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Inorganic chemistry, Chimie minérale, Crystallography, Cristallographie cristallogenèse, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Electrodes: préparations et propriétés, Electrodes: preparations and properties, Batterie lithium, Lithium battery, Cathode, Cátodo, Couche superficielle, Surface layer, Capa superficial, Diffraction RX, X ray diffraction, Difracción RX, Oxyde, Oxides, Óxido, Spectre photoélectron RX, X-ray photoelectron spectra, Spinelles, Spinels, Espinelas, Traitement surface, Surface treatment, Tratamiento superficie, Transfert charge, Charge transfer, Transferencia carga, Cathode materials, Lithium-ion battery, Spinel-like structure, and Surface modification

Li1.375Ni0.25Mn0.75O2+γ exhibits an obviously enhanced electrochemical performance after AlF3 surface modification, including the high initial discharge capacities of 276.8 mA h g―1 and high coulombic efficiency of 93.6%. The results from powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma (ICP) and galvanostatical test confirm that its electrochemical improvement can be mainly attributed to the appearance of spinel-like structure on the surface of the layered material induced by AlF3-modified. Moreover, the reduced charge transfer resistance (Rct) during cycling contributes to a better cycle stability of AIF3-modified Li1.375Ni0.25Mn0.75O2+γ.

Inorganic chemistry, Chimie minérale, Crystallography, Cristallographie cristallogenèse, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, 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, Apatite hydroxylée, Hydroxyapatite, Hidroxiapatito, Biocompatibilité, Biocompatibility, Biocompatibilidad, Biomatériau, Biomaterial, Essai rayage, Scratching test, Ensayo al rayado, Frittage, Sintering, Sinterización, Haute température, High temperature, Alta temperatura, Implant, Implante, Magnésium alliage, Magnesium alloy, Magnesio aleación, Oxydation, Oxidation, Oxidación, Propriété électrochimique, Electrochemical properties, Propiedad electroquímica, Revêtement composite, Composite coating, Revestimiento compuesto, Résistance corrosion, Corrosion resistance, Resistencia corrosión, Traitement surface, Surface treatment, Tratamiento superficie, Vitesse corrosion, Corrosion rate, Velocidad corrosión, Anodisation par plasma, Plasma electrolytic oxidation, Bio-composite coating, Biodegradability, Bonding strength, and Micro-arc oxidation

Magnesium alloys have been used as biodegradable implants in load bearing applications due to their biodegradability and excellent mechanical properties. However, the rapid corrosion rate still needs to be improved by surface modification, and so does the biocompatibility according to clinical demands for bone implants. This study demonstrated the effectiveness of applying a bio-composite coating on magnesium alloy by adding HA particles in electrolyte during MAO process (MAO-HA). The results suggested that HA particles took part in MAO process, getting decomposed into Ca3(PO4)2 under a high temperature caused by the intense micro-arc discharge generated at high applied voltage. In the meantime, synthesis of Mg3(PO4)2 was promoted under the high temperature. The sintering-caused phases Ca3(PO4)2 and Mg3(PO4)2 combined with HA composed the bioactive coating. Testified by scratch test, electrochemical test and short-term immersion test, the composite coating showed high bonding strength and improved corrosion resistance owning to the sintering-caused products sealed partial pores of the MAO coating. Therefore, this study indicated that the bio-composite coating obtained by MAO-HA process may be suitable for synthesizing promising bone implant materials in clinical application.

Inorganic chemistry, Chimie minérale, 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 electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Structure électronique et propriétés électriques des surfaces, interfaces, couches minces et structures de basse dimensionnalité, Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures, Transport électronique dans les multicouches, nanomatériaux et nanostructures, Electronic transport in multilayers, nanoscale materials and structures, Sciences appliquees, Applied sciences, Electrotechnique. Electroenergetique, Electrical engineering. Electrical power engineering, Matériel électrique divers, Various equipment and components, Condensateurs. Résistances. Filtres, Capacitors. Resistors. Filters, Capacité électrique, Capacitance, Capacitancia, Condensateur, Capacitor, Condensador, Couche autoassemblée, Self-assembled layer, Capa autoensamblada, Nanotube, Nanotubo, Oxyde de titane, Titanium oxide, Titanio óxido, Propriété surface, Surface properties, Propiedad superficie, Propriété électrochimique, Electrochemical properties, Propiedad electroquímica, Réseau (arrangement), Array, Red, Traitement surface, Surface treatment, Tratamiento superficie, TiO2, Supercapacitors, Surface engineering, and Titania nanotubes

Here, we present a facile route to establish and control a net negative charge on the surface of TiO2 nanotube as an enabling platform to achieve extraordinary capacitive behavior compared to conventional electric double layer capacitors. The engineering of the surface electrical properties of TiO2 nanotube resulted in an overall improvement in electrochemical performance which is beneficial in a range of applications including wearable light weight electronic devices and energy storage applications. The maximum aerial capacitance of 1.6 mF cm-2 obtained here along with good capacitance retention of 97% after 1000 cycles demonstrate promising properties of these structures for applications in energy storage area.

Inorganic chemistry, Chimie minérale, Crystallography, Cristallographie cristallogenèse, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Acier, Steel, Acero, Angle contact, Contact angle, Angulo contacto, Kontaktwinkel, Attaque chimique, Chemical etching, Ataque químico, Chemisches Aetzen, Bionique, Bionics, Biónica, Morphologie surface, Surface morphology, Mouillabilité, Wettability, Remojabilidad, Benetzbarkeit, Rugosité, Roughness, Rugosidad, Rauhigkeit, Sablage, Sand blasting, Enarenación, Texture, Textura, Textur, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Fluorination treatment, Pipeline steel, Sandblasting roughening treatment, and Superhydrophobic surface

A superhydrophobic surface with the bionic microtexture was prepared successfully on X52 pipeline steel using the sandblasting roughening treatment, chemical etching and fluorination treatment composite methods. The pipeline steel surface was modified with (heptadecalfuoro-1,1,2,2-tetradecyl)trimethoxysilane (HFTTMS). The effects of HCl concentration and the chemical etching time on the morphology of the pipeline steel surface and the wettability of the surface with distilled water were investigated. The results show that at certain HCl concentration, with the increase of the chemical etching time, the contact angles have a maximum value. At certain chemical etching time, the higher HCl concentration was, the severer the reaction between the pipeline steel surface and HCl solution was, and the surface roughness formed by the sandblasting roughening treatment decreased rapidly, resulting in the decrease of the contact angle. The sample sandblasted for 1.5 min and etched chemically for 1.5 h at 7 mol/L HCl can obtain the best surface fine structure. After the fluorination treatment, the biggest contact angle is 156.4°.

Inorganic chemistry, Chimie minérale, 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 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, Autres méthodes de préparation et de traitement des matériaux, Materials synthesis; materials processing, Baryum Strontium Titanate Mixte, Barium Strontium Titanates Mixed, Mixto, Constante diélectrique, Permittivity, Coprécipitation, Coprecipitation, Diffraction RX, XRD, Matériau composite, Composite materials, Microscopie électronique balayage, Scanning electron microscopy, Microstructure, Perovskites, Poudre fine, Fine powder, Polvo fino, Propriété thermique, Thermal properties, Stabilité thermique, Thermal stability, Styrène polymère, Polystyrene, Traitement surface, Surface treatments, Ba0.5Sr0.5TiO3, Dielectric properties, and Surface modification

Pure perovskite phase Ba0.5Sr0.5TiO3 powders were synthesized by facile co-precipitation using inexpensive TiOSO4 as the raw material. The post-calcining treatment was at the low temperature of 950 °C, which was about 200 °C lower than that of the conventional solid-state method. The effects of two types of precipitation agents on the properties of Ba0.5Sr0.5TiO3 powders were investigated, and cubic Ba0.5Sr0.5TiO3 particles were obtained at the optimal conditions. Afterwards, the obtained Ba0.5Sr0.5TiO3 — ceramics were ground into fine ceramic powders, and modified with oleic acid to improve the compatibility with the polystyrene (PS) matrix. The modified ceramic powders were dispersed in PS via solution co-blending to obtain Ba0.5Sr0.5TiO3/PS composites. The structure and morphology of the Ba0.5Sr0.5TiO3/PS composites were characterized through X-ray diffraction (XRD), and scanning electron microscopy (SEM). The SEM images showed that the modified ceramic powders had good dispersion in the PS resin. Moreover, the dielectric and thermal properties of the Ba0.5Sr0.5TiO3/PS composites were investigated, and the results showed that the modified ceramic powders could enhance the dielectric constants and thermal stability of ceramic-polymer composites.

Inorganic chemistry, Chimie minérale, Crystallography, Cristallographie cristallogenèse, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, 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, Elasticité. Plasticité, Elasticity. Plasticity, Dioxyde de carbone, Carbon dioxide, Carbono dióxido, Kohlendioxid, Etat fondu, Molten state, Estado fundido, Microdureté, Microhardness, Microdureza, Mikrohaerte, Microstructure, Microestructura, Mikrogefuege, Module élasticité, Elastic modulus, Módulo elasticidad, Elastizitaetsmodul, Nanoindentation, Nanoindentacion, Phase bêta, Beta phase, Fase beta, Beta Phase, Phase métastable, Metastable phase, Fase metastable, Metastabile Phase, Renforcement mécanique, Strengthening, Refuerzo mecánico, Rhénium alliage, Rhenium alloy, Renio aleación, Rheniumlegierung, Réseau hexagonal, Hexagonal lattices, Titane alliage, Titanium alloy, Titanio aleación, Titanlegierung, Traitement par laser, Laser assisted processing, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Transformation phase, Phase transformation, Transformación fase, Phasenumwandlung, Zirconium alliage, Zirconium alloy, Zirconio aleación, Zirconiumlegierung, Refusion laser, Laser remelting, Laser surface remelting, Mechanical properties, and Ti―Zr alloy

The effects of laser surface remelting (LSR) on the microstructural evolution and surface mechanical properties of Ti―Zr beta titanium alloy were investigated. The surfaces of the Ti―Zr alloy was re-melted using a CO2 laser. X-ray diffraction, Scanning electron microscope, Transmission electron microscope, nanoindentation, and microhardness analyses were performed to evaluate the microstructural and mechanical properties of the alloy. The results showed that the alloy microstructure in the remelting region was greatly refined and homogeneous compared with that in the base material because of the rapid remelting and resolidifying. Meanwhile, the metastable hexagonal ω phases with the size of 20-50 nm was found and uniformly distributed throughout the β matrix after LSR. Phase transformation and microstructural refinement were the major microstructural changes in the alloys after LSR. The microhardness and elastic modulus in the remelted region clearly increased by 92.9% and 21.78%, respectively, compared with those in the region without laser processing. The strengthening effect of LSR on the mechanical properties of the Ti―Zr alloy was also addressed. Our results indicated that LSR was an effective method of improving the surface mechanical properties of alloys.

Inorganic chemistry, Chimie minérale, 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), Structures de basse dimensionnalité (superréseaux, puits quantiques, multicouches): structure et propriétés non électroniques, Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Carbure de bore, Boron carbide, Boro carburo, Changement morphologique, Morphological changes, Contrainte résiduelle, Residual stresses, Diffraction RX, XRD, Indentation, Microdureté, Microhardness, Microscopie électronique balayage, Scanning electron microscopy, Spectrométrie dispersive, Dispersive spectrometry, Espectrometría dispersiva, Tenacité, Fracture toughness, Traitement par laser, Laser assisted processing, Traitement surface, Surface treatments, B4C, B4C tile, Laser treatment, and Residual stress

Laser treatment of B4C tile surfaces is carried out under high pressure nitrogen assisting gas environment. Morphological and metallurgical changes in the laser treated layer are examined by incorporating scanning electron microscope, energy dispersive spectroscopy, and X-ray diffraction. Microhardness and fracture toughness of the laser treated surface are determined from the indentation data. Residual stress formed at the treated surface is obtained by using X-ray diffraction technique, It is found that laser treated surface is free from large scale asperities including cracks and voids; however, some locally scattered shallow cavities with 1.5-2 μm widths are formed at the surface because of high temperature processing. Dense layer, consisting of fine grains, and formation of nitride species (BN and BC2N) enhance microhardness and lower fracture toughness at the surface. Residual stress formed in the treated layer is compressive and the maximum residual stress is in the order of -0.9 GPa.

Inorganic chemistry, Chimie minérale, Crystallography, Cristallographie cristallogenèse, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Corrosion, Protection contre la corrosion, Corrosion prevention, Acier inoxydable, Stainless steel, Acero inoxidable, Nichtrostender Stahl, Alliage amorphe, Amorphous alloy, Aleación amorfa, Amorphe Legierung, Alliage base fer, Iron base alloys, Alliage surface, Surface alloying, Aleación superficie, Oberflaechenlegieren, Matériau composite, Composite material, Material compuesto, Verbundwerkstoff, Modèle thermique, Thermal model, Modelo térmico, Métal transition alliage, Transition metal alloy, Metal transición aleación, Uebergangsmetallegierung, Nanocristal, Nanocrystal, Polarisation anodique, Anodic polarization, Polarización anódica, Anodische Polarisation, Revêtement composite, Composite coating, Revestimiento compuesto, Résistance corrosion, Corrosion resistance, Resistencia corrosión, Korrosionsbestaendigkeit, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Transfert chaleur, Heat transfer, Transferencia térmica, Waermeuebertragung, Vitesse refroidissement, Cooling rate, Velocidad enfriamiento, Abkuehlungsgeschwindigkeit, Coatings, Composite, Laser processing, Metallicglass, and Surface modification

The present study focuses on synthesizing composite coatings for corrosion resistance using laser surface alloying (LSA). Amorphous powder with nominal composition (Fe48Cr15Mo14Y2C15B6) is used as the precursor powder on AISI 4130 steel substrate and processed with a continuous wave ytterbium Nd-YAG fiber laser. A multi-physics based heat transfer model was developed to evaluate the thermal histories experienced during processing. The thermodynamic parameters like peak temperatures and cooling rates are evaluated using the computational model and correlated to the evolution of microstructure. Phase and microstructural characterization of the coatings was conducted using XRD, SEM and TEM. Anodic polarization tests conducted in HCl medium indicated the enhancement in corrosion resistance of the laser processed samples. The laser processed samples showed better corrosion resistance than the substrate and among the processed samples, the corrosion resistance decreased with increasing laser energy density. The reduction in the corrosion resistance can be attributed to the formation of Cr23C6 nano crystals in the amorphous phase. The operating corrosion mechanisms are discussed with the aid of the thermal modeling results.

Inorganic chemistry, Chimie minérale, Crystallography, Cristallographie cristallogenèse, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Electrodes: préparations et propriétés, Electrodes: preparations and properties, Batterie lithium, Lithium battery, Cathode, Cátodo, Cinétique, Kinetics, Cinética, Haute température, High temperature, Alta temperatura, Interphase, Interfase, Microscopie électronique transmission, Transmission electron microscopy, Microscopía electrónica transmisión, Microstructure, Microestructura, Oxyde, Oxides, Óxido, Revêtement surface, Surface coating, Spinelles, Spinels, Espinelas, Stabilité thermique, Thermal stability, Estabilidad térmica, Traitement surface, Surface treatment, Tratamiento superficie, Transfert charge, Charge transfer, Transferencia carga, Verre, Glass, Vidrio, Glass material, High-voltage positive material, Lithium-ion battery, Sucrose-assisted combustion, and Surface modification

A Li2O―2B2O3―glass-coated LiNi0.5Mn1.5O4 (LNMO) cathode active material (GC-LNMO) was synthesized to enhance the thermal stability of LNMO-based electrodes for lithium-ion batteries. The morphologies of the surface-coating layers were analyzed using transmission electron microscopy. The glass coating prevented the surface of the LNMO-based electrode from being directly exposed to the liquid electrolyte solution, preventing Mn at the electrode surface from dissolving into the electrolyte and thus preventing the cell impedance from increasing through the undesirable formation of a cathode―electrolyte-interphase layer and the development of facile charge transfer kinetics during cycling. The electrochemical performance measurements demonstrated that the GC-LNMO-based electrode exhibited remarkably enhanced electrochemical reversibly and stability at elevated temperature (60 °C).

Inorganic chemistry, Chimie minérale, Crystallography, Cristallographie cristallogenèse, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, 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, Fatigue, Acier allié, Alloy steel, Acero aliado, Legierter Stahl, Boronisation, Boronization, Boronización, Broyeur attrition, Attrition mill, Molino atrición, Cinétique, Kinetics, Cinética, Kinetik, Couche superficielle, Surface layer, Capa superficial, Oberflaechenschicht, Energie activation, Activation energy, Energía activación, Aktivierungsenergie, Fatigue thermique, Thermal fatigue, Fatiga térmica, Thermische Ermuedung, Formation nanomotif, Nanopatterning, Formacíon nanomotivo, Grossissement grain, Grain coarsening, Engruesamiento grano, Kornvergroesserung, Orientation préférentielle, Preferred orientation, Orientación preferencial, Bevorzugte Orientierung, Résistance oxydation, Oxidation resistance, Resistencia a la oxidación, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Boronizing kinetics, Diffusion, H13 steel, and Surface mechanical attrition treatment

A nanostructured surface layer was fabricated on AISI H13 steel by means of surface mechanical attrition treatment (SMAT). Boronizing behaviors of the SMAT samples were systematically investigated in comparison with their coarse-grained counterparts. The boron diffusion depth of the SMAT sample with pack boriding treatment at 600 °C for 2 h was about 8 μm, which was much deeper than that of the coarse-grained sample. A much thicker borided layer on the SMAT sample can be synthesized by a duplex boronizing treatment at 600 °C followed by at a higher temperature. The borided layer was composed with monophase of Fe2B and the growth of it exhibited a (002) preferred orientation. Moreover, the activation energy of boron diffusion for the SMAT sample is 140.3 kJ/mol, which is much lower than 209.4 kJ/mol for the coarse-grained counterpart. The results indicate that the boronizing kinetics can be significantly enhanced in the SMAT sample with a duplex boronizing treatment. Furthermore, the thermal fatigue tests show that the borided layer with excellent oxidation resistance and mechanical strength at elevated temperatures could effectively delay the thermal fatigue cracks initiation and impede their propagation. Therefore, the thermal fatigue property of H13 steel with a duplex boronizing treatment can be improved remarkably.

Inorganic chemistry, Chimie minérale, Crystallography, Cristallographie cristallogenèse, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Energie, Energy, Combustibles, Fuels, Combustibles de remplacement. Production et utilisation, Alternative fuels. Production and utilization, Hydrogène, Hydrogen, Diffraction RX, X ray diffraction, Difracción RX, Lanthane alliage, Lanthanum alloy, Lantano aleación, Microscopie électronique balayage, Scanning electron microscopy, Microscopía electrónica barrido, Nickel alliage, Nickel alloy, Níquel aleación, Propriété électrochimique, Electrochemical properties, Propiedad electroquímica, Stockage hydrogène, Hydrogen storage, Traitement chimique, Chemical treatment, Tratamiento químico, Traitement surface, Surface treatment, Tratamiento superficie, LaNi5, Cu2O, CuCl, Electrochemical performance, LaNi5 hydrogen storage alloy, and Surface modification

The LaNi5 hydrogen storage alloy is modified by two steps: firstly, the alloy is treated with an aqueous solution of HF and KF-2H2O, then the as-obtained product reacts with CuCl in aqueous media at 30 °C, 50 °C and 70 °C respectively. XRD and SEM show that the samples obtained at 50 °C and 70 °C contain Cu and Cu2O, and their particles are evenly distributed on the alloy surface. The electrochemical properties of the alloy treated with 12.5 wt.% of the alloy at 50 °C are the best, which discharge 310 mA h g―1 at a current density of 50 mA g―1, and 280 mA h g―1 at 1000 mA g―1, while the pristine alloy discharges only 290 mA h g―1 at a current density of 50 mA g―1, and 180 mA h g―1 at 1000 mA g―1.

Inorganic chemistry, Chimie minérale, 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, Structure des liquides et des solides; cristallographie, Structure of solids and liquids; crystallography, Solides désordonnés, Disordered solids, Verres, Glasses, Effets physiques d'irradiation, défauts d'irradiation, Physical radiation effects, radiation damage, Ions, Ion radiation effects, Alliage base titane, Titanium base alloys, Alliage base zirconium, Zirconium base alloys, Cristallisation, Crystallization, Effet rayonnement, Radiation effects, Fluence, Fluencia, Irradiation ion, Ion irradiation, Irradiación ión, Mouillabilité, Wettability, Métal transition alliage, Transition element alloys, Nanocristal, Nanocrystal, Recuit, Annealing, Résistance corrosion, Corrosion resistance, Structure surface, Surface structure, Structure verre, Glass structure, Traitement surface, Surface treatments, Transition vitreuse, Glass transition, Verre métallique, Metallic glasses, Hardness, Metallic glass, and Nanocrystallization

Surface treatments using multiple Ar ion irradiation processes with a maximum energy and fluence of 200 keV and 1 x 1016 ions/cm2, respectively, have been performed on two different metallic glasses: Zr55Cu28Al10Ni7 and Ti40Zr10Cu38Pd12. Analogous irradiation procedures have been carried out at room temperature (RT) and at T = 620 K (≈0.9 Tg, where Tg denotes the glass transition). The structure, mechanical behavior, wettability and corrosion resistance of the irradiated alloys have been compared with the properties of the as-cast and annealed (T = 620 K) non-irradiated specimens. While ion irradiation at RT does not significantly alter the amorphous structure of the alloys, ion irradiation close to Tg promotes decomposition/nanocrystallization. Consequently, the hardness (H) and reduced Young's modulus (Er) decrease after irradiation at RT but they both increase after irradiation at 620 K. While annealing close to Tg increases the hydrophobicity of the samples, irradiation induces virtually no changes in the contact angle when comparing with the as-cast state. Concerning the corrosion resistance, although not much effect is found after irradiation at RT, an improvement is observed after irradiation at 620 K, particularly for the Ti-based alloy. These results are of practical interest in order to engineer appropriate surface treatments based on ion irradiation, aimed at specific functional applications of bulk metallic glasses.

Inorganic chemistry, Chimie minérale, Crystallography, Cristallographie cristallogenèse, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Corrosion, Protection contre la corrosion, Corrosion prevention, Apatite hydroxylée, Hydroxyapatite, Hidroxiapatito, Corrosion électrochimique, Electrochemical corrosion, Corrosión electroquímica, Elektrochemische Korrosion, Dépôt électrolytique, Electrodeposition, Depósito electrolítico, Elektroplattieren, Irradiation électron, Electron irradiation, Irradiación electrón, Méthode potentiodynamique, Potentiodynamic method, Método potenciodinámico, Protection corrosion, Corrosion protection, Protección corrosión, Korrosionsschutz, Revêtement céramique, Ceramic coating, Revestimiento cerámico, Keramikbeschichten, Résistance corrosion, Corrosion resistance, Resistencia corrosión, Korrosionsbestaendigkeit, Titane alliage, Titanium alloy, Titanio aleación, Titanlegierung, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Ceramics, Mechanical properties, Metals and alloys, Microstructure, and SEM

In our present study, the Ti―6Al―4V alloy surface was modified by irradiating with the high energy low current DC electron beam (HELCDEB) using 700 keV DC accelerator. Following this, the HELCDEB treated surface was coated with hydroxyapatite by adopting electrodeposition method. The microstructure and hardness of HELCDEB treated Ti―6A1―4V alloy with and without electrodeposited hydroxyapatite were investigated. Also, the electrochemical corrosion characteristics of the samples in simulated body fluid (SBF) was studied by potentiodynamic polarisation and electrochemical impedence techniques (EIS) which showed an enhanced corrosion resistance and revealed an improved life time for the hydroxyapatite coating developed on the HELCDEB treated Ti―6A1―4V alloy than the untreated sample.

Inorganic chemistry, Chimie minérale, Crystallography, Cristallographie cristallogenèse, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Electrodes: préparations et propriétés, Electrodes: preparations and properties, Cathode, Cátodo, Fer Lithium Phosphate Mixte, Iron Lithium Phosphates Mixed, Hierro Litio Fosfato Mixto, Haute température, High temperature, Alta temperatura, Liaison covalente, Covalent bond, Enlace covalente, Procédé sol gel, Sol gel process, Procedimiento sol gel, Revêtement surface, Surface coating, Spinelles, Spinels, Espinelas, Stabilité thermique, Thermal stability, Estabilidad térmica, Traitement surface, Surface treatment, Tratamiento superficie, LiFePO4, High temperature performance, High voltage LiNi0.5Mn1.5O4 cathode, Sol-gel, and Surface coating with LiFePO4

A dramatic improvement in the elevated temperature performance of spinel phase LiNi0.5Mn1.5O4 cathode is achieved by surface modification with LiFePO4. Presence of strong covalent P-O bond in the olivine phase translates necessary thermal stability to LiNi0.5Mn1.5O4 cathode and renders ~89% of initial reversible capacity after 50 cycles at 55 °C. Though the LiFePO4 modified phase exhibits marginal reduction in the initial reversibility than bare LiNi0.5Mn1.5O4, displayed exceptional capacity retention characteristics irrespective of either ambient or elevated temperature.

Inorganic chemistry, Chimie minérale, Crystallography, Cristallographie cristallogenèse, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Electrodes: préparations et propriétés, Electrodes: preparations and properties, Anode, Anodo, Batterie lithium, Lithium battery, Cinétique, Kinetics, Cinética, Electrolyte solide, Solid electrolyte, Electrólito sólido, Graphite, Grafito, Lithium Titanate, Lithium Titanates, Litio Titanato, Procédé sol gel, Sol gel process, Procedimiento sol gel, Propriété électrochimique, Electrochemical properties, Propiedad electroquímica, Revêtement, Coatings, Revestimiento, Spinelles, Spinels, Espinelas, Stabilité thermique, Thermal stability, Estabilidad térmica, Synthèse hydrothermale, Hydrothermal synthesis, Traitement surface, Surface treatment, Tratamiento superficie, 8245F, Lithium rechargeable batteries, Solid electrolyte interphase, Spinel lithium titanium oxide, and Surface modification

We introduce an effective way to improve the electrochemical properties of graphite anodes by Li4Ti5O12 (LTO) coating for lithium rechargeable batteries. LTO coated graphite is prepared by a sol-gel method coupled with hydrothermal reaction. LTO coating renders the electrochemical performance of graphite to be significantly improved compared to pristine graphite. Moreover, LTO coating layers affect the stability of the solid electrolyte interphase (SEI) by making an even SEI film without further electrolyte decomposition and thus making it more stable. Also, LTO coating layers prevent the electrolyte decomposition species from going into the interior graphite, proving that LTO coating can contribute to not only the electrochemical properties of graphite but also its thermal stability.

Inorganic chemistry, Chimie minérale, 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 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), 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, Autres interactions de la matière avec les particules et le rayonnement, Other interactions of matter with particles and radiation, Microondes et radiofréquences (à l'exclusion des résonances), Microwave and radio-frequency interactions (excluding resonances), Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Méthodes de nanofabrication, Methods of nanofabrication, Absorption hyperfréquence, Microwave absorption, Absorción hiperfrecuencia, Adsorption, Constante diélectrique complexe, Complex permittivity, Constante dieléctrica compleja, Constante diélectrique, Permittivity, Diffraction RX, XRD, Fibre carbone, Carbon fibers, Matériau composite, Composite materials, Microscopie électronique balayage, Scanning electron microscopy, Microscopie électronique transmission, Transmission electron microscopy, Microstructure, Morphologie, Morphology, Mécanisme formation, Formation mechanism, Mecanismo formacion, Nanocristal, Nanocrystal, Oxyde de zinc, Zinc oxide, Zinc óxido, Perte diélectrique, Dielectric losses, Semiconducteur, Semiconductor materials, Synthèse nanomatériau, Nanomaterial synthesis, Síntesis nanomaterial, Traitement surface, Surface treatments, ZnO, Coating materials, Nanostructured materials, Oxide materials, and Semiconductors

Morphology control is crucial to the applications of zinc oxide (ZnO) nanocrystals. In this study, ZnO nanostructures with varying morphologies were coated on the surface of carbon fibers (CFs). Scanning electron microscopy (SEM), X-ray diffraction (XRD), and transmission electron microscopy (TEM) were conducted to characterize the morphology and structure of the ZnO-coated CFs (ZCCFs). SEM images reveal that ZnO nanostructures with different morphologies and microstructures are uniformly coated on CFs. XRD and TEM studies show that the products consist of crystallized hexagonal wurtzite ZnO. The complex permittivity and permeability of the ZCCF/paraffin composites with two different ZnO morphologies (floccus and particle) were measured in the frequency range of 1―18 GHz and their microwave absorption properties were investigated. Results show that the ZCCF/paraffin composite containing 30 wt.% floccus-shaped ZnO exhibits significantly higher dielectric loss and better microwave absorption properties as compared to that with particle-shaped ZnO. It is demonstrated that the floccus-like ZnO-coated CFs are a promising microwave absorbent with light weight, small thickness, strong absorption, and broad bandwidth.

Inorganic chemistry, Chimie minérale, Crystallography, Cristallographie cristallogenèse, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Corrosion, Protection contre la corrosion, Corrosion prevention, Argent, Silver, Plata, Silber, Cuivre, Copper, Cobre, Kupfer, Passivation, Pasivación, Passivierung, Poudre métallique, Metal powder, Polvo metálico, Metallpulver, Résistance oxydation, Oxidation resistance, Resistencia a la oxidación, Résistivité couche, Sheet resistivity, Resistividad capa, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Antioxidation, Combinative method, Copper particles, and Surface modification

The specific goal of the present study is to evaluate the surface performance of the copper particles and get excellent copper powder by surface modification. This paper proposes a combinative modification method integrating passivation, silver-coated, and coupling agent. As a result, after 600 h at room temperature the copper powder has the stabilization improved and is well combined with organic matters, and the sheet resistance of the film fabricated by the copper conductive filler is reduced to 15 mΩ. The performance of the copper powder has been greatly enhanced by the combinative modification, and the cost of the copper conductive filler is decreased significantly by this method. The results indicate that the combinative surface modification method can be used for practical electronic application.

Inorganic chemistry, Chimie minérale, 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), 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, Alliage mémoire forme, Shape memory alloy, Aleación memoria forma, Couche mince, Thin films, Couche oxyde, Oxide layer, Capa óxido, Diffraction RX, XRD, Microscopie électronique balayage, Scanning electron microscopy, Microstructure, Nickel alliage, Nickel alloys, Pulvérisation cathodique, Cathode sputtering, Spectre photoélectron RX, X-ray photoelectron spectra, Spectrométrie FTIR, Fourier-transformed infrared spectrometry, Espectrometría FTIR, Spectrométrie dispersive, Dispersive spectrometry, Espectrometría dispersiva, Titane alliage, Titanium alloys, Traitement chimique, Chemical treatment, Tratamiento químico, Traitement surface, Surface treatments, Fourier Transform of Infrared Radiation (FTIR), Scanning electron microscopy (SEM), Shape memory alloys, X-ray diffraction (XRD), and X-ray photo-electron spectroscopy (XPS)

NiTi thin-films were deposited by DC magnetron sputtering from single alloy target (Ni/Ti:45/55 at.%). The rate of deposition and thickness of sputter deposited films were maintained to ~35 nm min―1 and 4 μm respectively. A set of sputter deposited NiTi films were selected for specific chemical treatment with the solution comprising of de-ionized water, HF and HNO3 respectively. The influence of chemical treatment on surface characteristics of NiTi films before and after chemical treatment was investigated for their structure, micro-structure and composition using different analytical techniques. Prior to chemical treatment, the composition of NiTi films using energy dispersive X-ray dispersive spectroscopy (EDS), were found to be 51.8 atomic percent of Ti and 48.2 atomic percent of Ni. The structure and morphology of these films were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD investigations, demonstrated the presence of dominant Austenite (110) phase along with Martensite phase, for untreated NiTi films whereas some additional diffraction peaks viz. (100), (101), and (200) corresponding to Rutile and Anatase phase of Titanium dioxide (TiO2) along with parent Austenite (110) phase were observed for chemically treated NiTi films. FTIR studies, it can be concluded that chemically treated films have higher tendency to form metal oxide/hydroxide than the untreated NiTi films. XPS investigations, demonstrated the presence of Ni-free surface and formation of a protective metal oxide (TiO2) layer on the surface of the films, in both the cases. The extent of the formation of surface oxide layer onto the surface of NiTi films has enhanced after chemical treatment.

Inorganic chemistry, Chimie minérale, 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, Structure des liquides et des solides; cristallographie, Structure of solids and liquids; crystallography, Nanomatériaux : agrégats, nanoparticules, nanotubes et nanocristaux, Nanoscale materials: clusters, nanoparticles, nanotubes, and nanocrystals, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Méthodes de nanofabrication, Methods of nanofabrication, Analyse thermique différentielle, Differential thermal analysis, Cinétique, Kinetics, Coprécipitation, Coprecipitation, Cristallisation, Crystallization, Diffraction RX, XRD, Diffraction électron sélection aire, SAED, Microscopie électronique transmission, Transmission electron microscopy, Microstructure, Mécanisme croissance, Growth mechanism, Mecanismo crecimiento, Nanocristal, Nanocrystal, Oxyde de titane, Titanium oxide, Titanio óxido, Oxyde de zinc, Zinc oxide, Zinc óxido, Spectrophotométrie, Spectrophotometry, Synthèse nanomatériau, Nanomaterial synthesis, Síntesis nanomaterial, Traitement surface, Surface treatments, Coprecipitation process, Crystallite growth kinetics, Red-shifted effect, and TiO2 surface modification

The nanocrystallite growth of TiO2 surface modification with 9 mol% ZnO prepared by a coprecipitation process has been studied. Thermogravimetric and differential thermal analysis (TG/DTA), X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and UV-VIS-NIR spectrophotometry have been utilized to characterize the TiO2 nanocrystallites surface modification with 9 mol% ZnO (denoted by T-9Z). The DTA result shows that the anatase TiO2 first formed at 533 K and the completion of anatase TiO2 crystallization occurred at 745 K for the T-9Z freeze-dried precursor powders. XRD results reveal that the anatase and rutile TiO2 coexist when the T-9Z freeze-dried precursor powders were calcined at 523-973 K for 2 h. When the T-9Z freeze-dried precursor powders were calcined at 973 K for 2 h, rutile TiO2 was the major phase, and the minor phases were anatase TiO2 and Zn2Ti3O8. The phase was composed of the rutile TiO2 and Zn2TiO4 for the T-9Z freeze-dried precursor powders after calcination at 1273 K for 2 h. The growth kinetics of TiO2 nanocrystallites in T-9Z powders were described as: D2A.9 = 2.42 × 105 × exp(-39.9 × 103 /RT)and D2R.9 = 8.49 × 105 × exp(-47.6 × 103/RT) for anatase and rutile TiO2 nanocrystallites respectively. The analysis results of UV/VIS/NIR spectra reveal that the T-9Z freeze-dried precursor powders after calcination have a red-shifted effect with increasing calcination temperature and can be used as a UVA-attenuating agent.

Inorganic chemistry, Chimie minérale, 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, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Abrasion, Carbone, Carbon, Carbure de silicium, Silicon carbide, Silicio carburo, Carbure de zirconium, Zirconium carbide, Zirconio carburo, Infiltration état fondu, Melt infiltration, Matériau composite, Composite materials, Microstructure, Réaction liquide solide, Liquid solid reaction, Reacción líquido sólido, Traitement par plasma, Plasma assisted processing, Traitement surface, Surface treatments, Ceramics, Corrosion, Liquid-solid reactions, and Phase diagrams

C/C―ZrC―SiC composites coated with ZrC―SiC were prepared by precursor infiltration pyrolysis combined with reactive melt infiltration. The microstructure and ablation behavior of the composites before and after ablation were investigated. The composites exhibit good ablation resistance with a surface temperature of over 2300 °C. After ablation for 120 s, the mass and linear ablation rates of the composites are 0.0045 g/s and 0.0048 mm/s, respectively. The great ablation resistance of the composites is attributed to the formation of continuous integrated SiO2―ZrO2―SiC ceramic layer sealed the pores of the composites surface during ablation.