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Chemical industry parachemical industry, Industrie chimique et parachimique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Technologie des polymères, Technology of polymers, Formes d'application et semiproduits, Forms of application and semi-finished materials, Fibres et fils, Fibers and threads, Dépôt plasma, Plasma deposition, Depósito plasma, Ethylène(tétrafluoro) polymère, Tetrafluoroethylene polymer, Etileno(tetrafluoro) polímero, Etude expérimentale, Experimental study, Estudio experimental, Fibre naturelle, Natural fiber, Fibra natural, Matériau revêtu, Coated material, Material revestido, Morphologie, Morphology, Morfología, Mouillabilité, Wettability, Remojabilidad, Propriété surface, Surface properties, Propiedad superficie, Pulvérisation haute fréquence, Radiofrequency sputtering, Pulverización alta frecuencia, Relation mise en oeuvre propriété, Property processing relationship, Relación puesta en marcha propiedad, Relation mise en oeuvre structure, Structure processing relationship, Relación puesta en marcha estructura, Soie, Silk, Seda, Tissu textile, Woven material, Tela textil, Traitement surface, Surface treatment, and Tratamiento superficie

This paper describes the surface functionalization of woven silk fabric by magnetron sputter coating of PTFE (polytetrafluoroethylene). The PTFE sputter coating was applied to improve the hydrophobic property of silk fabric. The effects of PTFE sputter coating on surface morphology and surface chemical properties were characterized using atomic force microscopy (AFM) and ATR- FTIR (attenuated total reflection-Fourier transform infrared spectroscopy). The wettability of the fabric was characterized through measuring the surface contact angle by a dynamic sessile analysis (DSA) technique. The contact angle of the PTFE coated fabric showed a significant increase from 68° to about 138°. The experimental results also revealed that larger sputtering pressures brought less contact angle hysteresis.

Chemical industry parachemical industry, Industrie chimique et parachimique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Technologie des polymères, Technology of polymers, Formes d'application et semiproduits, Forms of application and semi-finished materials, Matériaux composites, Composites, Propriété interface, Interface properties, Propiedad interfase, Amide copolymère, Amide copolymer, Amida copolímero, Caoutchouc thermoplastique, Thermoplastic rubber, Caucho termoplástico, Copolymère séquencé, Block copolymer, Copolímero secuencia, Ether copolymère, Ether copolymer, Eter copolímero, Etude expérimentale, Experimental study, Estudio experimental, Fibre aramide, Aramid fiber, Fibra aramida, Fibre minérale, Mineral fiber, Fibra inorgánica, Fibre synthétique, Synthetic fiber, Fibra sintética, Interface fibre matrice, Matrix fiber interface, Interfase fibra matriz, Matériau composite, Composite material, Material compuesto, Matériau renforcé fibre, Fiber reinforced material, Material reforzado fibra, Mode rupture, Fracture mode, Modo ruptura, Polymère aromatique, Aromatic polymer, Polímero aromático, Propriété mécanique, Mechanical properties, Propiedad mecánica, Propriété traction, Tensile property, Propiedad tracción, Relation mise en oeuvre propriété, Property processing relationship, Relación puesta en marcha propiedad, Résistance cisaillement, Shear strength, Resistencia cizallamiento, Spectrométrie Raman, Raman spectrometry, Espectrometría Raman, Traitement chimique, Chemical treatment, Tratamiento químico, Traitement par plasma, Plasma assisted processing, Traitement surface, Surface treatment, Tratamiento superficie, Longueur fibre, Twaron, Téréphtalamide p phénylène polymère, and Téréphtalamide(p-phénylène) polymère

The interfacial micromechanics of Twaron 2200 aramid fibers in an engineering thermoplastic elastomer (Pebax 7033, polyether amide block co-polymer) has been investigated by determining the distribution of interfacial shear stress along fibers in single-fiber model composites using Raman spectroscopy. The effects of various fiber surface treatments on the interfacial shear stress and fragmentation of the aramid fibers are discussed. The fiber average stress increased linearly with applied matrix stress up to first fracture. Each composite was subjected to incremental tensile loading up to full fragmentation, while the stress in the fiber was monitored at each level of the applied stress. It was shown that the experimental approach allowed us to discriminate between the strengths of the interfaces in the different surface-treated aramid fiber Pebax matrix systems, but also to detect different phenomena (interfacial debonding, matrix yielding and fiber fracture) related intimately to the nature of stress transfer in composite materials. The efficacy of the surface treatments was clear by comparing the maximum interfacial shear stress with the fragment lengths of the modified aramid fibers. The fiber breaks observed using Raman spectroscopy were not clean breaks as observed with carbon or glass fibers, but manifested themselves as apparent breaks by fiber skin failure. The regions of fiber fracture were also investigated using optical microscopy.

Chemical industry parachemical industry, Industrie chimique et parachimique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Technologie des polymères, Technology of polymers, Formes d'application et semiproduits, Forms of application and semi-finished materials, Matériaux composites, Composites, Composite hybride, Hybrid composite, Compuesto híbrido, Ensimage, Textile oiling, Aceitado, Etude expérimentale, Experimental study, Estudio experimental, Fibre minérale, Mineral fiber, Fibra inorgánica, Fibre synthétique, Synthetic fiber, Fibra sintética, Fibre verre, Glass fiber, Fibra vidrio, Filage état liquide, Melt spinning, Hilado estado líquido, Matériau composite, Composite material, Material compuesto, Matériau renforcé dispersion, Dispersion reinforced material, Material renforzado dispersión, Matériau renforcé fibre, Fiber reinforced material, Material reforzado fibra, Morphologie, Morphology, Morfología, Nanotube carbone, Carbon nanotubes, Nanotube monofeuillet, Singlewalled nanotube, Nanotubo pared única, Oléfine polymère, Olefin polymer, Olefina polímero, Propriété mécanique, Mechanical properties, Propiedad mecánica, Propène polymère, Propylene polymer, Propeno polímero, Relation mise en oeuvre propriété, Property processing relationship, Relación puesta en marcha propiedad, Résistance cisaillement, Shear strength, Resistencia cizallamiento, Résistance compression, Compressive strength, Resistencia compresión, Résistance traction, Tensile strength, Resistencia tracción, Traitement surface, Surface treatment, and Tratamiento superficie

Developing commingled yam technologies and understanding the fundamental interface nanostructures of reinforcement and thermoplastic filaments are of significant current interest. Previous research on commingled yarns was mainly focused on the air-jet texturing process, while the mechanical properties of the composites are strongly influenced by the impregnation homogeneity, the polymer sizing properties and consolidation process. Here, we report a unique melt spinning equipment for E-glass fiber which is compatibly combined with a melt spinning extruder to manufacture commingled yarns. The in-situ commingling enables to combine homogeneously both glass and polypropylene filament arrays in one processing step and without fiber damage compared to commingling by air texturing. Variation of processing conditions are investigated, i.e. sizings, diameter ratios, and arrangements of sizing/finish application related to intermingling of filament arrays. A rapid processing is achieved because of good intermingling and the low flow paths. We found that the sizing enables a good strand integrity with the polypropylene yarn. The interfacial adhesion can be improved with a sizing for glass fibers consisting of aminosilane and maleic anhydride grafted polypropylene film former, which results in both improved transverse tensile strength and compression shear strength. We also found that a very small amount of single-wall carbon nanotubes (SWNTs) in the sizing provides significantly improved interfacial adhesion strength. This is attributed to the change in fracture behavior of the nano-structured interface and morphology of the model single-fiber composites.

Chemical industry parachemical industry, Industrie chimique et parachimique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Technologie des polymères, Technology of polymers, Formes d'application et semiproduits, Forms of application and semi-finished materials, Stratifiés, Laminates, Adhésivité, Adhesivity, Adhesividad, Benzooxazole dérivé polymère, Benzoxazole derivative polymer, Benzooxazol derivado polímero, Epoxyde résine, Epoxy resin, Epóxido resina, Etude expérimentale, Experimental study, Estudio experimental, Fibre synthétique, Synthetic fiber, Fibra sintética, Matériau composite, Composite material, Material compuesto, Matériau renforcé fibre, Fiber reinforced material, Material reforzado fibra, Polymère aromatique, Aromatic polymer, Polímero aromático, Propriété interface, Interface properties, Propiedad interfase, Propriété mécanique, Mechanical properties, Propiedad mecánica, Relation mise en oeuvre propriété, Property processing relationship, Relación puesta en marcha propiedad, Résistance cisaillement, Shear strength, Resistencia cizallamiento, Résistance traction, Tensile strength, Resistencia tracción, Stratifié, Laminate, Estratificado, Traitement chimique, Chemical treatment, Tratamiento químico, Traitement par plasma, Plasma assisted processing, Traitement surface, Surface treatment, Tratamiento superficie, Benzobisoxazole(p-phénylène) polymère, and Résistance cisaillement interlaminaire

A composite of poly p-phenylene-2,6-benzobisoxazole (PBO) fiber and epoxy resin has excellent electrical insulation properties. However, it is a challenging issue to improve its mechanical properties because of poor adhesion between PBO fiber and matrix. The relatively smooth and chemically inactive surface of PBO fiber prevent efficient chemical bonding in the composite interface. Here, we report the surface modification of PBO fibers by UV irradiation, O2 and NH3 plasma, as well as acidic treatments. We found that the surface free energy and roughness are increased for both sized and extracted fibers after plasma treatments together with maleic anhydride grafting. The sized fiber shows marginal improvement in adhesion strength and no change in fiber tensile strength because of the barrier effect of the finish. For the extracted fiber, however, the tensile strength of the fiber is sensitive to surface treatment conditions and considerable strength reduction occurred, particularly for cases of acidic treatments and UV irradiation. This is because that the treatments increase the surface roughness and introduce more surface flaws. The extracted fiber surface has no adequate wetting and functional groups, which in turn results in coarse interface structures and causes reduction or no apparent variation of the adhesion strength. The fracture surfaces after single fiber pull-out tests exhibit adhesive interfacial failure along the fiber surface, which is further confirmed by similar adhesion strength and interlaminar shear strength values when the fiber was embedded in various epoxy resins with different temperature behavior.

Chemical industry parachemical industry, Industrie chimique et parachimique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, 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), Propriétés physiques non électroniques de couches minces, Physical properties of thin films, nonelectronic, Propriétés mécaniques et acoustiques, Mechanical and acoustical properties, Adhérence, Adhesion, Carbure fritté, Cemented carbides, Carburo sinterizado, Cermet, Cermets, Cobalt, Etude expérimentale, Experimental study, Indentation, Matériau revêtement, Coating material, Material revestimiento, Microscopie électronique balayage, Scanning electron microscopy, Métal dur, Hard metals, Propriété mécanique, Mechanical properties, Titane nitrure, Titanium nitrides, Traitement surface, Surface treatments, Tungstène carbure, Tungsten carbides, Usinage électroérosion, Electrical discharge machining, Cermet WC Co, N Ti, and TiN

Electrical discharge machining (EDM) is an alternative-shaping route for manufacturing complex component shapes of hard and brittle materials such as hardmetals (WC-Co cemented carbides). It is well established that in these materials EDM typically induces a heat affected surface layer with poor integrity. This degradation effect may be compensated through specific post-EDM surface treatments either by thermomechanical means or material surface deposition. In the latter case, a key property for optimal performance is the level of coating to substrate adhesion and how this is affected by the EDM-induced surface. The main objective of this investigation was to evaluate the adhesion strength of TiN coatings on EDMed hardmetals. A series of hardmetal samples that had been subjected to different multi-pass sequential EDM levels were coated with TiN. Adhesion behavior was assessed using the indentation adhesion test and comparing the critical load for crack extension (Pc) and the interfacial fracture toughness (KIc,interface) to those exhibited by the TiN coating deposited on a ground and polished substrate (used as baseline control). Experimental results indicated that indentation adhesion increased with finer-executed EDM, almost reaching baseline level values. The results are discussed on the basis of the compromising EDM influence on both surface integrity of the substrate and tortuousness at the interface, the latter resulting in mechanical anchoring of the TiN coating to the hardmetal substrate.

Chemical industry parachemical industry, Industrie chimique et parachimique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, 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, Nanomatériaux et nanostructures : fabrication et caractèrisation, Nanoscale materials and structures: fabrication and characterization, Nanostructures hybrides minéral-organique, Organic-inorganic hybrid nanostructures, Méthodes de nanofabrication, Methods of nanofabrication, Méthodes de synthèse chimique, Chemical synthesis methods, Composé minéral, Inorganic compounds, Composé organique, Organic compounds, Oxyde, Oxides, Diffraction RX, XRD, Effet température, Temperature effects, Etat supercritique, Supercritical state, Etude expérimentale, Experimental study, In situ, Matériau hybride, Hybrid material, Material híbrido, Microscopie électronique transmission, Transmission electron microscopy, Métal Oxyde, Metals Oxides, Méthode en solution, Growth from solution, Método en solución, Nanoparticule, Nanoparticles, Préparation chimique, Chemical preparation, Spectrométrie FTIR, Fourier-transformed infrared spectrometry, Espectrometría FTIR, Synthèse hydrothermale, Hydrothermal synthesis, Traitement surface, and Surface treatments

We have developed supercritical hydrothermal synthesis method of metal oxide nanoparticles where metal salt aqueous solution is mixed with high temperature water to rapidly increase the temperature of the metal salt solution and thus reduce the reactions and crystallizations during the heating up period. By using this method, we succeeded in the continuous and rapid production of metal oxide nanocrystals. A new method proposes to synthesize organic-inorganic fused materials based on the methods of supercritical hydrothermal synthesis. By introducing organic materials in a reaction atmosphere of supercritical hydrothermal synthesis, we successfully synthesized metal oxide nanoparticles whose surface was modified with organic materials. In supercritical state, water and organic materials form a homogeneous phase, which provides an excellent reaction atmosphere for the organic modification of nanoparticles. Modification with bio-materials including amino acids was also possible. By changing organic modifiers, particle morphology and crystal structure were changed. This organic surface modification provides a various unique characteristics for the nanoparticles: Dispersion of nanoparticles in aqueous solutions, organic solvents or in liquid polymers can be controlled by selecting hydrophilic or hydrophobic modifiers.

Chemical industry parachemical industry, Industrie chimique et parachimique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Technologie des polymères, Technology of polymers, Formes d'application et semiproduits, Forms of application and semi-finished materials, Matériaux composites, Composites, Alvéolaire, Foam(plastics), Alveolar, Bismaléimide résine, Bismaleimide resin, Bismaleimida resina, Etude expérimentale, Experimental study, Estudio experimental, Matériau composite, Composite material, Material compuesto, Matériau renforcé dispersion, Dispersion reinforced material, Material renforzado dispersión, Microballon, Microballoon, Microbalón, Microscopie électronique balayage, Scanning electron microscopy, Microscopía electrónica barrido, Mode rupture, Fracture mode, Modo ruptura, Mousse syntactique, Syntactic foam, Espuma sintáctica, Méthode étude, Investigation method, Método estudio, Propriété mécanique, Mechanical properties, Propiedad mecánica, Résistance compression, Compressive strength, Resistencia compresión, Résistance flexion, Bending strength, Resistencia flexión, Traitement surface, Surface treatment, Tratamiento superficie, Verre, Glass, and Vidrio

Samples of syntactic foam containing hollow glass microspheres of 0.108 and 0.253 g/cm3 tap densities, some with a silane surface treatment, were subjected to different stress states and examined for failure modes. All foams contained the same volume fraction of APO-BMI, a bismaleimide resin binder. The samples were tested in compression and in three-point bend, and mechanical properties were compared between the various foams. Microsphere strength had a strong effect on overall uniaxial compressive strength with interface strength playing a secondary, yet significant role. In three-point bending, the role of the interface was much more critical. Cross sections of the compression test samples were examined by optical microscopy, and fracture surfaces were investigated by scanning electron microscopy.

Chemical industry parachemical industry, Industrie chimique et parachimique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, 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), Surfaces solides et interfaces solide-solide, Solid surfaces and solid-solid interfaces, Structure et topographie de surface, Surface structure and topography, 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, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Radiotherapie. Traitement instrumental. Physiotherapie. Reeducation. Readaptation, orthophonie, crenotherapie. Traitement dietetique et traitements divers (generalites), Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects), Technologie. Biomatériaux. Equipements. Matériel. Appareillage, Technology. Biomaterials. Equipments. Material. Instrumentation, Oxidation, Métal transition, Transition elements, Anodisation, Anodizing, Application dentaire, Dental application, Aplicación dental, Zahnmedizinische Anwendung, Biomatériau, Biomedical materials, Dégazage, Outgassing, Etude expérimentale, Experimental study, Haute résolution, High-resolution methods, Interface solide solide, Solid-solid interfaces, Microscopie électronique balayage, Scanning electron microscopy, Microscopie électronique transmission, Transmission electron microscopy, Oxydation, Oxidation, Structure interface, Interface structure, Titane oxyde, Titanium oxides, Titane, Titanium, Traitement surface, Surface treatments, O Ti, Ti, and TiO2

High-resolution electron microscopy was used to investigate two types of titanium-oxide interface structures. The first type was generated by thermal oxidation during the degassing process, which is one step in the process of porcelain-fused-to-metal systems. The thermal oxidation was performed for 1 min at a temperature of 1073 K in a porcelain furnace under a reduced pressure at 27 hPa. Columnar and granular rutile oxide formed on the titanium, and the surface oxide layer was almost 1 μm thick. On an atomic scale, the crystal size of the rutile adjacent to the interface decreased about 10 nm. In addition, a very thin transitional layer 2-3 nm thick formed at the titanium-oxide interface. The crystal structure of the thin layer seemed to be the TiO phase with a NaCl-type structure. The interface between the hcp titanium and TiO phases was coherent through the close-packed planes ((0 0 0 2)hcp and (1 1 1)TiO). Partial coherency was observed at the interface between the TiO and TiO2 phases. The second type of titanium-oxide interface was generated by anodization on a screw-type titanium implant. The morphology of the surface suggested that the titanium implant had been treated by spark anodization. The surface oxide, which was estimated to be about 10 μm thick, was a mixture of the anatase-type TiO2 phase and the amorphous phase. The crystal size of the anatase varied from less than 10 nm to more than 100 nm. A phosphate anion was concentrated in the amorphous phase. Between the surface oxide and the titanium base, macroscopic defects like cracks and voids were observed. Microscopic observation could not confirm the formation of a clear interface and lattice coherency between the titanium and oxide as a result of the degassing process.

Chemical industry parachemical industry, Industrie chimique et parachimique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, 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, Energie, Energy, Energie naturelle, Natural energy, Energie solaire, Solar energy, Conversion photovoltaïque, Photovoltaic conversion, Cellules solaires. Cellules photoélectrochimiques, Solar cells. Photoelectrochemical cells, Surface cleaning, etching, patterning, Photoelectric conversion: solar cells and arrays, Attaque chimique, Chemical etching, Ataque químico, Cellule solaire silicium, Silicon solar cells, Etude expérimentale, Experimental study, Estudio experimental, Matériau poreux, Porous material, Material poroso, Microscopie électronique balayage, Scanning electron microscopy, Microscopía electrónica barrido, Microstructure, Microestructura, Procédé voie humide, Wet process, Procedimiento vía húmeda, Propriété optique, Optical properties, Propiedad óptica, Propriété photoélectronique, Photoelectronic properties, Propiedad fotoelectrónica, Semiconducteur, Semiconductor materials, Semiconductor(material), Silicium, Silicon, Silicio, Texture, Textura, Traitement surface, Surface treatment, Tratamiento superficie, and mc-Si

Two kinds of surface texturization of mc-Si obtained by wet chemical etching are investigated in view of implementation in the solar cell processing. The first one was the acid texturization of saw damage on the surface of multicrystalline silicon (mc-Si). The second one was macro-porous texturization prepared by double-step chemical etching after KOH saw damage layer was previously removed. Both methods of texturization are realized by chemical etching in HF-HNO3-H2O with different additives. Macro-porous texturization allows to obtain effective reflectivity (Reff) in the range 9-20% from bare mc-Si. This Reffvalue depends on the time of second step etching that causes porous structure modification. The internal quantum efficiency (IQE) of cells with this kind of texturization has possibility to reach better conversion efficiency than the standard mc-Si solar cells. However, low shunt resistance depends on morphology of porous layer and it is the main factor which can reduce open circuit voltage and conversion efficiency of cells. The effective reflectivity is about 17% for acid texturized mc-Si wafer. The investigation of surface morphology by scanning electron microscopy (SEM) revealed that the dislocations are appearing during chemical etching and they can reduce open circuit voltage. The density of the dislocations can be reduced by controlling depth of etching and optimisation of acid solution.

Chemical industry parachemical industry, Industrie chimique et parachimique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Energie, Energy, Energie naturelle, Natural energy, Energie solaire, Solar energy, Conversion photovoltaïque, Photovoltaic conversion, Cellules solaires. Cellules photoélectrochimiques, Solar cells. Photoelectrochemical cells, Photoelectric conversion: solar cells and arrays, Amélioration, Improvement, Mejora, Attaque chimique, Chemical etching, Ataque químico, Cellule solaire silicium, Silicon solar cells, Etude expérimentale, Experimental study, Estudio experimental, Getter, Performance, Rendimiento, Piégeage impureté, Impurity trapping, Captura impureza, Stratégie, Strategy, Estrategia, Traitement surface, Surface treatment, and Tratamiento superficie

This paper reports the recent performance improvements in crystalline silicon solar cells. These have been achieved by a combination of two mechanisms. One is related to the solar cell design which consists of grooving silicon substrates to obtain a structure suitable to perform an efficient gettering process. The proposed structure consists of buried emitter contacts rear locally diffused. Chemical-vapour etching has been used in the process sequence both to realize buried contacts and opening periodic arrangement of small deep grooving holes, for local aluminum diffusion. The second consists to perform a gettering sequence by Rapid Thermal (RT) heat treatments of p-type silicon in an infrared furnace, in controlled silicon tetrachloride (SiCl4) and N2 gas atmosphere. The resulting silicon shows an increase of minority drift mobility determined by Hall Effect to reach 1417 cm2 V-1s-1, and a decrease in resistivity over 40 μm on both sides of silicon substrates. Moreover, Light Beam Induced Current (LBIC) investigations show an improvement of diffusion bulk lengths (Ln) to ward 210 μm as compared to silicon starting substrates.

Chemical industry parachemical industry, Industrie chimique et parachimique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, 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, Dépôt chimique en phase vapeur (incluant le cvd activé par plasma, mocvd, etc.), Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.), Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Energie, Energy, Energie naturelle, Natural energy, Energie solaire, Solar energy, Conversion photovoltaïque, Photovoltaic conversion, Cellules solaires. Cellules photoélectrochimiques, Solar cells. Photoelectrochemical cells, Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, etc.), Passivation, Photoelectric conversion: solar cells and arrays, Addition hydrogène, Hydrogen additions, Analyse structurale, Structural analysis, Análisis estructural, Basse température, Low temperature, Baja temperatura, Caractérisation, Characterization, Caracterización, Cellule solaire, Solar cells, Etat amorphe, Amorphous state, Etude expérimentale, Experimental study, Film, Films, Matériau amorphe hydrogéné, Amorphous hydrogenated material, Méthode PECVD, PECVD, Passivation, Propriété électrique, Electrical properties, Préparation chimique, Chemical preparation, Silicium Nitrure, Silicon Nitrides, Spectre IR, Infrared spectra, Traitement surface, Surface treatments, N Si, and a-SixNy:H

Deposition conditions and some structural and electrical properties of amorphous silicon nitride (SixNy:H) films deposited on Si substrates have been studied for photovoltaic applications. A plasma enhanced chemical vapor deposition (PECVD) system has been used for the study. Experiments have been performed varying the flow ratios and dilution of the reactant gases. Increased hydrogen (H2) dilution leads to reduced deposition rate and a better controllability in the growth process. The hydrogen content in the film also decreases with increasing H2 dilution of the reactant gases. Flow ratio of the reactant gases (SiH4/NH3) also influences the growth rate. There is an optimal reactant gas mix to maximize the film growth rate. However, the film stoichiometry is also modified by changing the gas mix, with higher flow ratios resulting in Si-rich films. The level of interracial recombination of minority carriers has been studied by capacitance-voltage and effective lifetime measurements. Bombardment by the energetic species in the plasma leads to plasma damage at the interface. These interfacial defects can be annealed by a post-deposition, low temperature treatment.

Chemical industry parachemical industry, Industrie chimique et parachimique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, 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, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Propriétés optiques, spectroscopie et autres interactions de la matière condensée avec les particules et le rayonnement, Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation, Propriétés optiques des couches minces, Optical properties of specific thin films, Semiconducteurs élémentaires et isolants, Elemental semiconductors and insulators, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Surface cleaning, etching, patterning, Non métal, Nonmetals, Analyse structurale, Structural analysis, Análisis estructural, Attaque chimique, Chemical etching, Ataque químico, Couche ultramince, Ultrathin films, Etude expérimentale, Experimental study, Matériau poreux, Porous materials, Microscopie force atomique, Atomic force microscopy, Microscopie tunnel balayage, Scanning tunneling microscopy, Morphologie, Morphology, Photoluminescence, Propriété optique, Optical properties, Semiconducteur, Semiconductor materials, Silicium, Silicon, Traitement surface, Surface treatments, Multi-Si, Por-Si, and Si

Ultrathin porous silicon layers have been stain-etched upon multicrystalline silicon (multi-Si) substrates. We studied optical and structural properties of porous silicon by photoluminescence, photo-luminescence excitation, reflection, atomic force microscopy and scanning tunnel microscopy methods. It was observed that the thickness of porous silicon did not exceed 20 nm. The photoluminescence method has shown that photoluminescence spectra of porous silicon of different grains have shown that they differ insignificantly (∼10%) in intensity. It was found that por-Si layers with optimal antireflection characteristics was obtained during etching time 7 min. In the paper the comparison of the reflection characteristics of investigated samples por-Si with industrial antireflection coating is presented.

Chemical industry parachemical industry, Industrie chimique et parachimique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, 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, Autres méthodes de préparation et de traitement des matériaux, Materials synthesis; materials processing, Sciences appliquees, Applied sciences, Industries chimique et parachimique, Chemical industry and chemicals, Matériaux de construction. Céramique. Verres, Building materials. Ceramics. Glasses, Industries céramiques, Ceramic industries, Céramiques techniques, Technical ceramics, Divers, Miscellaneous, Metaux. Metallurgie, Metals. Metallurgy, Joining; welding, Alumine, Alumina, Alúmina, Tonerde, Aluminium, Aluminio, Assemblage, Joining, Ensamble, Verbinden, Contact céramique métal, Ceramic metal contact, Contacto ceramica metal, Couche mince, Thin film, Capa fina, Duennschicht, Céramique oxyde, Oxide ceramics, Cerámica óxido, Oxidkeramik, Céramique technique, Technical ceramics, Cerámica técnica, Etude expérimentale, Experimental study, Estudio experimental, Experimentelle Untersuchung, Fracture, Fractura, Interface solide solide, Solid solid interface, Interfase sólido sólido, Grenzschicht fest fest, Liaison matériau, Bonding, Microscopie électronique balayage, Scanning electron microscopy, Microscopía electrónica barrido, Rasterelektronenmikroskopie, Microscopie électronique transmission, Transmission electron microscopy, Microscopía electrónica transmisión, Transmissionselektronenmikroskopie, Phase liquide, Liquid phase, Fase líquida, Fluessige Phase, Propriété interface, Interface properties, Propiedad interfase, Propriété mécanique, Mechanical properties, Propiedad mecánica, Résistance flexion, Bending strength, Resistencia flexión, Biegefestigkeit, Résistance mécanique, Strength, Resistencia mecánica, Festigkeit, Titane, Titanium, Titanio, Titan, Traitement surface, Surface treatment, Tratamiento superficie, and Oberflaechenbehandlung

The subject of the work was to study the effect of Ti thin film on alumina ceramic on mechanical strength and fracture character of Al2O3/Al/Al2O3 joints. The joints were formed by liquid state bonding of alumina substrates covered with titanium thin film of 800 nm thickness using Al interlayer of 30 μm thickness at temperature of 973 K in a vacuum of 0.2 mPa for 5 min. The bend strength was measured by four-point bending test at room temperature. Scanning and transmission electron microscopy were applied for detailed characterization of interface structure and failure character of fractured joint surfaces. Result analysis has shown that application of the Ti thin film on alumina leads to decrease of bond strength properties of Al2O3/Al/Al2O3 joints along with the change either of structure and chemistry of interface or of failure character.

Chemical industry parachemical industry, Industrie chimique et parachimique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Technologie des polymères, Technology of polymers, Appareillage et mise en oeuvre, Machinery and processing, Matières plastiques, Plastics, Revêtement, métallisation, coloration, Coating, metallization, dyeing, Etude comparative, Comparative study, Estudio comparativo, Etude expérimentale, Experimental study, Estudio experimental, Microscopie force atomique, Atomic force microscopy, Microscopía fuerza atómica, Microscopie force latérale, Lateral force microscopy, Microscopia fuerza lateral, Microscopie électronique balayage, Scanning electron microscopy, Microscopía electrónica barrido, Morphologie, Morphology, Morfología, Méthode étude, Investigation method, Método estudio, Oléfine polymère, Olefin polymer, Olefina polímero, Propène polymère, Propylene polymer, Propeno polímero, Relation mise en oeuvre structure, Structure processing relationship, Relación puesta en marcha estructura, Ruban, Tape, Cinta, Traitement par plasma, Plasma assisted processing, Traitement surface, Surface treatment, and Tratamiento superficie

This paper highlights the applications of Scanning Probe Microscopy (SPM) and Scanning Electron Microscopy (SEM) to study the effects of argon, nitrogen and oxygen plasma treatments on the topography of polypropylene (PP) tapes. Contrasting surface effects created by the different plasma gases as observed by Atomic Force Microscopy (AFM), Lateral Force Microscopy (LFM) and SEM are discussed in detail with images obtained from both AFM and SEM demonstrating the changes in the surface topography.

Chemical industry parachemical industry, Industrie chimique et parachimique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Technologie des polymères, Technology of polymers, Formes d'application et semiproduits, Forms of application and semi-finished materials, Matériaux composites, Composites, Acrylique acide copolymère, Acrylic acid copolymer, Acrílico ácido copolímero, Argent, Silver, Plata, Copolymère greffé, Graft copolymer, Copolímero injertado, Dépôt plasma, Plasma deposition, Depósito plasma, Etude expérimentale, Experimental study, Estudio experimental, Fibre synthétique, Synthetic fiber, Fibra sintética, Greffage, Grafting, Injerto, Morphologie, Morphology, Morfología, Mouillabilité, Wettability, Remojabilidad, Méthode PECVD, PECVD, Nanostructure, Nanoestructura, Oléfine copolymère, Olefin copolymer, Olefina copolímero, Oléfine polymère, Olefin polymer, Olefina polímero, Oxydation, Oxidation, Oxidación, Propriété surface, Surface properties, Propiedad superficie, Propène copolymère, Propylene copolymer, Propeno copolímero, Propène polymère, Propylene polymer, Propeno polímero, Relation mise en oeuvre propriété, Property processing relationship, Relación puesta en marcha propiedad, Relation mise en oeuvre structure, Structure processing relationship, Relación puesta en marcha estructura, Traitement par plasma, Plasma assisted processing, Traitement surface, Surface treatment, and Tratamiento superficie

Polypropylene (PP) fibres have an extensive range of applications, including filtration, composites, biomaterials and electronics. In these applications, the surface properties of the fibres are particularly important. This paper presents examples of the use of gas plasma technology to create functional nanostructures on PP fibre surfaces, which render the surfaces hydrophilic. It is also shown how these treatments can be regulated to produce the desired level of hydrophilicity for a given application. Three principal modifications have been performed, to create functional nanostructures: plasma activation with oxygen gas plasma, grafting of polyacrylic acid following argon gas plasma treatment, and plasma-enhanced deposition of silver. Atomic force microscopy (AFM) and environmental scanning electron microscopy (ESEM) were employed to characterise the morphology, surface structure and composition of the fibres treated by gas plasma.