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The rapid realization of efficient anti-icing coatings on diverse substrates is of vital value for practical applications. However, current approaches for rapid preparations of anti-icing coatings are still deficient regarding their surface universality and accessibility. Here, we report a simple processing approach to rapidly form icephobic liquid-like polydimethylsiloxane (PDMS) brushes on various substrates, including metals, ceramics, glass, and plastics. A poly(dimethylsiloxane), trimethoxysilane is applied as a reactant under the catalysis of a minimal amount of acid formed by hydrolysis of dichlorodimethylsilane. With such an advantage, this approach is approved to be applicable of coating metal surfaces with less corrosion. The distinctive flexibility of the PDMS chains provides a liquid-like property to the coating showing low contact angle hysteresis and ice adhesion strength. Notably, the ice adhesion strength remains similar across a wide temperature window, from −70 to −10 °C, with a value of 18.4 kPa. The PDMS brushes demonstrate perfect capability for resisting acid and alkali corrosions, ultra-violet degradation, and even tens of icing/deicing cycles. Moreover, the liquid-like coating can also form at supercooling conditions, such as −20 °C, and shows an outstanding anti-icing/deicing performance, which meets the in situ coating reformation requirement under extreme conditions when it is damaged. This instantly forming anti-icing material will benefit from resisting instantaneous ice accretion on surfaces under extremely cold conditions. [ABSTRACT FROM AUTHOR]

VO2-based thermochromic coatings have gained much attention in temperature-adaptive smart windows, and constructing multilayer film structures is the main way to obtain high thermochromic performances. Based on the self-developed objective-orientated automatic optimization code, the present research realized customized designs of thermochromic multilayer coatings composed of VO2, TiO2, and SiO2 from the objectives of visible luminance (Tlum) and solar light modulation (ΔTsol). The TiO2/VO2/s, VO2/TiO2/s, TiO2/VO2/TiO2/s, and SiO2/TiO2/VO2/TiO2/s (s denotes substrate) multilayer film systems were then prepared by magnetron sputtering and vacuum controllable heating, with their structures, insulator-metallic transition, and thermochromic properties being carefully studied. The result showed that the best trade-off between high Tlum and high ΔTsol was achieved for these film assemblies, and solar light modulation was mainly limited at the near-IR wavelength region of the solar spectrum, with the difference between cool- and hot-state Tlum being greatly reduced. In the case of the four-layer SiO2/TiO2/VO2/TiO2/s, very high average Tlum (60%) and high ΔTsol (14%) were obtained. A 100 × 100 mm2 of the SiO2/TiO2/VO2/TiO2/s was also prepared, and it showed an obvious temperature adjustment, and the service life can last for 14 years under normal weather conditions. Not limited to the prepared multilayer film systems, the methodology used here is also suitable for the fast development of other multilayer film systems. [ABSTRACT FROM AUTHOR]

The tetrahedral amorphous carbon (ta-C) coatings are deposited on piston rings to improve the tribological property of the piston ring-cylinder liner system of the internal combustion engines. The deposition parameters are optimized by molecular dynamics simulation to reduce the cost of coatings' fabrication. The ta-C coatings with higher sp3 fraction, lower friction coefficient, and superior anti-wear properties are achieved by optimizing the incident energy and substrate temperature of carbon atoms. The second nearest-neighbor modified embedded-atom method potential and Tersoff potential are used to describe the interatomic interactions. The effects of the incident energy of the carbon atoms and substrate temperature on the deposition properties of the ta-C coatings are discussed. The numerical results show that the ta-C coatings with high sp3 fraction, high density, and good interface mixing are obtained, and the deposition properties of the ta-C coatings are improved. [ABSTRACT FROM AUTHOR]

PVD technologies, including vacuum arc evaporation and DC-magnetron sputtering, have been utilized in industrial settings since the early 1980s for depositing protective coatings. These coatings encompass a range of materials such as metal nitrides, carbonitrides, oxides, oxynitrides, and DLC, serving diverse applications such as cutting and forming tools, automotive components, and decoration. Vacuum arc evaporation generates a highly energized and ionized particle flux toward the substrate, while "classical" gas-ion-dominated direct current magnetron sputtering (DCMS) has limitations in generating ionized and energetic species of the sputtered target material. The development of High-Power Impulse Magnetron Sputtering (HiPIMS) has exhibited significant potential in addressing DCMS's limitations by enabling the production of highly energetic particles. This innovation, with its industrial applicability for protective coatings, was introduced around 2010. This paper aims to provide an industrial perspective on HiPIMS, serving as a guide for scientists and engineers in comprehending and implementing HiPIMS solutions. It covers historical context and fundamental characteristics. Basic features as well as state-of-the-art configurations of PVD systems are also described. Graphical representations of experimental results illustrate HiPIMS features, including operational modes, deposition rate effects, thickness uniformity, and sustainability, particularly in terms of energy efficiency. The discussion focuses on the application prospects, advantages, and constraints of industrially applied HiPIMS protective coatings, emphasizing cutting and forming tools, within the context of the findings presented. [ABSTRACT FROM AUTHOR]

We develop a semi-analytical model of self-diffusioosmotic transport in active pores, which includes advective transport and the inverse chemical reaction that consumes solute. In previous work [Antunes et al., Phys. Rev. Lett. 129, 188003 (2022)], we have demonstrated the existence of a spontaneous symmetry breaking in fore-aft symmetric pores that enables them to function as a micropump. We now show that this pumping transition is controlled by three timescales. Two timescales characterize advective and diffusive transport. The third timescale corresponds to how long a solute molecule resides in the pore before being consumed. Introducing asymmetry to the pore (either via the shape or the catalytic coating) reveals a second type of advection-enabled transition. In asymmetric pores, the flow rate exhibits discontinuous jumps and hysteresis loops upon tuning the parameters that control the asymmetry. This work demonstrates the interconnected roles of shape and catalytic patterning in the dynamics of active pores and shows how to design a pump for optimum performance. [ABSTRACT FROM AUTHOR]

Polyelectrolytes can electrophoretically be driven through nanopores in order to be detected. The respective translocation events are often very fast and the process needs to be controlled to promote efficient detection. To this end, we attempt to control the translocation dynamics by coating the inner surface of a nanopore. For this, different charge distributions are chosen that result in substantial variations of the pore–polymer interactions. In addition and in view of the existing detection modalities, experimental settings, and nanopore materials, different types of sensors inside the nanopore have been considered to probe the translocation process and its temporal spread. The respective transport of polyelectrolytes through the coated nanopores is modeled through a multi-physics computational scheme that incorporates a mesoscopic/electrokinetic description for the solvent and particle-based scheme for the polymer. This investigation could underline the interplay between sensing modality, nanopore material, and detection accuracy. The electro-osmotic flow and electrophoretic motion in a pore are analyzed together with the polymeric temporal and spatial fluctuations unraveling their correlations and pathways to optimize the translocation speed and dynamics. Accordingly, this work sketches pathways in order to tune the pore–polymer interactions in order to control the translocation dynamics and, in the long run, errors in their measurements. [ABSTRACT FROM AUTHOR]

The stability and accuracy of atomic devices can be degraded by the evolution of their cell inner atmosphere. Hence, the undesired entrance or leakage of background or buffer gas, respectively, that can permeate through the cell walls, should be slowed down. In this work, we investigate helium permeation in microfabricated alkali vapor cells filled with He and whose windows are made of borosilicate glass (BSG) or aluminosilicate glass (ASG). The permeation is then derived from routine measurements of the pressure-shifted hyperfine transition frequency of an atomic clock. We first confirm that ASG reduces the He permeation rate by more than two orders of magnitude, in comparison to BSG. In addition, we demonstrate that Al 2 O 3 thin-film coatings, known to avoid alkali consumption in vapor cells, can also significantly reduce He permeation. The permeation through BSG is thereby reduced by a factor up to 130, whereas the one through ASG is decreased by a factor up to 5.0 compared to uncoated substrates. These results may contribute to the development of miniaturized atomic clocks and sensors with improved long-term stability or sensitivity. [ABSTRACT FROM AUTHOR]

An ablation resistant coating with self-transpiration cooling effect was prepared on the surface of aluminum alloy by dilution effect of high speed laser cladding. The coatings mainly contain ablation resistant phases ZrB 2 and SiC, and low-melting phases Al and Al 3.21 Si 0.47. The ablation property of coatings was investigated at different heat fluxes (35.39, 70.77, 106.16, 141.54) MW⸱m−2. The mass ablation rate increased gradually, and the morphology of ablation region changed significantly with the increased heat flux. The self-transpiration cooling effect of coatings was studied by phase, morphology, and element distribution of ablation region. The self-transpiration cooling effect weakened the oxidation behavior of ZrB 2 and SiC at heat fluxes of 35.39 and 70.77 MW⸱m−2 and protected the coating from being exhausted when the heat fluxes were 106.16 and 141.54 MW⸱m−2. [ABSTRACT FROM AUTHOR]

This study prepared the 7YSZ ceramic coatings based on AlCoCrFeNi bond coating by APS and PS-PVD methods, respectively. Two AlCoCrFeNi/7YSZ thermal barrier coating systems with different microstructures of ceramic coatings were obtained, and oxidation experiments at 1000 °C and 1100 °C were carried out for the two thermal barrier coating systems. The results showed that the AlCoCrFeNi/7YSZ(PS-PVD) thermal barrier coating system exhibits superior oxidation resistance compared to the AlCoCrFeNi/7YSZ(APS) thermal barrier coating system at 1000 °C and 1100 °C, which was attributed to the ceramic coating with a unique feather-columnar structure prepared by PS-PVD. Both thermal barrier coatings in this study produced a continuous and dense TGO layer composed of Al 2 O 3 after oxidation experiments. The oxidation rate constants k p of this study's two thermal barrier coatings were lower than the selected MCrAlY/YSZ thermal barrier coating systems under the same experimental conditions. It indicates that the AlCoCrFeNi bond coating exhibited excellent oxidation resistance and possesses the potential to be a new type of bond coating material. [ABSTRACT FROM AUTHOR]

Graphite substrate, as one of metal-organic chemical vapor deposition (MOCVD) equipment, often fails due to corrosion and powder loss during service. SiC is an ideal protective coating on graphite substrate surfaces due to its excellent properties. Currently, the preparation of SiC coating on large-size graphite substrates by chemical vapor deposition (CVD) in batches is extensively concerned. The coating was affected by various deposition processes during deposition due to the complexity of CVD. The deposition process of CVD needed to be optimized for batch preparation of large-size graphite plate/SiC coating. However, the temperature field and airflow field distribution inside the CVD equipment and the variation of SiC deposition mass fraction were challenging to obtain by instrumental measurement in the experiments. Herein, the optimization of the CVD process was guided by using Computational Fluid Dynamics (CFD) simulation. Five deposition processes, such as graphite plate placement, diameter, deposition temperature, reaction gas flow, and graphite plate rotational speed, were selected for the investigation. The simulation results were validated by CVD experiments. Optimal process parameters for the batch preparation of large-size graphite plate/SiC coating by CVD were obtained. Guidance for future batch production of coating on a large-size substrate by CVD was provided. [ABSTRACT FROM AUTHOR]

Monotonic tensile behavior of plain-woven SiC f /SiC ceramic matrix composites is investigated at 1200 °C and 1350 °C in water–oxygen environments. In addition, tensile–tensile fatigue behavior at 1200 °C in water–oxygen environments is discussed. Specimens are prepared using chemical vapor infiltration (CVI) process. To enhance their resistance to oxidation in high-temperature water–oxygen environments, environmental barrier coatings (EBCs) are deposited on their surface. Two rows of film cooling holes (FCHs) with 0.5 mm diameter, each row consisting of five FCHs, are designed to compare the effects of two different hole spacings on specimen fatigue and tensile performance. The evolution of strain and normalized modulus during fatigue cycling is investigated in detail. Microstructures of specimens that failed under tensile and fatigue conditions are observed using scanning electron microscopy (SEM), and elemental analyses of specimens after fatigue test failure are performed using energy-dispersive spectroscopy (EDS). The results reveal that tensile strength of specimens with large FCH spacing is greater than that of specimens with small FCH spacing. However, fatigue performance of specimens with small FCH spacing was better than that of specimens with large FCH spacing. This phenomenon is caused by a reduction in strength due to stress concentration effect near holes with small FCH spacing. Holes with large FCH spacing are closer to the specimen edge during fatigue test, leading to high failure rate. The oxidation and embrittlement that surround holes caused by FCHs compromised structural integrity of the specimen and allowed water–oxygen environment to penetrate the specimen interior. This has significant impact on mechanical performance of the material. [ABSTRACT FROM AUTHOR]

[Display omitted] • PO 4 3−-doping and Li 3 PO 4 -coating of dual modification of LiNiO 2 are achieved. • PO 4 3− doping improves the reversibility of crystal structure. • PO 4 3− doping induces surface structural transformation of the material. • Li 3 PO 4 coating could ameliorate the interface stability. Lithium nickel oxide (LiNiO 2) cathode materials are featured with high capacity and low cost for rechargeable lithium-ion batteries but suffer from severe structure and interface instability. Bulk doping together with surface coating has been proven to be an efficient approach to improve the inner structure and interfacial stability of the LiNiO 2 cathode material. Nevertheless, the role of anion doping seems to be quite different from that of cation doping, and a deep insight will be desirable for the structure design of the LiNiO 2 cathode material. In this paper, PO 4 3−-doped and Li 3 PO 4 -coating of dual modification of LiNiO 2 are achieved via a facile approach. It is demonstrated that the PO 4 3− anions are doped into the tetrahedron vacant sites of the crystal structure, alleviating the phase transition and improving the reversibility of crystal structure. Besides, the Li 3 PO 4 coating layer ameliorates the interface stability to restrain the side reactions. Therefore, the dual modification enhances overall structural stability of the material to provide excellent performance. Moreover, the consumption of the Li residues by the formation of Li 3 PO 4 coating layer, and the enlarged interlayer spacing of the crystal structure by PO 4 3− doping can facilitate the Li+ ions diffusion, resulting in a superior rate capability. [ABSTRACT FROM AUTHOR]

We present a method to model the gas permeation through silicon-oxide thin film coatings that are afflicted with nanoscale defects. With it, we are able to give an estimation of the diffusion coefficient in bulk by subtracting the influence of the defects. The model is based on data obtained from positron annihilation spectroscopy, which is processed to yield possible defect allocation patterns of the coatings. For a systematic evaluation of these patterns, a path through the coating is calculated and then subjected to in-depth analysis to evaluate the used approach as well as to interpret the results for insights on the permeation mechanisms. The model appears to function as intended and no unexpected behaviour is observed. The defect volume share is overestimated, which can be retraced to the underlying algorithm, and a correction method is applied to the resulting bulk diffusion coefficient. The model gives reasonable results both for oxygen and water vapor permeation. These results can be used in following works that build on the presented model. [ABSTRACT FROM AUTHOR]

The present study focuses on the removal of ineffective hydroxyl surface (B–OH) of the shell of pristine boron (B) particles, followed by its modification using a low-cost, eco-friendly, and non-hazardous ethylene glycol (EG). Subsequently, very small-sized titanium dioxide (TiO 2) particles are coated onto the boron surface by adding titanium tetraisopropoxide (TTIP) precursors at room temperature. Characterization techniques were employed to investigate the structure and morphology of these materials. FTIR, XPS, and TEM analysis reveal that EG effectively removes ineffective boron hydroxyl surfaces and modifies the surface through passivation by its surface functionalities. Furthermore, EG assists in the coating very small-sized TiO 2 particles on the boron surface. Thermal stability tests show that the modified boron surface and TiO 2 -coated boron surface exhibit earlier oxidation of the core boron compared to pristine boron. This enhanced capability for earlier oxidation of core boron was further investigated in the shock tube and bomb calorimeter for measurement of ignition delay time and heat of combustion. The findings demonstrate that room temperature synthesized TiO 2 -coated B particles (ignition delay time of ∼181 μs and heat of combustion of ∼17.3 kJ/g) outperform pristine B particles (ignition delay time of ∼284 μs and heat of combustion of ∼13.2 kJ/g). This improvement is attributed to the removal of ineffective boron hydroxyl surfaces, surface modification, uniform coating with very small TiO 2 particles, the catalytic effect of TiO 2 on oxygen diffusion, and effective oxidation of core boron. This study suggests that efficient energetic material can be achieved at room temperature with no potential harm to the environment. [ABSTRACT FROM AUTHOR]

Rare earth elements (Dy, Ho, Er, Tm, and Lu), characterized by low-diffusivity in silicate melts, were designed as defect-fluorite structure high-entropy material (Dy 0.2 Ho 0.2 Er 0.2 Tm 0.2 Lu 0.2) 2 Hf 2 O 7 to determine its resistance to calcium-magnesia-alumina-silicon (CMAS) attack. The results indicate that corrosion reactions preferentially crystallize anorthite and garnet phases in the front of molten CMAS at 1300 °C, which alleviates rapid infiltration of CMAS. The reaction between the melt and (Dy 0.2 Ho 0.2 Er 0.2 Tm 0.2 Lu 0.2) 2 Hf 2 O 7 forms mixture layers comprising apatite and fluorite phases at 1500 °C, which are accompanied by the prompt exhaustion of CMAS. The capability of intaking RE determines the formation mechanisms of apatite with two different structures. The study reveals that the high-entropy material effectively resists molten CMAS attack at 1300 °C; however, its effectiveness in preventing rapid corrosion decay diminishes at 1500 °C. Factors affecting reaction control were discussed at each condition to elucidate the interactions between the multi-cation hafnate material and silicate deposits. This study represents a significant stride towards advancing high-entropy hafnate thermal barrier coating material applications in aerospace engineering. [ABSTRACT FROM AUTHOR]

In this work, the Y 3 Al 5 O 12 (YAG) coatings prepared by atmospheric plasma spraying were found to have a thermal expansion coefficient of 8.51 × 10-6K-1 from 473 to 1673K and a thermal conductivity of 2.41 W/(m∙K) at 1273K as well as a Young's modulus of 89.4 ± 9 GPa and an average hardness of 6.79 ± 0.24 GPa. Their excellent mechanical and thermal-physical properties have promoted them as thermal/environmental barrier coating (T/EBC) materials. Multi-layered Y 3 Al 5 O 12 /Yb 2 SiO 5 /Yb 2 Si 2 O 7 (YAG/YbMS/YbDS) T/EBCs were deposited on SiC based substrate. Thermal cycling and water vapor corrosion behavior of the YAG/YbMS/YbDS T/EBCs were also investigated. The cyclic oxidation tests at 1573K showed that the coatings had excellent resistance to thermal cycling, with an average lifetime of 442 ± 10 cycles. The initial oxidation of the Si layer at the edge, resulting in the formation of a 4.8 μm thick thermally grown oxide (TGO), coupled with the volumetric changes and the associated phase transformation stress, led to the delamination of the coatings from the edges. Due to the very low oxygen diffusion rate of YAG layer, the thickness of TGO was only 1.2 μm after steam corrosion for 40 h. The amorphous crystallization as well as thermal mismatch stresses were the main reasons for the coating failure. [ABSTRACT FROM AUTHOR]

A set of novel (AlTiCrVTa)N x coatings are synthesized by DC magnetron sputtering to methodically investigate the effect of nitrogen content on the microstructure, mechanical and tribological properties and oxidation behavior of the coatings for the first time. As the nitrogen content increases, the coating structure transitions from amorphous to a simple fcc structure, accompanied by a change of preferred orientation from (200) to (111) and an enhancement in crystallinity. The coating morphology changes from featureless glassy to columnar crystals. The highest nanohardness of 38.1 GPa and the best wear rate of 4.9 × 10−7 mm3/Nm are achieved at 43.3 at.% nitrogen content. The friction coefficient exhibits a downward trend with rising nitrogen content, reaching the lowest value of 0.47 at 49.8 at.% nitrogen content. The oxidation tests reveal that the oxidation resistance deteriorates with increasing nitrogen content, caused by the looser structure and large-sized grain boundaries. [ABSTRACT FROM AUTHOR]

Zinc (Zn) distinguishes itself as an excellent candidate for temporary orthopaedic implants due to its advantageous corrosion rate compared to other biodegradable metallic materials like Mg and Fe. The present research involved the fabrication of a porous, corrosion-resistant, and biocompatible plasma electrolytic oxidation (PEO) coating on a Zn–1Mg alloy. Bioactivity was imparted to the PEO coating by incorporating hydroxyapatite (HA) and silver-incorporated hydroxyapatite (SHA) nanoparticles into it by synergising the PEO process with electrophoretic deposition (EPD) in a single step. FESEM and EDS are utilised to confirm the porous PEO oxide layer formation and its sealing by HA and SHA particles in PEO-EPD coating. The coatings' phase composition, surface roughness, scratch resistance, and wettability were evaluated to assess their suitability for temporary implant applications. The coatings' wettability and roughness significantly improved compared to the untreated substrate, rendering it suitable for orthopaedic implant applications. The scratch resistance of the PEO coating was satisfactory and showed additional improvement in the thicker film with lower porosity, achieved through the combined PEO-EPD process. The electrochemical corrosion test in biological media revealed that the PEO coating enhanced the degradation resistance of Zn–1Mg, which was further enhanced by incorporating HA and SHA particles into the PEO coating. The in-vitro bioactivity test in simulated body fluid (SBF) and cytotoxicity test using L929 (Mouse fibroblast) cells proved that adding HA made the fabricated PEO coating biologically more favourable. Furthermore, the SHA-incorporated PEO coating is antibacterial against E. coli bacterial strains, enabling protection against post-implantation infections. • ZnO-HA ceramic composite coating developed on Zn–1Mg by PEO. • ZnO-HA coating showed 3 orders lower i corr compared to bare alloy. • Ceramic-composite coating proved to be bioactive and biocompatible. • Silver-incorporated coating exhibited the bactericidal property. [ABSTRACT FROM AUTHOR]

Background: The current nursing procedure after fractional carbon dioxide (fCO2) is complex and needs to be optimized. The present study was conducted to evaluate the assisting effect of filament coating system after fCO2 laser treatment. Methods: Chinese individuals aged from 18 to 65 years diagnosed as photoaging or atrophic acne scar were recruited and each participant was treated with one single pass of fCO2 laser. A split face was randomly assigned as treatment side or control side. For control side, conventional procedure was topically applied respectively, including desonide cream two times for 3 days, fusidic acid cream two times for 7 days, and recombinant human epidermal growth factor (RhEGF) gel four times for 7 days; for treating side, a filament coating system was applied immediately after one application of fusidic acid cream, desonide cream and RhEGF, and removed 3 h later, for 3 days. Erythema, edema, crust, and pain on both sides were scored from 0 to 10 before and 1, 2, 4, and 7 days after fCO2 laser treatment. Stratum corneum hydration (SCH) and sebum of forehead and cheek on both sides were also measured by using Corneometer‐Sebumeter. Results: Twenty photoaging and 11 atrophic acne scar participants finished the observation. All of them complained of erythema, edema, crust, and pain after fCO2 laser treatment, and the scores decreased as time passed by. There were no statistical significances of erythema, edema, crust, pain, SCH, and sebum between treating side and control side at each observation time. Conclusion: Filament coating system was effective, safe, convenient, and economic in assisting recovery of ablative fCO2 laser, which might be a new option for additional nursing procedure. [ABSTRACT FROM AUTHOR]

In this study, we aim to quantify coating uniformity and correlate fluorescence intensity to drug loading for drug-coated angioplasty balloons (DCB) coated with 5, 10, 15, or 20 layers of poly(lactic-co-glycolic acid) nanoparticles (NPs) entrapped with quercetin. Uniformity was quantified from histograms and horizontal line profiles of microscopic fluorescent images acquired with sample specific parameters, and cracks in the coating were measured and counted. The fluorescence of images acquired with global parameters was correlated with quercetin loading measured via gravimetric/HPLC analysis. More layers on DCBs may be associated with less uniform coatings, as indicated by differences in histogram standard deviations. The line profile percent deviation from average for each sample was <20%. Cracks were present on all balloons, but their length was not significantly different between samples. The 5-layer DCBs had the fewest cracks, whereas the 15-layer DCBs had the most cracks. A strong positive correlation (R = 0.896) was identified between fluorescence intensity and drug loading. A relationship between the number of layers and coating uniformity seems to exist, but further investigations are required for confirmation. Fluorescence intensity appears to strongly predict drug loading, demonstrating that fluorescent imaging may be a viable alternative to drug release studies. [ABSTRACT FROM AUTHOR]

The corrosion behavior of electrodeposited nickel-based coatings with W, Mo, and TiOx as potential catalytic material for hydrogen evolution reaction (HER) in highly aggressive media, 0.5 M H2SO4 and 6 M KOH, is presented. A wide range of electrochemical and spectroscopic methods have been used, such as linear sweep voltammetry, open-circuit potential (OCP), electrochemical impedance spectroscopy (EIS), X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) to characterize the coatings before and after a residence time of 336 h in the model corrosion environment. The NiW alloy and the NiWTiOx composite coating demonstrate the best corrosion resistance in an acidic environment due to the stable tungstate phase formation (H0.33O3W and H2O4W) on the surface. In alkaline environments, all the systems studied show enviable resistance, but the alloys containing molybdenum stand out. [ABSTRACT FROM AUTHOR]

A review of the author's works proving the existence of the phenomenon of the electrochemical phase formation in metals and alloys via a supercooled liquid state stage is presented. This review presents all the stages of establishing the above phenomenon in chronological order, as well as examples of its scientific and practical application. The theoretical prediction of the phenomenon, its experimental observation, theoretical substantiation, and some experimental proofs confirming its existence are considered in detail. The mechanism and thermodynamic model of crystallographic texture formation in electrochemical coatings, developed on the basis of the concepts of the phase formation in electrodepositing metals/alloys, taking into account the intermediate stage of the supercooled liquid state, are discussed. Some areas of the practical application of the phenomenon in basic industries (metallurgy, power engineering, and space engineering), concerning the development of the technologies for obtaining electrochemical films/coatings/foils with enhanced properties, are presented. [ABSTRACT FROM AUTHOR]

An electrolyte based on the deep eutectic solvent reline (a mixture of choline chloride and urea) was used for electrodeposition of coatings containing nickel and cerium. It was shown that a decrease in temperature and an increase in the concentration of cerium(III) ions in the plating bath lead to an increase in the content of cerium in the electrodeposits. Under certain conditions of electrolysis, it was possible to prepare coatings that contain nanocrystalline nickel with the inclusion of up to 40–59 wt.% cerium. The kinetics and reaction mechanism of hydrogen evolution on electrodeposited coatings in an aqueous alkaline medium of 1 M NaOH were studied in detail using the methods of Tafel analysis and electrochemical impedance spectroscopy. It was stated that a significant increase in the electrocatalytic activity of the electrodeposited material is observed with an increase in the content of cerium in the coating. A possible mechanism of the process (Volmer-Heyrovsky reaction pathway) was proposed and equivalent circuits were developed that adequately describes the registered impedance hodographs. A comparison of the results obtained in this work with literature data showed that the coating fabricated in reline-based electrolytes exhibit a higher content of cerium, and therefore a higher electrocatalytic activity towards the hydrogen evolution reaction than coatings produced from electrolytes based on ethaline (a eutectic mixture of choline chloride and ethylene glycol). [ABSTRACT FROM AUTHOR]

This paper reports an ultra‐soft neural probe with a temporary high‐strength U‐section coating of polyethylene glycol (PEG) for the first time. Its fabrication is compatible with MEMS processes, and an ultrathin U‐section coating over the probe's back and sidewall is precisely formed by spinning and cold laser cutting. With this novel coating, the probe has both minimized cross‐sectional area and sufficient mechanical strength for low‐invasive penetration into the brain. Besides, the remained ultra‐soft deformable probe after PEG dissolution is expected to be the next generation of neural implants for chronic recording. © 2024 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Ceramic coatings were obtained by micro‐arc oxidation (MAO) on the surface of AA1060 pure aluminum in alkaline silicate electrolyte with the addition of graphene. The effects of graphene contents in the range of 0–.30 g/L in the electrolyte on surface morphology, corrosion resistance, and wear resistance of the ceramic coatings were investigated. The outer surface structure, outer surface element content, coating cross‐section structure, coating cross‐section element content, coating/substrate interface structure, and coating phase were characterized by scanning electron microscope and X‐ray diffraction. Potentiodynamic polarization and electrochemical impedance spectroscopy were used to evaluate the corrosion behavior of MAO samples in a 3.5‐wt% NaCl solution. In addition, the resistance to sliding and abrasive wear of the oxide coating were studied experimentally. The results show that the alkaline silicate electrolyte with the addition of graphene has a significant effect on the characteristics of MAO coating. The performance of micro‐arc oxide coatings is best when the graphene content in the electrolyte is.15 g/L, the average thickness of the film is 7.24 μm, the average pore size is 6.07 μm, the impedance value is approximately 4.01 × 106 Ω, and its friction coefficient is.55. [ABSTRACT FROM AUTHOR]

In order to improve the comprehensive performance of TC11 titanium alloy and make it more widely used in the field of oil and gas wells, cobalt oxide micro‐powder from 0 to 0.8 g·L−1 was added in the electrolyte. The effects of cobalt oxide micro‐powder concentration on properties of micro‐arc oxidation (MAO) coatings were analyzed by scanning electron microscopy, X‐ray diffraction, X‐ray photoelectron spectroscopy, and electrochemical workstation. With cobalt oxide micro‐powder increased, the oxide voltage increased, and the discharge coating micropores became more uniform. The increase in thickness and hardness also improved corrosion resistance. The comprehensive performance after added 0.6 g·L−1 of cobalt oxide was the best, with a doubling increase in thickness and hardness, reaching 32.1 µm and 721.2 HV, respectively. The corrosion rate reduced to 4.19 × 10−10 mm·a−1, which reduced by three orders of magnitude. In addition, the substrates and samples prepared with 0.6 g·L−1 cobalt oxidation were used for the erosion corrosion tests in different NaCl solutions, and it was found that the weight loss and rate of the MAO sample (slight corrosion) were lower than substrates, indicating that the cobalt oxide doped coatings had better corrosion resistance. [ABSTRACT FROM AUTHOR]

In the current work, the chemical etching process and hydrothermal method were used to create bio‐inspired superhydrophobic fluorine‐free tin oxide nanostructures on copper plates. Taguchi's experimental design was also used in investigating coating wettability characteristics based on fabrication parameters. Statistical analysis results demonstrated that the optimal superhydrophobic sample with a water contact angle of 163.40° ± 1.42° and contact angle hysteresis of 3.00° ± 0.80° could be fabricated under the following conditions: sodium hydroxide (2.00 M) as an etching solution, urea‐to‐tin chloride ratio 2.5:1, and 2.00 h reaction times. The effects of each synthesis parameter on the obtained sample's superhydrophobicity were evaluated through multiple one‐variable‐at‐a‐time experiments. Testing the chemical stability of the optimal sample revealed that it was more resistant to deterioration in an alkaline environment (8–10) than in an acidic environment (4–6). The resulting superhydrophobic sample was analyzed by a delay test for water droplets freezing on its surface to determine whether ice formed and accumulated. The created bio‐inspired honeycomb‐like nanocoating demonstrated exceptional mechanical robustness and good anti‐icing performance after 10 consecutive icing cycles. These results indicated that superhydrophobic coatings could be easily and economically produced without using fluoropolymers and silanes on aluminum substrates. [ABSTRACT FROM AUTHOR]

The failure behavior and load-carrying capacity of Nomex honeycomb sandwich panels under three-point bending are experimentally and numerically studied. The failure modes observed in experiments are core shear failure and face-sheet/core debonding. A detailed model considering Nomex paper and resin coating is built with Abaqus/explicit simulation. The Hill 1948 quadratic anisotropic yield criteria are adopted to describe the plastic behavior of Nomex paper and the principal stress criteria are used for predicting the failure of resin coating. The effectiveness of the proposed meso-scale model is validated by comparing the experimental and the numerical results. The effects of geometric parameters on the bending behaviors are discussed in detail. It is shown that the ultimate force and bending stiffness of Nomex honeycomb sandwich panels is significantly influenced by the core orientation, resin thickness and cell size. The cutting position has no effect on the ultimate force and bending stiffness. [ABSTRACT FROM AUTHOR]

Surface acoustic wave spectroscopy has been established as non‐destructive and fast method for characterization of mechanical properties of surfaces and bulk materials in both research and industry. The present work shows that by application of a novel and robust aluminum nitride (AlN) coated piezoelectric contact sensor the advantages of the method can be extended from room temperature to at least 600°C. An overview of sensor concepts and applications of the method is discussed first, followed by theoretical and practical considerations for design and coating of a novel temperature stable contact sensor. After fabrication of such a sensor using magnetron sputtering, it was tested in a modified surface acoustic wave spectroscopy setup with an incorporated heating table concerning signal amplitude and frequency range. The AlN coated sensor was found to perform well up to 600°C, with temperature limited by the specification of the heating table. At room temperature, performance was acceptable when compared with a conventional contact sensor using a PVDF piezoelectric foil. Application of the high temperature capabilities of the setup was demonstrated by measuring temperature stability of hydrogen‐free amorphous carbon coatings (a‐C and ta‐C) depending on their sp3 carbon ratio. In another example, high precision temperature dependent measurement of Young's modulus for ultrasonic fatigue test specimen was taken, achieving an accuracy better than 1%. Use of the developed sensor opens up new possibilities in material science for in situ study of temperature depending mechanical properties for coatings and surfaces. [ABSTRACT FROM AUTHOR]