared by a low cost, chemical deposition (electroless) method onto glass substrates pre-coated with fluorine doped tin oxide. The X-ray diffraction pattern confirmed the Cu{sub 2}O composition of the films. Visible transmittance spectra of the cuprous oxide films were studied for the as-prepared, colored and bleached films. The cyclic voltammetry study showed that those films exhibited cathode coloring electrochromism, i.e. the films showed change of color from yellowish to black upon application of an electric field. The transmittance across the films for laser light of 670 nm was found to change due to the voltage change for about 50%. The coloration memory of those films was also studied during 6 h, ex-situ. The coloration efficiency at 670 nm was calculated to be 37 cm{sup 2}/C.

  7. A novel preparation of silver-plated polyacrylonitrile fibers functionalized with antibacterial and electromagnetic shielding properties

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wei; Li, Weiya; Gao, Cuicui; Tian, Weicheng [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China); Sun, Bin [College of Material Science and Engineering, Donghua University, Shanghai 201620 (China); Yu, Dan, E-mail: yudan@dhu.edu.cn [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China)

    2015-07-01

    Highlights: • We propose a novel modification method to initiate silver electroless plating on PAN fiber without noble metal catalyst. • The silver-plated fiber we fabricated has good electromagnetic shielding effectiveness and antibacterial properties. • The metal layer has good adhesion strength and the properties of the silver-plated fiber can stand 30 cycles of standard washing. - Abstract: Polyacrylonitrile (PAN) fibers with antibacterial, electromagnetic shielding and antistatic functionalities were fabricated in this paper through modifying PAN fibers with (3-aminopropyl)triethoxysilane (APTES) and 3-mercaptopropyltriethoxysilane (MPTES) sequentially and followed with silver electroless plating. The silver layer on PAN fiber surface was characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM) and X-ray diffraction (XRD). The results show that the silver layer was plated uniformly and compactly. The surface resistance of plated fabric was about 40 mΩ/sq on average. The antibacterial tests demonstrate that silver-plated PAN fiber exhibits excellent antibacterial property against S. aureus and E. coli with a non-leaching characteristic. The antibacterial property remains good after 30 cycles of standard washing, which is a strong proof of a durable adhesion between metal layer and fiber. The shielding effectiveness (SE) of silver-plated PAN fabric before and after 30 cycles of standard washing was about 40–80 dB and 35–50 dB, respectively. This resultant fiber can be used in many occasions for reducing or preventing electromagnetic interference (EMI) and electromagnetic hazards.

  8. Improving copper plating adhesion on glass using laser machining techniques and areal surface texture parameters

    Science.gov (United States)

    He, Baofeng; Petzing, Jon; Webb, Patrick; Leach, Richard

    2015-12-01

    Glass is a promising substitute substrate material being evaluated for electronic packaging technology. Improving the electroless copper plated layer adhesion of the glass is one of the most important considerations for development of the technology. An excimer laser (248 nm) was used for structured texturing of glass surfaces (to improve adhesion) by changing mask dimensions, laser operating parameters and overlapping pitch spacing, and therefore producing a range of micro-scale features. Electroless plated copper adhesion strength was assessed using quantitative scratch testing, demonstrating that micro-patterned structures can significantly improve copper/glass adhesion. New ISO 25178 Part 2 areal surface texture parameters were used to characterise the surface roughness of ablated glass surfaces, and correlated to the scratch testing results. Highly correlated parameters were identified that could be used as predictive surface design tools, directly linking surface topography to adhesion performance, without the need for destructive adhesion quantification via scratch testing.

  9. Effect of Processing Parameters on the Protective Quality of Electroless Nickel-Phosphorus on Cast Aluminium Alloy

    Directory of Open Access Journals (Sweden)

    Olawale Olarewaju Ajibola

    2015-01-01

    Full Text Available The effects of temperature, pH, and time variations on the protective amount and quality of electroless nickel (EN deposition on cast aluminium alloy (CAA substrates were studied. The temperature, pH, and plating time were varied while the surface condition of the substrate was kept constant in acid or alkaline bath. Within solution pH of 5.0–5.5 range, the best quality is obtained in acid solution pH of 5.2. At lower pH (5.0–5.1, good adhesion characterised the EN deposition. Within the range of plating solution pH of 7.0 to 11.5, the highest quantity and quality of EN deposition are obtained on CAA substrate in solution pH of 10.5. It is characterised with few pores and discontinuous metallic EN film. The quantity of EN deposition is time dependent, whereas the adhesion and brightness are not time controlled. The best fit models were developed from the trends of result data obtained from the experiments. The surface morphologies and the chemical composition of the coating were studied using the Jeol JSM-7600F field emission scanning electron microscope.

  10. ELECTROLESS PLATING COMPOSITE COATINGS OF Ni-Ti-Re ON THE SURFACE OF DIAMOND

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Diamondtoolsaremadegeneralythroughthepowdermetalurgicalsinterproces.Itisobviousthattheinterfaceenergybetwenthediamondandord...

  11. Hydrofluoric Acid Corrosion Testing on Unplated and Electroless Gold-Plated Samples

    International Nuclear Information System (INIS)

    The Molten Salt Reactor Experiment (MSRE) remediation requires that almost 40 kg of uranium hexafluoride (UF6) be converted to uranium oxide (UO). In the process of this conversion, six moles of hydrofluoric acid (HP) are produced for each mole of UF6 converted

  12. Research of Kinetics of Electroless Ni-Cu-P Alloy Plating on Polyester Fabric

    Institute of Scientific and Technical Information of China (English)

    CHEN Zhen-bing; CHEN Xiao-li

    2002-01-01

    All the variables that may affect the Ni- Cu-P alloy deposition rate on polyester fabric were studied, and the activation energy and the reaction orders were determined. The deposition rate equation was also derived.

  13. Electroless Ni-P plating with a phytic acid pretreatment on AZ91D magnesium alloy

    International Nuclear Information System (INIS)

    A phytic acid conversion film with especial functional groups was proposed as the pretreatment layer between Ni-P coating and AZ91D magnesium alloy substrate, to replace the traditional pretreatment. In the process, the silane coupling agent was adopted as connector between conversion film and palladium ion with catalysis. The microstructure of the phytic acid conversion coatings was observed using scanning electronic microscopy, while the composition and functional groups were analyzed by energy dispersive spectrometer and Fourier transform infrared spectroscopy. The bonding between Si-OH of the silane coupling agent and hydroxyl of phytic acid was validated by X-ray photoelectron spectroscopy, and the existence of palladium ion was also verified. The subsequent Ni-P deposited on the layer was also characterized by its structure, morphology, and corrosion resistance. The results show that the Ni-P coatings with the phytic acid pretreatment on AZ91D magnesium alloy have good corrosion resistance.

  14. Electroless Ni-P plating with a phytic acid pretreatment on AZ91D magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Cui Xiufang, E-mail: cuixf97721@yahoo.com.cn [School of Materials Science and Chemical Engineering, Harbin Engineering University, 145 Nantong St., Harbin 150001 (China); State Key Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, 62 Wencui Road, Shenyang 110016 (China); Jin Guo; Li Qingfen; Yang Yuyun [School of Materials Science and Chemical Engineering, Harbin Engineering University, 145 Nantong St., Harbin 150001 (China); Li Ying [State Key Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, 62 Wencui Road, Shenyang 110016 (China); Wang Fuhui [School of Materials Science and Chemical Engineering, Harbin Engineering University, 145 Nantong St., Harbin 150001 (China); State Key Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, 62 Wencui Road, Shenyang 110016 (China)

    2010-05-15

    A phytic acid conversion film with especial functional groups was proposed as the pretreatment layer between Ni-P coating and AZ91D magnesium alloy substrate, to replace the traditional pretreatment. In the process, the silane coupling agent was adopted as connector between conversion film and palladium ion with catalysis. The microstructure of the phytic acid conversion coatings was observed using scanning electronic microscopy, while the composition and functional groups were analyzed by energy dispersive spectrometer and Fourier transform infrared spectroscopy. The bonding between Si-OH of the silane coupling agent and hydroxyl of phytic acid was validated by X-ray photoelectron spectroscopy, and the existence of palladium ion was also verified. The subsequent Ni-P deposited on the layer was also characterized by its structure, morphology, and corrosion resistance. The results show that the Ni-P coatings with the phytic acid pretreatment on AZ91D magnesium alloy have good corrosion resistance.

  15. Synergistic effect between nano-ceramic lubricating additives and electroless deposited Ni-W-P coating

    Science.gov (United States)

    Chen, Min; Cheng, Wushan; Zhao, Zuxin; Huang, Xiaobo

    2013-01-01

    The major solving ways for the material wear are surface modification and lubrication. Currently, the researches at home and abroad are all limited to the single study of either nano-lubricating oil additive or electroless deposited coating. The surface coating has high hardness and high wear resistance, however, the friction reduction performance of the coating with high hardness is not good, the thickness of the coating is limited, and the coating can not regenerate after wearing. The nano-lubricating additives have good tribological performance and self-repair function, but under heavy load, the self-repair rate to the worn surface with the nano-additives is smaller than the wearing rate of the friction pair. To solve the above problems, the Ni-W-P alloy coating and deposition process with excellent anti-wear, and suitable for industrial application were developed, the optimum bath composition and process can be obtained by studying the influence of the bath composition, temperature and PH value to the deposition rate and the plating solution stability. The tribological properties as well as anti-wear and friction reduction mechanism of wear self-repair nano-ceramic lubricating additives are also studied. The ring-block abrasion testing machine and energy dispersive spectrometer are used to explore the internal relation between the coating and the nano-lubricating oil additives, and the tribology mechanism, to seek the synergetic effect between the two. The test results show that the wear resistance of Ni-W-P alloy coating (with heat treatment and in oil with nano-ceramic additives) has increased hundreds times than 45 steel as the metal substrate in basic oil, the friction reduction performance is improved. This research breaks through the bottleneck of previous separate research of the above-mentioned two methods, and explores the combination use of the two methods in industrial field.

  16. Creating Complex Hollow Metal Geometries Using Additive Manufacturing and Metal Plating

    OpenAIRE

    McCarthy, David Lee

    2012-01-01

    Additive manufacturing introduces a new design paradigm that allows the fabrication of geometrically complex parts that cannot be produced by traditional manufacturing and assembly methods. Using a cellular heat exchanger as a motivational example, this thesis investigates the creation of a hybrid manufacturing approach that combines selective laser sintering with an electroforming process to produce complex, hollow, metal geometries. The developed process uses electroless nickel plating on l...

  17. Morphology Investigation of Electrolessly Deposited Ag Film on Ag-Activated p-Type Silicon(111) Wafer

    Institute of Scientific and Technical Information of China (English)

    TONG, Hao; WANG, Chun-Ming

    2006-01-01

    A method of electroless silver deposition on silver activated p-type silicon(111) wafer was proposed. The silver seed layer was deposited firstly on the wafer in the solution of 0.005 mol/L AgNO3 + 0.06 mol/L HF. Then the silver film was electrolessly deposited on the seed layer in the electroless bath of AgNO3+NH3+acetic acid+NH2NH2(pH 10.2). The morphology of the seed layer and the silver films prepared under the condition of the different bath composition was compared by atomic force microscopy. The reflectance of the silver films with different thickness was characterized by Fourier transform infrared spectrometry. The experimental results indicate that the seed layer possesses excellent catalytic activity toward electroless silver deposition and rotating of the silicon wafer during the electroless silver deposition could lead to formation of the smoother silver film.

  18. Electroless Ni-P-ferrite composite coatings for microwave applications

    Indian Academy of Sciences (India)

    Ramesh Chandra Agarwala

    2005-11-01

    Electroless, EL coating technique is one of the elegant ways of coating by controlling the temperature and pH of the coating bath in which there is no usage of electric current. It is estimated that the market for this chemistry will increase at a rate of about 15% per year. Use of microwave energy for synthesis of material with novel microstructures is an exciting new field in material science with enormous application. In this investigation, nanograined BaZn2-CoFe16O27 ( = 0.0, 0.4, 0.8, 1.2, 1.6 and 2.0) powders have been synthesized by citrate precursor method followed by heat treatment at various specified temperatures like 650, 750 and 850°C for 3 h in the furnace. In addition heat treatments are also carried out in the microwave oven of the power rating of 760 W. The powders thus produced have been characterized by SEM, EPMA, VSM, XRD and thermal analysis techniques. As a forward step towards EL nano-composite coatings, Ni-P- ( = BaZn2- CoFe16O27) coatings with thickness less than ∼ 0.1 mm thick has been produced. Such coating exhibits absorption of microwave in the range of 12-18 GHz up to about 20 db depending upon the volume fraction of the ferrite particles embedded in the Ni-P matrix.

  19. Investigation on a Non-cyanide Plating Process of Ni-P Coating on Magnesium Alloy AZ91D

    Institute of Scientific and Technical Information of China (English)

    Bonian HU; Gang YU; Jueling CHEN; Ying LI; Liyuan YE

    2005-01-01

    In this research we presented a non-cyanide plating process of Ni-P alloy coating on Mg alloy AZ91D. By applying a new process flow of electroless nickel plating in which zinc coating is used as transition of Ni-P coating on Mg alloy AZ91D, the process of copper transition coating plated in the cyanides bath can be replaced. A new bath composed of NiSO4 was established by orthogonal test. The results show that zinc transition coating can increase the adhesion and pH 4.0 and 95℃, respectively. The present process flow is composed of ultrasonic cleaning→alkaline cleaning→acid pickling→activation→double immersing zinc→electroplating zinc→electroless nickel plating→passivation treatment.The present non-cyanide process of electroless nickel plating is harmless to our surroundings and Ni-P coating on Mg alloy AZ91D produced by present process possesses good adhesion and corrosion resistance.

  20. Electrochemical Characteristics of Titanium for Dental Implants in Case of the Electroless Surface Modification

    Directory of Open Access Journals (Sweden)

    Klimecka-Tatar D.

    2016-06-01

    Full Text Available In the paper the results of research under effect of electroless phosphate coating of titanium dental implants on potentiokinetic polarization characteristic obtained in artificial saliva were presented. On the basis of electrochemical studies it was concluded that the electroless process of phosphating beneficialy effect on corrosion characteristic of titanium determined in solution simulating the oral cavity. Furthermore, the proposed technique of chemical treatment of titanium surface is conducive to the homogeneous development of the surface, which is extremely important from the point of view of titanium implants biointegration. Phosphating treatment affect on the development of surface geometry, resulting in a slight increase in roughness parameters (Ra, Rz and Rmax. The temperature increase of electroless phosphating treatment promotes the rate of conversion layer formation, whereas the effect of temperature of the chemical treatment efficiency is secondary important at longer exposure times (e.g. 45 minutes.

  1. Synthesis and characterization of nanocrystalline silver coating of fly ash cenosphere particles by electroless process.

    Science.gov (United States)

    Shukla, S; Seal, S; Schwarz, S; Zhou, D

    2001-12-01

    Electroless nanocrystalline Ag coating of fly ash cenosphere particles utilizing a Sn-Pd catalyst system is demonstrated in this article. The deposition of pure metallic nanocrystalline Ag on the fly ash cenosphere particle surface is confirmed by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) analysis. Under the described conditions of electroless coating, average nanocrystalline Ag-coating thickness is observed to be approximately 220 nm, using a focused ion beam technique, which is less than that observed by transmission electron microscopy (TEM) (260-360 nm). TEM observation further reveals that the Ag-coating is made up of 50 nm Ag nanocrystallites, which is comparable with the size of approximately 37 nm obtained from the XRD data. The mechanism of the electroless Ag-coating process is discussed. Ag-coated fly ash particles find applications in manufacturing conducting polymers for electromagnetic interference shielding applications. PMID:12914083

  2. PREPARATION AND ANALYSIS OF Ni-P-Zn ELECTROLESS DEPOSITION FROM ALKALT BATH

    Institute of Scientific and Technical Information of China (English)

    Y.S. Huang; F.Z. Cui

    2005-01-01

    Electroless Ni-P-Zn alloys deposited from alkali bath were investigated in this paper. The deposition bath contained nickel sulfate, zinc chloride and hypophosphate. The process parameters, such as temperature, pH and zinc salt concentration were presented and discussed.The microstructure of the coatings was studied by XRD and SEM. The cathode glowing discharge characters of Ni-P-Zn depositions were studied with luminous Neon lamps. Electrodes deposited by electroless Ni-P alloys were apt to sputter during luminous working hours. Electroless Ni-P-Zn depositions improved the discharge characters of the electrodes.With the concentration of zinc in the deposition rising to 4wt%, electrode sputter was largely restrained. The thickness of the deposition also influenced the discharge characters of the electrode. To avoid electrode sputter, the concentration of zinc has to rise with the thickness of the depositions.

  3. Electroless Ni-Co-P Coating of Cenospheres Using Ag(NH3)2+ Activator

    Institute of Scientific and Technical Information of China (English)

    ZENG Ai-xiang; XIONG Wei-hao

    2004-01-01

    Electroless Ni-Co-P-coating of fly-ash cenosphere particles is demonstrated in the present investigation. The Electroless Ni-Co-P-coating process is modified by replacing the conventional sensitization and activation steps with only using activation step with Ag(NH3)2+ activator. The cenospheres are characterized by scanning electron microscope (SEM),energy dispersive spectroscopy (EDX), X-ray diffraction analysis (XRD) and X-ray photoelectron spectroscopy (XPS)during and after the coating process. Relatively uniform coating is obtained under the given coating conditions. The possible mechanism of electroless Ni-Co-P-coating of cenospheres utilizing Ag(NH3)2+ activator is suggested. The low density Ni-Co-P coated cenospheres may be utilized for manufacturing conducting polymers for EMI-shielding application and microwave absorbing materials.

  4. Electroless deposition, post annealing and characterization of nickel films on silicon

    Indian Academy of Sciences (India)

    Subir Sabharwal; Siddharth Palit; R B Tokas; A K Poswal; Sangeeta

    2008-10-01

    Electroless deposition of nickel (EN) films on -type silicon has been investigated under different process conditions. The interface between the film and substrate has been characterized for electrical properties by probing the contact resistances. X-ray diffraction and atomic force microscopy have been performed to obtain information about the structural and morphological details of the films. As a comparative study, nickel films have also been sputter deposited on silicon substrates. An as-deposited electroless film is observed to form non-ohmic contact while in a sputtered film prepared without the application of substrate heating, the formation of metal–insulating–semiconductor type junction is seen.

  5. MONTE-CARLO SIMULATION FOR ATOMIC DEPOSITION OF AMORPHOUS ELECTROLESS Ni80P20 COATING

    Institute of Scientific and Technical Information of China (English)

    K.S. Guan; H.R. Bai; Z.W. Wang; Y.S. Yin

    2002-01-01

    Atomic growth process and structure of Amorphous Electroless Coating have beenstudied, using Monte-Carlo simulation method. The simulation results of amorphousNi80P20 coating show that PDFs are in accordance with practical values. The mi-grations of adatoms in coating's growth are different from that of solidification ofamorphous materials. In some cases, the migrated adatoms in the process of growthof amorphous coating are not enough to occupy all vacancies and traps, so the amor-phous coating is micro-porous. The immovable probability k and the largest migrationdistance of adatoms, which lie on the electroless bath components, affect the PDF,volume density and microporosity remarkably.

  6. Conductive ceramic coating on polyacrylonitrile-vinyl chloride (modacrylic) discontinuous fibers via electroless deposition

    Energy Technology Data Exchange (ETDEWEB)

    Patankar, S.N. [Department of Materials Science and Engineering, University of Idaho, ID 83844-3024 (United States); McAllister, S.D.; Cheng, I. Francis [Department of Chemistry, University of Idaho, ID 83844-2343 (United States); Edwards, D.B. [Department of Chemical Engineering, University of Idaho, ID 83844-1024 (United States)

    2010-01-01

    Lead dioxide has electrical conductivity that is comparable to that of some of the metals. As a result like copper and nickel, lead dioxide can be deposited on non-conducting materials like polymers and ceramics using spontaneous and low cost deposition technique such as electroless deposition. This paper deals with development of conductive modacrylic fibers by coating them with lead dioxide via electroless deposition. The fibers so obtained will be used as additive in the lead-acid battery to improve its life and specific energy. (author)

  7. The Effect and Mechanism of Nano-Cu Lubricating Additives on the Electroless Deposited Ni-W-P Coating

    Institute of Scientific and Technical Information of China (English)

    CHEN Min; JIANG Xiaomin; ZHAO Zuxin; HUANG Xiaobo

    2012-01-01

    The coating and deposition process with excellent anti wear and suitable for industrial application were developed,and the optimum bath composition and process were obtained by studying the influence of the bath composition,temperature and pH value on the deposition rate and the plating solution stability.Moreover,the tribological properties of nano-Cu lubricating additives and electroless deposited Ni-W-P coating as well as their synergistic effect are researched using ring-block abrasion testing machine and energy dispersive spectrometer.Research results show that Ni-W-P alloy coating and nano-Cu lubricating additive have excellent synergistic effect,e g,the wear resistance of Ni-W-P alloy coating (with heat treatment and the oil with nano-Cu additives) has increased hundreds times than 45 steel as the metal substrate with the basic oil,and zero wear is achieved,which breaks through the bottleneck of previous separate research of the above-mentioned two aspects.

  8. Salt Spray Test to Determine Galvanic Corrosion Levels of Electroless Nickel Connectors Mounted on an Aluminum Bracket

    Science.gov (United States)

    Rolin, T. D.; Hodge, R. E.; Torres, P. D.; Jones, D. D.; Laird, K. R.

    2014-01-01

    During preliminary vehicle design reviews, requests were made to change flight termination systems from an electroless nickel (EN) connector coating to a zinc-nickel (ZN) plating. The reason for these changes was due to a new NASA-STD-6012 corrosion requirement where connectors must meet the performance requirement of 168 hr of exposure to salt spray. The specification for class F connectors, MIL-DTL-38999, certifies the EN coating will meet a 48-hr salt spray test, whereas the ZN is certified to meet a 168-hr salt spray test. The ZN finish is a concern because Marshall Space Flight Center has no flight experience with ZN-finished connectors, and MSFC-STD-3012 indicates that zinc and zinc alloys should not be used. The purpose of this test was to run a 168-hr salt spray test to verify the electrical and mechanical integrity of the EN connectors and officially document the results. The salt spray test was conducted per ASTM B117 on several MIL-DTL-38999 flight-like connectors mounted to an aluminum 6061-T6 bracket that was alodined. The configuration, mounting techniques, electrical checks, and materials used were typical of flight and ground support equipment.

  9. The Microstructure of Ni Layer on Single-Walled Carbon Nanotubes Prepared by an Electroless Coating Process

    Directory of Open Access Journals (Sweden)

    Weixue Li

    2011-01-01

    Full Text Available The single-walled carbon nanotubes (SWNTs, diameter: 2~3 nm, which were obtained in the suspension of purification solution, with Ni-P coating layers were obtained by an electroless deposition process. The SWNTs before and after coating were characterized by transmission electron microscopy (TEM and energy dispersive spectrometry (EDS. An Ni-P layer on individual nanotube with thickness of 20 nm can be obtained after the deposition process. The X-ray diffraction (XRD and selected area electron diffraction (SAED analysis of Ni-P SWNTs before and after heat treatment show that the heat treatment caused the transformation of the amorphous Ni-P layer to the nanocrystalline Ni-P (crystalline Ni and Ni3P intermetallic compound layer. The XRD pattern of SWNTs with Ni-P layers after heat treatment revealed that the crystal structures of Ni in plating layer contained: hexagonal close-packed (hcp structure and face-centered cubic (fcc structure. The lattice parameters of Ni (fcc and Ni3P are larger than the bulk's, indicting that the lattice expansion has taken place. However, the lattice parameter of Ni (hcp has no difference from the bulk's.

  10. Effect of Addition of Polytetrafluoroethylene (PTFE) and Silicon Carbide (SiC) on Properties of Electroless Nickel Alloy Coatings

    Institute of Scientific and Technical Information of China (English)

    WU Yu-cheng; HU Xiao-ye; WANG Wen-fang; HUANG Xin-min

    2004-01-01

    Electroless nickel (copper)-phosphorus-silicon carbide (SiC)-polytetrafluoroethylene (PTFE) composite coatings were prepared by adding SiC and PTFE into electroless nickel (copper)-phosphorus alloy baths. The effects of addition of SiC and PTFE on depositing rate, microhardness, wear resistance and anti-friction of the resulted composite coatings were studied. The results indicated that electroless nickel (copper)-phosphorus alloy coatings were greatly improved in depositing rate, microhardness, wear resistance and antifriction by co-deposited proper amount of SiC and PTFE.

  11. Effects of Pretreatment on the Structure And Properties of Electroless Nickel Coatings

    DEFF Research Database (Denmark)

    Møller, Per; Deng, Hong

    1994-01-01

    The pretreatment process can significantly affect the corrosion resistance of electroless nickel (EN) coatings One of the most important reasons is that different pretreatment processes can give different surface morphologies of the substrate. The scanning electron microscope (SEM) and the scanning...

  12. Controlled Ag electroless deposition in bulk structures with complex three-dimensional profiles

    DEFF Research Database (Denmark)

    Malureanu, Radu; Zalkovskij, Maksim; Andryieuski, Andrei;

    2010-01-01

    are of high uniformity, having an average roughness of about 4 nm. The characterization of the metal deposition is done using both the scanning electron microscopy technique as well as by atomic force microscope measurements. The electroless technique can be easily implemented, providing the effective...

  13. Effect of Rare Earth Metals on Structure and Properties of Electroless Co-B Alloy Coating

    Institute of Scientific and Technical Information of China (English)

    宣天鹏; 张雷; 黄秋华

    2002-01-01

    The effect of rare earth metals cerium, lanthanum and yttrium on chemical composition, structure and properties of electroless Co-B alloy coating was studied. By plasma transmitting spectrograph, electron energy spectrometer, X-ray diffractometter, micro-hardometer and vibratory sample magnetometer the chemical constitution, structure and properties of the alloy coatings were analyzed and inspected. The results show that with a tiny quantity of rare earth metal added into Co-B alloy coating, the content of boron is decreased in the alloy coatings, and the kinds of rare earth metal have enormous effect on the structure and properties of electroless Co-B alloy coating. At the same time electroless Co-B alloy with amorphous structure is transformed to electroless Co-B-RE alloy with microcrystalline or crystalline structure. In this way microhardness of the coatings is increased remarkably. Cerium and lanthanum would also increase the saturated magnetic intensity and decrease coercitive force of the coating. So soft magnetization of the coatings would be improved.

  14. A novel electroless method to prepare a platinum electrocatalyst on diamond for fuel cell applications

    Science.gov (United States)

    Lyu, Xiao; Hu, Jingping; Foord, John S.; Wang, Qiang

    2013-11-01

    A novel electroless deposition method was demonstrated to prepare a platinum electrocatalyst on boron doped diamond (BDD) substrates without the need for pre-activation. This green method addresses the uniformity and particle size issues associated with electrodeposition and circumvents the pre-activation procedure which is necessary for conventional electroless deposition. The inert BDD substrate formed a galvanic couple with an iron wire, to overcome the activation barrier associated with conventional electroless deposition on diamond, leading to the formation of Pt nanoparticles on the electrode surface in a galvanic process coupled to a chemical process. When sodium hypophosphite was employed as the reducing agent to drive the electroless reaction Pt deposits which were contaminated with iron and phosphorus resulted. In contrast, the reducing agent ascorbic acid gave rise to high purity Pt nanoparticles. Optimal deposition conditions with respect to bath temperature, pH value and stabilizing additives are identified. Using this approach, high purity and uniformly distributed platinum nanoparticles are obtained on the diamond electrode surface, which demonstrate a high electrochemical activity towards methanol oxidation.

  15. Platinum-ruthenium bimetallic clusters on graphite: a comparison of vapor deposition and electroless deposition methods.

    Science.gov (United States)

    Galhenage, Randima P; Xie, Kangmin; Diao, Weijian; Tengco, John Meynard M; Seuser, Grant S; Monnier, John R; Chen, Donna A

    2015-11-14

    Bimetallic Pt-Ru clusters have been grown on highly ordered pyrolytic graphite (HOPG) surfaces by vapor deposition and by electroless deposition. These studies help to bridge the material gap between well-characterized vapor deposited clusters and electrolessly deposited clusters, which are better suited for industrial catalyst preparation. In the vapor deposition experiments, bimetallic clusters were formed by the sequential deposition of Pt on Ru or Ru on Pt. Seed clusters of the first metal were grown on HOPG surfaces that were sputtered with Ar(+) to introduce defects, which act as nucleation sites for Pt or Ru. On the unmodified HOPG surface, both Pt and Ru clusters preferentially nucleated at the step edges, whereas on the sputtered surface, clusters with relatively uniform sizes and spatial distributions were formed. Low energy ion scattering experiments showed that the surface compositions of the bimetallic clusters are Pt-rich, regardless of the order of deposition, indicating that the interdiffusion of metals within the clusters is facile at room temperature. Bimetallic clusters on sputtered HOPG were prepared by the electroless deposition of Pt on Ru seed clusters from a Pt(+2) solution using dimethylamine borane as the reducing agent at pH 11 and 40 °C. After exposure to the electroless deposition bath, Pt was selectively deposited on Ru, as demonstrated by the detection of Pt on the surface by XPS, and the increase in the average cluster height without an increase in the number of clusters, indicating that Pt atoms are incorporated into the Ru seed clusters. Electroless deposition of Ru on Pt seed clusters was also achieved, but it should be noted that this deposition method is extremely sensitive to the presence of other metal ions in solution that have a higher reduction potential than the metal ion targeted for deposition. PMID:26018140

  16. Minimizing the bimetallic bending for cryogenic metal optics based on electroless nickel

    Science.gov (United States)

    Kinast, Jan; Hilpert, Enrico; Lange, Nicolas; Gebhardt, Andreas; Rohloff, Ralf-Rainer; Risse, Stefan; Eberhardt, Ramona; Tünnermann, Andreas

    2014-07-01

    Ultra-precise metal optics are key components of sophisticated scientific instruments in astronomy and space applications. Especially for cryogenic applications, a detailed knowledge and the control of the coefficient of thermal expansion (CTE) of the used materials are essential. Reflective optical components in IR- and NIR-instruments primarily consist of the aluminum alloy Al6061. The achievable micro-roughness of diamond machined and directly polished Al6061 does not fulfill the requirements for applications in the visible spectral range. Electroless nickel enables the reduction of the mirror surface roughness to the sub-nm range by polishing. To minimize the associated disadvantageous bimetallic effect, a novel material combination for cryogenic mirrors based on electroless nickel and hypereutectic aluminum-silicon is investigated. An increasing silicon content of the aluminum material decreases the CTE in the temperature range to be considered. This paper shows the CTE for aluminum materials containing about 42 wt% silicon (AlSi42) and for electroless nickel with a phosphorous content ranging from 10.5 to 13 %. The CTE differ to about 0.5 × 10-6 K-1 in a temperature range from -185 °C (LN2) to 100 °C. Besides, the correlations between the chemical compositions of aluminum-silicon materials and electroless nickel are shown. A metrology setup for cryo-interferometry was developed to analyze the remaining and reversible shape deviation at cryogenic temperatures. Changes could be caused by different CTE, mounting forces and residual stress conditions. In the electroless nickel layer, the resulting shape deviation can be preshaped by deterministic correction processes such as magnetorheological finishing (MRF) at room temperature.

  17. Ni-P化学镀层表面实现滴状冷凝传热%Dropwise condensation on the surface of Ni-P electroless coating

    Institute of Scientific and Technical Information of China (English)

    曾斌; 侯峰; 徐宏; 阮艺平

    2012-01-01

    In order to achieve the surface preparation techniques that promoted the formation of dropwise condensation heat transfer,Ni-P coating on carbon steel by electroless plating,and its condensation heat transfer performance were studied.The results showed that complete dropwise condensation was achieved on the surface of Ni-P electroless coating,the heat flux and heat transfer coefficient was 3 to 5 times higher than the values calculated by Nusselt film theory.Meantime,it was found that the amorphous of coating was the main reason for promoting the formation of dropwise condensation heat transfer.The co-existence state of dropwise and filmwise was obtained when the coating was crystallized by heat treatment.%为了探索能实现滴状冷凝传热的表面制备技术,采用化学镀技术在碳钢表面制备非晶态Ni-P化学镀层,对其冷凝传热性能进行了实验研究。结果表明,Ni-P化学镀层表面常压水蒸气下实现了完全的滴状冷凝传热,表面热通量和传热系数均比膜状冷凝Nusselt理论计算结果提高了3~5倍。同时发现,镀层的非晶态是实现滴状冷凝传热形态的主要原因,经过热处理晶化后,表面形成的是滴膜共存的冷凝传热形态,冷凝传热强化效果显著降低。

  18. Microstructural and mechanical characterizations of a novel HVOF-sprayed WC-Co coating deposited from electroless Ni–P coated WC-12Co powders

    Energy Technology Data Exchange (ETDEWEB)

    Jafari, M., E-mail: majid_jafari@ma.iut.ac.ir [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Iranian Surface Research and Engineering Centre, Isfahan 84155-337 (Iran, Islamic Republic of); Enayati, M.H.; Salehi, M. [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Iranian Surface Research and Engineering Centre, Isfahan 84155-337 (Iran, Islamic Republic of); Nahvi, S.M. [Iranian Surface Research and Engineering Centre, Isfahan 84155-337 (Iran, Islamic Republic of); Park, C.G. [Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784 (Korea, Republic of)

    2013-08-20

    In this research, a novel WC-Co coating was deposited from electroless Ni–P coated WC-12Co powders using high velocity oxygen fuel (HVOF) process. Toward this purpose, an electroless Ni–P plating process was used to develop a uniform Ni–P layer on the surface of WC-12Co powders. The obtained Ni–P coated powders were then used as HVOF feedstock material. Microstructural characteristics of the Ni–P coated WC-12Co powders and the resultant coating, which is denoted as Ni–P modified coating, were investigated using X-ray diffractometry (XRD) and high resolution field emission scanning electron microscopy (HR FE SEM). The micro-hardness, elastic modulus and fracture toughness measurements were executed to evaluate the mechanical properties of the Ni–P modified coating. For comparison, the same experiments were performed on two conventional HVOF sprayed WC-12Co and WC-17Co coatings. The Ni–P modified WC-12Co coating showed a dense structure with extremely low porosity of ∼0.3% which was much lower than that of WC-12Co and WC-17Co coatings. Besides, it was observed that the Ni–P modified coating has undergone negligible decarburization of 2.6% as compared to conventional WC-12Co and WC-17Co coatings with that of 16.3 and 17.6%. The Ni–P modified coating showed the maximum hardness of ∼11.45 GPa, while lower hardness values of 10.98 and 10.59 GPa were measured for the WC-12Co and WC-17Co coatings. The fracture toughness of Ni–P modified WC-12Co coating was found to be 9.86 MPa m{sup 1/2}, indicating 71.2 and 61.1% increase in comparison with WC-12Co and WC-17Co coatings, respectively.

  19. INTEGRATED USE OF RAPID PROTOTYPING AND METAL PLATING TECHNIQUES FOR DEVELOPMENT OF MICRO AIR VEHICLES

    Directory of Open Access Journals (Sweden)

    Dr. K. ELANGOVAN,

    2011-01-01

    Full Text Available This paper describes the synergistic application of rapid prototyping and metal plating technologies for development of micro air vehicles (MAV with high strength-to-weight characteristic. Stereolithography and fused deposition techniques are employed to fabricate complex thermoplastic MAV prototypes with significant time-compression in production cycle. Electroless and electrolytic deposition processes are custom developed to deposit thin metallic foils of nickel and chromium over thermoplastic MAV prototypes. Plating plant with inherent provision for variation of process parameters is established and proof-of-concept studies are carried on plating of MAV prototypes. Experiments are conducted on metal plated thermoplastic test specimens for evaluating the mechanical behaviour and structural integrity properties. Present study is a conclusive demonstration of the use of layered manufacturing techniques in quick realisation of flight-worthy MAV systems.

  20. Effect of Nanoadditives with Surfactant on the Surface Characteristics of Electroless Nickel Coating on Magnesium-Based Composites Reinforced with MWCNT

    OpenAIRE

    Ranganathan Dhinakaran; Rasu Elansezhian; Arunachalam Arumugam Lalitha

    2013-01-01

    An experimental investigation has been carried out on optimizing process parameters of electroless nickel-phosphorous coatings on magnesium composite reinforced with carbon nanotube. A comprehensive experimental study of electroless Ni–P coatings on magnesium composite reinforced with multiwalled carbon nanotube under specific coating conditions was performed. The electroless coating bath consists of nickel sulphate (26 g/L), sodium hypo-phosphite (30 g/L) as reducing agent, sodium acetate (1...

  1. Fabrication of cube textured Au/Ni template using electoless-plating

    International Nuclear Information System (INIS)

    We fabricated the Au/Ni template for YBCO coated conductors and evaluated texture formation and the microstructural evolution. The cube textured Ni substrate was fabricated by rolling and recrystallization annealing, and subsequently Au layer formed on the substrate by electroless-plating method. The texture was evaluated by pole-figure with x-ray goniometer with orientation distribution function (ODF) analysis. The surface roughness and grain boundary morphology of template were characterized by atomic force microscopy (AFM). We observed that Au layer deposited epitaxially on Ni substrate and formed a strong cube texture when plating time was optimized. The full-width at half-maximum (FWHM) was 8.4 degree for out-of-plane and 9.98 degree for in-plane texture for plating time of 30 min. Microstructural observation showed that the Au layer was homogeneous and dense without formation of crack/microcrack. In addition, we observed that root-mean-square (RMS) and depth of grain boundary were 14.6 nm and 160 for the Au layer, respectively, while those were 27.0 nm and 800 for the Ni substrate, indicating that the electroless-plated Au layer had relatively smooth surface and effectively mollified grain groove.

  2. Synthesis of dense nano cobalt-hydroxyapatite by modified electroless deposition technique

    Science.gov (United States)

    Mohd Zaheruddin, K.; Rahmat, A.; Shamsul, J. B.; Mohd Nazree, B. D.; Aimi Noorliyana, H.

    2016-07-01

    Cobalt-hydroxyapatite (Co-HA) composites was successfully prepared by simple electroless deposition process of Co on the surface of hydroxyapatite (HA) particles. Co deposition was carried out in an alkaline bath with sodium hypophosphite as a reducing agent. The electroless process was carried out without sensitization and activation steps. The deposition of Co onto HA was characterized by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The Co-HA composite powder was compacted and sintered at 1250°C. The Co particles were homogeneously dispersed in the HA matrix after sintering and the mechanical properties of composites was enhanced to 100 % with 3 % wt Co and gradually decreased at higher Co content.

  3. Surface-grafted polymer-assisted electroless deposition of metals for flexible and stretchable electronics.

    Science.gov (United States)

    Liu, Xuqing; Zhou, Xuechang; Li, Yi; Zheng, Zijian

    2012-05-01

    Surface-grafted polymers, that is, ultrathin layers of polymer coating covalently tethered to a surface, can serve as a particularly promising nanoplatform for electroless deposition (ELD) of metal thin films and patterned structures. Such polymers consist of a large number of well-defined binding sites for highly efficient and selective uptake of ELD catalysts. Moreover, the polymer chains provide flexible 3D network structures to trap the electrolessly deposited metal particles, leading to strong metal-substrate adhesion. In the past decade, surface-grafted polymers have been demonstrated as efficient nanoplatforms for fabricating durable and high-performance metal coatings by ELD on plastic substrates for applications in flexible and stretchable electronics. This focus review summarizes these recent advances, with a particular focus on applications in polymeric flexible and stretchable substrates. An outlook on the future challenges and opportunities in this field is given at the end of this paper. PMID:22392811

  4. Laser surface heat treatment of electroless Ni-P-SiC coating on Al356 alloy

    Science.gov (United States)

    Hashemi, Sayed Hamid; Shoja-Razavi, Reza

    2016-11-01

    Electroless Ni-P-SiC coatings are recognized for their hardness and wear resistance. In the present study, electroless Ni-P coatings containing SiC particles were co-deposited on Al356 substrate. Laser surface heat treatment was performed using 700 W Nd:YAG pulsed laser. Effects of different laser operating parameters, such as laser scan rate, laser average power and defocusing distance on microstructures were investigated by optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive spectrometer (EDS). The results of microstructural characterization indicated that the laser treatment under different operating conditions produced composite coating contained nanocrystallined Ni-based matrix with SiC particles Ni3P, Ni12P5, Ni5P2, Ni8P3 precipitates. The microhardness measurements showed that the hardness of the coating was increased up to 60%, due to laser heat treatment, without effect on base metal.

  5. Room temperature synthesis of indium tin oxide nanotubes with high precision wall thickness by electroless deposition

    Directory of Open Access Journals (Sweden)

    Mario Boehme

    2011-02-01

    Full Text Available Conductive nanotubes consisting of indium tin oxide (ITO were fabricated by electroless deposition using ion track etched polycarbonate templates. To produce nanotubes (NTs with thin walls and small surface roughness, the tubes were generated by a multi-step procedure under aqueous conditions. The approach reported below yields open end nanotubes with well defined outer diameter and wall thickness. In the past, zinc oxide films were mostly preferred and were synthesized using electroless deposition based on aqueous solutions. All these methods previously developed, are not adaptable in the case of ITO nanotubes, even with modifications. In the present work, therefore, we investigated the necessary conditions for the growth of ITO-NTs to achieve a wall thickness of around 10 nm. In addition, the effects of pH and reductive concentrations for the formation of ITO-NTs are also discussed.

  6. Room temperature synthesis of indium tin oxide nanotubes with high precision wall thickness by electroless deposition.

    Science.gov (United States)

    Boehme, Mario; Ionescu, Emanuel; Fu, Ganhua; Ensinger, Wolfgang

    2011-01-01

    Conductive nanotubes consisting of indium tin oxide (ITO) were fabricated by electroless deposition using ion track etched polycarbonate templates. To produce nanotubes (NTs) with thin walls and small surface roughness, the tubes were generated by a multi-step procedure under aqueous conditions. The approach reported below yields open end nanotubes with well defined outer diameter and wall thickness. In the past, zinc oxide films were mostly preferred and were synthesized using electroless deposition based on aqueous solutions. All these methods previously developed, are not adaptable in the case of ITO nanotubes, even with modifications. In the present work, therefore, we investigated the necessary conditions for the growth of ITO-NTs to achieve a wall thickness of around 10 nm. In addition, the effects of pH and reductive concentrations for the formation of ITO-NTs are also discussed.

  7. Electroless Gold-Modified Diatoms as Surface-Enhanced Raman Scattering Supports

    Science.gov (United States)

    Pannico, Marianna; Rea, Ilaria; Chandrasekaran, Soundarrajan; Musto, Pellegrino; Voelcker, Nicolas H.; De Stefano, Luca

    2016-06-01

    Porous biosilica from diatom frustules is well known for its peculiar optical and mechanical properties. In this work, gold-coated diatom frustules are used as low-cost, ready available, functional support for surface-enhanced Raman scattering. Due to the morphology of the nanostructured surface and the smoothness of gold deposition via an electroless process, an enhancement factor for the p-mercaptoaniline Raman signal of the order of 105 is obtained.

  8. Tribological Performance Optimization of Electroless Ni-P-W Coating Using Weighted Principal Component Analysis

    OpenAIRE

    Roy, S.; Sahoo, P.

    2013-01-01

    The present investigation is an experimental approach to deposit electroless Ni-P-W coating on mild steel substrate and find out the optimum combination of various tribological performances on the basis of minimum friction and wear, using weighted principal component analysis (WPCA). In this study three main tribological parameters are chosen viz. load (A), speed (B) and time(C). The responses are coefficient of friction and wear depth. Here Weighted Principal Component Analysis (WPCA) method...

  9. EVALUATION OF THE PERFORMANCE OF ELECTROLESS Ni–B COATED BRASS CONTACTS UNDER FRETTING CONDITIONS

    OpenAIRE

    T.S.N. Sankara Narayanan; YOUNG WOO PARK; KANG YONG LEE

    2008-01-01

    The performance of electroless (EL) Ni–B coated brass contacts under fretting conditions was evaluated. The contact resistance of EL Ni–B coated brass contact was measured as a function of fretting cycles. The surface profile and wear depth of the fretted zone were measured using laser scanning microscope. The study reveals that EL Ni–B coated contacts exhibit better performance under fretting conditions. However, at conditions which are prone for severe oxidation such as, low frequency (3 Hz...

  10. Pure-Nickel-Coated Multiwalled Carbon Nanotubes Prepared by Electroless Deposition

    OpenAIRE

    Arai, Susumu; Kobayashi, Mitsuhiro; Yamamoto, Tohru; Endo, Morinobu

    2010-01-01

    Pure-nickel-coated multiwalled carbon nanotubes (MWCNTs) have been prepared by electroless deposition. Gluconic acid and hydrazine were respectively used as the complexing and reducing agents for nickel ions. The deposits were heat-treated. The microstructures and magnetic properties of the deposits were examined. The MWCNTs were homogeneously coated with pure nickel and their surfaces were relatively bumpy. These pure-nickel-coated MWCNTs exhibited ferromagnetism and had higher magnetization...

  11. Electroless Gold-Modified Diatoms as Surface-Enhanced Raman Scattering Supports.

    Science.gov (United States)

    Pannico, Marianna; Rea, Ilaria; Chandrasekaran, Soundarrajan; Musto, Pellegrino; Voelcker, Nicolas H; De Stefano, Luca

    2016-12-01

    Porous biosilica from diatom frustules is well known for its peculiar optical and mechanical properties. In this work, gold-coated diatom frustules are used as low-cost, ready available, functional support for surface-enhanced Raman scattering. Due to the morphology of the nanostructured surface and the smoothness of gold deposition via an electroless process, an enhancement factor for the p-mercaptoaniline Raman signal of the order of 10(5) is obtained. PMID:27356562

  12. Fabrication of antibacterial and hydrophilic electroless Ni-B coating on 316L stainless steel

    Science.gov (United States)

    Bülbül, Ferhat; Bülbül, Leman Elif

    2016-01-01

    Biomaterial-associated bacterial infection is one of the most common complications with medical vehicles and implants made of stainless steel. A surface coating treatment like electroless Ni-B deposition, a new candidate to be used in a broad range of engineering applications owing to many advantages such as low cost, thickness uniformity, good wear resistance, may improve the antibacterial activity and physical properties of biomedical devices made of stainless steel. In this study, the antibacterial property of the electroless Ni-B film coated on AISI 316L (UNS S31603) stainless steel is basically investigated. Inhibition halo diameter measurement after incubation at 37 °C and 24 h demonstrates the existence of antimicrobial activity of the electroless Ni-B coating deposited on 316L stainless steel over the Escherichia coli test bacteria. The results of X-ray diffraction, scanning electron microscopy, atomic force microscopy and microhardness measurement studies confirms that the coating deposited on the substrate has an uniform amorphous and a harder structure. Besides, the wettability property of the uncoated substrate and the coating was measured as the contact angle of water. The water contact angle reduced about from 97.7 to 69.25°.

  13. Surface texturing for adaptive Ag/MoS_2 solid lubricant plating

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    The objective of this research is to prepare specially designed surface texture on hard steel surface by electrochemical micromachining (EM) and to incorporate electroless plated Ag/MoS2 solid lubricant coating into the dimples of EM textured steel surface to effectively reduce friction and wear of steel-steel contacts. The friction and wear behavior of the Ag/MoS2 solid lubricant coating on EM textured steel surface was evaluated in relation to the size and spacing of the dimples thereon. The microstructur...

  14. Controllable Silver Plating on Silica for Surface-enhanced Raman Scattering

    Institute of Scientific and Technical Information of China (English)

    CHEN Lei; HAN Xiao-xia; YANG Jing-xiu; ZHOU Ji; LU Zhi-cheng; SONG Wei; ZHAO Bing; XU Wei-qing; OZAKI Yukihiro

    2011-01-01

    We proposed a facile and rapid method for preparing silica-silver core-shell(SSCS) substrates to use Ag electroless plating on SiO2@Au-seed particles.UV-Vis-NIR absorption spectrometer and SEM were employed to monitor the reaction process of the formation of Ag on the surfaces of silica beads,and the optical resonance of the substrate could shift from visible to NIR region.It has been found that surface-enhanced Raman scattering(SERS)enhancement changes with the electroless plating time and the SSCS substrate with the plating time of 90 s(90SSCS)shows the strongest SERS response under the laser excitation at 514.5 nm.Signals collected over multiple spots and substrate of rhodamine 6G(R6G) resulted in a relative standard deviation(RSD) of 9.75%.The calculated enhancement factor(EF) was approximately 105-106.SSCS substrate exhibits high SERS performance,which is due to electromagnetic SERS enhancement with additional localization field within closely packed Ag nanoparticles decorated on the SiO2 nanoparticles.And this substrate presents tunable and broad localized surface plasmon resonance(LSPR),so this method may open a new way for SERS studies with other laser excitation.

  15. Novel electroless process for copper coating of flyash using titania/ultraviolet-radiation/metal catalyst-system

    International Nuclear Information System (INIS)

    A novel electroless process has been demonstrated in this investigation to coat the surface of flyash particles with a conducting metal such as copper. The conventional electroless process has been modified for this purpose by replacing the tin-palladium catalyst-system with the titania/ultraviolet-radiation/metal catalyst-system, where the metal is either copper or silver as demonstrated here. The mechanism of copper coating of flyash particles in an electroless bath, using the novel methods of surface-sensitization and surface-activation, has been systematically studied by monitoring changes in the surface-morphology, surface-chemistry, and surface-structure of flyash particles using the scanning electron microscope, energy dispersive analysis of X-rays, X-ray photoelectron spectroscope, and X-ray diffraction. It has been revealed that the novel electroless method involves coating the flyash particles with titania photocatalyst via sol-gel, which acts as a surface-sensitizer under the ultraviolet-radiation exposure for the subsequent surface-activation with the copper- or silver-clusters. The latter in turn acts as surface-catalyst for the subsequent Cu-coating in an electroless bath. The proposed mechanism of surface-sensitization and surface-activation of flyash particles using the novel catalyst-system has been compared with that using the conventional catalyst-system.

  16. Field emission properties of carbon nanotube cathodes produced using composite plating

    International Nuclear Information System (INIS)

    Field emission properties of carbon nanotube field emission cathodes (CNT-FECs) produced using composite plating are studied. The experiment uses a CNT suspension and electroless Ni plating bath to carry out composite plating. The CNTs were first purified by an acid solution, dispersed in a Ni electrobath, and finally co-deposited with Ni on glass substrates to synthesize electrically conductive films. Field emission scanning electron microscopy and Raman spectroscopy results show that the field emission characteristics and graphitic properties of CNT-FECs depend on the pH value of the electrobath. Experiments show that the optimum electrobath pH value is 5.4, achieving a field emission current density of 1.0 mA/cm2 at an applied electric field of 1.5 V/μm. The proposed CNT-FECs possess good field emission characteristics and have potential for backlight unit application in liquid crystal displays.

  17. Electroless Ni-Co-P Coating of Cenospheres Using Ag(NH3)2+ Activator

    Institute of Scientific and Technical Information of China (English)

    ZENGAi-xiang; XIONGWei-hao

    2004-01-01

    Electroless Ni-Co-P-coating of fly-ash cenosphere particles is demonstrated in the present investigation. The Electroless Ni-Co-P-coating process is modified by replacing the conventional sensitization and activation steps with only using activation step with Ag(NH3)2+ activator. The cenospheres are characterized by scanning electron microscope (SEM), energy dispersive spectroscopy (EDX), X-ray diffraction analysis (XRD) and X-ray photoelectron spectroscopy (XPS) during and after the coating process. Relatively uniform coating is obtained under the given coating conditions. The possible mechanism of electroless Ni-Co-P-coating of cenospheres utilizing Ag(NH3)2+ activator is suggested. The low density Ni-Co-P coated cenospheres may be utilized for manufacturing conducting polymers for EMI-shielding application and microwave absorbing materials.

  18. Surface modification of an epoxy resin with polyamines and polydopamine: The effect on the initial electroless copper deposition

    International Nuclear Information System (INIS)

    This paper describes the influence of polydopamine and polyamine surface modifications of an etched epoxy cresol novolak (ECN) resin on the initial electroless copper deposition. Three different strategies to introduce polyamines on a surface in aqueous environment are applied: via polyethyleneimine adsorption (PEI), via polydopamine and via polyamines grafted to polydopamine. Next, the influence of these surface modifications on the catalytic palladium activation is investigated through X-ray photoelectron spectroscopy (XPS) analysis. Finally, the initial electroless copper deposition on modified epoxy surfaces is evaluated using SEM and Energy Dispersive Spectroscopy (EDS). Grafted polyamines on polydopamine surface modifications result in a large increase of the initial deposited copper.

  19. Surface modification of an epoxy resin with polyamines and polydopamine: The effect on the initial electroless copper deposition

    Energy Technology Data Exchange (ETDEWEB)

    Schaubroeck, David, E-mail: David.Schaubroeck@elis.ugent.be [Center for Microsystems Technology (CMST), imec and Ghent University, Technologiepark 914A, B-9052 Ghent (Belgium); Mader, Lothar [Center for Microsystems Technology (CMST), imec and Ghent University, Technologiepark 914A, B-9052 Ghent (Belgium); De Geyter, Nathalie; Morent, Rino [Research Unit Plasma Technology (RUPT), Department of Applied Physics, Faculty of Engineering, Ghent University, Sint-Pietersnieuwstraat 41, B-9000 Ghent (Belgium); Dubruel, Peter [Polymer Chemistry and Biomaterials Research Group, Ghent University, Krijgslaan 281 S4 bis, B-9000 Ghent (Belgium); Vanfleteren, Jan [Center for Microsystems Technology (CMST), imec and Ghent University, Technologiepark 914A, B-9052 Ghent (Belgium)

    2014-06-01

    This paper describes the influence of polydopamine and polyamine surface modifications of an etched epoxy cresol novolak (ECN) resin on the initial electroless copper deposition. Three different strategies to introduce polyamines on a surface in aqueous environment are applied: via polyethyleneimine adsorption (PEI), via polydopamine and via polyamines grafted to polydopamine. Next, the influence of these surface modifications on the catalytic palladium activation is investigated through X-ray photoelectron spectroscopy (XPS) analysis. Finally, the initial electroless copper deposition on modified epoxy surfaces is evaluated using SEM and Energy Dispersive Spectroscopy (EDS). Grafted polyamines on polydopamine surface modifications result in a large increase of the initial deposited copper.

  20. Nanocrystallized Cu2Se grown on electroless Cu coated p-type Si using electrochemical atomic layer deposition

    Science.gov (United States)

    Zhang, Lu; He, Wenya; Chen, Xiang-yu; Du, Yi; Zhang, Xin; Shen, Yehua; Yang, Fengchun

    2015-01-01

    Cuprous selenide (Cu2Se) nanocrystalline thin films are grown onto electroless Cu coating on p-Si (100) substrates using electrochemical atomic layer deposition (EC-ALD), which includes alternate electrodeposition of Cu and Se atomic layers. The obtained films were characterized by X-ray diffraction (XRD), field emission scanning electronic microscopy (FE-SEM), FTIR, and open-circuit potential (OCP) studies. The results show the higher quality and good photoelectric properties of the Cu2Se film, suggesting that the combination of electroless coating and EC-ALD is an ideal method for deposition of compound semiconductor films on p-Si.

  1. Superhydrophobic properties of cotton fabrics functionalized with ZnO by electroless deposition

    Energy Technology Data Exchange (ETDEWEB)

    Preda, Nicoleta, E-mail: nicol@infim.ro [National Institute of Materials Physics, Magurele, Bucharest, P.O. Box MG-7, R-77125 (Romania); Enculescu, Monica; Zgura, Irina; Socol, Marcela; Matei, Elena [National Institute of Materials Physics, Magurele, Bucharest, P.O. Box MG-7, R-77125 (Romania); Vasilache, Violeta [University of Suceava, University Str. 13, 720229 Suceava (Romania); Enculescu, Ionut, E-mail: encu@infim.ro [National Institute of Materials Physics, Magurele, Bucharest, P.O. Box MG-7, R-77125 (Romania)

    2013-02-15

    Cotton fabrics were coated with arrays of ZnO hexagonal prisms using an electroless (catalytic/autocatalytic) deposition process. A typical three step method, similar to those used for electroless deposition of metals on insulating substrates, consisting of pre-activation, activation and deposition steps was employed. The low-dimensional ZnO particles were grown from an aqueous solution containing zinc nitrate as source of zinc ions and dimethylamineborane as reducing agent. The as-obtained ZnO-coated cotton fabrics were characterized from the point of view of structure by X-ray diffraction (XRD) and morphology by scanning electron microscopy (SEM). The XRD studies demonstrate that the ZnO particles have a hexagonal wurtzite crystalline structure. The SEM observations prove that the cotton fibers are homogeneously covered by hexagonal prisms which have uniform base size of approximately 500 nm and height of 1 μm. Optical spectroscopy measurements show that the functionalization with ZnO strongly decreases the transmittance in the UV–vis region of the cotton fabrics. An important characteristic is that the ZnO-functionalized cotton fabrics exhibit superhydrophobicity, with water contact angles exceeding 150°. The technique described is highly reproducible, easy scalable and cheap, allowing a wide range of applications. - Highlights: ► ZnO electroless deposition on cotton fabrics. ► Cotton fibers are homogeneously covered by ZnO hexagonal prisms. ► ZnO prisms have uniform base size of approximately 500 nm and height of 1 μm ► Coating with ZnO strongly decreases the transmittance in the UV–vis region of the fabrics. ► ZnO-coated cotton fabrics exhibit superhydrophobicity, contact angles exceeding 150°.

  2. Synthesis and tribological behaviour of electroless Ni-P-WS{sub 2} composite coatings

    Energy Technology Data Exchange (ETDEWEB)

    Sivandipoor, I., E-mail: i.sivandipoor@ma.iut.ac.ir [Department of Materials Engineering, Isfahan University of Technology, Isfahan 8415683111 (Iran, Islamic Republic of); Ashrafizadeh, F., E-mail: ashrafif@cc.iut.ac.ir [Department of Materials Engineering, Isfahan University of Technology, Isfahan 8415683111 (Iran, Islamic Republic of)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Incorporation of WS{sub 2} solid lubricant particles in Ni-P coating reduced the hardness. Black-Right-Pointing-Pointer Use of WS{sub 2} particles in the coating modified the wear behaviour of Ni-P coating. Black-Right-Pointing-Pointer WS{sub 2} particles as solid lubricant reduced the friction coefficient significantly. Black-Right-Pointing-Pointer The dominant wear mechanisms for the coatings are adhesive and abrasive. - Abstract: WS{sub 2} particles, as solid lubricant, were incorporated in electroless nickel-phosphorous to produce a new composite coating with enhanced tribological properties. Coating deposition was carried out in a laboratory electroless bath followed by heat treatment at 400 Degree-Sign C. The process included pretreatment of steel substrate by grinding and polishing to reach an appropriate roughness, surface activation by degreasing and acid cleaning and preparation of WS{sub 2} powder before addition to the electroless bath. Evaluation of friction coefficient and wear resistance was performed by a pin-on-disc tribotester at room temperature. Characterization of the surface and interface was achieved by scanning electron microscopy, microhardness measurements, X-ray diffraction and energy dispersive microanalysis to identify the chemical composition and phases in the composite coatings. Experimental results indicated that use of WS{sub 2} particles in the coating decreased the hardness and modified the wear behaviour of conventional Ni-P coating; the coefficient of friction was reduced from above 0.6 to about 0.1. The percentage of solid lubricant particles added and their distribution in the coating structure were found to be the key factors in improving the frictional behaviour of this composite coating.

  3. Effect of pickling processes on the microstructure and properties of electroless Ni–P coating on Mg–7.5Li–2Zn–1Y alloy

    Directory of Open Access Journals (Sweden)

    Chunjie Xu

    2014-12-01

    Full Text Available The electroless plating Ni–P is prepared on the surface of Mg–7.5Li–2Zn–1Y alloys with different pickling processes. The microstructure and properties of Ni–P coating are investigated. The results show that the Ni–P coatings deposited using the different pickling processes have a different high phosphorus content amorphous Ni–P solid solution structure, and the Ni–P coatings exhibit higher hardness. There is higher phosphorus content of Ni–P amorphous coating using 125 g/L CrO3 and 110 ml/L HNO3 (w=68% than using 180 g/L CrO3 and 1 g/L KF during pre-treatment, and the coating structure is more compact, and the Ni–P coatings exhibit more excellent adhesion with substrate (Fc up to 22 N. The corrosion potential of Ni–P coating is improved and exhibits good corrosion resistance. As a result, Mg-7.5Li-2Zn-1Y alloy is remarkably protected by the Ni–P coating.

  4. Preparation and Study of Electromagnetic Interference Shielding Materials Comprised of Ni-Co Coated on Web-Like Biocarbon Nanofibers via Electroless Deposition

    Directory of Open Access Journals (Sweden)

    Xiaohu Huang

    2015-01-01

    Full Text Available Electromagnetic interference (EMI shielding materials made of Ni-Co coated on web-like biocarbon nanofibers were successfully prepared by electroless plating. Biocarbon nanofibers (CF with a novel web-like structure comprised of entangled and interconnected carbon nanoribbons were obtained using bacterial cellulose pyrolyzed at 1200°C. Paraffin wax matrix composites filled with different loadings (10, 20, and 30 wt%, resp. of CF and Ni-Co coated CF (NCCF were prepared. The electrical conductivities and electromagnetic parameters of the composites were investigated by the four-probe method and vector network analysis. From these results, the EMI shielding efficiencies (SE of NCCF composites were shown to be significantly higher than that of CF at the same mass fraction. The paraffin wax composites containing 30 wt% NCCF showed the highest EMI SE of 41.2 dB (99.99% attenuation, which are attributed to the higher electrical conductivity and permittivity of the NCCF composites than the CF composites. Additionally, EMI SE increased with an increase in CF and NCCF loading and the absorption was determined to be the primary factor governing EMI shielding. This study conclusively reveals that NCCF composites have potential applications as EMI shielding materials.

  5. Corrosion Resistance Enhancement of AZ91D Magnesium Alloy by Electroless Ni-Co-P Coating and Ni-Co-P-SiO2 Nanocomposite

    Science.gov (United States)

    Seifzadeh, Davod; Rahimzadeh Hollagh, Amin

    2014-08-01

    Electroless Ni-Co-P coating and Ni-Co-P-SiO2 nanocomposites were successfully applied on AZ91D magnesium alloy via environmentally friendly cerium-lanthanum-permanganate treatment and their properties were compared with traditionally binary Ni-P coating. The prepared coatings were analyzed using scanning electron microscopy, x-ray diffraction, and energy dispersive x-ray spectroscopy. Moreover, the corrosion behavior of the coatings in 3.5 wt.% NaCl was evaluated by two electrochemical methods. It is found that the Ni-Co-P coating possesses more uniform and compact structure and better corrosion protection characteristics in comparison with the Ni-P coating. The plating rate of Ni-Co-P bath is relatively lower than the Ni-P bath, but it significantly increases after addition of SiO2 nanoparticles more probably due to adsorption of silica nanoparticles on alloy surface. The corrosion resistance of Ni-Co-P-SiO2 composite coatings was superior with respect to Ni-P and Ni-Co-P coatings due to formation of thick and compact coating with tortuous grain boundaries.

  6. Effect of pickling processes on the microstructure and properties of electroless Ni-P coating on Mg-7.5Li-2Zn-1Y alloy

    Institute of Scientific and Technical Information of China (English)

    Chunjie Xu; Liping Chen; Ling Yu; Jinxiao Zhang; Zhongming Zhang; Jincheng Wang

    2014-01-01

    The electroless plating Ni–P is prepared on the surface of Mg–7.5Li–2Zn–1Y alloys with different pickling processes. The microstructure and properties of Ni–P coating are investigated. The results show that the Ni–P coatings deposited using the different pickling processes have a different high phosphorus content amorphous Ni–P solid solution structure, and the Ni–P coatings exhibit higher hardness. There is higher phosphorus content of Ni–P amorphous coating using 125 g/L CrO3 and 110 ml/L HNO3 (w=68%) than using 180 g/L CrO3 and 1 g/L KF during pre-treatment, and the coating structure is more compact, and the Ni–P coatings exhibit more excellent adhesion with substrate (Fc up to 22 N). The corrosion potential of Ni–P coating is improved and exhibits good corrosion resistance. As a result, Mg-7.5Li-2Zn-1Y alloy is remarkably protected by the Ni–P coating.

  7. Research Progress in Solderable Black Pad of Electroless Nickel/Immersion Gold

    Institute of Scientific and Technical Information of China (English)

    Liu Haiping; Li Ning; Bi Sifu; Li Deyu

    2007-01-01

    Electroless nickel/immersion gold (ENIG) technology is widely used as one of the surface final finish for electronics packaging substrate and printed circuit board (PCB), providing a protective, conductive and solderable surface. However, there is a solder joint interfacial brittle fracture (or solderability failure) of using the ENIG coating. The characteristics and the application of ENIG technology were narrated in this paper. The research progress on the solderability failure of ENIG was introduced. The mechanism of "black pad" and the possible measure of eliminating or alleviating the "black pad" were also introduced. The development direction and market prospects of ENIG were prospected.

  8. Self-organized synthesis of silver dendritic nanostructures via an electroless metal deposition method

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, T. [Nanjing University, Department of Physics, Nanjing (China); City University of Hong Kong, Department of Physics and Materials Science, Kowloon, Hong Kong (China); Wu, X.L. [Nanjing University, Department of Physics, Nanjing (China); Mei, Y.F.; Chu, P.K.; Siu, G.G. [City University of Hong Kong, Department of Physics and Materials Science, Kowloon, Hong Kong (China)

    2005-09-01

    Unique silver dendritic nanostructures, with stems, branches, and leaves, were synthesized with self-organization via a simple electroless metal deposition method in a conventional autoclave containing aqueous HF and AgNO{sub 3} solution. Their growth mechanisms are discussed in detail on the basis of a self-assembled localized microscopic electrochemical cell model. A process of diffusion-limited aggregation is suggested for the formation of the silver dendritic nanostructures. This nanostructured material is of great potential to be building blocks for assembling mini-functional devices of the next generation. (orig.)

  9. Wear Performance Optimization of Electroless Ni-B Coating Using Taguchi Design of Experiments

    OpenAIRE

    Das, S. K.; Sahoo, P.

    2010-01-01

    The present study outlines the use of Taguchi parameter design to minimize the wear performance of electroless Ni-B coating by optimizing the tribological testing parameters. The tests are carried out in a multi- tribotester and the three parameters viz. load (L), speed (S) and time (T) are considered with three levels each. An L27 array is used to accommodate the three factors as well as their interaction effects. The Taguchi experiments gave the optimal combination of parameters L1S2T1 (50 ...

  10. Tribological Behavior of Electroless Ni-P Coating in Brine Environment

    Science.gov (United States)

    Panja, B.; Das, S. K.; Sahoo, P.

    2014-10-01

    The present paper reports an experimental study of tribological behaviour of electroless Ni-P coating in brine environment sliding against alumina. The study of wear and friction behaviour is carried out using different load and sliding velocity with the help of a pin-on-disk wear and friction monitor. The friction coefficient decreases with increase in applied load and sliding velocity. The wear rate increases with increase in sliding velocity and also gradually increases with the increase in applied load. The surface morphology, composition of coatings and crystalline structure are studied with the help of scanning electron microscopy, energy dispersed X-ray analysis and X-ray diffraction analysis respectively.

  11. Electroless Deposition of W-doped Ag Dendrites from HF Solution

    Institute of Scientific and Technical Information of China (English)

    YE Wei-Chun; MA Chuan-Li; CHANG Yan-Long; WANG Chun-Ming

    2008-01-01

    A simple method was developed for the preparation of W-doped Ag dendrites by using electroless deposition from hydrofluoride solution. The samples characterized by XPS, XRD, SEM and TEM techniques, show that the growth of silver is leading and can not be changed essentially by tungstate ions in the Ag-W binary system. A doping mode of W element was proposed, i.e., the doping of W may occur during silver deposition through chemi-sorption-chemical bonding of oxygen atoms of tungstate dimer with silver. Cyclic voltammetry was employed to determine the chemical bonding energy between silver and oxygen.

  12. Electrochemical Tailoring of Fibrous Polyaniline and Electroless Decoration with Gold and Platinum Nanoparticles.

    Science.gov (United States)

    Abdelhamid, Muhammad E; Snook, Graeme A; O'Mullane, Anthony P

    2016-09-01

    Presented in this work is a facile and quick electrochemical method for controlling the morphology of thick polyaniline (PANi) films, without the use of templates. By stepping the polymerization potential from high voltages to a lower (or series of lower) voltage(s), we successfully controlled the morphology of the polymer, and fibrous structures, unique to each potential step, were achieved. In addition, the resultant film was tested electrochemically for its viability as an electrode material for flexible batteries and supercapacitors. Furthermore, the PANi film was decorated with gold and platinum nanoparticles via an electroless deposition process for possible electrocatalytic applications, whereby the oxidation of hydrazine at the composite was investigated. PMID:27531044

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  15. Electroless Ni- P- Cf Complex Plating%化学复合镀Ni-P-Cf工艺的研究

    Institute of Scientific and Technical Information of China (English)

    刘秉余; 穆柏椿; 由向群

    2001-01-01

    研究了化学复合镀Ni-P-Cf工艺及碳纤维对镀速、镀层硬度和耐磨性的影响,探讨了碳纤维提高镀速、镀层硬度、耐磨性的机理。结果表明:加入碳纤维,使Ni-P合金镀速和镀层硬度显著提高;经500 ℃时效处理后,耐磨性比普通Ni-P镀层提高5倍多。本工艺为:20 g/L硫酸镍,25 g/L次亚磷酸钠,30 g/L络合剂,1 g/L加速剂,1 mg/L稳定剂,微量表面活性剂,pH=4.7,温度为85±1 ℃。%The effects of technological parameters and carbon fibre on the hardness and wear resistance of the deposit were investigated and discussed.The experimental results showed that the addition of carbon fibre could obviously increase the hardness.After ageing at 500 ℃ the wear resistance of the Ni- P- Cf coating could be 6 times as high as that of Ni- P coating.

  16. Chip integration using inkjet-printed silver conductive tracks reinforced by electroless plating for flexible board packages

    OpenAIRE

    Cauchois, Romain; Saadaoui, Mohamed; Legeleux, Jacques; Malia, Thierry; Dubois-Bonvalot, Béatrice; Inal, Karim; Fidalgo, Jean-Christophe

    2012-01-01

    International audience Inkjet-printing of interconnects is a maskless technology that has attracted great interest for printed electronics and packaging applications. Gemalto is expecting by motivated and developing skills and knowledge in this area to be at the forefront of European Security innovation and to answer to a continuous market pressure for higher security, lower cost and more secure complex systems. With an increasing need for flexible and mass deliveries of advanced secure pe...

  17. 电磁场在化学镀中的影响%Effects of Electromagnetic Field in Electroless Plating

    Institute of Scientific and Technical Information of China (English)

    陈红辉; 陈通杰

    2004-01-01

    通过对溶液中离子磁化现象的研究,在电磁场作用下,化学镀沉积速率加快,所得镀层结构致密,镀层中磷含量比常规化学镀镍液的降低,镀层的物理性能也得到了较大的改善.

  18. Application of Electroless Plating in Electromagnetic Shielding%化学镀在电磁屏蔽中的应用

    Institute of Scientific and Technical Information of China (English)

    吴春; 刘祥萱; 黄洁

    2010-01-01

    化学镀技术作为一种材料表面金属化的手段,已经广泛应用于制备各种电磁屏蔽材料.简要分析了化学镀层电磁屏蔽的基本原理,并重点讨论了多种非金属基材化学镀层用于电磁屏蔽材料方面的研究现状及应用前景.

  19. Effect of Addition of Polytetrafluoroethylene (PTFE) and Silicon Carbide (SIC) on Properties of Electroless Nickel AHoy Coatings

    Institute of Scientific and Technical Information of China (English)

    WUYu-cheng; HUXiao-ye; WANGWen.fang; HUANGXin-min

    2004-01-01

    Electroless nickel (copper)-phosphorus-silicon carbide (SiC)-polytetrafluorocthylene(PTFE) composite coatigs were prepared by adding SiC and PTFE into electroless nickel(copper)-phosphorus alloy baths.The effects of addition of SiC and PTFE on depositing rate.microhardness.wear resistance and anti-fiction of the resulted composite coatings were studied.The results indicated that electroless nickel(copper).phosphorus alloy coatings were grealty improved in depositing rate,microhardness,wear resistance and antifriction by co-deposited proper amount of SiC and PTFE.

  20. Surface modification of battery electrodes via electroless deposition with improved performance for Na-ion batteries.

    Science.gov (United States)

    Lahiri, Abhishek; Olschewski, Mark; Gustus, René; Borisenko, Natalia; Endres, Frank

    2016-06-01

    Sodium-ion batteries (SIBs) are emerging as potential stationary energy storage devices due to the abundance and low cost of sodium. A simple and energy efficient strategy to develop electrodes for SIBs with a high charge/discharge rate is highly desirable. Here we demonstrate that by surface modification of Ge, using electroless deposition in SbCl3/ionic liquids, the stability and performance of the anode can be improved. This is due to the formation of GexSb1-x at the surface leading to better diffusion of Na, and the formation of a stable twin organic and inorganic SEI which protects the electrode. By judicious control of the surface modification, an improvement in the capacity to between 50% and 300% has been achieved at high current densities (0.83-8.4 A g(-1)) in an ionic liquid electrolyte NaFSI-[Py1,4]FSI. The results clearly demonstrate that an electroless deposition based surface modification strategy in ionic liquids offers exciting opportunities in developing superior energy storage devices. PMID:27189079

  1. Hall Measurements on Carbon Nanotube Paper Modified With Electroless Deposited Platinum

    Directory of Open Access Journals (Sweden)

    Iwuoha Emmanuel

    2009-01-01

    Full Text Available Abstract Carbon nanotube paper, sometimes referred to as bucky paper, is a random arrangement of carbon nanotubes meshed into a single robust structure, which can be manipulated with relative ease. Multi-walled carbon nanotubes were used to make the nanotube paper, and were subsequently modified with platinum using an electroless deposition method based on substrate enhanced electroless deposition. This involves the use of a sacrificial metal substrate that undergoes electro-dissolution while the platinum metal deposits out of solution onto the nanotube paper via a galvanic displacement reaction. The samples were characterized using SEM/EDS, and Hall-effect measurements. The SEM/EDS analysis clearly revealed deposits of platinum (Pt distributed over the nanotube paper surface, and the qualitative elemental analysis revealed co-deposition of other elements from the metal substrates used. When stainless steel was used as sacrificial metal a large degree of Pt contamination with various other metals was observed. Whereas when pure sacrificial metals were used bimetallic Pt clusters resulted. The co-deposition of a bimetallic system upon carbon nanotubes was a function of the metal type and the time of exposure. Hall-effect measurements revealed some interesting fluctuations in sheet carrier density and the dominant carrier switched from N- to P-type when Pt was deposited onto the nanotube paper. Perspectives on the use of the nanotube paper as a replacement to traditional carbon cloth in water electrolysis systems are also discussed.

  2. Wear Performance Optimization of Electroless Ni-B Coating Using Taguchi Design of Experiments

    Directory of Open Access Journals (Sweden)

    S. K. DAS

    2010-12-01

    Full Text Available The present study outlines the use of Taguchi parameter design to minimize the wear performance of electroless Ni-B coating by optimizing the tribological testing parameters. The tests are carried out in a multi- tribotester and the three parameters viz. load (L, speed (S and time (T are considered with three levels each. An L27 array is used to accommodate the three factors as well as their interaction effects. The Taguchi experiments gave the optimal combination of parameters L1S2T1 (50 N for load, 60 rpm for speed and 5 minute for time. Furthermore, a statistical analysis of variance reveals that both load and time have significant influence over the wear behavior of electroless coating. Also the interaction between load and speed and that between load and time influence wear quite significantly. The coating is characterized using scanning electron microscopy, energy dispersive X-ray analysis and X-ray diffraction analysis. The wear mechanism is also studied and found to be abrasive in nature.

  3. Fabrication of micro-Ni arrays by electroless and electrochemical depositions with etched porous aluminum template

    Indian Academy of Sciences (India)

    Houfang Lu; Kangping Yan; Jixin Yan; Jianzhong Wang

    2010-10-01

    Nickel micro-arrays were fabricated by electroless and electrochemical deposition in an etched porous aluminum membrane. The aluminum membrane with metal characteristic could be fabricated from high-purity aluminium by electrochemical method. The aluminum reduced Ni2+ into Ni and the formed Ni nuclei served as the catalyst for further reduction of Ni2+ in electroless solution. With the help of the membrane, nickel micro-columns of about 1–2 m diameter were obtained. The surface-deposited nickel layer served as a substrate for the nickel micro-columns, and the resulting material possessed strong mechanical strength. Electrochemical deposition was operated without preparing a conductive layer on the template due to the conductivity of the aluminum membrane. Nickel micro-tubes with an outer diameter of about 1–2 m and a wall thickness in the order of tens of nm were obtained. The nickel micro-arrays were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS).

  4. Effect of strontium tantalate surface texture on nickel nanoparticle dispersion by electroless deposition

    Energy Technology Data Exchange (ETDEWEB)

    Compean-González, C.L. [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Civil, Departamento de Ecomateriales y Energía, Av. Universidad s/n, Ciudad Universitaria, San Nicolás de los Garza, Nuevo León C.P. 66451 (Mexico); Arredondo-Torres, V.M. [Facultad de Químico Farmacobiología, Universidad Michoacana de San Nicolás de Hidalgo, Tzintzuntzan #173, Col. Matamoros, Morelia, Michoacán C.P. 58240 (Mexico); Zarazúa-Morin, M.E. [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Civil, Departamento de Ecomateriales y Energía, Av. Universidad s/n, Ciudad Universitaria, San Nicolás de los Garza, Nuevo León C.P. 66451 (Mexico); Figueroa-Torres, M.Z., E-mail: m.zyzlila@gmail.com [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Civil, Departamento de Ecomateriales y Energía, Av. Universidad s/n, Ciudad Universitaria, San Nicolás de los Garza, Nuevo León C.P. 66451 (Mexico)

    2015-09-15

    Highlights: • Efficient short-time procedure for nickel nanoparticles dispersion by electroless. • Nanoparticles are spherical in shape with an average size of 15 nm. • Influence of surface texture on deposition temperature and time was observed. • Nickel deposition can be done below 50 °C. - Abstract: The present work studies the effect of smooth and porous texture of Sr{sub 2}Ta{sub 2}O{sub 7} on its surface modification with nickel nanoparticles through electroless deposition technique. The influence of temperature to control Ni nanoparticles loading amount and dispersion were analyzed. Nitrogen adsorption isotherms were used to examine surface texture characteristics. The morphology was observed by scanning electron microscopy (MEB) equipped with an energy dispersive spectrometry system (EDS), which was used to determine the amount of deposited Ni. The material with smooth texture (SMT) consists of big agglomerates of semispherical shape particles of 400 nm. Whilst the porous texture (PRT) exhibit a pore-wall formed of needles shape particles of around 200 nm in size. Results indicated that texture characteristics strongly influence the deposition reaction rate; for PRT oxide, Ni deposition can be done from 20 °C while for SMT oxide deposition begins at 40 °C. Analysis of Sr{sub 2}Ta{sub 2}O{sub 7} surface indicated that in both textures, Ni nanoparticles with spherical shape in the range of 10–20 nm were obtained.

  5. Electroless metal deposition used as underbump metallization (UBM) for high temperature application - a comparison to other bumping techniques

    Energy Technology Data Exchange (ETDEWEB)

    Anhoeck, S.; Ostmann, A.; Oppermann, H. [Technische Univ. Berlin (Germany). Forschungsschwerpunkt Technologien der Mikroperipherik; Aschenbrenner, R.; Reichl, H.

    2000-07-01

    Electronic components are more and more applied at higher operation temperatures. One reason is increasing density of electronic power. Another reason is the application of electronic components directly at high temperature modules especially for automotive application. For the reliability of such high-temperature assemblies the choice of metallurgical system is very important. Critical issues for the high-temperature reliability are the phase formation and phase growth of intermetallics between the solder and the end-metallization. The electroless Ni seems to be a suitable metallization for high temperature solders. Due to the nature of the electroless deposition process the deposits consist of Ni and P and shows an amorphous structure. Compared to other materials such as Cu, Cr, Pt, Pd the phase growth of the intermetallics at the interface between solder and Ni is slow. The phosphorous seems to inhibit the Ni diffusion into the solder by formation of a phosphor-rich layer close to the interface of solder and final metallization. The focus of the paper is to summarize the results from aging of AuSn20 solder preforms on different metallizations such as Cu, Cr, Ni, Pd and Pt to find a suitable metallization for high temperature application. Furthermore the reaction of PbSn63 solder preforms on different Ni metallizations such as electroless deposited Ni, electroplated Ni and pure Ni bulk metallization will be discussed. Differences in the phases growth due to the electroless deposition will be described. (orig.)

  6. Processless offset printing plates

    Directory of Open Access Journals (Sweden)

    Sanja Mahović Poljaček

    2015-06-01

    Full Text Available With the implementation of platesetters in the offset printing plate making process, imaging of the printing plate became more stable and ensured increase of the printing plate quality. But as the chemical processing of the printing plates still highly influences the plate making process and the graphic reproduction workflow, development of printing plates that do not require chemical processing for offset printing technique has been one of the top interests in graphic technology in the last few years. The main reason for that came from the user experience, where majority of the problems with plate making process could be connected with the chemical processing of the printing plate. Furthermore, increased environmental standards lead to reducing of the chemicals used in the industrial processes. Considering these facts, different types of offset printing plates have been introduced to the market today. This paper presents some of the processless printing plates.

  7. Electroless copper on refractory and noble metal substrates with an ultra-thin plasma-assisted atomic layer deposited palladium layer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young-Soon [Thin Film Technology Lab, School of Chemical Engineering, Chonbuk National University, Jeonju 561756 (Korea, Republic of); Kim, Hyung-Il [Thin Film Technology Lab, School of Chemical Engineering, Chonbuk National University, Jeonju 561756 (Korea, Republic of); Cho, Joong-Hee [Thin Film Technology Lab, School of Chemical Engineering, Chonbuk National University, Jeonju 561756 (Korea, Republic of); Seo, Hyung-Kee [Thin Film Technology Lab, School of Chemical Engineering, Chonbuk National University, Jeonju 561756 (Korea, Republic of); Dar, M.A. [Thin Film Technology Lab, School of Chemical Engineering, Chonbuk National University, Jeonju 561756 (Korea, Republic of); Shin, Hyung-Shik [Thin Film Technology Lab, School of Chemical Engineering, Chonbuk National University, Jeonju 561756 (Korea, Republic of); Ten Eyck, Gregory A. [Department of Physics, Rensselaer Polytechnic Institute, Troy, NY 12180 (United States); Lu, Toh-Ming [Department of Physics, Rensselaer Polytechnic Institute, Troy, NY 12180 (United States); Senkevich, Jay J. [Brewer Science Inc., Rolla, MO 65401 (United States)]. E-mail: jsenkevich@brewerscience.com

    2006-02-25

    Electroless Cu was investigated on refractory metal, W and TaN {sub X}, and Ir noble metal substrates with a plasma-assisted atomic layer deposited palladium layer for the potential back-end-of-the-line (BEOL) metallization of advanced integrated devices. The sodium and potassium-free Cu electroless bath consisted of: ethylenediamine tetraacetic acid (EDTA) as a chelating agent, glyoxylic acid as a reducing agent, and additional chemicals such as polyethylene glycol, 2,2'-dipyridine and RE-610 as surfactant, stabilizer and wetting agent respectively. The growth and chemical characterization of the Cu films was carried out with a field emission scanning electron microscope (FE-SEM), X-ray photoelectron spectroscopy (XPS), and Rutherford backscattering spectrometry (RBS). Group VIII metals such as Pt, Pd, etc., are stable in the electroless bath and catalytic towards the oxidation of glyoxylic acid and therefore work well for the electroless deposition of Cu. From RBS analysis, the amount of carbon and oxygen in Cu films were less than 1-3%. The Cu films were electroless deposited at 45-50 deg. C on patterned tantalum nitride with plasma-assisted atomic layer deposited (PA-ALD) Pd as a catalytic layer. Electroless Cu trench fill was successful with ultrasonic vibration, RE-610, and lowering the temperature to 45-50 deg. C on TaN {sub X} with the PA-ALD Pd catalytic layer.

  8. A study of corrosion performance of electroless Ni-P and Ni-W-P coatings on AZ91D magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Liao, Y.; Dryfe, R. [School of Chemistry, University of Manchester, Manchester (United Kingdom); Zhang, S.T. [College of Chemistry and Chemical Engineering, University of Chongqing, Chongqing (China)

    2011-09-15

    The autocatalytic nature of the electroless nickel-based alloy coating process will inevitably produce H{sub 2} bubbles which may be left in electroless nickel-based alloy coating. If the H{sub 2} cannot be removed and left in the coating, it can lead to its poor corrosion resistance due to hydrogen cracks. So, the post treatment is an essential step for electroless deposition process. In this paper, electroless Ni-P and Ni-W-P coatings with chromium-free pretreatment and dehydrogenation post treatment have been successfully prepared on AZ91D magnesium alloy, and the corrosion behaviors of the two kind coating samples in NaCl solution, HCl solution, and H{sub 2}SO{sub 4} solution have been investigated. Both the polarization test and immersion tests show that the electroless Ni-W-P coating has better corrosion resistance than that of electroless Ni-P coating. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  9. NiCo-lead zirconium titanate-NiCo trilayered magnetoelectric composites prepared by electroless deposition

    Directory of Open Access Journals (Sweden)

    M. H. Zhou

    2015-04-01

    Full Text Available The NiCo layers with various Ni/Co atomic ratio have been successfully electroless deposited on PZT layers by varying the bath composition. As the cobalt atomic ratio in the deposited layer increases from 17.2 to 54.8 wt%, the magnetostrictive coefficient decreases. The magnetoelectric effect depends strongly on the magnetostrictive properties of magnetostrictive phase. The magnetoelectric coefficient of NiCo/PZT/NiCo trilayers increases with Ni/Co atomic ratio of the deposited NiCo layers increasing from 45:55 to 83:17. A maximum ME voltage coefficient of αE,31 = 2.8 V ⋅ cm−1 ⋅ Oe−1 is obtained at a frequency of about 88 kHz, which makes these trilayers suitable for applications in actuators, transducers and sensors.

  10. Effect of Pd precursor status on sonochemical surface activation in Cu electroless deposition

    Science.gov (United States)

    Kim, Kanghoon; Jin, Seonok; Kwon, Oh Joong

    2016-02-01

    Pd surface activation via a sonochemical approach was studied by varying Pd precursor status in the aqueous solution. By aging a K2PdCl6 activation solution overnight with added NH4OH, the chlorinated Pd complex was changed to an ammonia-based Pd complex. The Pd surface activation carried out with the NH4OH complexing agent resulted in improved surface condition following Cu electroless deposition. The Cu thin film deposited on a substrate sonochemically activated with the aged, ammonia-based Pd complex showed improved surface roughness and resistivity compared to that for Cu films deposited via two other precursors (chlorinated Pd complex and ammonia-based complex) without aging. In addition, nitrogen purging during sonochemical activation improved Cu film quality.

  11. Electroless porous silicon formation applied to fabrication of boron-silica-glass cantilevers

    DEFF Research Database (Denmark)

    Teva, Jordi; Davis, Zachary James; Hansen, Ole

    2010-01-01

    This work describes the characterization and optimization of anisotropic formation of porous silicon in large volumes (0.5-1 mm3) of silicon by an electroless wet etching technique. The main goal is to use porous silicon as a sacrificial volume for bulk micromachining processes, especially in cases...... where etching of the full wafer thickness is needed. The porous silicon volume is formed by a metal-assisted etching in a wet chemical solution composed of hydrogen peroxide (30%), hydrofluoric acid (40%) and ethanol. This paper focuses on optimizing the etching conditions in terms of maximizing...... for bio-chemical sensors. The porous silicon volume is formed in an early step of the fabrication process, allowing easy handling of the wafer during all of the micromachining processes in the process flow. In the final process step, the porous silicon is quickly etched by immersing the wafer in a KOH...

  12. Electroless deposition of Cu dendrites decorated with ZnO rods

    Energy Technology Data Exchange (ETDEWEB)

    Wang, L.; Liu, G.; Xue, D. [Department of Materials Science and Chemical Engineering, School of Chemical Engineering, Dalian University of Technology, 158 Zhongshan Road, Dalian 116012 (China)

    2011-07-15

    In this paper, copper dendrites decorated with ZnO rods have been electrolessly deposited on brass substrate by a simple galvanic replacement method. SEM images show that these copper dendrites possess a pronounced trunk and highly ordered branches distributed on both sides of the trunk. Meanwhile, both the trunk and branches are decorated with ZnO rods. The diffusion-limited aggregation (DLA) model has been used to explain the fractal growth of Cu dendritic structures. This method provides a facile route to the synthesis of copper dendrites with ZnO, which can be extended to the preparation of other forms three-dimensional (3-D) metal structures or metal/ZnO composites by modifying electrolyte parameters such as composition, concentration, pH and temperature. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  13. Effects of zincate treatment on adhesion of electroless Ni-P coating onto various aluminum alloys

    Institute of Scientific and Technical Information of China (English)

    Makoto HINO; Koji MURAKAMI; Yutaka MITOOKA; Ken MURAOKA; Teruto KANADANI

    2009-01-01

    The effects of alloying elements on zincate treatment and adhesion of electroless Ni-P coating onto various aluminum alloy substrates were examined. Surface morphology of zinc deposits in the 1st zincate treatment and its adhesion were changed depending on the alloying element. The zinc deposits in the 2nd zincate treatment became thinly uniform, and the adhesion between aluminum alloy substrate and Ni-P coating was improved irrespective of the alloying element. XPS analysis revealed the existence of zinc on the surface of each aluminum alloy substrate after the pickling in 5% nitric acid. This zinc on the surface should be an important factor influencing the morphology of zinc deposit at the 2nd zincate treatment and its adhesion.

  14. Preparation of superhydrophobic silver nano coatings with feather-like structures by electroless galvanic deposition

    Institute of Scientific and Technical Information of China (English)

    FENG XiaoJuan; SHI YanLong; WANG YongSheng; YUE GuoRen; YANG Wu

    2013-01-01

    Superhydrophobic silver nanocoatings with feather-like morphology are fabricated on copper substrates by electroless galvanic deposition.The coating exhibit superhydrophobicity with a contact angle of 156.4° and glide angle of 4° without any further surface modification.Scanning electron microscope (SEM),X-ray diffraction (XRD) and contact angle measurements are used to investigate the morphology,crystal structure and superhydrophobicity,respectively,of the coatings.The coatings exhibit high thermal stability; their water contact angle did not change when the coatings were heated to 200℃ for 2 h.The mechanism of superhydrophobicity of the silver coating is discussed based on the work of Amirfazli,Wenzel and Cassie.

  15. Electroless Silver Coating on Copper Microcones for Low-Temperature Solid-State Bonding

    Science.gov (United States)

    Hu, Fengtian; Yang, Shan; Wang, Haozhe; Hu, Anmin; Li, Ming

    2015-11-01

    A low-temperature solid-state bonding technology using silver-coated Cu microcones and Sn-3.0Ag-0.5Cu (wt.%) solder for three-dimensional (3D) packaging is presented. Electroless silver coating on the surfaces of copper microcones effectively reduces oxide layer growth and significantly enhances the solder joint shear strength from an average of 33.5 MPa to 43.4 MPa. Low-temperature thermocompression bonding at 463 K in ambient air was achieved using silver-coated Cu microcones, with no voids found along the bonded interface. Microscopic observation revealed that the microcones were completely inserted into the soft solder. Probable mechanisms for this bonding process are proposed and discussed.

  16. Preparation of Core-shell Cu-Ag Bimetallic Powder via Electroless Coating

    Institute of Scientific and Technical Information of China (English)

    XU Rui; ZHOU Kanggen; HU Minyi

    2009-01-01

    A novel method of electroless silver coating on copper powders was reported,in which hydrazine was used as the reducing agent,and had some advantages such was used as inhib-iting the substitution reaction and reducing consumption of copper powders.In the processes of sen-sitization and activation,AgNO_3 replaces the conventional PdCl_2,which solves the impurity of bath.Oxide film on the surface of copper powders was tested by chemical analysis.Ag element tested by XRD and XRF is in the form of Ag~0 and exists on the surface of copper powders,which acts as catalyzer in reduction reaction.Morphology and composition of the coating were characterized by SEM and XRD respectively.

  17. Silicon nanowire arrays coated with electroless Ag for increased surface-enhanced Raman scattering

    Science.gov (United States)

    Bai, Fan; Li, Meicheng; Fu, Pengfei; Li, Ruike; Gu, Tiansheng; Huang, Rui; Chen, Zhao; Jiang, Bing; Li, Yingfeng

    2015-05-01

    The ordered Ag nanorod (AgNR) arrays are fabricated through a simple electroless deposition technique using the isolated Si nanowire (SiNW) arrays as the Ag-grown scaffold. The AgNR arrays have the single-crystallized structure and the plasmonic crystal feature. It is found that the formation of the AgNR arrays is strongly dependent on the filling ratio of SiNWs. A mechanism is proposed based on the selective nucleation and the synergistic growth of Ag nanoparticles on the top of the SiNWs. Moreover, the special AgNR arrays grown on the substrate of SiNWs exhibit a detection sensitivity of 10-15M for rhodamine 6G molecules, which have the potential application to the highly sensitive surface-enhanced Raman scattering sensors.

  18. NiCo-lead zirconium titanate-NiCo trilayered magnetoelectric composites prepared by electroless deposition

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, M. H.; Wang, Y. G.; Bi, K., E-mail: bike@bupt.edu.cn [State Key Laboratory of Information Photonics and Optical Communications and School of Science, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Fan, H. P. [School of Mechanical and Electrical Engineering, Qingdao Technological University Qindao College, Qingdao 266106 (China); Zhao, Z. S. [Shandong Engineering Consulting Institute, Jinan 250013 (China)

    2015-04-15

    The NiCo layers with various Ni/Co atomic ratio have been successfully electroless deposited on PZT layers by varying the bath composition. As the cobalt atomic ratio in the deposited layer increases from 17.2 to 54.8 wt%, the magnetostrictive coefficient decreases. The magnetoelectric effect depends strongly on the magnetostrictive properties of magnetostrictive phase. The magnetoelectric coefficient of NiCo/PZT/NiCo trilayers increases with Ni/Co atomic ratio of the deposited NiCo layers increasing from 45:55 to 83:17. A maximum ME voltage coefficient of α{sub E,31} = 2.8 V ⋅ cm{sup −1} ⋅ Oe{sup −1} is obtained at a frequency of about 88 kHz, which makes these trilayers suitable for applications in actuators, transducers and sensors.

  19. Tribological Performance Optimization of Electroless Ni-P-W Coating Using Weighted Principal Component Analysis

    Directory of Open Access Journals (Sweden)

    S. Roy

    2013-12-01

    Full Text Available The present investigation is an experimental approach to deposit electroless Ni-P-W coating on mild steel substrate and find out the optimum combination of various tribological performances on the basis of minimum friction and wear, using weighted principal component analysis (WPCA. In this study three main tribological parameters are chosen viz. load (A, speed (B and time(C. The responses are coefficient of friction and wear depth. Here Weighted Principal Component Analysis (WPCA method is adopted to convert the multi-responses into single performance index called multiple performance index (MPI and Taguchi L27 orthogonal array is used to design the experiment and to find the optimum combination of tribological parameters for minimum coefficient of friction and wear depth. ANOVA is performed to find the significance of the each tribological process parameters and their interactions. The EDX analysis, SEM and XRD are performed to study the composition and structural aspects.

  20. Study on the laser treatment of electroless Ni-P-SiC composite coatings

    Institute of Scientific and Technical Information of China (English)

    Honghong Shao; Xiaoyan Jiang; Lan Wang; Yinqun Hua

    2006-01-01

    Effect of the laser treatment on electroless Ni-P-SiC composite coatings was investigated. The microscopic structure, surface morphology, ingredient, and performance of the Ni-P-SiC composite coatings were synthetically analyzed by the use of X-ray diffraction apparatus, scanning electron microscope, energy distribution spectrometer, micro-hardness tester, wear tester and so on. It was found that the composite coatings did make crystalloblastic transformation after laser heating. Structural analysis confirmed that some new types of phase Ni2Si or Ni3Si compound would emerge in the Ni-P-SiC coatings after laser treatment. The micro-hardness measurement results showed that when the laser power was 450 W with scanning speed of 0.5 m/min, the hardness of the coating was superior to the coating obtained by the conventional furnace heating, and wear resistance of the composite coating after laser treating could also improve.

  1. Electroless synthesis of lepidocrocite ({gamma}-FeOOH) nanotubes in ion track etched polycarbonate templates

    Energy Technology Data Exchange (ETDEWEB)

    Neetzel, C., E-mail: Neetzel@ca.tu-darmstadt.de [Darmstadt University of Technology, Department of Materials Science, Materials Analysis Group, D-64287 Darmstadt (Germany); Gasi, T.; Ksenofontov, V.; Felser, C. [Johannes Gutenberg University of Mainz, Institute of Inorganic and Analytical Chemistry, D-55128 Mainz (Germany); Ionescu, E. [Darmstadt University of Technology, Department of Materials Science, Dispersive Solids, D-64287 Darmstadt (Germany); Ensinger, W. [Darmstadt University of Technology, Department of Materials Science, Materials Analysis Group, D-64287 Darmstadt (Germany)

    2012-07-01

    In this study, we describe the electroless synthesis of lepidocrocite ({gamma}-FeOOH) nanotubes produced in ion track etched polycarbonate foils. The foils act as templates after they had been irradiated with heavy ions to produce latent tracks that were etched with a desired diameter. Templates are used to fabricate shape formed 1D nanostructures in general. The synthesis of lepidocrocite nanotubes was carried out in a simple two-step method: firstly, particles were formed by precipitation in aqueous solution; secondly, nanotubes were produced by the deposition of the particles inside the nanochannels of the polycarbonate template. Solvent effects were considered to achieve homogeneous growth resulting in well-defined nanotubes of constant wall thickness along the tube axis. Lepidocrocite nanotubes were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), Raman, and Moessbauer spectroscopy.

  2. 代银镀层技术研究进展%Advances in Research on Plating Technology of Substitute for Silver Coating

    Institute of Scientific and Technical Information of China (English)

    王崇蕊; 郝建军; 董春艳; 刘新院

    2011-01-01

    Several plating methods of substitute for Silver coating such as tin electroplating with sulfate electrolyte, Sn-Ce and acid bright Sn-Ce-Bi alloy electroplating were described. Ni-P/Ni-B double-layer electroless plating, and tin electroless plating followed by Sn-Ce-Sb electroplating method were also introduced. The characteristics of these plating methods were briefly summarized, and the developing trends of these methods were put forward.%介绍了几种替代银镀层的镀覆方法,其中有硫酸盐电解液镀锡、电镀锡-铈合金、酸性光亮镀锡-铈-铋合金等.化学镀Ni-P/Ni-B双层合金镀层,电镀和化学镀相结合的方法有化学镀锡和电镀锡-铈-锑合金.并归纳了各种代银镀层方法的特点,指出了代银镀层技术的发展趋势.

  3. Comparison of in situ and ex situ reduced graphene oxide reinforced electroless nickel phosphorus nanocomposite coating

    Energy Technology Data Exchange (ETDEWEB)

    Sadhir, M. Hasan; Saranya, M.; Aravind, M. [Department of Mechanical Engineering, College of Engineering Guindy, Anna University, Chennai 600025 (India); Srinivasan, A. [Departments of Chemistry, College of Engineering Guindy, Anna University, Chennai 600025 (India); Siddharthan, A., E-mail: sidharth@annauniv.edu [Department of Mechanical Engineering, College of Engineering Guindy, Anna University, Chennai 600025 (India); Department of Mechanical Engineering, CEG Campus, Anna University, Chennai 600025 (India); Rajendran, N. [Departments of Chemistry, College of Engineering Guindy, Anna University, Chennai 600025 (India)

    2014-11-30

    Highlights: • First kind of electroless nickel phosphorous (EN) reduced graphene oxide (rGO) coatings. • Change in preferential orientation of grain growth of heat treated in situ EN-rGO coating. • Better corrosion resistance of in situ EN-rGO coating. • 2 stages of reduction of Graphene (GE) to GO, during - coating and heat treatment. • Soft nature of GO for similar to polymer from low hardness of EN-GO coating. - Abstract: Electroless nickel-phosphorus (EN)–reduced graphene oxide (rGO) composite coating was carried out to compare the ex situ route of reinforcement of reduced GO in EN coating (EN-rGO) and in situ route of reinforced of rGO in EN coating (EN-GO). The coatings were characterized using X-ray diffraction (XRD) and attenuated total reflectance infrared spectroscopy (ATR-IR) for phase determination and to show the presence of reinforcement of rGO in the coatings respectively. ATR-IR spectra indicated that GO was chemically reduced in situ while deposition of EN-GO composite and thermal reduction during its heat treatment. XRD pattern of heat treated EN-GO coating show the change in preferred orientation of nickel deposit. Upon heat treatment, the hardness of EN and EN-GO and EN-rGO deposits increased while the corrosion resistance decreased except for EN-GO coating. The hardness of EN-rGO and EN-GO coating is approximately half the value of EN deposit. The electrochemical polarization studies indicated that EN-GO deposit was corrosive resistant than EN-rGO and EN deposit.

  4. Limb lengthening over plate

    Directory of Open Access Journals (Sweden)

    Ruta Kulkarni

    2012-01-01

    Conclusion: Lengthening over a plate allows early removal of external fixator and eliminates the risk of creating deep intramedullary infection as with lengthening over nail. Lengthening over plate is also applicable to children with open physis.

  5. Create Your Plate

    Medline Plus

    Full Text Available ... Planning Meals Diabetes Meal Plans Create Your Plate Gluten Free Diets Meal Planning for Vegetarian Diets Cook ... Create Your Plate Meal Planning for Vegetarian Diets Gluten Free Diets Holiday Meal Planning Cook with Heart- ...

  6. Create Your Plate

    Medline Plus

    Full Text Available ... Your Plate Gluten Free Diets Meal Planning for Vegetarian Diets Cook with Heart-Healthy Foods Holiday Meal ... Healthy Diet Create Your Plate Meal Planning for Vegetarian Diets Gluten Free Diets Holiday Meal Planning Cook ...

  7. Create Your Plate

    Medline Plus

    Full Text Available ... Yourself Fundraising & Local Events Matching Gift Fundraising Events Donate Stocks Give by ... Create Your Plate Create Your Plate is a simple and effective way to manage your blood glucose levels and lose weight. With this method, ...

  8. Create Your Plate

    Medline Plus

    Full Text Available ... Your Plate It's simple and effective for both managing diabetes and losing weight. Creating your plate lets ... Blog Online Community Site Menu Are You at Risk? Diagnosis Lower Your Risk Risk Test Alert Day ...

  9. Create Your Plate

    Medline Plus

    Full Text Available ... plates! Snap a photo and share it to social media with #CreateYourPlate . See the full gallery of ... you have an easy portion control solution that works. Last Reviewed: October 8, 2015 Last Edited: October ...

  10. Accelerated plate tectonics.

    Science.gov (United States)

    Anderson, D L

    1975-03-21

    The concept of a stressed elastic lithospheric plate riding on a viscous asthenosphere is used to calculate the recurrence interval of great earthquakes at convergent plate boundaries, the separation of decoupling and lithospheric earthquakes, and the migration pattern of large earthquakes along an arc. It is proposed that plate motions accelerate after great decoupling earthquakes and that most of the observed plate motions occur during short periods of time, separated by periods of relative quiescence.

  11. Vibration of plates

    CERN Document Server

    Chakraverty, Snehashish

    2008-01-01

    Plates are integral parts of most engineering structures and their vibration analysis is required for safe design. This work provides a comprehensive introduction to vibration theory and analysis of two-dimensional plates. It offers information on vibration problems along with a discussion of various plate geometries and boundary conditions.

  12. MyPlate

    Science.gov (United States)

    ... MyPlate What Is MyPlate? Fruits All About the Fruit Group Nutrients and Health Benefits Tips to Help You Eat Fruits Food ... lives. What Is MyPlate? Fruits All About the Fruit Group Nutrients and Health Benefits Tips to Help You Eat Fruits Food ...

  13. Electroless Deposition of Ni-Cu-P Coatings Containing Nano-Al2O3 Particles and Study of Its Corrosion Protective Behaviour in 0.5 M H2SO4

    Directory of Open Access Journals (Sweden)

    H. Ashassi-Sorkhabi

    2014-01-01

    Full Text Available Ni-Cu-P/nano-Al2O3 composite coatings are prepared on mild steel from an alkaline electroless plating bath containing different concentrations of Al2O3 nanoparticles. The protective effect of codeposited nanoparticles on the corrosion behaviour of the coatings is studied in 0.5 M H2SO4 solution. The electrochemical methods, that is, electrochemical noise (ECN, electrochemical impedance spectroscopy (EIS, and polarization measurements, are used to characterize the corrosion properties of the coatings. The results show that the inclusion of nanosized particles leads to significant improvement of corrosion resistance of the coatings. The highest corrosion resistance is obtained at 20 ppm of nanoparticles concentration in the plating bath. The ECN measurements results are in good agreement with results obtained from two other electrochemical methods after trend removal. The SEM images prove that nano-Al2O3 particles were embedded in the Ni-Cu-P matrix and are dispersed uniformly on the coating surface.

  14. 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.

  15. Corrosion Resistance of Electroless Ni-P Coating in Hydrofluoric Acid%化学镀镍-磷镀层在氢氟酸中的耐蚀性

    Institute of Scientific and Technical Information of China (English)

    李壮; 梁平

    2013-01-01

    为了改善Q 235钢在氢氟酸中的耐蚀性,采用化学镀技术在其表面制备了镍-磷镀层.采用金相显微镜对镍-磷镀层的表面形貌进行了观察,通过浸泡和电化学等方法考察了Q235钢和镍-磷镀层在氢氟酸中的耐蚀性.结果表明:所得镍磷镀层光滑、致密、平整,在氢氟酸中表现出较低的自腐蚀电流密度和较大的电荷转移电阻,可明显降低Q 235钢在氢氟酸中的腐蚀速率.%In order to improve the corrosion resistance of Q 235 steel in hydrofluoric acid, a Ni-P coating was prepared on its surface by electroless plating. The surface morphology of the coating was observed using metalloscope, and the corrosion behavior of Q 235 steel and Ni-P coating was investigated by immersion and electrochemical method. The results show that the Ni-P coating is smooth and dense, and exhibits a lower self-corrosion current density and a higher charge-transfer resistance in hydrofluoric acid, that can obviously decrease the corrosion rate of Q 235 steel in hydrofluoric acid.

  16. Insight of the interface of electroless Ni-P/SiC composite coating on aluminium alloy, LM24

    OpenAIRE

    Franco, M.; Sha, W.; Tan, V.; Malinov, S.

    2015-01-01

    Electroless nickel composite coatings with silicon carbide, SiC, as reinforcing particles deposited with Ni–P onto aluminium alloy, LM24, having zincating as under layer were subjected to heat treatment using air furnace. The changes at the interface were investigated using scanning electron microscope (SEM) and energy dispersive X-ray (EDX) to probe the chemistry changes upon heat treatment. Microhardness tester with various loads using both Knoop and Vickers indenters was used to study the ...

  17. Comparative Study on the Effects of Surfactants on the Electroless Copper Coated Solar Cell and Optimizing Its Process Parameters

    OpenAIRE

    M. Jeevarani; Elansezhian, R.

    2014-01-01

    An experimental investigation on optimizing process parameters in the electroless copper coatings on solar photovoltaic cells under specific coating conditions has been carried out and reported. Coating parameters such as pH, temperature, and surfactants concentration were varied, and corresponding coating thickness and voltage were measured. To optimize the above parameters, design of experiment was conducted using full factorial method. The pH was varied at 4 different values such as 4-5, 5...

  18. Optimization of Electroless Ni-P-W Coatings for Minimum Friction and Wear Using Grey-Taguchi Method

    OpenAIRE

    Supriyo Roy; Prasanta Sahoo

    2013-01-01

    The present experimental investigation deals with the deposition of electroless Ni-P-W coating on mild steel substrate and optimization of tribological parameters for better tribological behaviour like minimization of wear depth and coefficient of friction. Three tribological test parameters, namely, load, speed, and time, are optimized for minimum friction and wear of the coating. Friction and wear tests are carried out in a multitribotester using block on roller configuration under dry cond...

  19. Micro-scale wear characteristics of electroless Ni-P/SiC composite coating under two different sliding conditions

    OpenAIRE

    Franco, M.; Sha, W.; Malinov, S.; H. Liu

    2014-01-01

    The electroless nickel composite (ENC) with various silicon carbide contents was deposited onto aluminium alloy (LM24) substrate. The wear behaviour and the microhardness of the composite coating samples were investigated and compared with particles free and aluminium substrate samples using micro-scale abrasion tester and microhardness tester respectively. The wear scar marks and wear volume were analysed by optical microscope. The wear tracks were further studied using scanning electron mic...

  20. An Experimental Approach for Optimizing Coating Parameters of Electroless Ni-P-Cu Coating Using Artificial Bee Colony Algorithm

    OpenAIRE

    Roy, Supriyo; Sahoo, Prasanta

    2014-01-01

    This paper aims to present an experimental investigation for optimum tribological behavior (wear depth and coefficient of friction) of electroless Ni-P-Cu coatings based on four process parameters using artificial bee colony algorithm. Experiments are carried out by utilizing the combination of three coating process parameters, namely, nickel sulphate, sodium hypophosphite, and copper sulphate, and the fourth parameter is postdeposition heat treatment temperature. The design of experiment is ...

  1. Analysis of Platinum Content in Used Auto Catalytic Converter Carriers and the Possibility of its Recovery

    Directory of Open Access Journals (Sweden)

    Saternus M.

    2014-06-01

    Full Text Available Obecnie każdy wyprodukowany samochód musi być wyposażony w katalizator, w którym metale szlachetne takie jak platyna, pallad czy rod pełnią funkcje katalityczne. Czas życia katalizatorów jest ograniczony, zatem zostają one zastąpione nowymi, a stare stanowią ważne źródło platynowców. Zużyte katalizatory samochodowe przerabiane są hydrometalurgicznie lub pirometalurgicznie. Jednakże pierwszym etapem takiego przerobu powinna być analiza chemiczna. W pracy analizie na zawartość platyny poddano kilka różnych nośników katalitycznych pochodzących z różnych samochodów. Do tego celu posłużył elektronowy mikroskop skaningowy. Przedstawiono strukturę analizowanych nośników katalitycznych, ich analizę chemiczną jak również wykresy EDS (Energy Dispersive Spectrum. Przeprowadzono dyskusję wyników i możliwych metod odzysku platyny.

  2. Analysis of Platinum Content in Used Auto Catalytic Converter Carriers and the Possibility of its Recovery

    OpenAIRE

    Saternus M.; Fornalczyk A.; Cebulski J.

    2014-01-01

    Obecnie każdy wyprodukowany samochód musi być wyposażony w katalizator, w którym metale szlachetne takie jak platyna, pallad czy rod pełnią funkcje katalityczne. Czas życia katalizatorów jest ograniczony, zatem zostają one zastąpione nowymi, a stare stanowią ważne źródło platynowców. Zużyte katalizatory samochodowe przerabiane są hydrometalurgicznie lub pirometalurgicznie. Jednakże pierwszym etapem takiego przerobu powinna być analiza chemiczna. W pracy analizie na zawartość platyny poddano k...

  3. Application of Self-Assembled Monolayers to the Electroless Metallization of High Aspect Ratio Vias for Microelectronics

    Science.gov (United States)

    Bernasconi, R.; Molazemhosseini, A.; Cervati, M.; Armini, S.; Magagnin, L.

    2016-07-01

    All-wet electroless metallization of through-silicon vias (TSVs) with a width of 5 μm and a 1:10 aspect ratio was carried out. Immersion in a n-(2-aminoethyl) 3-aminopropyl-trimethoxysilane (AEAPTMS) self-assembled monolayer (SAM) was used to enhance the adhesion between the metal film and substrate. Contact angle variation and atomic force microscopy were used to verify the formation of a SAM layer. A PdCl2 solution was later used to activate the silanized substrates, exploiting the affinity of the -NH3 functional group of AEAPTMS to palladium. A nickel-phosphorus-boron electroless bath was employed to deposit the first barrier layer onto silicon. The NiPB growth rate was evaluated on flat silicon wafers, while the structure of the coating obtained was investigated via glow discharge optical emission spectroscopy. Cross-sectional scanning electron microscope observations were carried out on metallized TSVs to characterize the NiPB seed, the Cu seed layer deposited with a second electroless step, and the Cu superfilling obtained with a commercial solution. Complete filling of TSV was achieved.

  4. Inkjet catalyst printing and electroless copper deposition for low-cost patterned microwave passive devices on paper

    Science.gov (United States)

    Cook, Benjamin S.; Fang, Yunnan; Kim, Sangkil; Le, Taoran; Goodwin, W. Brandon; Sandhage, Kenneth H.; Tentzeris, Manos M.

    2013-09-01

    A scalable, low-cost process for fabricating copper-based microwave components on flexible, paper-based substrates is demonstrated. An inkjet printer is used to deposit a catalyst-bearing solution (tailored for such printing) in a desired pattern on commercially-available, recyclable, non-toxic (Teslin®) paper. The catalystbearing paper is then immersed in an aqueous copper-bearing solution to allow for electroless deposition of a compact and conformal layer of copper in the inkjet-derived pattern. Meander monopole antennas comprised of such electroless-deposited copper patterns on paper exhibited comparable performance as for antennas synthesized via inkjet printing of a commercially-available silver nanoparticle ink. However, the solution-based patterning and electroless copper deposition process avoids nozzle-clogging problems and costs associated with noble metal particle-based inks. This process yields compact conductive copper layers without appreciable oxidation and without the need for an elevated temperature, post-deposition thermal treatment commonly required for noble metal particle-based ink processes. This low-cost copper patterning process is readily scalable on virtually any substrate and may be used to generate a variety of copper-based microwave devices on flexible, paper-based substrates.

  5. Tribological Performance Optimization of Electroless Ni-B Coating under Lubricated Condition using Hybrid Grey Fuzzy Logic

    Science.gov (United States)

    Mukhopadhyay, Arkadeb; Duari, Santanu; Barman, Tapan Kumar; Sahoo, Prasanta

    2015-11-01

    Deposition of nickel coating and its alloys using electroless method has received wide acceptance by researchers and even the industries because of their excellent tribological properties. The present experimental investigation deals with the behaviour of electroless Ni-B coating under lubricated condition on a pin-on-disc tribotester. An attempt is made to minimize the friction and wear characteristics simultaneously by optimizing three test parameters i.e. the applied normal load, speed and time of sliding using grey fuzzy reasoning analysis. The friction and wear tests are carried out based on Taguchi's L27 orthogonal array of experiments. 3D surface and contour plots are generated to analyze the trends in variation of friction and wear of the deposits considering the combined effect of the design variables. Analysis of variance is done to find out the contribution of each test parameter and their interactions in controlling the friction and wear behaviour of electroless Ni-B coating. Surface morphology, phase transformation and coating composition analysis are done with the help of scanning electron microscopy, X-ray diffraction analysis and energy dispersive X-ray analysis respectively.

  6. 硫酸亚铁对化学沉积钴-铁-磷合金中的影响%The Effect of Ferrous Sulphate on the Electroless Deposition of Co-Fe-P Alloys

    Institute of Scientific and Technical Information of China (English)

    王森林; 李清华

    2004-01-01

    在以次亚磷酸钠为还原剂、硼酸为缓冲剂和柠檬酸钠为络合剂的碱性介质中,化学沉积钴-铁-磷合金和钴-磷合金.研究了沉积工艺,如 pH值和主盐CoSO4/FeSO4的摩尔比对沉积速率的影响.发现镀液中的硫酸亚铁对钴-铁-磷合金沉积有阻碍作用,以致其沉积速率比钴-磷的低.电化学极化实验表明,硫酸亚铁既影响阳极过程又影响阴极过程,它降低了两者的极化电流和极化电势.电化学实验结果与沉积速度测量结果基本相符.%Electroless deposition of Co-P alloy and Co-Fe-P alloy from an alkaline bath, containing sodium hypophosphite as a reducer, boric acid as a buffer agent and sodium citrate as a complexing agent, was investigated respectively. The effects of process parameters, such as pH of solution and metallic salt mole ratio of CoSO4/FeSO4, on the plating rate were examined. It was found that the presence of ferrous sulfate in the bath has an inhibitory effect on the alloy deposition. As a consequence, the plating rate of Co-Fe-P is lower than that of Co-P. The electrochemical polarization measurements have been carried out to examine the effect of ferrous sulphate on the cathodic or the anodic polarization process. The ferrous sulphate affects both the cathodic and anodic polarization processes, which reduces the deposition current and potential. The results of the electrochemical polarization experiments agree well with those of electroless deposition rate measurements.

  7. Automatic Licenses Plate Recognition

    OpenAIRE

    Ronak P Patel; Narendra M Patel; Keyur Brahmbhatt

    2013-01-01

    This paper describes the Smart Vehicle Screening System, which can be installed into a tollboothfor automated recognition of vehicle license plate information using a photograph of a vehicle. An automatedsystem could then be implemented to control the payment of fees, parking areas, highways, bridges ortunnels, etc. This paper contains new algorithm for recognition number plate using Morphological operation,Thresholding operation, Edge detection, Bounding box analysis for number plate extract...

  8. Fractal Plate Tectonics

    OpenAIRE

    Sornette, D.; V. F. Pisarenko

    2002-01-01

    We analyze in details the statistical significance of the claim by Bird [2002] of a power law distribution of plate areas covering the Earth and confirm that the power law with exponent 0.25 +- 0.05 is the most robust and parsimonious model for all plates, including the very largest plates, when taking into account the constraint that the plates areas must sum up to 4 pi steradians. We propose a general class of fragmentation models that rationalize this observation and discuss the implicatio...

  9. Generalized Fibonacci zone plates

    CERN Document Server

    Ke, Jie; Zhu, Jianqiang

    2015-01-01

    We propose a family of zone plates which are produced by the generalized Fibonacci sequences and their axial focusing properties are analyzed in detail. Compared with traditional Fresnel zone plates, the generalized Fibonacci zone plates present two axial foci with equal intensity. Besides, we propose an approach to adjust the axial locations of the two foci by means of different optical path difference, and further give the deterministic ratio of the two focal distances which attributes to their own generalized Fibonacci sequences. The generalized Fibonacci zone plates may allow for new applications in micro and nanophotonics.

  10. Electroless porous silicon formation applied to fabrication of boron–silica–glass cantilevers

    International Nuclear Information System (INIS)

    This work describes the characterization and optimization of anisotropic formation of porous silicon in large volumes (0.5–1 mm3) of silicon by an electroless wet etching technique. The main goal is to use porous silicon as a sacrificial volume for bulk micromachining processes, especially in cases where etching of the full wafer thickness is needed. The porous silicon volume is formed by a metal-assisted etching in a wet chemical solution composed of hydrogen peroxide (30%), hydrofluoric acid (40%) and ethanol. This paper focuses on optimizing the etching conditions in terms of maximizing the etching rate and reproducibility of the etching. In addition to that, a study of the morphology of the pore that is obtained by this technique is presented. The results from the characterization of the process are applied to the fabrication of boron–silica–glass cantilevers that serve as a platform for bio-chemical sensors. The porous silicon volume is formed in an early step of the fabrication process, allowing easy handling of the wafer during all of the micromachining processes in the process flow. In the final process step, the porous silicon is quickly etched by immersing the wafer in a KOH solution

  11. Electroless deposition of nickel and copper on titanium substrates: Characterization and application

    Energy Technology Data Exchange (ETDEWEB)

    Mahmoud, S.S. [Chemistry Department, University College for Women for Arts, Science and Education, Ain Shams University, Asmaa Fahmy, Heliopolis, Cairo (Egypt)], E-mail: drsohairr@hotmail.com

    2009-03-20

    In the present investigation nickel and copper were electroless deposited over the pre-anodized titanium substrates. The obtained deposits were characterized by X-ray diffraction (XRD) and SEM-EDX techniques. The obtained specimens were heat treated at 400 deg. C for 2 h. The heat-treated specimens were used as anodes in the process of the electrochemical degradation of Methylene Blue (MB) dye in simulated wastewater. It was shown that complete degradation of the dye is dependent primarily on the type and concentration of conductive electrolyte. The highest electrocatalytic activity was achieved in the presence of NaCl (2 g/l) and could be attributed to indirect oxidation of the investigated dye by the electrogenerated hypochlorite ions formed from the chloride ions oxidation. In addition, contribution from direct oxidation could be possible as indicated from the good results obtained in the presence of NaOH as a conductive electrolyte. Optimizing the operating conditions that ensure effective electrochemical degradation of MB dye on the titanium-modified electrodes necessitates the control of all the operating factors.

  12. Electroless formation of silver nanoaggregates: An experimental and molecular dynamics approach

    KAUST Repository

    Gentile, Francesco T.

    2014-02-20

    The ability to manipulate matter to create non-conventional structures is one of the key issues of material science. The understanding of assembling mechanism at the nanoscale allows us to engineer new nanomaterials, with physical properties intimately depending on their structure.This paper describes new strategies to obtain and characterise metal nanostructures via the combination of a top-down method, such as electron beam lithography, and a bottom-up technique, such as the chemical electroless deposition. We realised silver nanoparticle aggregates within well-defined patterned holes created by electron beam lithography on silicon substrates. The quality characteristics of the nanoaggregates were verified by using scanning electron microscopy and atomic force microscopy imaging. Moreover, we compared the experimental findings to molecular dynamics simulations of nanoparticles growth. We observed a very high dependence of the structure characteristics on the pattern nanowell aspect ratio. We found that high-quality metal nanostructures may be obtained in patterns with well aspect ratio close to one, corresponding to a maximum diameter of 50 nm, a limit above which the fabricated structures become less regular and discontinuous. When regular shapes and sizes are necessary, as in nanophotonics, these results suggest the pattern characteristics to obtain isolated, uniform and reproducible metal nanospheres. © 2014 Taylor & Francis.

  13. The Characterization of Al Bond Pad Surface Treatment in Electroless Nickel Immersion Gold (ENIG Deposition

    Directory of Open Access Journals (Sweden)

    M. K. M. Arshad

    2007-01-01

    Full Text Available This study reports a number of experiments that were designed to characterize aluminum bond pad surfaces prior to electroless nickel immersion gold (ENIG. In the ENIG process, aluminum bond pads need special treatment to achieve successful nickel deposition and provide reliable interconnection of under bump metallurgy in advanced packaging. During this treatment process, the aluminum pad was cleaned, activated and then coated with a layer of zinc. Systematic study was carried out to determine the best parameters, through multiple and various exposure times of the zincation process and zincation solution concentration effect on the Ni/Au surface roughness and aluminum dissolution rate on the bond pad during multiple zincation process. The ball shear strength was evaluated between eutectic 37Pb/63Sn solder ball and under bump metallurgy (UBM interfaces across multiple zincation process. Scanning Electron Microscope (SEM, Energy Dispersive X-Ray (EDX, Atomic Force Microscopy (AFM, Focused Ion Beam (FIB and ball shear tester were used as analytical tools. The results suggest that the multiple zincation process consistently produces a smoother surface of ENIG UBM and consequently provides a better shear strength.

  14. Superhydrophobic surfaces via electroless displacement of nanometric Cu layers by Ag{sup +}

    Energy Technology Data Exchange (ETDEWEB)

    Brenier, R., E-mail: roger.brenier@lpmcn.univ-lyon1.fr [Universite de Lyon, Universite Lyon1, Laboratoire PMCN, CNRS, UMR 5586, F69622 Villeurbanne Cedex (France); Ramos, S.M.M.; Montchanin, M. [Universite de Lyon, Universite Lyon1, Laboratoire PMCN, CNRS, UMR 5586, F69622 Villeurbanne Cedex (France)

    2009-05-30

    This paper explores the possibility of making hydrophobic and superhydrophobic surfaces from electroless displacement of Cu by Ag{sup +}, in the case where Cu oxidation is limited owing to Cu layers of nanometric thicknesses. The morphology of the Ag layers is studied by scanning electron microscopy for Cu thicknesses between 10 and 80 nm. The mapping of the elemental content of the layers by electron dispersive X-ray analysis also has been used to clarify the particle growing by diffusion limited aggregation. It is shown that the average size and the shape complexity of the Ag particles increase with the Cu thickness. The addition of dimethyl sulfoxide in the Ag{sup +} aqueous solution improves the surface homogeneity, increases the particle density and decreases their sizes. The wetting behaviour of the surfaces, after grafting with octadecanethiol, has been studied from measurements of the contact angles of a drop of water. According to the thickness of the initial Cu layer and the morphology of the Ag layer, contact angles range between 110{sup o} and 154{sup o}. Superhydrophobic surfaces are obtained from 80 nm thick Cu layers.

  15. Nanostructured core-shell Ni deposition on SiC particles by alkaline electroless coating

    Science.gov (United States)

    Uysal, M.; Karslioğlu, R.; Alp, A.; Akbulut, H.

    2011-10-01

    In this study, core-shell nanostructured nickel formation on silicon carbide (SiC) ceramic powders was achieved through the electroless deposition method using alkaline solutions. To produce a nano core-shell Ni deposition on the SiC surfaces, process parameters such as pH values, the type of reducer material, deposition temperature, stirring rate and activation procedure among others were determined. Full coverage of core-shell nickel structures on SiC surfaces was achieved with a grain size of between 100 and 300 nm, which was approximately the same deposition thickness on the SiC surfaces. The surface morphology of the coated SiC particles showed a homogenous distribution of nanostructured nickel grains characterized by scanning electron microscopy and X-ray diffraction techniques. The nanostructures of the crystalline Ni coatings were observed to be attractive for achieving both good bonding and dense structure. The thin core shell-structure of Ni on the SiC surfaces was assessed as a beneficial reinforcement for possible metal matrix composite manufacturing.

  16. Palladium-free catalytic electroless copper deposition on bamboo fabric: Preparation, morphology and electromagnetic properties

    Science.gov (United States)

    Lu, Yinxiang; Liang, Qian; Xue, Longlong

    2012-03-01

    Bamboo fabric is subjected to solvent treatment with 3-mercaptopropyltrimethoxysilane (MPTS) before metal deposition. Raman and IR analyses indicate that MPTS is successfully grafted on the fabric. Copper is deposited on the pretreated fabric by a palladium-free catalytic electroless process, and then copper/bamboo fabric (Cu/BF) composite is obtained. SEM (scanning electron microscopy) observation reveals that copper is uniformly covered on the fabric. Chemical composition and crystal structure of the composite are detected by EDX (energy-dispersive X-ray analysis), XPS (X-ray photoelectron spectroscopy) and XRD (X-ray diffraction) measurements, peaks for Cu0 are found in these patterns. The water absorption ratio for the title composite is about 162% by immersion in water, or 8.9% by putting in an environmental condition (humidity of 65 ± 2%). The Cu/BF composite is firm and can pass a Scotch®-tape peel adhesion test. The electromagnetic interference (EMI) shielding effectiveness (SE) of the composite (copper on fabric: 39 g/m2) is more than 48 dB at frequency ranging from 0.2 to1000 MHz.

  17. Effect of W addition on the electroless deposited NiP(W) barrier layer

    International Nuclear Information System (INIS)

    Electroless deposition of NiP, NiWP thin film on p-type Si as the barrier layer to prevent the diffusion of Cu into Si was investigated. The thermal stability of the Si/Ni(W)P/Cu layers were evaluated by measuring the changes of resistance of the samples after annealed at various temperatures. XRD was applied to detect the formation of Cu3Si and evaluate the barrier performance of the layers. The results of XRD of the stacked Si/NiP/Cu, Si/NiWP-1/Cu, Si/NiWP–2/Cu films reveal that Cu atom could diffuse through NiP barrier layer at 450 °C, Cu could hardly diffuse through NiWP layer at 550 °C. This means that with W added in the layer, the barrier performance is improved. Although the resistance of Si/NiWP-1 and Si/NiWP-2 are higher than that of Si/NiP, the resistance of stacked layers of Si/NiWP-1/Cu and Si/NiWP–2/Cu are close to that of Si/NiP/Cu. This means that using NiWP as barrier layer is acceptable.

  18. Comparison of in situ and ex situ reduced graphene oxide reinforced electroless nickel phosphorus nanocomposite coating

    Science.gov (United States)

    Sadhir, M. Hasan; Saranya, M.; Aravind, M.; Srinivasan, A.; Siddharthan, A.; Rajendran, N.

    2014-11-01

    Electroless nickel-phosphorus (EN)-reduced graphene oxide (rGO) composite coating was carried out to compare the ex situ route of reinforcement of reduced GO in EN coating (EN-rGO) and in situ route of reinforced of rGO in EN coating (EN-GO). The coatings were characterized using X-ray diffraction (XRD) and attenuated total reflectance infrared spectroscopy (ATR-IR) for phase determination and to show the presence of reinforcement of rGO in the coatings respectively. ATR-IR spectra indicated that GO was chemically reduced in situ while deposition of EN-GO composite and thermal reduction during its heat treatment. XRD pattern of heat treated EN-GO coating show the change in preferred orientation of nickel deposit. Upon heat treatment, the hardness of EN and EN-GO and EN-rGO deposits increased while the corrosion resistance decreased except for EN-GO coating. The hardness of EN-rGO and EN-GO coating is approximately half the value of EN deposit. The electrochemical polarization studies indicated that EN-GO deposit was corrosive resistant than EN-rGO and EN deposit.

  19. Novel electroless copper deposition on carbon fibers with environmentally friendly processes.

    Science.gov (United States)

    Byeon, Jeong Hoon; Kim, Jang-Woo

    2010-08-15

    A novel electroless deposition (ELD) of copper (Cu) on carbon fibers (CFs) with environmentally friendly processes, silver (Ag) aerosol activation and subsequent nonformaldehyde Cu ELD, was developed. Spark-generated Ag aerosol nanoparticles (approximately 10 nm in mode diameter) were deposited (48.4 microg Ag/g CF in activation intensity) onto the surfaces of CFs. After annealing (at 220 degrees C in a nitrogen atmosphere), the catalytically activated CFs were placed into a solution for Cu ELD (at 82 degrees C). Homogeneous Cu coating (approximately 5.1 nm/min) on CFs was achieved with 90 min of deposition and the corresponding mass deposition rate and Cu grain size for 30-90 min of deposition had ranges of 0.25-1.14 mg Cu/g CF-min and 14.8-37.2 nm, respectively. The porosity of CFs decreased by depositing the Cu for 30-90 min, and the specific surface area and pore volume of CFs decreased from 1536 to 1399 m(2)/g and from 0.65 to 0.57 cm(3)/g, respectively. PMID:20621827

  20. Fabricating and improving properties of copper matrix nanocomposites by electroless copper-coated MWCNTs

    Science.gov (United States)

    Alizadeh Sahraei, Abolfazl; Fathi, Alireza; Besharati Givi, Mohammad Kazem; Pashaei, Mohammad Hadi

    2014-09-01

    In this study, copper (Cu) nanocomposites reinforced by coated multiwall carbon nanotubes (MWCNTs) have been fabricated with different weight fractions of MWCNT. In the first step, the as-received MWCNTs were coated with Cu using electroless deposition process. In the next step, combination of sonication and ball milling (with two milling time of 1.5 and 3 h) was used for preparing MWCNT/Cu composite powders. Finally, the disk-shaped specimens were sintered by hot-press sintering machine. Characterization of sintered nanocomposites revealed that increasing milling time led to improved mechanical properties, but higher defect density on the MWCNT sidewalls is obtained which is especially undesirable for electrical properties of nanocomposite. Our results indicated that simultaneous improvements of interface reactions and distribution uniformity of MWCNTs and Cu are key factors for obtaining enhanced mechanical properties. Accordingly, enhancement of up to ~150 and ~86 % in microhardness compared to pure Cu and 1 wt% as-received MWCNT/Cu was achieved by addition of 1 wt% Cu-coated MWCNT. On the contrary, existence of oxygen atoms in the Cu and coated MWCNT interface (from functional groups and deposited copper oxide) obstructs considerable improvement of electrical resistivity compared to as-received MWCNT/Cu nanocomposites.

  1. Electroless deposition of metal nanoparticles on graphene with substrate-assisted techniques

    Science.gov (United States)

    Zaniewski, Anna M.; Trimble, Christie J.; Meeks, Veronica; Nemanich, Robert J.

    2015-03-01

    We present the electroless reduction of solution-based metal ions for nanoparticle deposition on a variety of substrates. The substrates include graphene-coated metals, insulators, doped semiconductors, and patterned ferroelectrics. We find that the metal ions are spontaneously reduced on a wide variety of graphene substrates, and the substrates play a large role in the nanoparticle coverage. For example, the reduction of gold chloride to gold nanoparticles on graphene/lithium niobate results in 3% nanoparticle coverage compared to 20% coverage on graphene/silicon and 60% on graphene/copper. Given that the work function of graphene is approximately 4.4eV, the Fermi level is -0.1 V vs the normal hydrogen electrode (NHE). Since the reduction potential of gold chloride is +1.002 V, the spontaneous transfer of electrons from the graphene to the metal ion is energetically favorable. However, we find substrates with similar work functions nevertheless result in varied deposition rates, which we attribute to electron availability. We also find that patterned ferrolectrics can be used as a template for patterned nanoparticle deposition, with and without graphene. This work is supported by the National Science Foundation under Grant # DMR-1206935.

  2. Electroless deposition of conformal nanoscale iron oxide on carbon nanoarchitectures for electrochemical charge storage.

    Science.gov (United States)

    Sassin, Megan B; Mansour, Azzam N; Pettigrew, Katherine A; Rolison, Debra R; Long, Jeffrey W

    2010-08-24

    We describe a simple self-limiting electroless deposition process whereby conformal, nanoscale iron oxide (FeO(x)) coatings are generated at the interior and exterior surfaces of macroscopically thick ( approximately 90 microm) carbon nanofoam paper substrates via redox reaction with aqueous K(2)FeO(4). The resulting FeO(x)-carbon nanofoams are characterized as device-ready electrode structures for aqueous electrochemical capacitors and they demonstrate a 3-to-7 fold increase in charge-storage capacity relative to the native carbon nanofoam when cycled in a mild aqueous electrolyte (2.5 M Li(2)SO(4)), yielding mass-, volume-, and footprint-normalized capacitances of 84 F g(-1), 121 F cm(-3), and 0.85 F cm(-2), respectively, even at modest FeO(x) loadings (27 wt %). The additional charge-storage capacity arises from faradaic pseudocapacitance of the FeO(x) coating, delivering specific capacitance >300 F g(-1) normalized to the content of FeO(x) as FeOOH, as verified by electrochemical measurements and in situ X-ray absorption spectroscopy. The additional capacitance is electrochemically addressable within tens of seconds, a time scale of relevance for high-rate electrochemical charge storage. We also demonstrate that the addition of borate to buffer the Li(2)SO(4) electrolyte effectively suppresses the electrochemical dissolution of the FeO(x) coating, resulting in <20% capacitance fade over 1000 consecutive cycles. PMID:20731433

  3. Synthesis, characterization and application of electroless metal assisted silicon nanowire arrays

    Science.gov (United States)

    Sahoo, Sumanta Kumar; Marikani, Arumugam

    2015-12-01

    Vertically aligned silicon nanowire arrays (SiNWs) have been synthesized by electroless metal deposition process. The fabricated SiNWs have an average diameter of 75 nm and 3.5-4.0 μm length, as confirmed from scanning electron microscopy. A characteristic asymmetric peak broadening at 520 cm-1 from Raman spectroscopy was obtained for the SiNWs as compared to the bulk silicon crystal due to phonon confinement. The as-prepared SiNWs exhibit good electron field-emission properties with turn-on field of about 8.26 V μm-1 at a current density of 4.9 μA cm-2. The SiNWs was functionalized by coating with a thin gold metallic film for 60 s, and then used as bio-probe for the detection of bovine serum albumin (BSA) protein molecules. From the linear sweep voltammetry analysis, the Au coated SiNWs, exhibit linear response to the BSA analyte with increase in concentration. The minimum detection limit of the protein molecule was calculated of about 1.16 μM by the as-synthesized SiNWs probe.

  4. Electrochemical and structural properties of electroless Ni-P-SiC nanocomposite coatings

    Energy Technology Data Exchange (ETDEWEB)

    Farzaneh, Amir [Department of Materials Science and Engineering, Faculty of Engineering, Shahid Bahonar University of Kerman (Iran, Islamic Republic of); Department of Materials Science and Engineering, Faculty of Mechanical Engineering, University of Tabriz (Iran, Islamic Republic of); Mohammadi, Maysam, E-mail: maysam.mohammadi84@gmail.com [High Technology and Environmental Sciences, International Center for Science, Materials Research Institute, Kerman (Iran, Islamic Republic of); Ehteshamzadeh, Maryam [Department of Materials Science and Engineering, Faculty of Engineering, Shahid Bahonar University of Kerman (Iran, Islamic Republic of); High Technology and Environmental Sciences, International Center for Science, Materials Research Institute, Kerman (Iran, Islamic Republic of); Mohammadi, Farzad [Department of Materials Engineering, The University of British Columbia, Vancouver, BC (Canada)

    2013-07-01

    Silicon carbide (SiC) nanoparticles were co-deposited with nickel-phosphorous (Ni-P) coatings through electroless deposition process. The effects of annealing temperature and SiC contents on properties of the coatings were investigated. Corrosion performance of the coatings was examined using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). X-ray diffraction and Scanning Electron Microscopy (SEM) were employed for structural and morphological studies, respectively. It was shown that the structure of the as-deposited Ni-P-SiC nanocomposite coating was amorphous, and changed to the nickel crystal, nickel phosphide (Ni{sub 3}P) and silicide compounds (Ni{sub x}Si{sub y}) with heat treatment. Addition of the SiC concentration in the coating bath affected both composition and morphology of the coating. Presence of SiC nanoparticles in the Ni-P coating enhanced the corrosion resistance of the coating. Higher SiC contents, however, negatively affected the corrosion behavior of the coatings. Heat treatment also improved the corrosion resistance of the Ni-P-SiC coating. Annealing at 400 °C decreased the corrosion current density of the coating by approximately 60%.

  5. Crystallization mechanism and corrosion property of electroless nickel phosphorus coating during intermediate temperature oxidation

    Science.gov (United States)

    Sribalaji, M.; Arunkumar, P.; Babu, K. Suresh; Keshri, Anup Kumar

    2015-11-01

    Electroless Ni-P coating was deposited on steel substrate and the effect of intermediate temperature oxidation on crystallization mechanism and corrosion properties of the coating was investigated. Ni-P coatings were annealed at three different temperatures, viz. 200 °C, 400 °C and 600 °C for 2 h in air. Formation of nickel oxide (NiO) was observed in the coating upon annealing beyond the crystallization temperature (330 °C). Crystallization mechanism provided insight about the step by step formation of long range ordered Ni,Ni3P and NiO phases.Improvement in the corrosion resistance of Ni-P coating compared to bare steel was found to be ∼21% on annealing at 400 °C in air which gradually increased to ∼31% on annealing the coating at 600 °C in air. Increasedcorrosion resistance at 400 °C annealed coating was attributed to the formation of crystalline Ni and Ni3P phases. Two simultaneously effects have been identified for the increased corrosion resistance of the coating annealed at 600 °C in air. (a) Formation of NiO layer which acts as a passivation layer and protects the underlying P enriched layer and (b) absence of an interdiffusion layer from substrate to coating.

  6. Synthesis and characterization of electroless Ni–P coated graphite particles

    Indian Academy of Sciences (India)

    M Ananth Kumar; Ramesh Chandra Agarwala; Vijaya Agarwala

    2008-10-01

    Electroless alkaline bath is used to coat Ni–P graphite particles of average size, 150 m. Amorphous nickel and graphite phases are observed in X-ray diffraction of the coated particles. The crystallite size from diffraction peaks is found to be 9.56 nm. The microstructural studies are carried out with field emission scanning electron microscope (SEM) on the uncoated and coated graphite particles. Uncoated particles showed irregular and fractured surfaces while the surface of coated particles revealed the presence of Ni–P globules. Sizes of Ni–P globules are observed to be in the range 175–250 nm. The presence of Ni and P are confirmed by the energy dispersive spectrometer results. The effect of coating bath composition is studied and an increasing trend in deposition is observed up to 50 gl–1 of stabilizer as well as up to 20 gl–1 of the reducing agent, however, the trend reverses afterwards. The phenomena of nucleation and growth of the Ni–P layer over the graphite surface have been demonstrated through SEM studies and a model has been proposed to demonstrate the growth mechanism of Ni–P globules.

  7. Create Your Plate

    Medline Plus

    Full Text Available ... In Memory In Honor Become a Member En Español Type 1 Type 2 About Us Online Community ... Page Text Size: A A A Listen En Español Create Your Plate Create Your Plate is a ...

  8. Blue Willow Story Plates

    Science.gov (United States)

    Fontes, Kris

    2009-01-01

    In the December 1997 issue of "SchoolArts" is a lesson titled "Blue Willow Story Plates" by Susan Striker. In this article, the author shares how she used this lesson with her middle-school students many times over the years. Here, she describes a Blue Willow plate painting project that her students made.

  9. Create Your Plate

    Medline Plus

    Full Text Available ... and Type 2 Diabetes Know Your Rights Employment Discrimination Health Care Professionals Law Enforcement Driver's License For ... critical diabetes research and support vital diabetes education services that improve the lives of those with ... plates! Snap a photo and share it to social media with #CreateYourPlate . See the full gallery of ...

  10. Moldagem por injeção da PA 6.6 em moldes de estereolitografia metalizados com Ni-P pelo processo electroless Injection molding of PA 6.6 in stereolithography moulds coated with electroless Ni-P

    Directory of Open Access Journals (Sweden)

    Diovani C. Lencina

    2007-06-01

    Full Text Available A fabricação de moldes por técnicas de prototipagem rápida, como a estereolitografia (SL, é considerada uma importante tecnologia no auxílio ao desenvolvimento de produtos de plástico moldados por injeção. Embora esta tecnologia se mostre vantajosa, a vida útil dos moldes pode ser bastante reduzida em decorrência, por exemplo, de forte adesão entre o polímero injetado e o material do molde SL. Neste trabalho é investigado o uso da técnica de recobrimento metálico com Ni-P por deposição electroless sobre moldes de injeção, fabricados por SL com a resina DSM SOMOS 7110®. Foram comparados resultados de moldagem de PA6.6 em moldes fabricados com e sem recobrimento metálico evidenciando a possibilidade de utilizar a técnica de metalização como alternativa para a moldagem deste material em moldes SL, uma vez que a vida útil foi superior.Manufacturing of moulds by rapid prototyping processes, such as stereolithography (SL, is considered an important technology to aid the development of injection moulding plastic products. Although this technology shows significant advantages, the lifetime of moulds may be drastically be reduced due to strong adhesion between the injected polymer and the material of the SL mould. This work investigates the use of Ni-P metal coating obtained by electroless deposition on SL moulds manufactured with the resin DSM SOMOS 7110. Specimens of PA6.6 have been injected into SL moulds manufactured with and without metal coating. The results showed that the electroless metal coating process can be an appropriate alternative to allow moulding of small series of PA6.6 parts in SL moulds.

  11. Fabrication of a micro-porous Ti–Zr alloy by electroless reduction with a calcium reductant for electrolytic capacitor applications

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Tatsuya, E-mail: kiku@eng.hokudai.ac.jp [Faculty of Engineering, Hokkaido University, N13-W8, Kita-ku, Sapporo, Hokkaido 060-8628 (Japan); Yoshida, Masumi [Faculty of Engineering, Hokkaido University, N13-W8, Kita-ku, Sapporo, Hokkaido 060-8628 (Japan); Taguchi, Yoshiaki [Graduate School of Chemical Science and Engineering, Hokkaido University, N13-W8, Kita-ku, Sapporo, Hokkaido 060-8628 (Japan); Habazaki, Hiroki; Suzuki, Ryosuke O. [Faculty of Engineering, Hokkaido University, N13-W8, Kita-ku, Sapporo, Hokkaido 060-8628 (Japan)

    2014-02-15

    Highlights: • A metallic Ti–Zr alloy was obtained by electroless reduction for capacitor applications. • The reduction mechanisms were studied by SEM, XRD, EPMA, and an oxygen analyzer. • The alloy was obtained by electroless reduction in the presence of excess calcium reductant. • A micro-porous Ti–Zr alloy was successfully obtained. • The alloy has a low oxygen content and a large surface area. -- Abstract: A metallic titanium and zirconium micro-porous alloy for electrolytic capacitor applications was produced by electroless reduction with a calcium reductant in calcium chloride molten salt at 1173 K. Mixed TiO{sub 2}–70 at%ZrO{sub 2} oxides, metallic calcium, and calcium chloride were placed in a titanium crucible and heated under argon atmosphere to reduce the oxides with the calcium reductant. A metallic Ti–Zr alloy was obtained by electroless reduction in the presence of excess calcium reductant and showed a micro-porous morphology due to the sintering of each of the reduced particles during the reduction. The residual oxygen content and surface area of the reduced Ti–Zr alloy decreased over time during the electroless reduction. The element distributions were slightly different at the positions of the alloy and were in the composition range of Ti-69.3 at% to 74.3 at%Zr. A micro-porous Ti–Zr alloy with low oxygen content (0.20 wt%) and large surface area (0.55 m{sup 2} g{sup −1}) was successfully fabricated by electroless reduction under optimal conditions. The reduction mechanisms of the mixed and pure oxides by the calcium reductant are also discussed.

  12. SiC颗粒尺寸对镁合金化学镀Ni-P-SiC层摩擦学性能的影响%Effect of Silicon Carbide Particle Size on Wear Resistance of Electroless Nickel - Phosphorous - Silicon Carbide Composite Coatings of Magnesium Alloy Substrate

    Institute of Scientific and Technical Information of China (English)

    马洪涛; 戈晓岚

    2013-01-01

    Ni - P - SiC composite coatings were prepared on Mg alloy substrate via electroless plating while SiC particulates with different sizes (nanoscale, sub - micron and micron) were separately introduced as reinforcing phases into the electroless plating bath. The effect of SiC size on the morphology, composition, hardness and wear resistance of as - obtained Ni - P -SiC composite coatings was investigated with a scanning electron microscope, an energy dispersive spectrometer, a hardness meter, and a friction and wear tester. It was found that Ni-P-SiC composite coating reinforced with sub - micron SiC particles contained uniform and fine surface crystal clusters, and showed the highest hardness and the best wear resistance (with a friction coefficient of 0.33).%为了探讨SiC颗粒尺寸对Ni-P-SiC化学镀层摩擦学性能的影响,在Ni-P化学镀液中分别加入纳米、亚微米、微米SiC颗粒制备Ni-P-SiC复合镀层,采用扫描电镜(SEM)、能谱仪、硬度计、摩擦磨损试验机等研究了SiC颗粒尺寸对Ni-P-SiC镀层形貌、成分、硬度、耐磨性的影响.结果表明:亚微米SiC制成的复合镀层表面晶簇均匀,晶胞细小;亚微米SiC强化镀层的效果最理想,镀层硬度最大,摩擦系数约为0.33,耐磨性最好.

  13. Tribological and Corrosion Properties of Nickel/TiC Bilayered Coatings Produced by Electroless Deposition and PACVD

    Science.gov (United States)

    Shanaghi, Ali; Chu, Paul K.

    2016-10-01

    Ni/TiC bilayered coatings are deposited on hot-working steel (H11) by plasma-assisted chemical vapor deposition and electroless technique. The TiC layer is deposited at 490 °C using a gas mixture of TiCl4, CH4, H2, and Ar, and a dense nanostructured TiC coating with minimum excessive carbon phases and low chlorine concentration is produced. The effects of the Ni intermediate layer on the microstructure, tribology, and corrosion behavior of the nanostructured TiC coating are investigated. The friction coefficient of the Ni/TiC bilayered coating (Ni thickness = 4 µm) at 500 cycles is much smaller than that of the coating without the Ni intermediate layer. The smallest friction coefficient is about 0.2, and the hardness values of the Ni/TiC bilayered samples with three different Ni layer thicknesses of 2, 4, and 6 µm are 2534, 3070, and 2008 Hv, respectively. The wear mechanism of the Ni/TiC bilayered coatings is abrasive induced by plastic deformation and fatigue during the sliding process. The smaller groove width on the 4-µm electroless nickel-Ni3P/TiC bilayered coating correlates with the larger H/E ratio and the 4-µm nickel/TiC bilayered sample shows the better wear resistance. The polarization resistance of the 6-µm electroless nickel-Ni3P/TiC coating in 0.05 M NaCl and 0.5 M H2SO4 increases by about 8 and 15 times, respectively. The Ni intermediate layer increases the toughness of the coating and adhesion between the hard coating and steel substrate thereby enhancing the tribological properties and corrosion resistance.

  14. Characterization of the metal–semiconductor interface of gold contacts on CdZnTe formed by electroless deposition

    International Nuclear Information System (INIS)

    Fully spectroscopic x/γ-ray imaging is now possible thanks to advances in the growth of wide-bandgap semiconductors. One of the most promising materials is cadmium zinc telluride (CdZnTe or CZT), which has been demonstrated in homeland security, medical imaging, astrophysics and industrial analysis applications. These applications have demanding energy and spatial resolution requirements that are not always met by the metal contacts deposited on the CdZnTe. To improve the contacts, the interface formed between metal and semiconductor during contact deposition must be better understood. Gold has a work function closely matching that of high resistivity CdZnTe and is a popular choice of contact metal. Gold contacts are often formed by electroless deposition however this forms a complex interface. The prior CdZnTe surface preparation, such as mechanical or chemo-mechanical polishing, and electroless deposition parameters, such as gold chloride solution temperature, play important roles in the formation of the interface and are the subject of the presented work. Techniques such as focused ion beam (FIB) cross section imaging, transmission electron microscopy (TEM), energy dispersive x-ray spectroscopy (EDS), x-ray photoelectron spectroscopy (XPS) and current  −  voltage (I–V) analysis have been used to characterize the interface. It has been found that the electroless reaction depends on the surface preparation and for chemo-mechanically polished (1 1 1) CdZnTe, it also depends on the A/B face identity. Where the deposition occurred at elevated temperature, the deposited contacts were found to produce a greater leakage current and suffered from increased subsurface voiding due to the formation of cadmium chloride. (paper)

  15. Computational valve plate design

    Science.gov (United States)

    Kalbfleisch, Paul

    Axial piston machines are widely used in many industries for their designs compactness, flexibility in power transfer, variable flow rate, and high efficiencies as compared to their manufacturing costs. One important component of all axial piston machines that is a very influential on the performance of the unit is the valve plate. The aim of this research is to develop a design methodology that is general enough to design all types of valve plates and the simple enough not to require advanced technical knowledge from the user. A new style of valve plate designs has been developed that comprehensively considers all previous design techniques and does not require significant changes to the manufacturing processes of valve plates. The design methodology utilizes a previously developed accurate computer model of the physical phenomenon. This allows the precise optimization of the valve plate design through the use of simulations rather than expensive trial and error processes. The design of the valve plate is clarified into the form of an optimization problem. This formulation into an optimization problem has motivated the selection of an optimization algorithm that satisfies the requirements of the design. The proposed design methodology was successfully tested in a case study in the shown to be very successful in improving required performance of the valve plate design.

  16. Plate heat exchanger

    International Nuclear Information System (INIS)

    In a plate heat exchanger required to handle corrosive, toxic or radioactive fluids, wherein each plate has a peripheral recess or like formation adapted for receiving an elastomeric gasket, the plates are welded together in pairs by the method comprising the steps of inserting into the gasket recess of a first plate of said pair a metal packing piece and welding the second place (e.g. by a laser or electron beam weld running along the base of the recess) superimposing a second plate on to the first in contact with the packing piece and welding the second plate to the packing piece (e.g. by a laser or electron beam weld). The packing piece may be of hollow or solid cross section and is preferably of the same material (e.g. titanium or stainless steel) as the plates. In use a service fluid in heat exchange with the said corrosive etc. fluid is confined by peripheral and normally elastomeric gaskets. (author)

  17. 铈对化学镀Ni-Fe-Co-P镀液及镀层性能的影响%Effects of Cerium on Electroless Ni-Fe-Co-P Bath and Properties of the Coating

    Institute of Scientific and Technical Information of China (English)

    贾瑛; 冯程; 张颖

    2012-01-01

    Based on the established bath of electroless Ni-Fe-Co-P plating, cerium nitrate was added to the bath, and a Ni-Fe-Co-P-Ce alloy coating was prepared on polyester fibers. The effects of the mass concentration of cerium nitrate on the deposition rate, surface morphology,composition,corrosion resistance of the coating were discussed,obtaining an optimal mass concentration as 0. 4 g/L.%在确定化学镀Ni-Fe-Co-P镀液配方的基础上,往镀液中加入硝酸铈,在涤沦织物上制备Ni-Fe-Co-P-Ce合金镀层.讨论了硝酸铈的质量浓度对镀层的沉积速率、表面形貌、成分及耐蚀性能等的影响,得出其最佳的质量浓度为0.4 g/L.

  18. Anisotropic SmCo5/FeCo core/shell nanocomposite chips prepared via electroless coating

    OpenAIRE

    Narayan Poudyal; Kinjal Gandha; Kevin Elkins; J. Ping Liu

    2015-01-01

    We report the preparation of anisotropic SmCo5/FeCo core/shell nanocomposite chip-like particles via an electroless coating process. The anisotropic SmCo5 nanoscale chips were first prepared by surfactant-assisted ball milling then coated with soft magnetic FeCo using cobalt sulfate (CoSO4.7H2O) and iron sulfate (FeSO4.7H2O) as metal precursors in presence of complexing agents. The influence of the soft-phase coating on the magnetic properties of the nanocomposite particles has been studied. ...

  19. The Microstructure of Ni Layer on Single-Walled Carbon Nanotubes Prepared by an Electroless Coating Process

    OpenAIRE

    Weixue Li; Hui Jin; Yuan Hao; Tijun Chen; Jianfeng Dai; Qing Wang

    2011-01-01

    The single-walled carbon nanotubes (SWNTs, diameter: 2~3 nm), which were obtained in the suspension of purification solution, with Ni-P coating layers were obtained by an electroless deposition process. The SWNTs before and after coating were characterized by transmission electron microscopy (TEM) and energy dispersive spectrometry (EDS). An Ni-P layer on individual nanotube with thickness of 20 nm can be obtained after the deposition process. The X-ray diffraction (XRD) and selected area ele...

  20. EFFECT OF pH ON ELECTROLESS Ni-P COATING OF CONDUCTIVE AND NON-CONDUCTIVE MATERIALS

    OpenAIRE

    Subrata Roy; Moniruzzaman, M.

    2011-01-01

    Electroless nickel-phosphorus (Ni-P) coating of carbon steel as well as a polypropylene substrate was conducted using sodium hypophosphite as a reducing agent in alkaline media. The influence of pH on coating appearances and the properties of the coatings for both steel and the polypropylene substrate were studied. A nickel-phosphorus coating of good appearance was obtained in the pH range between 5.5 and 12.5 on the carbon steel substrate and between 8.5 and 12 on the polypropylene substrate...

  1. Anisotropic elastic plates

    CERN Document Server

    Hwu, Chyanbin

    2010-01-01

    As structural elements, anisotropic elastic plates find wide applications in modern technology. The plates here are considered to be subjected to not only in plane load but also transverse load. In other words, both plane and plate bending problems as well as the stretching-bending coupling problems are all explained in this book. In addition to the introduction of the theory of anisotropic elasticity, several important subjects have are discussed in this book such as interfaces, cracks, holes, inclusions, contact problems, piezoelectric materials, thermoelastic problems and boundary element a

  2. Plate removal following orthognathic surgery.

    Science.gov (United States)

    Little, Mhairi; Langford, Richard Julian; Bhanji, Adam; Farr, David

    2015-11-01

    The objectives of this study are to determine the removal rates of orthognathic plates used during orthognathic surgery at James Cook University Hospital and describe the reasons for plate removal. 202 consecutive orthognathic cases were identified between July 2004 and July 2012. Demographics and procedure details were collected for these patients. Patients from this group who returned to theatre for plate removal between July 2004 and November 2012 were identified and their notes were analysed for data including reason for plate removal, age, smoking status, sex and time to plate removal. 3.2% of plates were removed with proportionally more plates removed from the mandible than the maxilla. 10.4% of patients required removal of one or more plate. Most plates were removed within the first post-operative year. The commonest reasons for plate removal were plate exposure and infection. The plate removal rates in our study are comparable to those seen in the literature.

  3. Novel Investigation on Nanostructured Multilayer and Functionally Graded Ni-P Electroless Coatings on Stainless Steel

    Science.gov (United States)

    Anvari, S. R.; Monirvaghefi, S. M.; Enayati, M. H.

    2015-06-01

    In this study, step-wise multilayer and functionally graded Ni-P coatings were deposited with electroless in which the content of phosphorus and nickel would be changed gradually and step-wise through the thickness of the coatings, respectively. To compare the properties of these coatings with Ni-P single-layer coatings, three types of coatings with different phosphorus contents were deposited. Heat treatment of coatings was performed at 400 °C for 1 h. The microstructure and phase transformation of coatings were characterized by SEM/EDS, TEM, and XRD. The mechanical properties of coatings were studied by nanoindentation test. According to the results of the single-layer coatings, low P coating had the maximum hardness and also the ratio of hardness ( H) to elasticity modulus ( E) for the mentioned coating was maximum. In addition, low and medium P coatings had crystalline and semi-crystalline structure, respectively. The mentioned coatings had texture and after heat treatment their texture didn't change. While high P coating had amorphous structure, after heat treatment it changed to crystalline structure with texture for nickel grains. Furthermore, the results showed that functionally graded and step-wise multilayer coatings were deposited successfully by using the same initial bath and changing the temperature and pH during deposition. Nanoindentation test results showed that the hardness of the mentioned coatings changed from 670 Hv near the substrate to 860 Hv near the top surface of coatings. For functionally graded coating the hardness profile had gradual changes, while step-wise multilayer coating had step-wise hardness profile. After heat treatment trend of hardness profiles was changed, so that near the substrate, hardness was measured 1400 Hv and changed to 1090 Hv at the top coat.

  4. Ultrasound assisted dispersal of a copper nanopowder for electroless copper activation.

    Science.gov (United States)

    Graves, John E; Sugden, Mark; Litchfield, Robert E; Hutt, David A; Mason, Timothy J; Cobley, Andrew J

    2016-03-01

    This paper describes the ultrasound assisted dispersal of a low wt./vol.% copper nanopowder mixture and determines the optimum conditions for de-agglomeration. A commercially available powder was added to propan-2-ol and dispersed using a magnetic stirrer, a high frequency 850 kHz ultrasonic cell, a standard 40 kHz bath and a 20 kHz ultrasonic probe. The particle size of the powder was characterized using dynamic light scattering (DLS). Z-Average diameters (mean cluster size based on the intensity of scattered light) and intensity, volume and number size distributions were monitored as a function of time and energy input. Low frequency ultrasound was found to be more effective than high frequency ultrasound at de-agglomerating the powder and dispersion with a 20 kHz ultrasonic probe was found to be very effective at breaking apart large agglomerates containing weakly bound clusters of nanoparticles. In general, the breakage of nanoclusters was found to be a factor of ultrasonic intensity, the higher the intensity the greater the de-agglomeration and typically micron sized clusters were reduced to sub 100 nm particles in less than 30 min using optimum conditions. However, there came a point at which the forces generated by ultrasonic cavitation were either insufficient to overcome the cohesive bonds between smaller aggregates or at very high intensities decoupling between the tip and solution occurred. Absorption spectroscopy indicated a copper core structure with a thin oxide shell and the catalytic performance of this dispersion was demonstrated by drop coating onto substrates and subsequent electroless copper metallization. This relatively inexpensive catalytic suspension has the potential to replace precious metal based colloids used in electronics manufacturing. PMID:26585024

  5. Create Your Plate

    Medline Plus

    Full Text Available ... Student Resources History of Diabetes Resources for School Projects How to Reference Our Site Diabetes Basics Myths ... Close www.diabetes.org > Food and Fitness > Food > Planning Meals > Create Your Plate Share: Print Page Text ...

  6. Plate tectonics: Metamorphic myth

    Science.gov (United States)

    Korenaga, Jun

    2016-01-01

    Clear evidence for subduction-induced metamorphism, and thus the operation of plate tectonics on the ancient Earth has been lacking. Theoretical calculations indicate that we may have been looking for something that cannot exist.

  7. Create Your Plate

    Medline Plus

    Full Text Available ... Food Planning Meals Diabetes Meal Plans and a Healthy Diet Create Your Plate Meal Planning for Vegetarian Diets Gluten Free Diets Holiday Meal Planning Cook with Heart-Healthy Foods donate en -- Diabetes Must Be Stopped - 2016- ...

  8. Create Your Plate

    Medline Plus

    Full Text Available ... Student Resources History of Diabetes Resources for School Projects How to Reference Our Site Diabetes Basics Myths ... simple steps . We want to see your real-life healthy plates! Snap a photo and share it ...

  9. Tectonic Plate Movement.

    Science.gov (United States)

    Landalf, Helen

    1998-01-01

    Presents an activity that employs movement to enable students to understand concepts related to plate tectonics. Argues that movement brings topics to life in a concrete way and helps children retain knowledge. (DDR)

  10. Create Your Plate

    Medline Plus

    Full Text Available ... Healthy Diet Create Your Plate Meal Planning for Vegetarian Diets Gluten Free Diets Holiday Meal Planning Cook ... Blog Online Community Site Menu Are You at Risk? Diagnosis Lower Your Risk Risk Test Alert Day ...

  11. Create Your Plate

    Medline Plus

    Full Text Available ... million battle diabetes and every 23 seconds someone new is diagnosed. Diabetes causes more deaths a year ... Month celebrations , the American Diabetes Association launched this new Create Your Plate interactive tool to help Latinos/ ...

  12. Fractal multifiber microchannel plates

    Science.gov (United States)

    Cook, Lee M.; Feller, W. B.; Kenter, Almus T.; Chappell, Jon H.

    1992-01-01

    The construction and performance of microchannel plates (MCPs) made using fractal tiling mehtods are reviewed. MCPs with 40 mm active areas having near-perfect channel ordering were produced. These plates demonstrated electrical performance characteristics equivalent to conventionally constructed MCPs. These apparently are the first MCPs which have a sufficiently high degree of order to permit single channel addressability. Potential applications for these devices and the prospects for further development are discussed.

  13. Process and Performances of Electroless Ni-P Alloy Coating on Tin Bronze%锡青铜化学镀Ni-P合金工艺及镀层性能

    Institute of Scientific and Technical Information of China (English)

    王敏; 刘锦云; 李文鹏; 陈立甲

    2015-01-01

    ABSTRACT:Objective To improve the wear resistance and corrosion resistance of the tin bronze by Ni-P alloy coating. Methods The tin bronze samples were activated by the acid activation solution with zinc and the plating was performed under the same condi-tion. The properties of these state plated samples underwent heat treatment in the different temperatures (250, 400, 500 ℃) were compared, including the matrix, the plating coating and the coating after heat treatment. The impact was investigated of the diffe-rent heat treatment temperatures on microstructure, microhardness, wear resistance and corrosion resistance of electroless Ni-P al-loy coating on the tin bronze. Results The Ni-P alloy coating was formed on the surface of the tin bronze surface, the state plating coa-ting has no void defect with the base;instead, a good combination was observed;moreover, the deposition is faster, namely, 10. 00 μm/h. The microstructure of the coating transforms from amorphous to crystalline after heat treatment was studied, and the microhardness and wearability of the coating was best after 500 ℃ heat treatment, the corrosion resistance of the state plating coa-ting and the coating after 250 ℃ heat treatment was obviously better than the tin bronze substrate in 10% HNO3 solution and 10%H2SO4 solution, and the corrosion rate of the state plating coating was respectively 0. 225 mg/(cm2·d) and 0. 146 mg/(cm2·d) in the two kinds of medium solutions. Conclusion By the acid activation solution with zinc, electroless Ni-P alloy coating can be successfully prepared on the tin bronze surface with a nice plating effect. Our results show that the technology of electroless Ni-P al-loy on copper can be also applied to the tin bronze.%目的:在锡青铜基体上化学镀Ni-P合金镀层,提高锡青铜的耐磨性和耐腐蚀性。方法以酸性含锌活化液活化锡青铜试样,在相同的条件下实施化学镀,并对镀态试样进行不同温度(250,400,500℃)下的

  14. Development of electroless Ni-P-B4C composite coatings%镍-磷-碳化硼化学复合镀层的研制

    Institute of Scientific and Technical Information of China (English)

    KARTHIKEYAN S; VENKATACHALAM G; SRINIVASAN K N; VASUDEVAN T; NARAYANAN S

    2011-01-01

    Ni-P-B4C composite coatings were prepared on mild steel by electroless plating from a stable bath containing nickel carbonate 15 g/L, hypophosphorous acid 32 mL/L, sodium hypophosphite 15 g/L, lactic acid 32 mL/L, acetic acid 18 g/L, propionic acid 3 mL/L, dimethylamine 1.7 g/L, and boron carbide (B4C) particles 0-25 g/L. The microhardness of the composite coatings was examined by Vickers tester, the wear resistance by Taber abrasion tester, the microscopic morphology and structure by SEM and X-ray diffraction, and the corrosion resistance by potenfiodynamic polarization and electrochemical impedance spectroscopy. The incorporation of B4C increases the microhardness, wear resistance, and corrosion resistance of the Ni-P alloy matrix. The Ni-P-B4C composite coating features a popcorn-like structure with coarse-grained composite particles.%在由碳酸镍15 g/L、次磷酸32 mL/L、次磷酸钠15 g/L、乳酸32mL/L、乙酸189/L、丙酸3mL/L、二甲胺1.7g/L及碳化硼(即B4C)0~25 g/L组成的稳定镀液中,采用化学镀的方法在低碳钢上制备了Ni-P-B4C复合镀层.其显微硬度采用韦氏硬度法测量,耐磨性用Taber磨耗试验机测量,微观形貌和组织采用扫描电镜和X射线衍射进行分析,耐蚀性以动电位极化及电化学阻抗谱测定.碳化硼的掺入提高了镍-磷合金基体的显微硬度、耐磨性和耐蚀性.Ni-P-B4C复合镀层颗粒粗大,具有爆米花式组织结构.

  15. 金刚石表面化学镀铜工艺的优化%Parameters optimization of electroless deposition of Cu on Cr-coated diamond

    Institute of Scientific and Technical Information of China (English)

    A. R. NIAZI; 李树奎; 王迎春; 刘金旭; 呼陟宇; Zahid USMAN

    2014-01-01

    Electroless copper plating on diamond particles precoated with 1%Cr was carried out to evaluate the effects of various experimental parameters on coating quality and deposition rate to obtain the optimized reaction parameters. The formulated samples under optimized parameters were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, X-ray photoelectron spectra and optical microscopy. The best parameters, where uniform and maximum coating thickness was achieved, are etching with 20%NaOH for 30 min, sensitization and activation with SnCl2 and PdCl2 for 5 and 20 min, respectively. The composition of the copper solution bath was 16 g/L CuSO4·5H2O, 35 mL/L formaldehyde (HCHO), 23 g/L KNaC4H4O6 at 60 °C, pH=13 and stirring at (350±15) r/min under ultrasonication.%研究预镀1%铬金刚石颗粒表面化学镀铜的预处理工艺、镀液成分和工艺参数对表面形貌、沉积效率、镀层均匀性等的影响,优化出最佳工艺参数。结果表明,采用20%NaOH溶液处理30 min后,再在SnCl2溶液中进行5 min敏化和在PbCl2溶液中进行20 min活化,能提高预镀1%铬金刚石颗粒表面镀铜质量,并获得较高的铜沉积率。化学镀铜最佳工艺条件为:16 g/L CuSO4·5H2O,35 mL/L甲醛,23 g/L酒石酸钾钠,温度60°C,pH=13,辅助超声加(350±15) r/min的机械搅拌。采用此工艺在预镀1%铬金刚石颗粒表面获得了厚度均匀的纯铜层。

  16. Electroless Co-Zn Surface-modified Nickel Hydroxide as an Active Material for Pasted Nickel Electrodes

    Institute of Scientific and Technical Information of China (English)

    SONG Quan-sheng(宋全生); TANG Zhi-yuan(唐致远); GUO He-tong(郭鹤桐); CHAN S L I

    2004-01-01

    Chemically precipitated β-type nickel hydroxide powder was surface-modified by electroless deposition of Co-Zn coatings,and physical properties of both the modified and unmodified nickel hydroxide were characterized by scanning electron microscopy (SEM), specific surface area (BET), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). It has been found that Co and Zn components of the surface electroless coatings exist in the oxidized state. Electrochemical performances of pasted nickel electrodes using the modified nickel hydroxide as an active material were investigated, and compared with those of the electrodes prepared with the unmodified nickel hydroxide. Charge/discharge tests show that the modified nickel hydroxide electrodes exhibit better performances in the charge efficiency, specific discharge capacity and active material utilization. Their resistance to swelling with cycling is also superior to that of the unmodified nickel hydroxide electrodes. Cyclic voltammetric (CV) studies indicate that the modified electrodes have a higher electrochemical activity, and the porous pasted nickel electrodes have some distinguished CV characteristics in comparison with those of the thin film nickel electrodes.

  17. Electroless Deposition and Nanolithography Can Control the Formation of Materials at the Nano-Scale for Plasmonic Applications

    Directory of Open Access Journals (Sweden)

    Maria Laura Coluccio

    2014-03-01

    Full Text Available The new revolution in materials science is being driven by our ability to manipulate matter at the molecular level to create structures with novel functions and properties. The aim of this paper is to explore new strategies to obtain plasmonic metal nanostructures through the combination of a top down method, that is electron beam lithography, and a bottom up technique, that is the chemical electroless deposition. This technique allows a tight control over the shape and size of bi- and three-dimensional metal patterns at the nano scale. The resulting nanostructures can be used as constituents of Surface Enhanced Raman Spectroscopy (SERS substrates, where the electromagnetic field is strongly amplified. Our results indicate that, in electroless growth, high quality metal nanostructures with sizes below 50 nm may be easily obtained. These findings were explained within the framework of a diffusion limited aggregation (DLA model, that is a simulation model that makes it possible to decipher, at an atomic level, the rules governing the evolution of the growth front; moreover, we give a description of the physical mechanisms of growth at a basic level. In the discussion, we show how these findings can be utilized to fabricate dimers of silver nanospheres where the size and shape of those spheres is controlled with extreme precision and can be used for very large area SERS substrates and nano-optics, for single molecule detection.

  18. Electroless deposition and nanolithography can control the formation of materials at the nano-scale for plasmonic applications.

    Science.gov (United States)

    Coluccio, Maria Laura; Gentile, Francesco; Francardi, Marco; Perozziello, Gerardo; Malara, Natalia; Candeloro, Patrizio; Di Fabrizio, Enzo

    2014-01-01

    The new revolution in materials science is being driven by our ability to manipulate matter at the molecular level to create structures with novel functions and properties. The aim of this paper is to explore new strategies to obtain plasmonic metal nanostructures through the combination of a top down method, that is electron beam lithography, and a bottom up technique, that is the chemical electroless deposition. This technique allows a tight control over the shape and size of bi- and three-dimensional metal patterns at the nano scale. The resulting nanostructures can be used as constituents of Surface Enhanced Raman Spectroscopy (SERS) substrates, where the electromagnetic field is strongly amplified. Our results indicate that, in electroless growth, high quality metal nanostructures with sizes below 50 nm may be easily obtained. These findings were explained within the framework of a diffusion limited aggregation (DLA) model, that is a simulation model that makes it possible to decipher, at an atomic level, the rules governing the evolution of the growth front; moreover, we give a description of the physical mechanisms of growth at a basic level. In the discussion, we show how these findings can be utilized to fabricate dimers of silver nanospheres where the size and shape of those spheres is controlled with extreme precision and can be used for very large area SERS substrates and nano-optics, for single molecule detection. PMID:24681672

  19. Corrosion resistance enhancement of Ni-P electroless coatings by incorporation of nano-SiO2 particles

    International Nuclear Information System (INIS)

    Composite coatings were prepared using hypophosphite reduced electroless nickel bath containing 7 g/L SiO2 nano-particles at pH 4.6 ± 0.2 and temperature 90 ± 2 oC. Deposition rate for SiO2 nano-composite coatings was 10-12 μm/h. The amount of SiO2 nano-particles co-deposited in the Ni-P matrix was around 2 wt.%. The analyzes of coating compositions, carried out by Energy Dispersive Analysis of X-ray (EDAX), showed that plain Ni-P and Ni-P/nano-SiO2 deposits contained around 8 wt.% phosphorus. The X-ray diffraction (XRD) pattern of Ni-P/nano-SiO2 coating was very similar to that of plain electroless Ni-P coating, whose structure was also amorphous. Scanning electron microscopy (SEM) morphology of the surface deposits revealed that some agglomeration occurred because of the absence of surfactant. Electrochemical impedance spectroscopy and polarization tests showed that addition of nano-SiO2 particles demonstrated significant improvement of corrosion resistance of Ni-P coatings in salty atmosphere.

  20. Effect of reducing agent and nano Al2O3 particles on the properties of electroless Ni–P coating

    International Nuclear Information System (INIS)

    This work is an experimental study on the formation, characteristics and properties of electroless nickel phosphorous (Ni–P) coatings and electroless nickel alumina (Ni–P–Al2O3) coating with varying reducing agent concentration. The results obtained indicate that the deposition rate and surface roughness of both Ni–P coating and Ni–P–Al2O3 coatings are highly influenced by reducing agent (sodium hypophosphite). With increase in sodium hypophosphite Ni forms amorphous phase and as a result the micro hardness of the coating gets reduced. Heat treatment was carried out at 400 °C for 1 h after the coating, resulted in the formation of an intermetallic nickel phosphide (Ni3P) phase which improved the hardness of the Ni–P coating from 400 ± 25 to 700 ± 25 HV. A composite coating is formed due to the incorporation of nano alumina in the Ni–P coating leading to an increase in the hardness. The chemical composition of nickel gets reduced from 85.3 to 77.8 wt.% due to the presence of alumina which resists the deposition of Ni. The uniform distribution of alumina particles are observed using a scanning electron micrograph and confirmed by X-ray diffraction techniques. The specific wear rate of Ni–P–Al2O3 coated and post coating heat treated specimens was observed to be less when compared with that obtained in the case of conventional Ni–P coating.