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Electronics, Electronique, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Méthodes de nanofabrication, Methods of nanofabrication, Formation de nanomotifs, Nanoscale pattern formation, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Electronique, Electronics, Electronique des semiconducteurs. Microélectronique. Optoélectronique. Dispositifs à l'état solide, Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices, Dispositifs à ondes acoustiques, piézoélectriques, piézorésistifs, Acoustic wave devices, piezoelectric and piezoresistive devices, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Composé III-VI, III-VI compound, Compuesto III-VI, Alumine, Alumina, Alúmina, Tonerde, Aluminium, Aluminio, Angle contact, Contact angle, Angulo contacto, Kontaktwinkel, Anodisation, Anodizing, Anodización, Elektrolytisches Oxidieren, Courant intense, High strength current, Corriente intensa, Diminution coût, Cost lowering, Reducción costes, Kostensenkung, Dispositif entraînement, Driving device, Dispositivo arrastre, Durcissement, Hardening, Endurecimiento, Haerten, Electrolyte acide, Acid electrolyte, Electrólito ácido, Evaluation performance, Performance evaluation, Evaluación prestación, Formation nanomotif, Nanopatterning, Formacíon nanomotivo, Gyroscope, Giroscopio, Microscopie électronique balayage, Scanning electron microscopy, Microscopía electrónica barrido, Rasterelektronenmikroskopie, Nanocomposite, Nanocompuesto, Nanofil, Nanowires, Nanostructure, Nanoestructura, Précision élevée, High precision, Precisión elevada, Rotor, Surface rugueuse, Rough surface, Superficie rugosa, Rauhe Oberflaeche, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Traitement(durcissement), Curing, Vitesse déplacement, Speed, Velocidad desplazamiento, Geschwindigkeit, 0707D, 8107B, 8107V, 8116R, Al2O3, Matériau nanostructuré, Nanostructured material, Drag reduction, Liquid-floated rotor gyroscope, Nanostructured, and Oleophobic

Liquid-floated rotor gyroscopes can provide high accuracy at small volume and low cost. In rotor gyroscopes, the rotating speed of rotor can significantly affect the detection accuracy. This work presents a new kind of liquid-floated rotor gyroscope using super-oleophobic surface processing, which can improve the performance of driving system. In this work, an unconventional anodization in oxalic-acid electrolyte under high current was employed to fabricate diverse nanostructured alumina surfaces. The top-view SEM image shows the nanowire pyramid structure on the surface of processed sample. Modification of the rough surfaces was achieved by dipping substrates in 0.5 wt% 1H,1H,2H,2H-perfluoro-octadecyltrichlorosilane-in-hexane and then curing then at 120 °C for 1 h. The maximum contact angle (CA) of the aluminum rotor with nanowire pyramid structure was measured to be 156° in average. The oleophobicity of the rotor surface was used to reduce the resistance in the floating liquid. The test results show that, under the normal working state, the rotating speed of super-oleophobic rotor can be reached up to 3200 rpm. While a similar system without the micro-nano composite structure can only reach 2860 rpm. Thus, the nanostructured super-oleophobic alumina surface processing can greatly increase the rotating speed, thereby improving the performance of the gyro system.

Electronics, Electronique, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Propriétés et matériaux diélectriques, piézoélectriques et ferroélectriques, Dielectrics, piezoelectrics, and ferroelectrics and their properties, Propriétés diélectriques des solides et des liquides, Dielectric properties of solids and liquids, Permittivité (fonction diélectrique), Permittivity (dielectric function), Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Nanomatériaux et nanostructures : fabrication et caractèrisation, Nanoscale materials and structures: fabrication and characterization, Fils quantiques, Quantum wires, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Acrylique acide polymère, Acrylic acid polymer, Acrílico ácido polímero, Attaque chimique, Chemical etching, Ataque químico, Chemisches Aetzen, Caractéristique électrique, Electrical characteristic, Característica eléctrica, Elektrische Groesse, Centre accepteur, Acceptor center, Centro aceptor, Conduction limitée charge espace, Space-charge-limited conduction, Conductivité électrique, Electrical conductivity, Constante diélectrique, Permittivity, Coprécipitation, Coprecipitation, Dépôt par oxydoréduction, Electroless deposition, Eau, Water, Hydrophilie, Hydrophily, Hidrofilia, Loi Ohm, Ohm law, Matériau composite, Composite materials, Nanofil, Nanowires, Nanoparticule, Nanoparticles, Oxyde de titane, Titanium oxide, Titanio óxido, Titanoxid, Passivation, Phénomène transport, Transport processes, Piège, Traps, Propriété diélectrique, Dielectric properties, Propriété transport, Transport properties, Propiedad transporte, Propriété électrique, Electrical properties, Réseau(arrangement), Arrays, Semiconducteur type n, n type semiconductor, Semiconducteur type p, p type semiconductor, Silicium, Silicon, Tension polarisation, Bias voltage, Voltage polarización, Traitement surface, Surface treatments, 8107V, TiO2, Composite devices, Silicon nanowires, and Space charge limited current

We have presented the composite device including silicon nanowires (SiNWs), Polyacrylic acid (PAA) and Titanium dioxide nanoparticles (TiO2 NPs). SiNWs and TiO2 NPs were synthesized by metal assisted electroless chemical etching (MACE) and co-precipitation method respectively. Solution containing PAA and TiO2 NPs in DI water was spun on already grown vertical SiNW arrays. We have investigated the transport and dielectric properties of p-type SiNWs/PAA/TiO2 NPs (p-SPT) and n-type SiNWs/PAA/TiO2 NPs (n-SPT) composite devices. Presence of PAA/TiO2 NPs on the surface of SiNWs have increased electrical current in p-SPT device than that of n-SPT device. Ohmic like conduction was dominant at lower bias voltages followed by space charge limited current (SCLC) with traps at intermediate voltages. The calculated values of trap densities (Ht) were 7.73 × 1011 cm-3 and 5.34 × 1011 cm-3 for p-SPT device and n-SPT device respectively. Similarly p-SPT device shows higher real part of dielectric constant (ε') and AC conductivity (σac) ~15 times and ∼85 times respectively than that of n-SPT device. Increment in electrical and dielectric properties can be attributed to the presence of hydrophilic materials (PAA/TiO2 NPs) which may results in enhancement of acceptor like states.

Electronics, Electronique, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure, proprietes mecaniques et thermiques, Condensed matter: structure, mechanical and thermal properties, Surfaces et interfaces; couches minces et trichites (structure et propriétés non électroniques), Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties), Interfaces solide-fluide, Solid-fluid interfaces, Mouillage, Wetting, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Electronique, Electronics, Electronique des semiconducteurs. Microélectronique. Optoélectronique. Dispositifs à l'état solide, Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices, Fabrication microélectronique (technologie des matériaux et des surfaces), Microelectronic fabrication (materials and surfaces technology), Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Mécanique fluide, Fluid mechanics, Mecánica flúido, Hydromechanik, Circuit intégré, Integrated circuit, Circuito integrado, Integrierte Schaltung, Dépôt plasma, Plasma deposition, Depósito plasma, Empilement, Stacking, Apilamiento, Encrassement, Fouling, Enmugrecimiento, Epaisseur, Thickness, Espesor, Dicke, Etherethercétone polymère, Polyetheretherketone, Eter éter cetona polímero, Fabrication microélectronique, Microelectronic fabrication, Fabricación microeléctrica, Formation motif, Patterning, Formacíon motivo, Gravure plasma, Plasma etching, Grabado plasma, Haute résolution, High resolution, Alta resolucion, Hydrocarbure fluoré, Fluorocarbon, Hidrocarburo fluorado, Hydrophilie, Hydrophily, Hidrofilia, Hydrophobicité, Hydrophobicity, Hidrofobicidad, Lithographie, Lithography, Litografía, Microfluidique, Microfluidics, Microfluidic, Mode empilement, Stacking sequence, Modo apilamiento, Mouillage, Wetting, Remojo, Méthacrylate de méthyle polymère, Methyl methacrylate polymer, Metacrilato de metilo polímero, Oxygène, Oxygen, Oxígeno, Sauerstoff, Photolithographie, Photolithography, Fotolitografía, Photorésist, Photoresist, Fotorresistencia, Propriété surface, Surface properties, Propiedad superficie, Oberflaecheneigenschaft, Réseau (arrangement), Array, Red, Résist, Resist, Resistencia, Silicium, Silicon, Silicio, Système sur puce, System on a chip, Sistema sobre pastilla, Technologie planaire, Planar technology, Tecnología planar, Traitement par plasma, Plasma assisted processing, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, 4785N, 8116N, 8116R, 8540H, Cancer cell patterning, Fibrosarcoma cancer cell line HT1080, Plasma nanotexturing, Selective cell attachment, cell repelling, Superhydrophobic, antifouling surfaces, and Thick resist patterning

We propose a planar technology for fabrication and surface modification of disposable, polymeric, microfluidic devices, and show applications in cell patterning. By planar technology we mean lithography directly on a polymeric plate followed by plasma etching of the plate. In this context, we developed lithographic processes directly on the polymeric substrate, employing easily strippable photoresists, for which stripping is performed without attacking the polymeric substrate. We then applied oxygen plasma etching to transfer the pattern and chemically modify the polymeric substrates, followed by optional fluorocarbon plasma deposition through stencil masks, producing microfluidic channels with desired geometrical and wetting characteristics. We tested various organic photoresists such as AZ 15nXT, AZ 9260, maP-1275, a silicon containing resist Ormocomp® on an organic strippable underlayer (LOR@), as well as metal masks in order achieve high resolution (1-4 μm), plasma etch resistance, and stripability for photoresists with thickness of ~5-20 μm (for details see Supporting information). We selected the Ormocomp® stack as the best candidate to define microfluidics with plasma etching onto PMMA, PEEK and COP substrates containing hydrophilic and superhydrophobic areas. We demonstrate significantly increased cell attachment on the plasma treated PMMA areas compared to untreated ones, and highly selective cell attachment (on-off) onto hydrophilic versus the superhydrophobic areas using a particular cell line. Such control of cell attachment and growth on plasma nanotextured surfaces can be applied to creation of microdevices aiming to cell patterning, cell isolation, as well as cell arrays.

Electronics, Electronique, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Electrotechnique. Electroenergetique, Electrical engineering. Electrical power engineering, Matériaux, Materials, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Propriétés mécaniques. Rhéologie. Mécanique de la rupture. Tribologie, Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology, Rupture, Fractures, Champ température, Temperature distribution, Contamination chimique, Chemical contamination, Contaminación química, Contrainte thermique, Thermal stresses, Couche autoassemblée, Self-assembled layers, Cycle thermique, Thermal cycle, Ciclo térmico, Temperaturverlauf, Dégradation, Degradation, Délaminage, Delamination, Endommagement, Damage, Etude comparative, Comparative study, Estudio comparativo, Vergleich, Fabrication microélectronique, Microelectronic fabrication, Fabricación microeléctrica, Formation motif, Patterning, Gonflement, Swelling, Matériau composite, Composite materials, Métallisation, Metallizing, Procédé voie sèche, Dry process, Procedimiento vía seca, Propriété surface, Surface properties, Répartition spatiale, Spatial distribution, Répétabilité, Repeatability, Repetibilidad, Siloxane(diméthyl) polymère, Dimethylsiloxane polymer, Siloxano(dimetil) polímero, Température ambiante, Ambient temperature, Traitement surface, Surface treatments, Traitement thermique, Heat treatments, Verre, Glass, 8105K, 8116D, 8116R, 8540H, 8540L, Dry peel-off process, Micro-heaters, Polydimethylsiloxane (PDMS), Self-assembled monolayer (SAM), and Surface modification

The present report describes a reliable fabrication method of micro-heaters embedded in polydimethylsiloxane (PDMS), and shows the characterization of the micro-heaters. Metallization of PDMS is achieved using a dry peel-off process which involves modifying the surface properties of the substrate and metal patterns through self-assembled monolayer (SAM) and manually peeling off the PDMS with embedded metal layers. Thus, micro-heaters embedded in PDMS can be fabricated by a simpler and easier way compared to a conventional method (e.g. patterning a conducting composite of PDMS using a razor blade). As a result, Au micro-heaters embedded in PDMS were successfully fabricated without any chemical swelling and contamination. Micro-heaters on a glass substrate were also fabricated for comparison with those embedded in PDMS. For heating up to 90 °C, the micro-heaters embedded in PDMS needed only ~90 mW compared to those fabricated on the glass substrate needed ~530 mW. Moreover, we could not observe any degradation of the micro-heaters by thermal stresses that confirmed by repeatability (10 thermal cycle with a range of 25-89 °C) and stability test (20 min at 90 °C). Micro-heaters took less than 60 s to reach the target temperature (90 °C) and spent less than 60 s to drop to room temperature. The spatial temperature distribution was not significantly varied with materials of the substrate (i.e. PDMS or glass).

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Ecoulement gaz, Gas flow, Température, Temperature, Traitement surface, Surface treatments, Cold spraying, Initial pressure differential, Powder carrier gas, and Prechamber

In order to inject powder into the nozzle in cold spraying, the pressure of the powder carrier gas at the nozzle inlet must be equal to or higher than the pressure of the propulsion gas, and the temperature of the powder carrier gas needs to be lower than the temperature of the propulsion gas to prevent from buildup or clogging by particles in the nozzle. The gas flow behavior resulting from the lower temperature and the higher pressure of powder carrier gas has an important effect on the particle acceleration in the nozzle. Several issues related to the gas flow will be examined through numerical simulation, including the initial pressure differential, the nozzle throat diameter, and the prechamber length between the injection tube outlet and the nozzle inlet. For different initial pressure differentials, nozzle throat diameters and prechamber lengths, the mixing conditions of the two gas flow streams in the nozzle are quite different and the negative effect of the inadequate mixing of the two gas flow streams in the nozzle on the particle acceleration is obvious. It is found that using lower differential pressure, larger nozzle throat diameter and longer prechamber for a certain diameter of powder injection tube can enhance the particle acceleration in the nozzle.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Méthodes de dépôt de films et de revêtements; croissance de films et épitaxie, Methods of deposition of films and coatings; film growth and epitaxy, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements thermiques, Heat treatment, Traitements thermochimiques et traitements par diffusion, Thermochemical treatment and diffusion treatment, Surface treatment, Acier non allié, Carbon steels, Activité catalytique, Catalyst activity, Actividad catalítica, Couche mince, Thin films, Dépôt physique phase vapeur, Physical vapor deposition, Magnétron, Magnetrons, Nitruration, Nitridation, Oxyde de titane, Titanium oxide, Titanio óxido, Titanoxid, Plasma, Prétraitement, Pretreatment, Pretratamiento, Pulvérisation irradiation, Sputtering, Traitement surface, Surface treatments, Traitement thermochimique, Thermochemical treatment, Tratamiento termoquímico, Thermochemische Behandlung, Carbon steel, Magnetron sputtering, Photocatalysis, Plasma nitriding, and TiO2

This paper presents a comparative study of TiO2 films deposited on plasma nitrided and non-nitrided carbon steel substrates. It is well known that plasma nitriding contributes to increase film adhesion and corrosion resistance of the substrate. However, most studies about photocatalytic properties of TiO2 on steel substrates do not address the use of nitrided carbon steel. The main goal of this paper is to investigate the deposition of photocatalytic TiO2 film on nitrided carbon steel, obtained through a duplex treatment of plasma nitriding and reactive plasma sputtering deposition. TiO2 films were deposited on nitrided and non-nitrided AISI 1015 steel samples. The samples were characterized by X-ray diffraction (XRD), profilometry, scanning electron microscopy (SEM) and atomic force microscopy (AFM). The photocatalytic activity was evaluated by monitoring the effect of photoinduced hydrophilicity and through the degradation of methylene blue dye (MB). The pretreatment by plasma nitriding increases the substrate surface roughness and improves the growth of rutile phase. The roughness of the substrate surface affects wettability only when the TiO2 film is not photoactivated. All samples become super-hydrophilic upon UV irradiation and remaining in this state for at least 24 h. A slightly higher performance in photocatalysis of MB is obtained by TiO2 film deposited on non-nitrided substrate.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Borure de titane, Titanium boride, Titanio boruro, Titanborid, Carbure de titane, Titanium carbide, Titanio carburo, Titancarbid, Electrode, Electrodes, Matériau composite, Composite materials, Qualité, Quality, Calidad, Qualitaet, Revêtement composite, Composite coating, Revestimiento compuesto, Traitement surface, Surface treatments, Coating parameters, Coating quality, Copper alloy electrode, and Titanium diboride-titanium carbide

To improve the lifetime of electrodes used for the resistance spot welding of Zn-coated steel sheets, a TiB2―TiC composite coating was fused onto the surface of spot welding electrodes using an electro-spark deposition (ESD) process. Different processing parameters were studied in order to improve the quality of the electrode coating. The microstructure, elemental composition, phase structure, and mechanical properties of the coatings were characterized by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD) and microhardness testing. When TiB2―TiC is deposited onto the electrodes in air, extensive coating defects occur within the bulk TiB2―TiC coating and at the interface with the electrode; however, coating defects are significantly reduced when the TiB2―TiC is deposited in argon. Delamination and oxidation of the TiB2―TiC coating were prevented and the number of cracks diminished. When TiB2―TiC was deposited in air on an electrode pre-coated with Ni, almost all coating defects were eliminated. The TiB2―TiC coated directly onto electrodes in air was found to have the lowest average microhardness of HV50 650, and the average hardness values obtained in argon and with Ni-coated electrodes were about HV50 1050 and HV50 1080, respectively. A heat-affected zone (HAZ) of about 20 μm in depth within the substrate was observed near the interface between the coating and the substrate for all coating conditions.

General chemistry, physical chemistry, Chimie générale, chimie physique, Crystallography, Cristallographie cristallogenèse, Nanotechnologies, nanostructures, nanoobjects, Nanotechnologies, nanostructures, nanoobjets, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure, proprietes mecaniques et thermiques, Condensed matter: structure, mechanical and thermal properties, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Acier non allié, Carbon steels, Adhérence, Adhesion, Dépôt conversion, Conversion coating, Depósito conversión, Fer, Iron, Microscopie force atomique, Atomic force microscopy, Microscopie électronique balayage, Scanning electron microscopy, Métal transition, Transition elements, Traitement surface, Surface treatments, Zirconium, Fe, Zr, AFM, Cathodic disbonding, EIS, FE-SEM, and Zirconium conversion coating

The effect of zirconium-based surface treatment on the cathodic disbonding resistance and adhesion performance of an epoxy coated mild steel substrate was investigated. The obtained data from pull-off, cathodic disbonding test and electrochemical impedance spectroscopy (EIS) indicated that the zirconium conversion layer significantly improved the adhesion strength and cathodic disbonding resistance of the epoxy coating. This may be attributed to formation of some polar zirconium compounds on the surface and increment of surface roughness, that were evident in the results of field emission scanning electron microscopy (FE-SEM) and atomic force microscopy (AFM), respectively.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Corrosion, Action des agents de corrosion, Corrosion environments, Propriétés mécaniques. Rhéologie. Mécanique de la rupture. Tribologie, Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology, Acier non allié, Carbon steels, Application, Aplicación, Anwendung, Chlorure, Chlorides, Corrosion haute température, High temperature corrosion, Corrosión alta temperatura, Hochtemperaturkorrosion, Elimination déchet, Waste disposal, Haute température, High temperature, Alta temperatura, Hochtemperatur, Incinération, Incineration, Incineración, Indentation, Propriété mécanique, Mechanical properties, Température, Temperature, Traitement surface, Surface treatments, Carbon steel, Instrumented indentation technique, and Municipal solid waste incineration

The effect of exposure temperature on the mechanical properties of scales in a carbon steel was investigated in a simulated waste incineration environment consisting of a gas mixture (N2-O2-H2O-HCl) with samples immersed in a salt (K2SO4-Na2SO4-ZnCl2-KCl) in the temperature range of 573 to 773 K. The microstructure, corrosion rate, elastic modulus (E) and hardness (H) of scales were determined by SEM, XRD, descaled weight loss and instrumented indentation technique. The results indicated that both the E and H decreased as a negative exponential function of temperature, thus obtaining a low mechanical and microstructural integrity of scales with high defect density between 673 and 773 K.

General chemistry, physical chemistry, Chimie générale, chimie physique, Crystallography, Cristallographie cristallogenèse, Nanotechnologies, nanostructures, nanoobjects, Nanotechnologies, nanostructures, nanoobjets, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure, proprietes mecaniques et thermiques, Condensed matter: structure, mechanical and thermal properties, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Europium, Lanthanide, Rare earths, Luminescence, Nanoparticule, Nanoparticles, Traitement surface, Surface treatments, Eu, Dibenzoylmethane, Europium fluoride, Phenanthroline, and Surface modification

Reaction between Eu(NO3)3 and NH4F in aqueous media was applied to produce EuF3 doughnut-like aggregates with a diameter of 200-500 nm and thickness of 50-150 nm composed of nanoparticles with a mean diameter of 16 nm. The impregnation, sorption and mechanochemical treatment were used for surface modification of EuF3 doughnut-like particles with 1,10-phenanthroline and sodium dibenzoylmethanate which are sensitizing ligands for Eu3+ luminescence. The data of transmission electron microscopy, elemental analysis, Fourier transform infrared spectroscopy, and luminescence spectroscopy have proved that the organic ligands are coordinated to surface Eu3+ ions, forming surface complexes. The surface modification of the EuF3 nanoparticles with sodium dibenzoylmethanate and 1,10-phenanthroline leads to increase in the luminescence intensity at 612 nm (5D0 → 7F2 transition) in comparison with the luminescence intensity of the unmodified EuF3 nanoparticles. Energy transfer from the ligand to Eu3+ ion in the surface complexes makes a main contribution to this effect.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Carbone, Carbon, Couche superficielle, Surface layers, Diamant synthétique, Synthetic diamond, Diamante sintético, Dépôt chimique phase vapeur, CVD, Géométrie, Geometry, Microstructure, Plasma, Structure diamant, Diamond structure, Estructura diamante, Traitement surface, Surface treatments, Diamond-like carbon, Plasma CVD, and Surface topography

Potential applications of diamond-like carbon (DLC) coatings range from precision tools and biomedical implants to micro mechanical devices and engine components. Where uniform coatings are required on substrates with complex geometries, plasma enhanced chemical vapour deposition (PECVD) is often a preferred deposition method. As a non-line of sight process, the geometry of the substrate is often considered negligible. For this reason analysis of PECVD coatings, such as amorphous carbon, has mostly been concerned with reactor deposition variables, such as bias voltage, pressure and gas ratios. Samples are therefore usually prepared and positioned to minimise the influence of other variables. By depositing nominally similar DLC films on silicon samples positioned horizontally and vertically on the reactor cathode plate it was possible to examine the variations in the coating characteristics and mechanical properties that occur due to the geometry of the substrate being coated. Topographic measurements and analysis of bonding structures revealed significant heterogeneity in the coatings. Electron microscopy showed variation in surface structure as well as thickness disparities of up to 50% in the vertical sample. Atomic force microscopy showed roughness, Ra, varied from 0.37 nm to 15.4 nm between samples. Raman spectroscopy highlighted variations in the sp2/sp3 bonding ratios whilst micro wear tests demonstrated how these variations reduce the critical load performance. These effects are explained in terms of the deposition mechanisms involved and are related to variation in deposition species and geometrical field enhancements within the deposition chamber. Improved understanding of these local variations will aid in the optimisation of coatings for complex substrate geometries.

Crystallography, Cristallographie cristallogenèse, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure, proprietes mecaniques et thermiques, Condensed matter: structure, mechanical and thermal properties, Surfaces et interfaces; couches minces et trichites (structure et propriétés non électroniques), Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties), Structure et morphologie de couches minces, Thin film structure and morphology, Structure et morphologie; épaisseur, Structure and morphology; thickness, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Méthodes de dépôt de films et de revêtements; croissance de films et épitaxie, Methods of deposition of films and coatings; film growth and epitaxy, Théorie et modèles de la croissance de films, Theory and models of film growth, Sciences appliquees, Applied sciences, Electronique, Electronics, Appareillage électronique et fabrication. Composants passifs, circuits imprimés, connectique, Electronic equipment and fabrication. Passive components, printed wiring boards, connectics, Alcool, Alcohols, Alumine, Alumina, Boehmite, Boehmita, Capacité électrique, Capacitance, Condensateur, Capacitors, Couche barrière, Barrier layer, Couche mince, Thin films, Cristallisation, Crystallization, Diffraction RX, XRD, Ethane-«1,2»-diol, Ethylene glycol, Mesure capacité électrique, Capacitance measurement, Morphologie surface, Surface morphology, Mécanisme croissance, Growth mechanism, Mecanismo crecimiento, Propriété diélectrique, Dielectric properties, Traitement surface, Surface treatments, 6855A, 6855J, 8115A, 8432T, Al2O3, Substrat Aluminium, Anodic alumina, Dielectric, and Surface treatment

Hydrous films were grown on high purity and cubicity Al foils for electrolytic capacitors in deionized water, ethylene glycol-deionized water and glycerol-deionized water at different immersion times. According to X-ray diffraction patterns the hydration treatment allowed growing a pseudo boehmite layer on Al surface whose morphology is appreciably affected by the bath composition. Capacitance measurements and photoelectrochemical findings suggest that a more compact barrier layer forms during the immersion in alcohol containing solutions. The hydration in water allowed saving energy and preparing more blocking oxide films. The beneficial effect of hydration in hot water on the specific capacitance was evidenced only for films formed at 300 V due to the crystallization of amorphous alumina in γ'-Al2O3.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Corrosion, Action des agents de corrosion, Corrosion environments, Alliage base aluminium, Aluminium base alloys, Corrosion, Dépôt conversion, Conversion coating, Depósito conversión, Konversionsbeschichten, Revêtement, Coatings, Température, Temperature, Traitement surface, Surface treatments, Aluminum 2024, Nanosilica, and Silicate conversion coatings

Nanosilica modified potassium silicate conversion coatings were deposited on the surface of 2024 aluminum alloy. The corrosion behavior of coatings was studied by electrochemical impedance spectroscopy, potentiodynamic polarization and the surface analyzing techniques. The effect of curing time and the curing temperature was studied on anti-corrosion behavior of coatings. Curing temperature showed a significant effect in silicate conversion coating and higher corrosion resistance was obtained with 150 °C curing temperature. Also the experimental results indicated that the corrosion resistance was increased with increasing the curing time. This behavior can be related to the increase of the silicate coating continuity and reinforcement of the siloxane chains which formed on the surface. Surface analysis results indicated that the coating obtained from 2.33 silica ratio was more uniform and continuous.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Propriétés mécaniques. Rhéologie. Mécanique de la rupture. Tribologie, Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology, Alliage base magnésium, Magnesium base alloys, Dépôt projection, Spray coatings, Matériau composite, Composite materials, Projection à chaud, Hot spraying, Proyección en caliente, Spritzen, Propriété mécanique, Mechanical properties, Revêtement composite, Composite coating, Revestimiento compuesto, Traitement surface, Surface treatments, Cold spray, Magnesium alloys, and Mechanical property

Although many previous studies have confirmed that cold sprayed Al + xAl2O3 (x = 0―75 vol.%) composite coatings on magnesium alloys can effectively improve wear and corrosion resistance, the effect of such coatings on tensile and fatigue properties is still unclear. The present work aims to evaluate the tensile properties and fatigue resistance of an AZ91D alloy with cold sprayed Al + xAl2O3 (x = 0,30, 50 vol.%) coatings. The experimental results showed that although the cold spray coating leads to an increase in yield strength and fatigue limit, the tensile strength is reduced. In-situ examination of the macro-morphology of surfaces of the coated specimens during tensile testing was carried out through video recording. It indicated that once the tensile specimens have yielded, horizontal cracks that were perpendicular to the tensile axis formed on the surface of the specimens. Fractographic analysis of the fracture surfaces of the tensile specimens in a scanning electron microscope revealed that all the cracks within the cold sprayed coatings were suspended at the coating/substrate interface. Based on these experimental observations, it is considered that the improved yield strength is attributed to the constraint effect of the cold sprayed composite coatings on the magnesium substrate. The enhanced fatigue limit is a result of the higher yield strength and the coating/substrate interface barrier to crack propagation. The decrease in tensile strength is attributed to the brittle fracture of the cold sprayed coatings when yielding of the specimens.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Propriétés mécaniques. Rhéologie. Mécanique de la rupture. Tribologie, Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology, Frottement. Usure, Contact of materials. Friction. Wear, Propriété mécanique, Mechanical properties, Oxyde de titane, Titanium oxide, Titanio óxido, Titanoxid, Procédé sol gel, Sol-gel process, Température, Temperature, Traitement surface, Surface treatments, Tribologie, Tribology, Usure, Wear, CP-Ti, Calcination, Sol-gel, and TiO2

Commercially pure titanium (CP-Ti) is commonly used as an implant material especially for orthopedic and dental treatments in biomedical applications. This material shows insufficient tribological properties. Some surface treatments were applied on surface CP-Ti in order to improve tribological properties of the CP-Ti. Among these techniques, sol-gel coating process was used for this purpose. In this study, CP-Ti was coated by TiO2 film with sol-gel dip coating process. Coated samples were calcined at the various temperatures. The effects of calcination temperature on the wear performance of the coated films were observed. It was observed that the hardness, elastic modulus, surface roughness, friction coefficient and wear resistance values of coated samples were higher than the uncoated CP-Ti values. Also, these properties of coated samples increased with increasing of calcination temperature. The intensity of the rutile-TiO2 phase increased with the calcination temperatures. It was determined that rutile-TiO2 structure showed self-lubrication like behavior. The best tribological properties were obtained from the sample calcinated at 900 °C.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Autres traitements de surface, Other surface treatments, Alliage base aluminium, Aluminium base alloys, Anodisation, Anodizing, Conception, Design, Couche oxyde, Oxide layer, Capa óxido, Oxidschicht, Microstructure, Oxydation, Oxidation, Oxyde anodique, Anodic oxide, Traitement surface, Surface treatments, Vieillissement, Aging, Aluminum anodizing, Bath aging, Oxide layer microstructure, and Pore design

During the aluminum anodization the anodizing electrolyte changes over time and is well-known as bath aging. This alteration of the bath is mainly caused by the impact of Al3+ ions and ions of alloying elements as well as the consumption of protons. It is shown that the higher the Al3+ concentration the higher the pH value and the electrical resistance of the bath. Consequently, the oxide formation rate decreases, whereby the efficiency of layer formation increases. This work is focused on the effect of the ongoing bath aging on the microstructure of the anodic oxide layers formed on AA1050. It illustrates the fact that the ongoing bath aging significantly influences the morphology, the thickness and the pore structure of the oxide layers that are formed, but does not influence the barrier layer thickness. The pore diameter decreases with ongoing bath aging. As a direct consequence the hardness of the oxide layer increases and the pore diameter decreases.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Air, Alliage base nickel, Nickel base alloys, Développement, Ontogenesis, Microstructure, Oxydation, Oxidation, Pile combustible oxyde solide, Solid oxide fuel cells, Revêtement, Coatings, Superalliage, Superalloys, Traitement surface, Surface treatments, Electron microscopy, Nickel base superalloy, and Solid oxide fuel cell interconnects

The effect of reactively sintered Mn1.5Co1.5O4 (MCO) coatings on the development of surface microstructure for Haynes 230 (H230) oxidized in air at 800 °C has been studied using a combination of thermo-gravimetric analysis and electron microscopy techniques. The bare alloy exhibits a parabolic rate constant of 8.8 × 10―9 mg2cm―4 s―1 and forms a two-layer oxide scale with a continuous chromia layer and a thinner discontinuous MnCr2O4 overlayer. For the MCO-coated H230, the reduction step of the reactive sintering process converts the MCO coating to a mixture of Co and MnO with a thin Cr-rich oxide layer at the interface with the alloy substrate. Following the re-oxidation step, there is a 200 nm chromia layer and a 400 nm cubic spinel reaction layer (RL) between the alloy and the MCO. These layers thicken to 800 nm and 1.2 μm, respectively after 1000 h oxidation. These observations are compared to our previous studies of MCO-coated Crofer 22 APU, and the implications for long-term SOFC performance are discussed.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Dépôt de matériaux non métalliques, Nonmetallic coatings, Céramique, Ceramics, Oxydation, Oxidation, Oxyde de zirconium, Zirconium oxide, Zirconio óxido, Zirconiumoxid, Plasma, Revêtement non métallique, Non metal coating, Revestimiento no metálico, Nichtmetallischer Ueberzug, Traitement surface, Surface treatments, Ceramic coating, PEO, Plasma electrolytic oxidation, and Pure zirconium

The pure zirconium metal was coated by plasma electrolytic oxidation in silicate containing basic electrolyte for the cumulative periods of 5, 10, 20, 30, 45, 60, 90, and 120 min successively for the total coating duration of 120 min. The phase content, surface morphology and chemical composition of the PEO coating were characterized by XRD, SEM and profilometry after each coating time successively. The equiaxed clusters unique to Zr were formed on the surface of the coating. The number of plasma channels decreased but the sizes and intensities of the sparks increased by increasing the process duration and consequently the amount of materials ejaculated through these channels increased. The thickness and the surface roughness of the coating were increased by the process duration. The presence of cracks and pores resulted in a lower value of microhardness of the coating compared to the theoretical value of ZrO2. The plasma channels containing Si rich and radially grown Zr rich crystals were clearly observed from the cross sectional examination of intentionally created fracture surface. The characterizations carried out upon successive coating and successive removal of this coating confirmed that monoclinic ZrO2/tetragonal ZrO2 ratio was not changing with coating thickness.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Corrosion, Action des agents de corrosion, Corrosion environments, Adhérence, Adhesion, Corrosion, Dépôt physique phase vapeur, Physical vapor deposition, Magnétron, Magnetrons, Pulvérisation irradiation, Sputtering, Résistance corrosion, Corrosion resistance, Traitement surface, Surface treatments, High power pulsed magnetron sputtering, Tensile strain, and Ti-O film

In order to explore the potential application on cardiovascular stent, titanium oxide films were fabricated on CoCrMo alloy substrate by high power pulsed magnetron sputtering (HPPMS). The effect of Ti interlayer and thickness of Ti-O film on the film adhesion was investigated by the scratch test and tension test. After different tensile strain, the corrosion behavior of Ti-O coated CoCrMo alloy and bare CoCrMo alloy was also investigated by polarization tests. The results showed that the deposition of Ti interlayer can obviously improve the film adhesion and the film adhesion decreased with film thickness increase. In addition, the 30 nm Ti-O film with 10 nm Ti interlayer had excellent adhesion and it could withstand 30% relative elongation without obvious delamination. The corrosion resistance of Ti-O coated CoCrMo alloy was superior to bare CoCrMo alloy after different tensile strain. Due to its good adhesion and corrosion resistance after different tensile strain, the HPPMS Ti-O film had a potential application on CoCrMo alloy cardiovascular stent surface modification.