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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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Dépôt de matériaux non métalliques, Nonmetallic coatings, Composé organique, Organic compounds, Compuesto orgánico, Organische Verbindung, Décharge luminescente, Glow discharge, Descarga luminiscente, Glimmentladung, Imide polymère, Polyimide, Imida polímero, Plasma, Revêtement non métallique, Non metal coating, Revestimiento no metálico, Nichtmetallischer Ueberzug, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, and Organic coating

In this work the deposition of thin films of polyimide precursor monomers through glow discharge-induced sublimation (GDS) has been performed. The selected monomers were 2,4,6-trimethyl m-phenylenediamine (TMPD), 3,3'-diaminodiphenyl sulfone (DDS), 4,4'-hexafluoroisopropylidene dianiline (6FDAm), 3,3',4,4'-biphenyltetracarboxylic acid dianhydride (BPDA) and 4,4'-hexafluoroisopropylidene diphthalic anhydride (6FDA). The surface of the deposited films has been studied by X-ray photoelectron spectroscopy (XPS) in order to attain a better knowledge of the molecular damage induced by the plasma/monomer interactions and of the incorporation of molecular fragments into the deposited films. Different damage mechanisms are found due to the different molecular structure.

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Dépôt de matériaux non métalliques, Nonmetallic coatings, Chrome nitrure, Chromium nitride, Cromo nitruro, Chromnitrid, Couche mince, Thin film, Capa fina, Duennschicht, Dépôt physique phase vapeur, Physical vapor deposition, Deposición física fase vapor, Physikalisches Aufdampfen, Nitrure, Nitrides, Nitruro, Nitrid, Plasma, Revêtement non métallique, Non metal coating, Revestimiento no metálico, Nichtmetallischer Ueberzug, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, CrN thin films, ESCA, Physical vapour deposition (PVD), and XPS

Cr-N film coatings were prepared by magnetron sputter deposition at different nitrogen partial pressures. The film characterisation by XRD and DTG gives average bulk compositions of Cr2N and CrN for the coatings. Highly sensitive XPS investigations were performed and the chemical and phase compositions of a film surface range of about 10 nm thickness was estimated quantitatively from the deconvoluted peak intensities. It is demonstrated that the composition of the surface of chromium nitride thin films differs from the core and is more complex in constitution. Not only chromium nitrides (Cr2N and CrN) but also chromium oxynitrides and chromium oxides (CrOxand CrOxHy) were detected. Metallic chromium was also found in films prepared at higher nitrogen flow. The concentration of the estimated phases shows dependence on film preparation and additional heat treatment.

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Dépôt de matériaux non métalliques, Nonmetallic coatings, Propriétés mécaniques. Rhéologie. Mécanique de la rupture. Tribologie, Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology, Acier outil, Tool steel, Acero herramienta, Werkzeugstahl, Analyse contrainte, Stress analysis, Análisis tensión, Spannungsanalyse, Chrome nitrure, Chromium nitride, Cromo nitruro, Chromnitrid, Contrainte résiduelle, Residual stress, Tensión residual, Eigenspannung, Diffraction RX, X ray diffraction, Difracción RX, Roentgenbeugung, Dépôt physique phase vapeur, Physical vapor deposition, Deposición física fase vapor, Physikalisches Aufdampfen, Multicouche, Multiple layer, Capa múltiple, Mehrfachschicht, Nanostructure, Nanoestructura, Nitrure, Nitrides, Nitruro, Nitrid, Plasma, Propriété mécanique, Mechanical properties, Propiedad mecánica, Propriété élastique, Elastic properties, Propiedad elástica, Revêtement multicouche, Multilayer coating, Revestimiento multicapa, Revêtement non métallique, Non metal coating, Revestimiento no metálico, Nichtmetallischer Ueberzug, Titane nitrure, Titanium nitride, Titanio nitruro, Titannitrid, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Multilayer, Residual stresses, X-ray diffraction, and nanostructure

Thin multilayer films, especially nitrides of transition metal, exhibit hardness enhancements that are significantly higher than those predicted by the rule of mixtures. In this study, TiN/CrN multilayers, consisting of alternating nanometer-scale TiN and CrN layers, were deposited by arc evaporation technique on M2 steel. Different period thicknesses A have been prepared: 10, 20, 40 and 60 nm. A recent study has shown that tribological properties enhancement of hard PVD nanostructured nitride coatings deposited on tool steel is optimum for a special period value of 40 nm with thicknesses of 24 and 16 nm for CrN and TiN layers, respectively. In order to get a better understanding of the mechanical behaviour of the coatings as a function of the modulation wavelength A, residual stresses in each nitride systems have been characterized using X-ray diffraction and the sin2ψ method at a synchrotron radiation facility. It is shown that the stresses are compressive and their magnitudes vary according to the type of nitride: CrN is less stressed than TiN. This might explain why the propagation of cracks into the whole multilayer coating is governed by the interfaces.

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Dépôt de métaux et d'alliages, Metallic coatings, Dépôt de matériaux non métalliques, Nonmetallic coatings, Propriétés mécaniques. Rhéologie. Mécanique de la rupture. Tribologie, Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology, Ailette, Fin, Aleta, Analyse contrainte, Stress analysis, Análisis tensión, Spannungsanalyse, Contrainte résiduelle, Residual stress, Tensión residual, Eigenspannung, Diamant, Diamond, Diamante, Diffraction RX, X ray diffraction, Difracción RX, Roentgenbeugung, Nanostructure, Nanoestructura, Plasma, Propriété mécanique, Mechanical properties, Propiedad mecánica, Propriété élastique, Elastic properties, Propiedad elástica, Revêtement métallique, Metal coating, Revestimiento metálico, Metallischer Ueberzug, Revêtement non métallique, Non metal coating, Revestimiento no metálico, Nichtmetallischer Ueberzug, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, B Elastic properties, B X-ray diffraction, D Diamond: D nanostructure, D Titanium alloy, and X Residual stresses

A mechanical and micro structural characterization has been done in diamond coating deposited on TA6V titanium alloys using X-ray diffraction. The CVD deposition process used allows elaborating layers at moderated temperature (600 °C). Varying the precursor gas composition, the purity level (sp3), the morphology (columnar or fine grains) and the roughness of the polycrystalline layers may be changed. Stress measurements indicate that diamond layer is under huge compression (3-6 GPa) as well as the intermediate TiC1-x layer but with a lower stress magnitude (< 1 GPa) whatever the deposition parameters. A good agreement is found between X-ray and Raman diamond stress values except for the low purity layers where the Raman values are lower than the X-ray ones. This discrepancy is certainly related to the elastic modulus softening evidenced by Brillouin scattering and nanoindentation which has not been taken into account for the X-ray evaluation. Furthermore, a <110> fiber texture has been observed in thick columnar grain coatings and also in low purity fine grain coatings; the texture intensity is weaker for this last coating morphology.

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, 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, Propiedad mecánica, Acier inoxydable martensitique, Martensitic stainless steel, Acero inoxidable martensítico, Martensitischer nichtrostender Stahl, Acier inoxydable, Stainless steel, Acero inoxidable, Nichtrostender Stahl, Acier martensitique, Martensitic steel, Acero martensítico, Martensitischer Stahl, Plasma, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Tribologie, Tribology, Tribología, Usure, Wear, Desgaste, Verschleiss, GDOS, PIII, and XRD

Martensitic stainless steel samples-1.4021 (X20Cr13), 1.4034 (X46Cr13), 1.4057 (X17CrNil6.2), 1.4104 (X14CrMoS17) and 1.4542(X5CrNiCuNb17.4)-were implanted with nitrogen using plasma immersion ion implantation (PIII) at different temperatures between 320 and 380 °C and at different pulse voltages for up to 3 h. The formation of an expanded martensite layer was found after implantation for all samples with a surface martens hardness of up to 10,000 N/mm2. The wear was measured in a dry ball-on-disc configuration. The specific wear was reduced by a factor of 2-10 to the same absolute level as for expanded austenite. With increasing contact pressure, an increased wear rate was found, while no influence of the speed was observed.

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, 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, Frottement. Usure, Contact of materials. Friction. Wear, Propriété mécanique, Mechanical properties, Propiedad mecánica, Acier non allié, Carbon steel, Acero no aliado, Unlegierter Stahl, Alumine, Alumina, Alúmina, Tonerde, Coefficient frottement, Friction coefficient, Coeficiente roce, Reibungskoefficient, Corrosion, Corrosión, Korrosion, Frottement, Friction, Frotamiento, Reibung, Plasma, Projection flamme, Flame spraying, Proyección llama, Flammspritzen, Titane oxyde, Titanium oxide, Titanio óxido, Titanoxid, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Tribologie, Tribology, Tribología, Usure, Wear, Desgaste, Verschleiss, Al2O3-TiO2, and Flame spray

In this study, Al2O3-TiO2 powders were sprayed using a flame-spray technique after a NiCrMo bond layer was deposited on plain carbon steel substrate. The produced layers were characterized by X-ray diffraction (XRD), optical microscope, scanning electron microscope (SEM) including energy-dispersive spectroscopy (EDS), surface roughness and microhardness tester. Friction and wear behaviour of the coatings were also evaluated in the present study. The Al2O3-TiO2 coatings were subjected to sliding wear against AISI 303 stainless steel counter body under dry and acidic environments. A pin-on-plate type apparatus was used with normal loads in the range of 49-129 N. Wear resistance of the coatings in acid environment is better than that in dry conditions.

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Métallurgie des poudres. Matériaux composites, Powder metallurgy. Composite materials, Poudres métalliques, Metal powders, Traitements de surface, Surface treatment, Propriétés mécaniques. Rhéologie. Mécanique de la rupture. Tribologie, Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology, Alliage mécanique, Mechanical alloying, Aleación mecánico, Mechanisches Legieren, Carbone, Carbon, Carbono, Kohlenstoff, Couche mince, Thin film, Capa fina, Duennschicht, Effet composition, Composition effect, Efecto composición, Konzentrationseinfluss, Lubrification, Lubrication, Lubricación, Schmieren, Métallurgie poudre, Powder metallurgy, Metalurgia polvo, Pulvermetallurgie, Plasma, Propriété mécanique, Mechanical properties, Propiedad mecánica, Pulvérisation irradiation, Sputtering, Pulverización irradiación, Sputtern, Revêtement, Coatings, Revestimiento, Ueberzug, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Tribologie, Tribology, Tribología, Self-lubrication, Tribological coatings, Tungsten disulphide, and WS2

In this work, W-S-C films were deposited by both a reactive process in an Ar+CH4 atmosphere and co-sputtering WS2 and C targets. The chemical and physical characterization showed that the properties of the W-S-C films are very similar for both systems. The films without and with low C content have columnar appearance, which develops to a very compact featureless morphology for the highest C-alloyed films. The WS2 phase was detected for low alloyed films. In reactive deposited films, there was a loss of crystallinity with increasing C content. The films co-sputtered with C are amorphous. The evolution of the hardness and adhesion with increasing C-content follows a similar trend in the films deposited by both processes: they increase with C content.

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Application, Aplicación, Anwendung, Couche mince, Thin film, Capa fina, Duennschicht, Dureté, Hardness, Dureza, Haerte, Nanostructure, Nanoestructura, Plasma, Pulvérisation irradiation, Sputtering, Pulverización irradiación, Sputtern, Revêtement, Coatings, Revestimiento, Ueberzug, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Nanostructures, and W-B-N coatings

The structure, composition and hardness of reactively sputtered W-B-N thin films were investigated by XRD, EPMA, and Vickers ultramicroindentation. The chemical composition of the films was changed from W80B20 to W42B9N49by varying the partial pressure of N2. All the as-deposited coatings were amorphous, except the W60B17N23 film, which showed crystalline peaks, indexed as bcc α-W, overlapping the amorphous feature. This nanocomposite structure lead to a maximum as-deposited hardness of 36 GPa. The coatings were thermally annealed at 850 and 950 °C in Ar/H2 atmosphere. All the films crystallised with the formation of the bcc α-W and/or the fcc-W2N phases, depending on their B and N contents. A small increase in hardness was registered for 850 °C annealing temperature in comparison to the as-deposited state. However, an inverse trend was detected after post-annealing at 950 °C, which was more evident for the high N content films. This behaviour was attributed to the formation of a soft external layer of boron nitride poorly crystallised.

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Dépôt chimique phase vapeur, Chemical vapor deposition, Depósito químico fase vapor, Chemisches Aufdampfen, Plasma, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Equipment, PECVD, Silicon dioxide, and VHF excitation

Different principal types of plasma-enhanced chemical vapour deposition (PECVD) processes of silicon oxides are used: the conventional RF (13.56 MHz) PECVD, remote PECVD, inductive coupled high density plasma CVD and veryhigh frequency (VHF) PECVD. Single-wafer chambers with parallel-plate PECVD systems are expected to be the mainstream for the future for PECVD processes. Equipment and process improvements include activities to improve wafer throughput and film uniformity and to eliminate plasma damage to layers and devices. Increasing the excitation frequency from the commonly used 13.56 MHz up to the lower VHF range (40-80 MHz) has demonstrated higher deposition rates with good electronic film properties. A single-wafer parallel-plate PECVD system was developed using a 40.68 MHz excitation. The wafer temperature is controlled by a helium back side flush avoiding also a deposition at the wafer back side. A stable plasma confined between the electrodes away from the walls of the chamber, an optimised plasma density to get a sufficient deposition rate and good film uniformity, and a controlled wafer temperature which influences the plasma-surface interaction were achieved. Using a SiH4/N2O process and a deposition rate of 1 nm/s a high breakdown voltage ≥6 MV/cm and a refractive index of 1.46 ′ 0.015 were obtained. Film thickness uniformity was <5%. A SF6/O2 process is used for the reactor cleaning with etching rates of about 1 nm/s.

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Dépôt sous vide, Vacuum deposition, Depósito bajo vacío, Vakuumbeschichtungsverfahren, Plasma, Revêtement dur, Hard coating, Revestimiento duro, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Plasma filter, and Vacuum arc

Vacuum arc deposition is a commonly used technology for the deposition of hard coatings and all kinds of metals. The vacuum arc discharge is a simple source of highly ionized metal plasma. Films with a very dense structure and an excellent adhesion can be produced because of the high ion energy inside the vacuum arc plasma. But also a certain number of macroparticles is emitted and deposited. That is why a great number of particle filters was developed in the past, but no one of them has larger industrial usage. A very simple but effective filter design is the Venetian blind filter. The macroparticles are shielded from the substrate but the plasma is guided through the filter by means of magnetic and electric fields. With this type of filter, films with a dramatically reduced number of droplets can be produced. A plasma transmission through the filter of approximately 20% could be reached. Micrographs of the film surfaces were analyzed by a certain method to investigate the droplet distribution in number and size for different materials. A reduction of the droplet number down to 10%-1% of the unfiltered case could be determined. A filter unit for using at the most common vacuum arc deposition machines was developed and tested and is now available. The filter does not reduce the deposition area, so the standard deposition processes can be used furthermore. The filter is in use for metal deposition. A process for the production of hard coatings as metal nitride films is under development. Such particle reduced coatings are especially appropriate for the surface protection of tools with high demands of surface smoothness and precision, for example forming tools for high precision parts. The fields of application of the vacuum arc technology can be enlarged by means of this type of plasma filter. The advantages of this filter are the good handling properties and the possibility of retrofitting existing arc coaters.

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Carbone, Carbon, Carbono, Kohlenstoff, Couche mince, Thin film, Capa fina, Duennschicht, Hydrocarbure fluoré, Fluorocarbon, Hidrocarburo fluorado, Plasma, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, 33.60.Fy, 52.40.Hf Domains, 68.03.Cd, 68.37.Ps, 82.33.Xj, 82.35.Gh, 82.35.Lr, and Plasma polymerization

In conventional plasma polymerization processes, the bulk properties of the treated substrates are maintained whereas the surface properties are changed to the ones of the coating polymer. In contrast, materials with ultrathin non-closed layers and domains of plasma deposited compounds can show combined properties (from the surface of the bulk material and the non-closed layer) or even completely new behavior. This can be seen by analyzing e.g. the wettability (contact angle), the tribological properties, chemical functionalities or biological interactions. Ultrathin closed and non-closed films (domains) of fluorocarbon polymer were produced by means of RF-CVD (radio frequency aided chemical vapor deposition, plasma polymerization) with CHF3 as monomer gas; argon was added as additional process gas. Our work has been carried out in a symmetric capacitively coupled reactor at 13.56 MHz in the low-pressure, glow-discharge regime. The influence of pulsing the plasma by varying on- and off-times on the surface properties were investigated on silicon wafers as substrates. The obtained functionalized surfaces were characterized by means of advancing and receding contact angle measurements, X-ray photoelectron spectroscopy (XPS) as well as atomic force microscopy (AFM).

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Carbone, Carbon, Carbono, Kohlenstoff, Couche mince, Thin film, Capa fina, Duennschicht, Diamant synthétique, Synthetic diamond, Diamante sintético, Dépôt sous vide, Vacuum deposition, Depósito bajo vacío, Vakuumbeschichtungsverfahren, Etat amorphe, Amorphous state, Estado amorfo, Amorpher Zustand, Mouillage, Wetting, Remojo, Plasma, Structure diamant, Diamond structure, Estructura diamante, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Carbon films, DLC, Ultra hydrophobic surface, and Vacuum-arc-deposition

Carbon films are distinguished by their broad structural variability and a correspondingly wide range of properties varying from diamond-like to graphite-like. This variability is determined by the relation of diamond bonds (sp3) to graphitic bonds (sp2) and can be influenced by addition of other elements. The highest degree of diamond-likeness, e.g. expressed by high hardness, is achieved in pure carbon films. Such super hard films, so-called tetrahedral bonded amorphous carbon films (ta-C), reach a hardness from 40 GPa up to 80 GPa and a Young's modulus from 400 GPa up to 800 GPa. By incorporation of additional elements, not only the mechanical properties but also the surface energy can be varied. PTFE-like properties can be obtained by addition of fluorine or other elements. At Fraunhofer IWS Dresden such doped amorphous carbon films (a-C:X) have been deposited by a special pulsed vacuum-arc technique, the laser-induced pulsed arc (Laser-Arc). The deposition process is characterized by producing a high activated carbon plasma from a pure or doped graphite cathode and its deposition on substrates under vacuum or reactive conditions. The mechanical properties of the doped a-C:X-films were investigated in dependence on the content of the doped elements. Furthermore, the surface energy was determined by means of contact angle measurements. To get ultra hydrophobic properties of a surface additionally to a low surface energy a defined structuring of the surface topography is necessary. Different kinds of such structuring methods and their effects in conjunction with a doped a-C:X-film on the super hydrophobic behaviour are shown.

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Implantation ion, Ion implantation, Implantación ión, Ionenimplantation, Microstructure, Microestructura, Mikrogefuege, Plasma, Texture, Textura, Textur, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Homogeneity, MePIIID, TiN, and XRD

The spatial texture evolution and variation across a sample holder (6 cm diameter) was investigated for titanium nitride thin films deposited by metal plasma immersion ion implantation and deposition (MePIIID). With increasing pulse voltage from - 1 to - 10 kV and increasing pulse frequency, a transition of the texture from [111] via [220] to [200] was observed. Here, the product of pulse frequency and voltage is determining the texture, with the slight dependence of the fluence per pulse on the voltage as a minor correction. Near the edge of the samples, a tilt of the crystallites was observed. For high frequencies, an equilibrium position was observed, while a gradual decrease of the tilt with lower frequencies is present. Apparently, the orientation of the grains along the ion incidence direction is a dynamic process requiring a certain minimum energy input for a complete transformation.

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Chrome nitrure, Chromium nitride, Cromo nitruro, Chromnitrid, Nanoparticule, Nanoparticle, Nanopartícula, Plasma, Revêtement, Coatings, Revestimiento, Ueberzug, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Tribologie, Tribology, Tribología, Carbon, and Nanoparticles

CrN is well known to be one of the most performing tribological coatings, with excellent wear and corrosion resistance and good toughness. These last two properties could make CrN a promising base for the development of coatings for high pressure contacts in lubricated conditions. Unfortunately, like most other nitrides, its dry friction coefficient is not very low. In this work we present the results of a series of experiments aimed at investigating the effect of the incorporation of carbon nanoparticles (nC) on the tribological properties of CrN, in order in particular to check the possibility of achieving a lower dry friction coefficient. Taguchi DoE technique was used to define the set of experiments to be performed; the analysis shows that only minor changes in both dry and lubricated friction coefficient can be obtained within the range of deposition parameters investigated while microhardness is sensitive to variations of the deposition pressure.

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Application médicale, Medical application, Aplicación medical, Medizinische Technik, Biomatériau, Biomaterial, Dureté, Hardness, Dureza, Haerte, Implant, Implante, Implantation ion, Ion implantation, Implantación ión, Ionenimplantation, Plasma, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Tribologie, Tribology, Tribología, GD-OES, and Ion Implantation

This work reports a comparative investigation on tribological performance enhancement induced by nitrogen Plasma Immersion Ion Implantation (PI3) and conventional Nitrogen Ion Implantation (I2) on Ti and Al based alloys.The study has been carried out on the basis of the surface modification produced by both treatment techniques, in terms of the implanted nitrogen in-depth profiles, and its effect on surface hardening and wear resistance increase of the treated samples. Under the experimental conditions described, PI3 Ti-based alloys treated samples evidenced slightly better tribological performance than those subjected to I2 treatments. In the case of Al alloys, however, PI3 caused strong detrimental modification on the treated samples as revealed in the increase by a factor 100 of its surface roughness. Consequently, different criteria should be deemed in order to establish the adequacy of one or other technique, not only taking into account set up costs but also considering specific applications.

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, 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, Coefficient frottement, Friction coefficient, Coeficiente roce, Reibungskoefficient, Couche mince, Thin film, Capa fina, Duennschicht, Frottement, Friction, Frotamiento, Reibung, Plasma, Propriété mécanique, Mechanical properties, Propiedad mecánica, Pulvérisation irradiation, Sputtering, Pulverización irradiación, Sputtern, Revêtement dur, Hard coating, Revestimiento duro, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Tribologie, Tribology, Tribología, Usure, Wear, Desgaste, Verschleiss, Hard coatings, Tribological behaviour, W-Ti-N sputtered films, and Wear and friction coefficients

W-Ti-N thin films were deposited with increasing N contents by dc magnetron sputtering a W80-Ti20 (wt.%) target using nitrogen as reactive gas. The coatings were deposited without (Vs = - 70V) and with assistance of an ion gun (Vs= -40V). The hardness was improved with increasing N content up to -43 at.%, decreasing thereafter. The critical load values showed an inverse trend. The coatings presenting the lowest wear rate (<10-15 m3/N m) and friction coefficient (∼0.4) were deposited in both series with N contents close to 40-43 at.%. It was not possible to correlate the wear behaviour to one single parameter; however, either the compromise of a good hardness and adhesion or a low friction coefficient can in different cases explain the wear resistance. The wear results were interpreted as a function of the type of transfer material in the sliding contact.

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Plasma, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Elastomer, Self-organization, and Silicone

Silicone surfaces are known to form a nano-structured surface topography after irradiation in superposition with mechanical strain [P. Bodö, J.-E. Sundgren, Thin Solid Films 136 (1986) 147; N. Bowder, W.T.S. Huck, K.E. Paul, G.M. Whitesides, Appl. Phys. Lett. 75 (1999) 2557; F. Katzenberg, Macromol. Mater. Eng. 286 (2001) 26.]. Uniaxially strained polydimethylsiloxane (PDMS) was exposed to argon plasma. This treatment results in highly regular surface undulations. The dimensions of the resulting surface topography were studied with dependence on the process parameters. The wavelength (horizontal structure dimension) of the undulations depends mainly on the plasma energy, whereas the amplitude (vertical structure dimension) is essentially influenced by the degree of strain during treatment. So far, minimal wavelengths of 100 nm have been achieved with amplitudes of 25 nm.

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Carbone, Carbon, Carbono, Kohlenstoff, Couche mince, Thin film, Capa fina, Duennschicht, Plasma, Polymère, Polymer, Polímero, Spectrométrie SIMS, Secondary ion mass spectrometry, Espectrometría SIMS, Sekundaerionenmassenspektrometrie, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Plasma polymer films, Principal component analysis (PCA), and ToF-SIMS

In order to create nano-functional fluorocarbon films (CFx films), silicon and polyethylene terephthalate (PET) substrates have been exposed to a pulsed Ar/CHF3 plasma by variation of the deposition time from 10-90 s. The deposited CFx films were analysed using time of flight secondary ion mass spectrometry (ToF-SIMS) and principal component analysis (PCA). Changes in the surface composition and molecular distribution have been detected and correlated to results from additional XPS measurements. The results show differences in film growth and CFx cross-linking for the silicon and PET substrates. In this analysis we demonstrate that ToF-SIMS and multivariate analysis is a very useful combination for thin film characterisation.

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Couche mince, Thin film, Capa fina, Duennschicht, Couche oxyde, Oxide layer, Capa óxido, Oxidschicht, Dépôt chimique phase vapeur, Chemical vapor deposition, Depósito químico fase vapor, Chemisches Aufdampfen, Etain oxyde, Tin oxide, Estaño óxido, Zinnoxid, Laser, Láser, Microstructure, Microestructura, Mikrogefuege, Oxydation, Oxidation, Oxidación, Plasma, Titane nitrure, Titanium nitride, Titanio nitruro, Titannitrid, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Gas sensor, Laser-assisted MOCVD, Tin dioxide, and XPS

Amorphous and polycrystalline tin oxide (SnO,) thin films were grown by ArF excimer laser-induced metal-organic chemical vapour deposition (L-MOCVD) from tetramethyltin (TMT) and oxygen as precursors. The films structure and composition were investigated by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The deposition temperature and the ratio of the TMT and oxygen flow rates have been optimised in order to minimise the residual carbon content and to achieve stoichiometric SnO2 films. The films deposited at room temperature were amorphous, strongly substoichiometric [O]:[Sn]=1.3 and with a high residual carbon content depending on the TMT and oxygen ratio. Films grown at 300 °C were polycrystalline with [O]:[Sn] ratios up to 1.8 and with a much lower carbon content. The tin oxide films were subsequently used as sensing layers for gas detection. A satisfactory sensor performance was obtained for the oxidising NO2 and the reducing N2O, CH4, SO2, CO, CO2, H2 gases.

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, Divers, Other topics in materials science, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Propriétés mécaniques. Rhéologie. Mécanique de la rupture. Tribologie, Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology, Facteur intensité contrainte, Stress intensity factor, Factor intensidad tensión, Spannungsintensitaetsfaktor, Fissure interne, Internal crack, Fisura interna, Innenriss, Modélisation, Modeling, Modelización, Méthode élément frontière, Boundary element method, Método elemento frontera, Plasma, Propriété mécanique, Mechanical properties, Propiedad mecánica, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Film/substrate, Internal cracks, Sliding contact, and Stress intensity factors

Using boundary elements based on the three-dimensional modelling for linear fracture mechanics, we present an analysis of cracking in a coated specimen subject to contact load. The initial cracks are assumed to lie entirely within the film or the substrate. It is shown that the most probable direction of propagation of a vertical internal crack of fixed size is strongly dependent on its location with respect to the axis of maximum normal load and the free surface.