Coatings, Volume 14, Issue 5 (May 2024) – 71 articles

In this study, an Al₂O₃-40TiO₂ coating was deposited on 20MnNiMo steel via atmospheric plasma spraying. The corrosion behavior of the coating was investigated in both artificial seawater and a simulated environment with hydrogen sulfide and high pressure. Additionally, ion dissolution experiments were conducted to evaluate the coating’s bio-friendliness. In artificial seawater, the corrosion rate (based on the corrosion current) of the Al₂O₃-40TiO₂ coating initially decreased before increasing. It was speculated that the blocking of corrosion products in the defect channels was helpful in delaying the progress of corrosion in the early stage. The coating had a corrosion current on the order of 10⁻⁶ A/cm² in artificial seawater, suggesting good protection in conventional seawater environments. In the simulated environment, the corrosion rate (based on the weight loss) of the Al₂O₃-40TiO₂ coating showed a continuously declining trend. It was deduced that, unlike corrosion products in artificial seawater, the corrosion products in the simulated environment (e.g., metal sulfide) might be more chemically stable, leading to a longer blocking effect. Therefore, a minimal corrosion rate of 0.0030 mm/a was obtained after the coating was immersed for 30 days. The amount of dissolved coated elements was negligible and there were only small amounts of dissolved non-coated elements such as Ni and Mo. The developed coating can be considered to be highly biofriendly if the non-coated area of the specimen is well sealed. Full article

In this paper, a new consolidation material for earthen sites with silicone-modified acrylic emulsion was synthesized and applied to the consolidation test of soil samples of the site. The effectiveness was tested through the properties of soil samples on the changes in weight, color, permeability test, air permeability, hydrolysis resistance, water resistance, and salt resistance. The results show that the samples treated with the new material have an outstanding effect on hydrolysis resistance, water resistance, and salt resistance without the change in color and gas permeability. After being soaked in Na₂SO₄ and sodium chloride solution for half a month, the reinforced soil sample did not crack, and it could undergo 15 days of water resistance test and five cycles of sodium sulfate resistance. Full article

With the continuous exploitation of the marine resources, the equipment should meet the marine complex working environment. In this study, a type of environmentally friendly coating was prepared. Based on low surface energy environmental protection and anti-fouling, a film forming material with water-based epoxy-modified silicone resin emulsion was prepared. And industrial fillers were added to give it both inorganic and organic properties. Meanwhile, various contents of graphene oxide (GO) were added in the coating system. The coating properties were comprehensively analyzed, and the optimal GO content was obtained as 0.1 wt. %. The composite coating was studied by seawater immersion experiments, and the failure process of the coating in was proposed. The composite coating prepared in the present study has both environmental protection and hydrophobic anti-fouling characteristics, and its comprehensive performance is excellent through various performance evaluations, i.e., it meets the requirements of long-term coating, environmental friendliness and anti-fouling and corrosion resistance. Full article

Paints and coatings are widely used in various applications such as walls, cars, packaging, and food products. The quality of food packaging is essential due to its direct or indirect contact with food. The demand for high-quality food packaging is increasing due to the higher production and consumption rates. However, containers used in the beverage industry often face problems like scratches and abrasions during transportation. This study aimed to investigate different formulations of external coatings for beverage cans to improve their physical resistance properties and prevent corrosion and surface damage problems. The study involved reacting an acrylic resin with six different amino resins, including methylated melamine, butylated melamine, glycoluril, methylated urea, butylated urea, and benzoguanamine, in various proportions. The results of 25 formulated samples were compared based on properties such as adhesion, durability, and chemical resistance. The outcomes of the study showed significant differences among the crosslinking agents. Among all the crosslinking agents, methylated melamine showed the most favorable results in the analyses, proving to be effective in almost all tests. Full article

Nickel-element-doped zinc cobaltate/carbon fiber composites (Ni-ZnCo₂O₄/CF) were prepared on carbon cloth (made of a combination of carbon fibers) conductive substrates using a simple ambient stirring method combined with heat treatment. Characterization tests of the materials revealed that the prepared products were porous Ni-ZnCo₂O₄/CF mesh structures. This porous network structure increases the surface area of the material and helps shorten the diffusion path of ions and electrons. The samples were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) methods to investigate the effect of Ni elemental doping on the stability of the materials. The results show that there are no other impurity peaks and no other impurity elements in the Ni-ZnCo₂O₄/CF electrode material, which indicates that the sample purity is high. Meanwhile, the electrochemical properties of Ni-ZnCo₂O₄/CF electrode materials were studied. Under the condition of 15 A·g⁻¹, the specific capacitance of Ni-ZnCo₂O₄/CF electrode material is 1470 F·g⁻¹, and after 100 cycles, its specific capacity reaches 1456 F·g⁻¹, which is 99.0% of the specific capacity of 1470 F·g⁻¹, indicating that the electrode material has good stability. In addition, we assembled asymmetric supercapacitors (Ni-ZnCo₂O₄/CF//CNTs) with Ni-ZnCo₂O₄/CF as the positive material and carbon nanotubes (CNTs) as the negative material. In the cyclic stability experiment of Ni-ZnCo₂O₄/CF/CNTs devices, when the current density was 1 A·g⁻¹, the specific capacitance was 182 F·g⁻¹. After 10,000 cyclic charge–discharge tests, the specific capacity became 167 F·g⁻¹, which was basically unchanged compared with the initial specific capacity, reaching 91.8%. It shows that it has higher charge–discharge performance and higher cycle stability. Full article

Surface wear of the tap-changer contacts of industrial transformers (due to frequent switching times) easily leads to operation failure of industrial transformers, which affects the safety and stability of the transmission network. In this paper, an intelligent voice signal monitoring system was proposed for the abnormal condition (surface wear) of tap-changer contacts. This monitoring system was composed of a voice signal acquisition system, voice analysis system and voice processing system. First, the voice signal of the tap-changer contacts was collected, and the collected voice signal was analyzed in the time domain and the frequency domain. Secondly, the characteristic curve of the voice signal was proposed, and the voice curve was compared with that of the normal operation state. In this case, the running state and surface wear abnormal situation of the tap changer could be monitored and determined, and the cause of the abnormal state could also be further analyzed. This method solved the surface wear problem of the tap changer in industrial transformers, which could be not monitored effectively in real time. This method improved the operational reliability of industrial transformers and had high economic and social benefits. Full article

In order to clarify the mechanical response of permeable asphalt pavements under a temperature effect, the mechanical responses of different types of permeable asphalt pavements, which were based on a self-developed drainage SBS-modified asphalt mixture with fiber, were simulated using ANSYS finite element software(APDL 19.2). The influence of temperature and temperature change on the mechanical behavior of the permeable asphalt pavements was studied, and the mechanical responses of the pavements at different driving speeds was analyzed. The results show that the extreme values of surface deflection, compressive strain of the soil foundation top surface, and the shear stress and tensile stress of the upper-layer bottom of the three kinds of pavements under dynamic load were about 10% smaller than those under static loads, and the extreme values under different temperature conditions were 28%~50% larger than the values obtained without different temperature conditions. During the 12 h heating process, the mechanical indexes of the three types of pavements with axle loads were consistent with the change law of temperature, and the peak values of the mechanical indexes under dynamic loads were smaller than those under static loads. In addition, the mechanical indexes of the three types of pavements under dynamic loads had the same law of change with speed under the same conditions, and the values were less than the extreme values under static loads, but the degree of influence was different. Full article

Nb₃Sn is emerging as one of the focal points in superconducting radio frequency (SRF) research, owing to its excellent superconducting properties. These properties hold significant possibilities for cost reduction and the miniaturization of accelerators. In this paper, we report the recent efforts of the Shanghai Advanced Research Institute (SARI) in fabricating high-performance Nb₃Sn superconducting cavities using the vapor diffusion method. This includes the construction of a Nb₃Sn coating system with dual evaporators and the test results of 1.3 GHz single-cell coated cavities. The coated samples were characterized, and the growth state of the Nb₃Sn films was analyzed. The first coated superconducting cavity was tested at both 4.4 K and 2 K, with different cooldown rates passing through the Nb₃Sn critical temperatures. The causes of Sn droplet spot defect formation on the surface of the first cavity were analyzed, and such defects were eliminated in the coating of the second cavity by controlling the evaporation rate. This study provides a reference for the preparation of high-performance Nb₃Sn-coated cavities using the vapor diffusion method, including the setup of the coating system, the comprehension of the vapor diffusion process, and the test conditions. Full article

Regenerated water serves as a supplementary source for circulating cooling water systems, but it often fosters microbial growth within pipelines. Given its widespread use as a corrosion inhibitor, understanding HEDP’s efficacy in microbial environments and its impact on microorganisms is imperative. This study established an iron bacterial system by isolating and enriching iron bacteria. Through a comprehensive approach incorporating corrosion weight loss analysis, XPS analysis, SEM electron microscopy, as well as microbial and electrochemical testing, the corrosion inhibition behavior and mechanism of HEDP within the iron bacterial system were investigated. The findings reveal that within the iron bacterial system, HEDP achieves a corrosion inhibition rate of 76% following four distinct stages—weakening, strengthening, stabilizing, and further strengthening—underscoring its robust corrosion inhibition capability. Moreover, HEDP enhances the density of biofilms and elevates the activation energy of carbon steel interfaces. It alternates with oxygen to continuously suppress the activity of IRB while gradually inhibiting the activity of IOB. This process culminates in a corrosion inhibition mechanism where cathodic inhibition predominates, supported by anodic inhibition as a complementary mechanism. Full article

Surface treatment technologies are pivotal across diverse industrial sectors such as mechanical engineering, electrical engineering, and the automotive industry. Continuous advancements in manufacturing processes are geared towards bolstering efficiency and attaining superior product quality. This study aimed to empirically compare practical outcomes with theoretical insights. Employing galvanic zinc plating under constant voltage with varying plating durations unveiled a correlation between coating thickness and electrolyte composition alongside plating duration. The graphical representation delineated the optimal electrolyte composition conducive to maximal coating thickness. Notably, an evident decrease in leveling ability was noted with prolonged plating durations. The experiment corroborated the notion that theoretical formulas for coating thickness estimation possess limited accuracy, often resulting in measured values surpassing theoretical predictions. These findings underscore the imperative for refined theoretical models to comprehensively grasp galvanic surface treatment processes. Full article

This study investigates the impact of vapour-phase precursor flow rates—specifically those of trimethylaluminum (TMA) and deionized water (H₂O)—on the deposition of aluminum oxide (Al₂O₃) thin films through atomic layer deposition (ALD). It explores how these flow rates influence film growth kinetics and surface reactions, which are critical components of the ALD process. The research combines experimental techniques with a zero-dimensional theoretical model, designed specifically to simulate the deposition dynamics. This model integrates factors such as surface reactions and gas partial pressures within the ALD chamber. Experimentally, Al₂O₃ films were deposited at varied TMA and H₂O flow rates, with system conductance guiding these rates across different temperature settings. Film properties were rigorously assessed using optical reflectance methods and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. The experimental findings revealed a pronounced correlation between precursor flow rates and film growth. Specifically, at 150 °C, film thickness reached saturation at a TMA flow rate of 60 sccm, while at 200 °C, thickness peaked and then declined with increasing TMA flow above this rate. Notably, higher temperatures generally resulted in thinner films due to increased desorption rates, whereas higher water flow rates consistently produced thicker films, emphasizing the critical role of water vapour in facilitating surface reactions. This integrative approach not only deepens the understanding of deposition mechanics, particularly highlighting how variations in precursor flow rates distinctly affect the process, but also significantly advances operational parameters for ALD. These insights are invaluable for enhancing the application of ALD technologies across diverse sectors, including microelectronics, photovoltaics, and biomedical coatings, effectively bridging the gap between theoretical predictions and empirical results. Full article

The low toughness of epoxy resin can influence its shielding performance against a corrosive medium and strength of adhesion to metal surfaces. Extensive efforts have been made to modify epoxy resin. In this research, acrylic resin was synthesized by the solution method, and 1 wt.%, 2.5 wt.%, and 5 wt.% were added to epoxy resin (E44 brand) to prepare coatings on the surface of AZ31B magnesium alloy. The effects of acrylic resin on the mechanical and protective properties of epoxy coatings were investigated via experiments measuring impact resistance, flexibility, and adhesion as well as the electrochemical impedance technique. Compared with the pure epoxy coating, the adhesion between the coating and the substrate increases by 1.37 MPa after the addition of 2.5 wt.% acrylic resin. Meanwhile, the pencil hardness has a slight change from 5B to 6B, and the flexibility significantly improves. Therefore, the epoxy coating exhibits enhanced anticorrosive properties after the addition of 2.5 wt.% acrylic resin. Full article

The paper breaks the general concepts and shows that pore formation is possible in anodic aluminum barrier oxide by anodizing of pure Al, and also presents the results of electrochemical anodizing in boric acid and citrate buffer aqueous solutions of homogeneous binary alloys AlCu (4 wt.%), AlZn (3 wt.%) and AlAg (5.2 wt.% and 16.2 wt.%). Barrier anodizing allowed obtaining Al₂O₃ thin films doped with copper, zinc and silver. The anodizing behavior and the effect of anodic current density on the charge were studied, and scanning electron microscopy, X-ray photoelectron spectroscopy and Auger electron spectroscopy analyses were performed. The doped alumina thin films, which are a mixture of Al₂O₃, Cu₂O, ZnO, Ag₂O, AgO and promising double metal oxides CuAlO₂, AgAlO₂ and ZnAl₂O₄, are promising for use as resistive switching, photoelectron, mechanical, photo-thermoelectric and fluorescence materials; sensors; and transparent conductive and photocatalyst films. Full article

G115 steel is a novel martensitic heat-resistant steel, primarily utilized in the main steam pipelines and collectors of ultra-supercritical thermal power units. However, the oxidation resistance of martensitic steels in the high-temperature steam environment is usually suboptimal, significantly affecting the efficiency of power plants. In this paper, shot peening (SP) is employed as a surface treatment method for G115 steel, and the oxidation kinetics, oxide layer thickness, and microstructure of shot-peened G115 samples are compared with those of G115 steel. The results indicate that in the 650 °C steam environment, the oxidation kinetics of the shot-peened samples follow the parabolic law and that the oxidation weight gain is significantly smaller than that of the non-shot-peened samples. The higher the SP intensity, the smaller the oxidation weight gain and the better the oxidation resistance. This can be attributed to the fragmentation of the grains in the surface layer caused by external stress during SP, which creates a multitude of grain boundaries that can provide rapid diffusion pathways for corrosion-resistant Cr atoms, resulting in the accelerated outward diffusion of Cr atoms from the substrate. Simultaneously, a continuous and dense FeCr₂O₄ protective layer is produced at the interface between the SP layer and the substrate, obstructing the inward diffusion of oxygen and enhancing the oxidation resistance of G115 steel. Full article

Expanded polystyrene (EPS) particles are commonly used for thermal insulation in lightweight building materials due to their low density, low thermal conductivity, and affordability. However, shortcomings such as hydrophobicity and poor fire safety limit the application of EPS. Bio-based flame retardants have been developed for use in polymer composites due to their renewable, environmentally friendly, and non-toxic properties. In this study, to improve the hydrophilicity and fire resistance of EPS particles, phytic acid (PA)/chitosan (CS)–polydopamine (PDA)@EPS particles (PA/CS-PDA@EPS) with a bio-based coating were prepared by using a simple coating method based on PDA@EPS particles using PDA as an adhesive and PA and CS as bio-based flame retardants. The results showed that the modified EPS particles had good hydrophilicity, the residual carbon yield of the 10PA/3CS-PDA@EPS samples was increased to 24 wt%, and the maximum loss rate was reduced by 69% compared with unmodified EPS. In flammability tests, the 10PA/3CS-PDA@EPS samples also demonstrated low flame spread and some fire resistance. Furthermore, the modified EPS particles exhibited fire resistance even after multiple washings. The hydrophilic and fire-resistant modified EPS particles are anticipated to offer a novel approach to the advancement of EPS-based lightweight building materials. Full article

Full-depth reclamation with Portland cement (FDR-PC) represents an innovative cold recycling technology for pavements, holding significant promise due to its capacity to reuse deteriorated pavement base layers. This paper investigates the key factors influencing the strength properties of FDR-PC. The results indicate that, compared to the static compaction method, the vibratory compaction method yields cold-recycled mixtures with higher maximum dry density and unconfined compressive strength (UCS). Increasing the cement content and base-to-surface ratio, extending the curing time, and raising the curing temperature all contribute to enhancing UCS. Furthermore, increasing the base-to-surface ratio and cement content enhances both indirect tensile strength and flexural strength. An approximate linear correlation exists between indirect tensile strength and UCS, as well as between flexural strength and UCS. The strength characteristics of FDR-PC were comprehensively characterized in this study, providing effective verification of its applicability. Full article

Heat treatment plays a decisive role in the microstructure of metallic materials. The effect of cooling rate changes caused by the quenching medium on the microstructure of steel materials should be clarified. In this study, the effect of the quenching cooling rate on the microstructure of two precipitation-hardened martensitic stainless steels was investigated. The mechanical properties and hydrogen embrittlement susceptibility effected by the changes in the microstructure were also analyzed. A slow tensile test and hydrogen pre-charging were carried out to obtain the hydrogen embrittlement susceptibility parameters of the specimens. The results show that the quenching cooling rate only affects specific microstructures, including the twin structure and misorientation angle. Before hydrogen charging, the mechanical properties of the precipitation-hardened martensitic stainless steels were not affected by changing the quenching cooling rate. After hydrogen charging, the hydrogen embrittlement susceptibility decreased as the quenching cooling rate increased. Full article

Titanium and its alloys have been widely employed as dental implant materials. However, polymicrobial infection is still one of the most common reasons for implant failure, which has already become a worldwide problem and poses a threat to human health. In this study, a titanium-based (Ti-based) superhydrophobic coating was effectively created by anodization followed by hydrophobic modification of 1H,1H,2H,2H-perfluorodecyltriethoxysilane (FAS), which shows a high water contact angle (WCA) of 159.9 ± 5.8° and a low water sliding angle (WSA) of 2.7 ± 2.2°. The thickness of the anodized samples is from 500 nm to 4 µm as the anodizing voltage increases. The Ti-based superhydrophobic coating demonstrated the existence of Ti, O, C, F, and Si elements, and the corresponding phase compositions are Ti and anatase. The results showed that the Ti-based superhydrophobic coating has good biocompatibility to co-culture with L929 cells for 1, 3, and 5 days. It was also proven that the as-prepared Ti-based superhydrophobic coating has enhanced antibacterial abilities against Staphylococcus aureus (S. aureus) and Porphyromonas gingivalis (P. gingivalis, P.g) after 4, 12, and 24 h. Moreover, the Ti-based superhydrophobic coating can significantly reduce platelet adhesion and activation. In addition, the Ti-based superhydrophobic coating also exhibits a considerable positive shift in the corrosion potential (E_corr) and a decline of one order of magnitude in the corrosion current density (J_corr), showing good anticorrosive properties. It was also found that the capsule around the Ti-based superhydrophobic coating was thinner than that of bare Ti after implantation for 7, 15, and 28 days, indicating its good biosafety. Therefore, the as-prepared Ti-based superhydrophobic coating can be a suitable candidate for Ti-based implants in dental applications. Full article

Controlling cell adhesion, viability, and proliferation on solid surfaces is critical for the successful implantation and proper functioning of temporary and permanent medical devices. While, with temporary or removable implants as well as surgical instruments, even slight cellular adhesion leads to an increased risk of secondary infections, bleeding and other complications, good cellular adhesion and viability are essential for the rapid healing and successful integration of permanent implants. This work was motivated by the growing interest in the construction of biocompatible and biodegradable coatings for the biofunctionalization of medical devices. Polysaccharide-based coatings are well known for their biocompatibility, but they are non-cell-adhesive, which hinders their application as implant coatings. In this study, we demonstrate that the incorporation of one or more graphene oxide layers in hyaluronic acid/chitosan multilayers is one avenue to regulate the degree of unspecific adhesion and growth of different cells (human umbilical vein endothelial cells, HUVEC, and mouse embryonic fibroblasts, 3T3). Furthermore, we demonstrate that this approach allows cell adhesion to be regulated across the entire range between completely prevented and highly promoted cell adhesion without introducing systemic cytotoxicity. These findings may contribute to the establishment of a new approach to adapt medical devices to cells and tissues. Full article

Corrosion and friction coefficient tests were performed on solid oak wood machined with hard-metal woodworking tools coated with PVD coatings (AlCrN, AlTiN, TiAlN, TiCN and CrN). The tannic acid attacks the carbide more intensively than the PVD coatings. During cutting, corrosion spreads on the cutting edge of the cutter due to mechanical action, which dissolves the cobalt binder of the hard-metal and causes the carbide grains to flake off. After 80 min of contact with the wood, the cobalt content decreases from 3.53 to 1.74%. Depending on the PVD coating material, cracks of 4 to 40 µm in width appear after 120 min (9000 m cutting path). After 120 min of machining, wear, corrosion effects and the influence of corrosion on the coefficients of friction were evaluated for tools with and without PVD coatings. TiCN is the most sensitive to corrosion, while AlCrN and CrN coatings are the least sensitive, with the AlTiN coating being the most affected under real cutting conditions (with mechanical + thermal + corrosion effects) and the tools with CrN and AlCrN coatings being the least affected. Corrosion affects the hard-metal and PVD coatings and reduces the coefficient of friction. The angle between the directions of sliding and sharpening of the cutting edge sharpening significantly influences this parameter. The coefficient of friction of hard-metal WC-Co and PVD coatings is higher in the parallel machining direction than in the perpendicular machining direction and ranges from 16.03% (WC-Co) to 44.8% (AlTiN). The coefficient of friction of hard-metal WC-Co decreases by 5.13% before and after exposure to tannic acid, while the corrosion of PVD coatings reduces it by 4.13% (CrN) to 26.7% (TiAlN). Full article

Public awareness of preventing pathogenic microorganisms has significantly increased. Among numerous microbial prevention methods, the deep-ultraviolet (DUV) disinfection technology has received wide attention by using the nitride-based light-emitting diode (LED). However, the light extraction efficiency of DUV LEDs and the utilization rate of emitted DUV light are relatively low at the current stage. In this study, a light distribution design (referred to as the reflective system) was explored to enhance the utilization of emitted DUV from LEDs, leading to successful and efficient surface and air disinfection. Optical power measurements and microbial inactivation tests demonstrated an approximately 79% improvement in average radiation power density achieved by the reflective system when measured at a 5 cm distance from the irradiation surface. Moreover, a statistically significant enhancement in local surface disinfection was observed with low electric power consumption. The reflective system was integrated into an air purifier and underwent air disinfection testing, effectively disinfecting a 3 m³ space within ten minutes. Additionally, a fluorine resin film at the nanolevel was developed to protect the light module from oxidation, validated through a 1200 h accelerated aging test under humid conditions. This research offers valuable guidance for efficient and energy-saving DUV disinfection applications. Full article

The complex red-bed geology is primarily composed of iron-rich sedimentary rock layers with clay minerals as a major component. The soil water content exceeds 30%, and its high viscosity and water content lead to the easy formation of mud cake on the cutterhead, endangering the safety and progress of construction, which poses a significant challenge for tunnel boring machines (TBMs). The use of dispersants to eliminate mud cake is a common method in engineering projects. This paper presents an improved disintegration experiment instrument to study the disintegration characteristics of mud cake from the red-bed geology under different dispersant solutions, proposing a dispersant formulation suitable for the red-bed geology of the Haizhu Bay Tunnel project. The results indicate that mud cake samples exhibit a moderate disintegration effect in pure water. Furthermore, it has been observed that the disintegration effect decreases as the thickness of mud cake increases. Sodium silicate solution was not suitable for treating the red-bed geological mud cake, while sodium hexametaphosphate and oxalic acid solutions had a good promoting effect on the disintegration of red-bed geological mud cake. However, there was a threshold for the dispersant concentration; exceeding this threshold actually worsened the disintegration effect. Ultimately, the engineering application of a 10% oxalic acid solution, which proved effective in disintegrating the mud cake, significantly enhanced the excavation efficiency in the Haizhu Bay Tunnel project. Full article

Traditional roadway lighting is intended to provide safe guidance for drivers and pedestrians, but the large-scale application of roadway lighting has resulted in significant energy consumption and light pollution. However, road markings prepared by luminous coating are a kind of multi-functional road marking that can meet the needs of highway lighting at night and save energy. Here, CaAl₂O₄:Eu²⁺,Nd³⁺,Gd³⁺ blue long-afterglow phosphor is obtained by the high-temperature solid-state method, and the blue luminescent coating is synthesized by the blending method. The phase composition, microscopic morphology, luminescence properties and water resistance of the phosphor and luminescent coatings are characterized. The best components and processes of the luminescent coating are explored to meet the application of an expressway. Considering the afterglow’s performance, the optimal calcination temperature of the phosphor is determined to be 1300 °C. The afterglow of the phosphor can be over 8 h after 2 h of daylight excitation. The addition of 1.25% SiO₂ to the luminescent coating improves the uniformity of the components, and the incorporation of 3.5% CaCO₃ improves the denseness of the coating. When the coating thickness is 0.8mm, the luminescent coating can achieve the best luminous effect. After 120 h of immersion in water, the afterglow intensity of the luminescent coating reduced to 70% of the original, which has excellent water resistance. The blue luminescent coating with the addition of appropriate amounts of CaCO₃ and SiO₂ improves the dispersion as well as the densification of the components in the coating to achieve the best luminescent effect. In the Shenyang area, different weather conditions (cloudy, sunny, rainy) have no significant effect on the afterglow performance of the luminescent coatings, all of which can achieve over 5 h of afterglow and are suitable for expressways. Full article

Ti–Ta impedance-graded coatings were prepared using cold spraying combined with hot isostatic pressing. Compared to the general Ti–Ta binary diffusion couple, the interdiffusion coefficient of as-sprayed Ti–Ta can be increased by approximately 25 times at 1100 °C due to grain refinement at the interface of the cold-sprayed particles. By the control of interdiffusion, pure Ta and pure Ti regions can remain in the materials after hot isostatic pressing at 900 °C. Hot isostatic pressing with capsulate reduced the porosity of the material efficiently to less than 0.02%. The strength of the as-sprayed Ti–Ta composite coating was significantly improved to 990.1 MPa, and the fracture strain reached 11.5%. The strengthening mechanism of Ti–Ta composite coatings relies primarily on the hindrance of dislocation slip by phase interfaces between α and β. Moreover, the macroscopic interfacial bonding strength of the graded material exceeds 881 MPa, which is comparable to that of bulk materials. Full article

In order to improve the pseudocapacitance performance of metal sulfide electrode materials and obtain supercapacitor energy storage devices with excellent electrochemical reversibility and long-term cycle stability, the synthesis of flower-shaped crystal nickel–cobalt sulfide and its supercapacitor performance were studied. NiCo₂S₄ flower-shaped crystal nickel–cobalt sulfide was prepared by the hydrothermal method with nickel foam as the raw material, and electrode materials were added to prepare supercapacitor electrodes for testing of the supercapacitor performance. The physical properties of flower-shaped crystal nickel–cobalt sulfide were tested by a scanning electron microscope and transmission electron microscope, and the voltammetric cycle and constant current charge and discharge of supercapacitor electrodes prepared from this sulfide were analyzed through experiments. The experimental results showed that the flower crystal microstructure had a positive effect on the electrochemical properties. The capacitance value was always high at different current densities, and the capacity was as high as 3867.8 A/g at pH 12. After 2000 voltage–charge–discharge cycle tests, the petal-like sulfide capacity still had a retention rate of 90.57, the flower crystal nickel–cobalt sulfide still showed an excellent supercapacitor performance and the specific capacity was still high, which demonstrates that this sulfide has excellent cyclic stability and durability in electrochemical applications. Full article

Electrospark coatings alloyed with MoS₂ have been studied. The coatings were obtained by the following two strategies: the first consisted of pre-applying molybdenum disulfide to the treated surface and alloying with a molybdenum electrode (Mo + MoS₂ coating); the second consisted of applying a paste with a sulfur content of 33.3% to the treated surface and alloying with a molybdenum electrode (Mo + S coating). The structure, phase composition, and tribological properties of the coatings were investigated. The coatings have a complex structure consisting of an upper soft layer, a hardened white layer, a diffusion zone, and a substrate. Element analysis and cross-sectional hardness changes indicated that element diffusion occurred at the coating/substrate interface. The phase composition of the coatings is represented by BCC and FCC solid solutions on Fe, and MoS₂ is also detected. In Mo + S coatings, the molybdenum disulfide on the surface is about 8%; in Mo + MoS₂ coatings, it is 27%–46%. The obtained coatings show very good tribological properties compared to molybdenum ESA coatings. The frictional forces and coefficients are reduced by a factor of 10 and 40, depending on the test conditions. Full article

With the development of society, the demand for smart coatings is increasing. The development of flexible strain sensors using block copolymer self-assembled ionic gel materials provides a promising method for promoting the development of smart coatings. The ionic liquid in the ionic part of the material is crucial for the performance of the sensor. In this study, the structural changes within FDA/dEAN (self-assembly of acrylated Pluronic F127 (F127-DA) in partially deuterated ethylammonium nitrate (dEAN)) triblock copolymer ionic gel during uniaxial tensile flow were characterized using an in situ SAXS technique. The results revealed that the characteristics of the responses of the ionic gel to strain resistance were intricately linked to the evolution of its microstructure during the tensile process. At low levels of strain, the face-centered cubic lattice arrangement of the micelles tended to remain unchanged. However, when subjected to higher strains, the molecular chains aligned along the stretching direction, resulting in a more ordered structure with reduced entropy. This alignment led to significant disruption in bridging structures within the material. Furthermore, this research explored the impact of the stretching rate on the relaxation process. It was observed that higher stretching rates led to decreases in the average relaxation time, indicating rate dependence in the microstructure’s behavior. These findings provide valuable insights into the behavior and performance of flexible strain sensors based on ionic gel materials in smart coatings. Full article

The frictional properties of lithium compound grease (LCG) with different percentage compositions of few-layer graphene (FLG) were investigated, and the mechanisms of temperature and loading effects on LCG containing FLG are also considered. The concluding effect shows that 1 wt% FLG is more appropriate for friction and wear modifiers for lithium compound grease at elevated temperatures and less suitable at ordinary temperatures. Thickener chemisorption film, FLG layering film, and tribo-reaction film consisting of FeO(OH), Fe₂O₃, Fe₃O₄, Li₂O, and other oxides assist in the establishment of a lubricating boundary film on the friction interfaces lubricated with LCG containing FLG. The poor fluidity of lithium compound grease at low temperatures leads to poor dispersion of FLG, decreasing friction reduction capability. Under elevated temperature and low load condition, adding 1wt% FLG to LCG can only improve its wear-resistant property, the abrasion volume of steel plate reduced by 24.49%. Under elevated temperature and high load condition, adding 1wt% FLG to LCG can only enhance its anti-friction characteristics. Conversely, FLG is unsuitable as an anti-friction and wear-resistant additive for LCG at low-temperature conditions. Full article

Since it is difficult to study the influence of different defect characteristics on the stress intensity factor of B-type sleeve fillet welds via experiments, this paper adopts ABAQUS finite element analysis software(Version 2019) to model the B-type sleeve fillet welds and studies the stress and stress intensity factor under different crack lengths, heights, and angles. The simulation results showed that with the increase in crack length and depth, the maximum stress intensity factor gradually increased, and with the increase in the crack inclination angle, the maximum stress intensity factor first increased and then decreased. Full article

Anyuan Temple, constructed in the 29th year of the Qing Dynasty (1764), serves as a repository of numerous Sanskrit inscriptions and Hexi color paintings from the Qing era. Among its collections, the green Tara Buddha statue, exquisitely carved from wood, is recognized as a national first-class cultural relic. This edifice is instrumental in advancing our comprehension of painting artistry in royal temples. The current research focused on the pigments and binders utilized in the color paintings within Anyuan Temple, located in Chengde. An investigative process entailed collecting four samples from the paintings adorning the temple’s beams. These samples underwent comprehensive analysis using a variety of techniques, such as Scanning Electron Microscopy and Energy-Dispersive Spectrometry (EDS), Micro Raman Spectroscopy (m-RS), and X-ray Diffraction (XRD). The examination revealed that the paintings comprised pigments of lead white, cinnabar, malachite, and azurite, corresponding to the colors white, red, green, and blue, respectively. The enduring stability and aesthetic appeal of these pigments suggest their suitability for use in future conservation efforts. Additionally, Pyrolysis Gas Chromatography/Mass Spectrometry (Py-GC/MS) analysis identified animal glue as the binding agent in the wood component paintings. These insights are pivotal for the forthcoming restoration endeavors of Anyuan Temple, offering essential guidance in selecting the appropriate materials for restoration. Full article