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Steel Substrate (steel + substrate)
Kinds of Steel Substrate Selected AbstractsMicrostructure Characterization of Tool Steel Claddings Co-Extruded on Low Alloyed Steel Substrates,ADVANCED ENGINEERING MATERIALS, Issue 5 2009Pedro Augusto da Souza e Silva Low-alloyed steel bars are hot extruded with pre-sintered tool-steel powders with or without the addition of tungsten carbides (W2C/WC) as hard particles. An extrudate is formed consisting of a wear resistant coating layer and a bulk steel bar as the substrate core. The microstructure at the interface between coating and substrate of different coatings is characterized using OM, SEM and EBSD. [source] Synthesis of Al2O3,SiO2 Films by Ar/O2 Plasma-Enhanced CVD from Alkoxide Precursors,CHEMICAL VAPOR DEPOSITION, Issue 5 2006Y. Li Amorphous Al2O3, SiO2, and Al2O3,SiO2 composite films have been produced at 800,°C from alkoxide solution precursors by liquid-injection oxygen plasma enhanced CVD. The films' structures and morphologies are affected by the feed rate of the liquid precursor and their compositions can be controlled by adjusting the Si/Al ratios in the starting source. Steel substrates coated with the above films gained excellent protection when they were exposed to high temperature atmosphere containing KCl vapor. [source] High Velocity Oxy Fuel Spraying of Cold Work Tool Steels- A Novel Approach to Thick Coatings for Wear Protection Applications,ADVANCED ENGINEERING MATERIALS, Issue 12 2009Arne Röttger Abstract Within this work, HVOF sprayed coatings based on X220CrVMo13-4 cold work steel were applied to a S235JR construction steel substrate. The investigations focus on the influence of particle size and spray parameters on the coating microstructure, analyzed by means of optical microscope (OM) and scanning electron microscopy (SEM). Additional XRD measurements and micro hardness plots across the interface between substrate material and coating were carried out. Furthermore, the influence of particle size on the detected phases and coating porosity was studied. The results were compared with an X220CrMoV13-4 reference sample produced by HIP. [source] On the peel behavior of polymer coating,steel system: Effect of hygrothermal agingADVANCES IN POLYMER TECHNOLOGY, Issue 3 2010N. Guermazi Abstract This paper describes the development and application of a new peel protocols for the evaluation of adhesion of a flexible-to-rigid assembly. The developed apparatus allows simulating and predicting the delamination of the polymer coating from the steel substrate. The effect of certain test parameters such as a peel angle and peel speed was discussed. The durability of the retained assembly was equally investigated by considering an accelerated hygrothermal aging. The interfacial damages after conditioning and peel tests were characterized. Using two peeling angles of 90° and 180°, no significant difference was observed in terms of peel responses. The interface behavior seems to be not sensitive to the peel angle. However, an increase in the peel rate induces an increase in the peel strength. The characterization of the interface exhibits two mechanisms: The delamination process of the polymer coating is characterized by cohesive and mixed rupture, respectively, at low and high peel rates. Studying the effects of aging and coating defects on the interface behavior displays a continuous loss of adhesion of the polymer coating especially when it presents physical defects. © 2010 Wiley Periodicals, Inc. Adv Polym Techn 29:185,196, 2010; View this article online at wileyonlinelibrary. DOI 10.1002/adv.20188 [source] Adhesion of Staphylococcus aureus and Staphylococcus epidermidis to the Episkin® reconstructed epidermis model and to an inert 304 stainless steel substrateJOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2004G. Lerebour Abstract Aims:, The aim of this study was to evaluate the respective influence of the physicochemical interactions and the roughness involved in the first part of the biological substrate biocontamination. Methods and Results:, Therefore we compared the bioadhesion results obtained on the biological model substrate (Episkin®) and on a commonly employed inert substrate (AISI 304 stainless steel), frequently used either in dermatology or in development of medical devices. The two studied strains presented different characteristics, both physicochemical and microbiological. Staphylococcus epidermidis, a relatively hydrophobic bacteria capable of exchanging interactions which are principally of the van der Waals type, adhered more to 304 steel than to the surface of reconstituted skin. As for S. aureus, an essentially basic, hydrophilic bacteria, was more adherent to Episkin® (a bipolar, hydrophilic substrate) than to stainless steel (a unipolar, basic, hydrophilic substrate). Conclusions:, In the absence of electrostatic interactions, the adhesion of substrate-dependent bacteria to the surface of reconstituted skin was dependent upon the balance between ,LW, ,+ and ,,. Significance and Impact of the Study:, Consequently, so as to restrict microbial adhesion and reduce adhesive binding between micro-organisms and the surface of the skin, it would be preferable to render this substrate hydrophobic and apolar through the use of appropriate surface treatment. [source] Supercapacitor studies of electrochemically deposited PEDOT on stainless steel substrateJOURNAL OF APPLIED POLYMER SCIENCE, Issue 2 2007S. Patra Abstract There has been increasing interest on various properties and applications of electronically conducting polymers. Polyethylenedioxythiophene (PEDOT) is an interesting polymer of this type as it exhibits very high ionic conductivity. In the present study, PEDOT has been electrochemically deposited on stainless steel (SS) substrate for supercapacitor studies. PEDOT/SS electrodes prepared in 0.1M H2SO4 in presence of a surfactant, sodium dodecylsulphate (SDS), have been found to yield higher specific capacitance (SC) than the electrodes prepared from neutral aqueous electrolyte. The effects of concentration of H2SO4, concentration of SDS, potential of deposition, and nature of supporting electrolytes used for capacitor studies on SC of the PEDOT/SS electrodes have been studied. SC values as high as 250 F/g in 1M oxalic acid have been obtained during the initial stages of cycling. However, there is a rapid decrease in SC on repeated charge-discharge cycling. Spectroscopic data reflect structural changes in PEDOT on extended cycling. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 [source] Effect of contact configuration on the durability and friction coefficient of pressure-sprayed MoS2 coatings under fretting conditions,LUBRICATION SCIENCE, Issue 5 2009D. B. Luo Abstract Fretting wear is often found at the contact surfaces of a tight assembly where small-amplitude oscillatory movement occurs, which can be the concealed origin of some enormous accidents. Employment of solid lubrication coatings, as one of effective measurements to palliate the fretting damage, has been widely acknowledged. The present work studied the fretting behaviour of a molybdenum disulphide coating on SUS 316 stainless steel substrate by a relatively cheap and easy-to-use process: pressure spraying. Two contact configurations (cylinder-on-flat and ball-on-flat) were used in the tests with different displacement amplitudes (from 5 to 75,µm) and normal loads (from 100 to 400,N for ball-on-flat and from 400 to 1000,N for cylinder-on-flat). The results showed that large displacement amplitude is adverse to friction coefficient and coating lifetime and that under a critical contact pressure, coating endurance is improved contact pressure increases. Contact configuration influences friction coefficient by changing contact area and distribution of contact pressure. One master curve of average dissipated energy per cycle in initial stable stage was obtained for two contact configurations, which can be employed to approximately predict coating lifetime. Copyright © 2009 John Wiley & Sons, Ltd. [source] Corrosion behaviour of aircraft coating systems in acetate- and formate-based de-icing chemicalsMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 3 2009E. Huttunen-Saarivirta Abstract Corrosion behaviour of four coating systems, which are commonly used in aircraft components; namely cadmium-coated and subsequently chromate-treated steel AISI 4340, aluminium-coated steel AISI 4340, anodised aluminium alloy 7075-T6 and chromate-treated aluminium alloy 7075-T6, were investigated in six commercial acetate- and formate-based de-icing chemicals. The results show that the aluminium-coated steel specimens experience least corrosion among the four coating systems; no corrosion is detected in potassium acetate-based de-icing chemicals (Safeway KA HOT, Safegrip and Safegrip+), although some corrosion is observed in the other three chemicals (Safeway SD, Safeway SF and Meltium). In contrast, the coatings in the other three coating systems are damaged in all six de-icing chemicals. The thickness of the coating does not necessarily predict how well the coating will protect the substrate; the thickest coating, several tens of micrometres, is apparent on the cadmium- and chromate-coated steel specimens, while only a few micrometres thin aluminium coating on the steel substrate is the only coating system that can survive the corrosion tests in some of the de-icing chemicals. Comparison of the results from the two test methods used in this research, polarisation measurements and chemical exposure tests, shows that, for each coating system, the extent of corrosion, as evaluated on the basis of weight changes calculated from corrosion current density values and those experienced during chemical exposure tests, is different: the weight changes that materialise during exposure tests are, at least, from one to two orders of magnitude higher than those predicted by calculations. In this paper, these observations are discussed and explanations for them are presented. [source] On-line corrosion and corrosion-wear monitoring using a modified electrochemical noise techniqueMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 6 2005P.-Q. Wu Abstract In this study, a modified electrochemical noise (EN) technique was used to monitor uniform corrosion and pitting corrosion. In the EN technique, one working electrode is coupled to a microelectrode (e.g. Pt) through a zero resistance ammeter to sense current noise. Results show that the EN technique with a properly selected microelectrode appears to be able to distinguish different corrosion processes like uniform corrosion on mild carbon steel and pitting corrosion on stainless steel. Furthermore, this EN technique was successfully implemented in on-line corrosion-wear monitoring of stainless steel. In addition, the modified EN technique can sensitively detect the interface of nitrogen ion implanted layer and the stainless steel substrate, thus determining the thickness of the implanted layer. [source] Laser composite surfacing of stainless steel with SiCPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 9 2006J. Dutta Majumdar Abstract In the present study, an attempt has been made to improve wear resistance of AISI 304 stainless steel by laser composite surfacing with SiC. Laser processing has been carried out by pre-deposition of Fe + SiC powders (in the ratio of 85:15 and thickness of 100 ,m) on AISI 304 stainless steel substrate and subsequently, melting it using a 2 kW continuous wave CO2 laser. Following laser processing, a detailed characterization and evaluation of mechanical/electrochemical properties of the composite layer were undertaken to study the influence of laser processing on the characteristics and properties of the composite layer. Microstructure of the composite layer consisted of uniformly dispersed SiC particles in grain refined ,-Fe dendrites. Laser composite surfacing led to a significant improvement in microhardness and wear resistance as compared to as-received substrate. However, pitting corrosion property was marginally deteriorated due to laser composite surfacing. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Dielectric properties of Li doped Li-Nb-O thin filmsPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 3 2007G. Perentzis Abstract Lithium niobate LiNbO3 was prepared as a thin film layered structure deposited on stainless steel substrate using e-gun evaporation. The Li doping was provided for by the formation of Li-Nb-O/Li/LiNb-O sandwich structure and annealing at about 250 °C. AC impedance spectroscopy measurements were performed on the samples at temperatures from the interval between 28 and 165 °C and in a frequency range of 10,3 to 106 Hz. Using the values Z , and Z , at different frequencies, the dielectric parameters , parts of the complex permittivity ,, and ,, and loss tangent tan , were calculated. The results prove validity of the proposed equivalent circuit containing parallel RC elements connected in series where the first RC element represents the bulk of material and the second RC element belongs to the double layer at the metal interface. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Mechanical and Tribological Properties of Cr-DLC Coatings Deposited by ARC-MAG-RF PACVD Hybrid MethodPLASMA PROCESSES AND POLYMERS, Issue S1 2007Andrzej Czyzniewski Abstract The procedure of Cr-DLC coating deposition using a hybrid ARC-MAG-RF PACVD method is presented in this paper. ARC and MAG techniques were used to deposit a Cr/Cr-C:H interlayer with increasing hardness, but a nearly constant elastic modulus of the value similar to a steel substrate and DLC layer deposited then by RF PACVD technique. As a result of such coating formation the lower level of stresses in the coating-substrate system, both intrinsic and induced by the load applied, was obtained. The resultant Cr-DLC coating is marked by high crack resistance and high adhesion. The Cr-DLC coating shows high wear resistance, but the wear geometry and the friction coefficient depend on a type of the counterpart material. [source] Role of the support material on laser desorption/ionization mass spectraRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 7 2008A. Gruszecka We report the results of experimental studies on the effects of sample supports in laser desorption/ionization mass spectrometry (LDI-MS). LDI time-of-flight (TOF) mass spectra obtained for C60 and insulin samples deposited onto standard stainless steel substrate and/or onto some non-metallic materials (glass, scotch tape, floppy disc foil, Teflon foil, photocopy film), all recorded under identical, typical experimental conditions, have been compared with regard to their intensity and quality. The LDI investigations show that compared with stainless steel, glass and floppy disc foil sample supports boost (2,3.5 times) ion yields for C and C ions, respectively. The stainless steel and scotch tape sample supports are the best for the mass resolution of positive ions and the formation of (C60) (n,,,4) cluster ions, respectively. In the case of detection of insulin by matrix-assisted laser desorption/ionization (MALDI) we did not observe significant differences in sensitivity for the support materials tested. A mechanism of ion formation in the desorption plume is suggested. Copyright © 2008 John Wiley & Sons, Ltd. [source] Characterization of reactive DC magnetron sputtered TiAlN thin filmsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 10 2008B. Subramanian Abstract Thin films of about 1,m Titanium Aluminum Nitride (TiAlN) were deposited onto mild steel substrates by reactive direct current (DC) magnetron sputtering using a target consisting of equal segments of titanium and aluminum. X-ray diffraction (XRD) analysis showed that the TiAlN phase had preferred orientations along 111 and 200 with the face-centered cubic structure. Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM) analyses indicated that the films were uniform and compact. Photoluminescence (PL) spectra reveal that TiAlN thin films are of good optical quality. Laser Raman studies revealed the presence of characteristic peaks of TiAlN at 312.5, 675, and 1187.5 cm,1. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Rapid determination of stress factors and absolute residual stresses in thin filmsJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 6 2006E. Eiper A methodology is presented that allows the determination of experimental stress factors in thin films on the basis of static diffraction measurements. The approach relies on the characterization of thin films deposited on a monocrystalline substrate serving as a mechanical sensor. Rocking-curve measurements of the symmetrical reflections of the substrate are used to determine the substrate curvature and subsequently the macroscopic stress imposed on the film. The elastic strain in the film is determined by lattice-spacing measurement at different sample tilt angles. The calculated experimental stress factors are applied to thin films deposited on other types of substrates and are used to determine the absolute magnitude of the residual stress. The approach is applied to nanocrystalline TiN and CrN thin films deposited on Si(100) and steel substrates, characterized using a laboratory-type ,/, goniometer. [source] Novel repair method for technical enamels based on sol,gel and sol-dispersion coatings,MATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 2 2008S. Benfer The aim of the work presented here is the development of a novel repair method for technical enamels by using chemical nanotechnology. Good adhesion of coatings requires good wettability of the substrate by the repair solution. This was achieved by different pre-treatments of the steel substrates. Low sintering temperatures of the coatings can be ensured by the use of nanoparticle-based systems. Based on liquid metal alkoxides, a colloidal alumina sol and metal salts homogeneous sols with up to seven enamel compounds were prepared. The sols were brush coated onto plain and partly enamelled steel substrates and sintered in a furnace, by inductive heating or an IR emitter. Thin (single layer,,,1µm) crack-free layers were obtained on nearly all substrates independent of the sintering conditions investigated. The local sintering methods (IR emitter, inductive heating) allow to produce multiple coating systems in short times. Electrochemical impedance spectroscopy (EIS) provides evidence of the protective effect of these layers compared to the bare substrate, but as a result of their chemical composition the layers are not stable in the electrolytic environment for longer times. The thickness of such multiple coatings (20 layers, ,,8 µm) is still small compared to that of a technical enamel. Therefore, sol dispersion systems containing powder particles and sol components are applied on top of the sol,gel layers to increase the thickness of the sintered layers. [source] Interdiffusional degradation of oxidation-resistant aluminide coatings on Fe-base alloysMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 10 2007Y. Zhang One of the potential degradation modes of oxidation-resistant iron aluminide coatings is the loss of Al from the coatings into Fe-base substrate alloys that typically contain no Al. To address this issue, interdiffusion between aluminide coatings and steel substrates was studied for times up to 10,000 h in the temperature range of 500,800,°C. Coatings were synthesized in a laboratory chemical vapor deposition (CVD) reactor on representative commercial ferritic alloy Fe-9Cr-1Mo and type 304L austenitic stainless steel. The microstructural and compositional changes after diffusion anneals were examined in detail. An initial attempt to model the interdiffusion behavior was carried out by applying an existing software program COSIM (coating oxidation and substrate interdiffusion model). Complementary work was conducted using a simple mathematic model developed by Heckel et al. Reasonable agreement was observed between the simulated and experimental composition profiles for the aluminide coatings on ferritic alloys. Model results were then applied to predict coating lifetime. [source] Mechanical and tribological characterization of CNx films deposited by d.c. magnetron sputteringPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 11 2007L. Ipaz Abstract Carbon nitride (CNx) thin films were deposited onto silicon and steel substrates at 400 °C from a carbon target by d.c. magnetron sputtering system. The composition, structural, and mechanical properties of deposited films were investigated as a function of argon/nitrogen concentration and sputtering power, by means of Energy Dispersive X-ray Spectroscopy (EDS), Fourier Transform Infrared Spectroscopy (FTIR), Raman Spectroscopy (RS), and nanoindentation. The EDS and Elastic Forward Analisys Analysis (EFA) showed that the nitrogen concentration in the CNx deposited films varied between 16% and 28% at depending on nitrogen concentrations in argon/nitrogen gas mixture, and deposition power. FTIR analysis indicated the presence of 2266 and 2278 cm,1 stretching peaks associated with CN triple bonds of nitriles and isocyanides, 1640 cm,1 and 1545 cm,1 associated with the C=C and C=N bonds. The thickness of the CNx deposited films varied between 0.4 and 0.8 µm at different sputtering powers. The hardness and Young's modulus were investigated by depth sensing nanoindentation method. The obtained hardness and Young's modulus increased from 4 to 17 GPa, and from 50 to 170 GPa, respectively; when the nitrogen content in the deposited films diminished between 28 and 12%. On the other hand, the friction and wear tests were done using a pin-on-disc tribometer. The friction tests showed values of 0.05 and 0.4 in dry air and humid atmosphere; respectively. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Gas Phase Modification of Superhard Carbon Coatings Deposited by Pulsed DC-Arc-ProcessPLASMA PROCESSES AND POLYMERS, Issue S1 2009Werner Grimm Abstract The pulsed vacuum arc discharge (pulsed arc) is the most efficient PVD technology for deposition of hard amorphous carbon coatings on tools and machinery parts. Due to the pulsed arc discharge a stable evaporation process and the efficient deposition of hydrogen-free a-C type coatings is possible. This paper shows that the pulsed arc enables the deposition of ta-C and modified a-C coatings with interesting coating properties in a wide pressure range of argon, acetylene and ammonia gas atmosphere. Coatings with different gas flow rates of these gases were deposited on steel substrates. The coating properties were characterized by using different analytical methods for determination of structure, hardness, friction and wear behaviour. The changes of film properties in dependence of the kind and the rate of gas flow are compared and discussed. [source] | |||||||||||||||||||||||||