Coatings

44 pages, 3411 KB

Open AccessReview

A Review of Residual Stress and Deformation in Metal Additive Manufacturing: Formation Mechanisms, Influencing Factors, Prediction Methods, and Mitigation Strategies

by Yongsheng Li, Jiahao Yan, Min Wen, Guanglei Liu and Dingding Xiang

Coatings 2026, 16(8), 975; https://doi.org/10.3390/coatings16080975 (registering DOI) - 16 Aug 2026

Abstract

Metal additive manufacturing (MAM) enables the fabrication of geometrically complex and high-performance components but is accompanied by steep thermal gradients, repeated thermal cycling, phase transformation, residual stress, and deformation. These effects can reduce dimensional accuracy, manufacturing stability, fatigue resistance, and service reliability. This [...] Read more.

Metal additive manufacturing (MAM) enables the fabrication of geometrically complex and high-performance components but is accompanied by steep thermal gradients, repeated thermal cycling, phase transformation, residual stress, and deformation. These effects can reduce dimensional accuracy, manufacturing stability, fatigue resistance, and service reliability. This review systematically examines residual-stress and deformation behavior in MAM from the perspectives of formation mechanisms, influencing factors, measurement and prediction methods, mitigation strategies, and service-related consequences. The temperature gradient, mechanical constraint, and phase transition mechanisms are discussed as quantitatively coupled rather than independent processes. Comparative attention is given to process-specific differences, alloy-dependent thermophysical and metallurgical behavior, multi-track and multi-material interactions, and complex geometries. Destructive and non-destructive measurement techniques are compared in terms of penetration depth, spatial resolution, uncertainty, and cross-validation. Thermo-mechanical finite element, inherent strain, analytical, reduced-order, machine-learning, physics-informed, and digital-twin approaches are evaluated according to accuracy, efficiency, transferability, and applicability. Mitigation strategies are further compared considering residual-stress reduction, deformation control, manufacturing cost, and mechanical-property retention. Finally, challenges associated with uncertainty quantification, service environments, post-machining stress redistribution, and closed-loop control are identified. This review provides an integrated framework for selecting measurement, prediction, and mitigation approaches for reliable and high-precision MAM. Full article

(This article belongs to the Topic Microstructure and Properties in Metals and Alloys, 4th Edition)

13 pages, 6572 KB

Open AccessArticle

Fabrication and Characterization of Ti-Nb Coatings by an Electron-Beam Surface Alloying

by Ivana Ilievska, Fatme Padikova, Georgi Kotlarski, Edmon Lazarov, Borislav Stoyanov, Lyubomira Veleva, Angel Anchev, Maria Ormanova and Stefan Valkov

Coatings 2026, 16(8), 974; https://doi.org/10.3390/coatings16080974 (registering DOI) - 16 Aug 2026

Abstract

Ti–Nb alloys are widely recognized as highly promising materials for orthodontic applications due to their excellent functional properties, including superior biocompatibility and a relatively low Young’s modulus that better matches that of human bone. The formation of Ti–Nb surface alloys or surface-modified layers [...] Read more.

Ti–Nb alloys are widely recognized as highly promising materials for orthodontic applications due to their excellent functional properties, including superior biocompatibility and a relatively low Young’s modulus that better matches that of human bone. The formation of Ti–Nb surface alloys or surface-modified layers is particularly attractive, as the surface properties of biomedical materials strongly influence their mechanical and biological interactions during service. In the present study, Ti-Nb coatings were fabricated on commercially pure titanium substrates using an electron beam surface treatment (EBST) technique. Initially, a 1 μm thick Nb layer was deposited onto the Ti substrates by direct current (DC) magnetron sputtering. Subsequently, the samples were modified through scanning electron beam irradiation, with beam power varied between 1000 and 2000 W to promote Ti-Nb alloyed layers. The phase composition of the resulting structures was analyzed by X-ray diffraction (XRD). Microstructural characteristics and chemical composition were examined using scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS). Mechanical properties were evaluated in terms of hardness and Young’s modulus. The findings of this study demonstrate the feasibility of tailoring the structural and mechanical properties of Ti–Nb surface alloys through controlled electron-beam processing and support their further investigation for potential orthodontic and dental applications. Full article

(This article belongs to the Special Issue Surface Engineering and Characterization of Bioactive Coatings for Biomedical Applications)

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22 pages, 18946 KB

Open AccessArticle

A Novel Slippery Liquid-like Icephobic Surface Coating for Unmanned-Aerial-Vehicle Propeller Icing Protection

by Jincheng Wang, Carlos Valentin, Kayde Bowers, Lingxuan Hao, Bei Fan and Hui Hu

Coatings 2026, 16(8), 973; https://doi.org/10.3390/coatings16080973 (registering DOI) - 16 Aug 2026

Abstract

Freezing rain poses a substantial hazard to the operation and safety of unmanned aerial vehicles (UAVs) in cold-weather environments. In the present study, a comprehensive experimental campaign was conducted to investigate the effect of surface icephobicity on ice accretion and shedding from rotating [...] Read more.

Freezing rain poses a substantial hazard to the operation and safety of unmanned aerial vehicles (UAVs) in cold-weather environments. In the present study, a comprehensive experimental campaign was conducted to investigate the effect of surface icephobicity on ice accretion and shedding from rotating UAV propellers under freezing-rain conditions. A novel, durable, slippery liquid-like surface (SLLS) coating, characterized by low contact-angle hysteresis and low ice adhesion, is utilized as a passive strategy for UAV icing mitigation. The coating was assessed through wettability and ice-adhesion measurements, phase-locked high-speed imaging of supercooled large-droplet impingements, rotating-propeller ice accretion experiments, accelerated rain erosion testing, and surface-topography characterization. The measurement results revealed distinct normal and oblique droplet impingement regimes and demonstrated that the evolving leading-edge ice geometry substantially altered droplet deformation, liquid redistribution, and subsequent ice growth. Compared with the uncoated, baseline propeller, the SLLS-coated propeller was found to promote earlier ice shedding and reduce the ice-induced power consumption by approximately 36%. These findings highlight the potential of SLLS coatings as a promising strategy for UAV propeller icing protection to ensure safer and more efficient UAV operations under adverse weather conditions. Full article

(This article belongs to the Special Issue Recent Advances in Superhydrophobic and Icephobic Surfaces, Second Edition)

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25 pages, 5150 KB

Open AccessArticle

Effects of Laser Conditioning on the Removal of Surface Nanoparticle Defects and the Damage Threshold of Optical Coatings

by Jinlong Zhang, Zhenyin Lu, Dianhao Dong, Shuai Jiao, Dongyue Yan, Dongdong Li and Shenghuan Fang

Coatings 2026, 16(8), 972; https://doi.org/10.3390/coatings16080972 (registering DOI) - 16 Aug 2026

Abstract

Surface nanoparticle defects are among the key factors that reduce the laser-induced damage threshold (LIDT) of high-power laser coatings. In this study, the effects of nanosecond laser conditioning and continuous-wave laser conditioning on the removal of surface nanoparticle defects with different sizes and [...] Read more.

Surface nanoparticle defects are among the key factors that reduce the laser-induced damage threshold (LIDT) of high-power laser coatings. In this study, the effects of nanosecond laser conditioning and continuous-wave laser conditioning on the removal of surface nanoparticle defects with different sizes and material compositions, as well as on the LIDT of SiO₂ coatings, were systematically investigated. The results show that laser conditioning can reduce the number density of surface particles and improve the LIDT of the coatings under appropriate conditions. Under nanosecond laser conditioning, particle detachment is mainly attributed to the inertial effect induced by rapid transient thermal expansion. In contrast, under continuous-wave laser conditioning, particle detachment is primarily governed by interfacial instability induced by thermal expansion mismatch between the particles and the coating. This study provides experimental evidence and clarifies the dominant surface particle-detachment mechanisms under nanosecond and continuous-wave laser conditioning in optical materials, and offers a useful reference for the fabrication of optical coatings with high laser damage thresholds. Full article

(This article belongs to the Section High-Energy Beam Surface Engineering and Coatings)

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34 pages, 14954 KB

Open AccessArticle

Rheological Properties and Microstructure of Waterborne Epoxy Resin Modified Emulsified Asphalt

by Wei Zhang, Shi Hu, Shuai Zhang, Qin Liu, Yihan Shi and Jian Ouyang

Coatings 2026, 16(8), 971; https://doi.org/10.3390/coatings16080971 (registering DOI) - 15 Aug 2026

Abstract

As a road repair material, emulsified asphalt offers advantages such as convenient construction, good fluidity, and environmental safety. However, its relatively low strength limits its application range, making performance enhancement a key research focus. In this study, waterborne epoxy resin (WER) was used [...] Read more.

As a road repair material, emulsified asphalt offers advantages such as convenient construction, good fluidity, and environmental safety. However, its relatively low strength limits its application range, making performance enhancement a key research focus. In this study, waterborne epoxy resin (WER) was used to modify emulsified asphalt, and the preparation process and performance were systematically investigated. Three types of waterborne epoxy systems were selected, and through compatibility, film-forming performance, and bonding strength tests, the JT waterborne epoxy system was identified as having the best overall performance, with an optimal epoxy-to-curing-agent ratio of 1:0.6. Modified emulsified asphalts with different proportions of WER and styrene–butadiene rubber were prepared. Using fluorescence microscopy, image recognition techniques, and multiple experimental evaluations, the distribution of epoxy resin in the emulsified asphalt was quantitatively analyzed. The results show that the addition of WER significantly improves the bonding strength of emulsified asphalt, with the fastest rate of increase observed in the 5−10% range. However, a comprehensive evaluation considering microstructure uniformity, rheological performance, and water resistance indicates that the optimal overall performance is achieved in the 10−12% range, and the WER content should strictly be controlled below 15% to avoid severe local agglomeration. Meanwhile, the modified water-boiling test reveals that the adhesion between WERAE and aggregates is significantly enhanced, implying a potentially improved resistance to moisture-induced damage under practical service conditions. The standard deviation of area results indicate that when the WER content exceeds 15%, local agglomeration occurs, which is unfavorable for strength development of the modified system; the distribution uniformity results further show that when the WER content is greater than 12%, it negatively affects the uniform dispersion of WER within the emulsified asphalt. Full article

(This article belongs to the Special Issue Advances in Asphalt and Concrete Coatings)

12 pages, 3676 KB

Open AccessArticle

Processing and Tribological Behavior of Graphene Oxide Nanoplates Reinforced UHMWPE Composites

by Yang Liu, Jing Li, Kaibao Wang and Huirong Le

Coatings 2026, 16(8), 970; https://doi.org/10.3390/coatings16080970 - 14 Aug 2026

Abstract

Ultra-high molecular weight polyethylene (UHMWPE) is the preferred bearing material for total knee arthroplasty, yet its limited service life (15–20 years) remains a clinical challenge. This study investigates graphene oxide (GO) nanoplatelets as reinforcing fillers to enhance the mechanical and tribological performance of [...] Read more.

Ultra-high molecular weight polyethylene (UHMWPE) is the preferred bearing material for total knee arthroplasty, yet its limited service life (15–20 years) remains a clinical challenge. This study investigates graphene oxide (GO) nanoplatelets as reinforcing fillers to enhance the mechanical and tribological performance of UHMWPE for longer-lasting implants. GO/UHMWPE composites with 0–1 wt% GO were fabricated via solution blending and hot compression molding. Direct SEM imaging combined with oxygen elemental mapping confirmed uniform GO dispersion up to 0.5 wt%, whereas higher loadings induced agglomeration. Dynamic mechanical analysis showed that the storage modulus at 37 °C increased with GO content, peaking at 0.5 wt% (improved by ~28% over neat UHMWPE), then decreased due to aggregation. Tribological tests under dry reciprocating sliding revealed that GO progressively reduced the wear rate (up to ~45% at 1.0 wt%), but also raised the steady-state friction coefficient from 0.13 to 0.19, attributed to molecular chain anchoring. The optimal balance of enhanced stiffness and wear resistance, with only a marginal friction increase, was achieved at 0.5 wt% GO. The reinforcement mechanism involves efficient stress transfer to rigid GO sheets and reduced surface peeling. This work provides a robust processing route and direct dispersion evidence, offering practical guidance for designing high-performance UHMWPE composites for orthopedic applications. Full article

(This article belongs to the Section Tribology)

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18 pages, 2321 KB

Open AccessArticle

Yb-Doped ZrO₂ for Thermal Barrier Coatings: A Common Compositional Boundary at 1300 ℃

by He Tian, Limin He and Rende Mu

Coatings 2026, 16(8), 969; https://doi.org/10.3390/coatings16080969 - 14 Aug 2026

Abstract

Yttria-stabilized zirconia (YSZ) thermal barrier coatings suffer from t′ phase destabilization and insufficient thermal insulation above 1200 ℃. In this work, YbO_1.5-stabilized ZrO₂ powders (xYbSZ, x = 4–12 mol% YbO_1.5 on a cation basis, equivalent to 2–6 mol% Yb [...] Read more.

Yttria-stabilized zirconia (YSZ) thermal barrier coatings suffer from t′ phase destabilization and insufficient thermal insulation above 1200 ℃. In this work, YbO_1.5-stabilized ZrO₂ powders (xYbSZ, x = 4–12 mol% YbO_1.5 on a cation basis, equivalent to 2–6 mol% Yb₂O₃) were synthesized by chemical co-precipitation, consolidated by spark plasma sintering, and evaluated at 1300 ℃ in terms of phase stability, sintering behavior, thermal conductivity, and fracture toughness. A common compositional boundary near 8 mol% YbO_1.5 was identified across all four responses. 8YbSZ retained the metastable t′ phase with a monoclinic content below 10 mol% after 300 h at 1300 ℃, whereas grain coarsening accelerated markedly and the thermal conductivity reduction efficiency per unit doping at 1000 ℃ was approximately halved beyond this composition, with κ decreasing from 2.41 to 1.96 W·m⁻¹·K⁻¹ across the series. The toughness gain produced by thermal treatment fell from 34% (4YbSZ) to about 10% (10–12YbSZ) as the dominant toughening mechanism shifted from transformation and microcrack toughening (4–6 mol%) to ferroelastic domain switching (8 mol%), with both being lost in the compositions in which the cubic phase predominated. These results identify 8 mol% YbO_1.5 as the optimal composition balancing phase stability, sintering resistance, thermal insulation, and mechanical integrity for TBC applications at 1300 ℃. Full article

(This article belongs to the Special Issue Performance and Applications of Environmental Barrier Coatings (EBCs)/Thermal Barrier Coatings (TBCs))

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43 pages, 6364 KB

Open AccessReview

A Comprehensive Review of Polyurethane Composites: From Macro to Nano and Beyond

by Jasna V. Džunuzović, Ivan S. Stefanović and Enis S. Džunuzović

Coatings 2026, 16(8), 968; https://doi.org/10.3390/coatings16080968 - 14 Aug 2026

Abstract

Polyurethanes have attracted significant and constant attention since their initial introduction by Otto Bayer in 1937, primarily due to their inherent versatility. To expand their application potential and overcome limitations under extreme industrial conditions, the performance of pure polyurethanes is frequently enhanced through [...] Read more.

Polyurethanes have attracted significant and constant attention since their initial introduction by Otto Bayer in 1937, primarily due to their inherent versatility. To expand their application potential and overcome limitations under extreme industrial conditions, the performance of pure polyurethanes is frequently enhanced through the incorporation of adequate fillers. This review provides a comprehensive analysis of recent advancements in the field of polyurethane composites, focusing on the role of functional fillers in improving the properties of the polyurethane matrix. Special attention is given to the classification and effects of various types and sizes of the most commonly applied and promising fillers, including both individual and hybridized systems. Full article

(This article belongs to the Special Issue Functional Thin Films and Organic Polymer Coatings: Design, Characterization, and Applications)

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19 pages, 4861 KB

Open AccessArticle

Baicalin-Ternary LDH-Modified Magnesium Alloy with Anti-Corrosion and pH-Responsive Controlled Release, Near-Infrared-Enhanced Catalytic Property

by Yuhan Liang, Lijie Chen, Mingyue Feng, Tong Zhang, Rongbang Sun, Yang Liu, Yifu Fu, Yunxiang Chen and Lan Chen

Coatings 2026, 16(8), 967; https://doi.org/10.3390/coatings16080967 - 14 Aug 2026

Abstract

Aiming at the rapid corrosion of degradable magnesium alloys in physiological environments and the insufficient long-term protection of single plasma electrolytic oxidation (PEO) coatings, Mg-Mn-Fe layered double hydroxide (LDH) and baicalin (BA)-loaded LDH/BA composite coatings were prepared in situ on PEO-pretreated ZE21C magnesium [...] Read more.

Aiming at the rapid corrosion of degradable magnesium alloys in physiological environments and the insufficient long-term protection of single plasma electrolytic oxidation (PEO) coatings, Mg-Mn-Fe layered double hydroxide (LDH) and baicalin (BA)-loaded LDH/BA composite coatings were prepared in situ on PEO-pretreated ZE21C magnesium alloy substrates. BA was stably anchored on the LDH surface via coordination bonds between its oxygen-containing functional groups and laminate metal sites. Benefiting from the physical barrier of the LDH lamellar structure and the corrosion inhibition effect of baicalin, the LDH/BA coating significantly improved the corrosion resistance of the magnesium alloy matrix. The composite coating exhibited peroxidase-like catalytic activity for reactive oxygen species generation, which could be enhanced by near-infrared irradiation. It also possessed stable photothermal conversion performance and pH-responsive drug release behavior under acidic conditions. Biological characterization demonstrated that BA-loaded LDH composite coatings exert potent inhibitory effects on 143B cell proliferation. This work integrates long-term corrosion resistance, controlled drug release, and photoresponsive catalytic functions onto magnesium alloy surfaces, providing an effective strategy for developing high-performance biodegradable magnesium alloys. Full article

(This article belongs to the Special Issue Advanced Alloy Degradation and Implants, 2nd Edition)

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28 pages, 1077 KB

Open AccessReview

Research Progress of External Cavity Diode Lasers for Portable Quantum Precision Measurement

by Chenyao Huang, Jie Chen, Yikun Yang, Yuying Feng, Yixian Xie, Xi Cao, Zhengjie Guo, Fuyueyang Tan, Yuxuan Duan, Zaijin Li, Yi Qu and Lin Li

Coatings 2026, 16(8), 966; https://doi.org/10.3390/coatings16080966 - 14 Aug 2026

Abstract

Tunable external cavity diode lasers (ECDLs) are core light sources for portable quantum precision measurement, offering narrow linewidth, wide tuning range, and high spectral purity. This review systematically summarizes the research progress of ECDLs for portable quantum applications, classifying mainstream configurations into Littrow, [...] Read more.

Tunable external cavity diode lasers (ECDLs) are core light sources for portable quantum precision measurement, offering narrow linewidth, wide tuning range, and high spectral purity. This review systematically summarizes the research progress of ECDLs for portable quantum applications, classifying mainstream configurations into Littrow, Littman, fiber grating, and filter types. The structural principles, performance characteristics, and recent breakthroughs of each type are elaborated, with in-depth analysis of the trade-offs among tuning range, linewidth, side-mode suppression ratio (SMSR), and output power. Key progress in miniaturization and integration is highlighted, focusing on MEMS-driven tuning and silicon waveguide hybrid integration technologies, which address the conflict between performance and portability. Current challenges including mode hopping, thermal stability, and packaging loss are discussed, and future directions such as multi-band extension, isolator-free frequency stabilization, and AI-assisted control are prospected. This work provides a systematic reference for the development of compact, high-performance ECDLs toward field-deployable quantum sensors. Full article

(This article belongs to the Special Issue Research in Laser Welding and Surface Treatment Technology)

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14 pages, 2645 KB

Open AccessArticle

Silane-Assisted Interfacial Regulation of Recycled Wind Turbine Blade Powder-Reinforced Epoxy Composites

by Hongwu Zhang, Huafeng Wei and Heng Yue

Coatings 2026, 16(8), 965; https://doi.org/10.3390/coatings16080965 - 14 Aug 2026

Abstract

The stable crosslinked structure of glass-fiber-reinforced epoxy composites in end-of-life wind turbine blades complicates their recycling and reuse. Mechanically ground blade powder can be incorporated into new epoxy systems, but its heterogeneous surface composition and limited compatibility with the matrix restrict its reinforcing [...] Read more.

The stable crosslinked structure of glass-fiber-reinforced epoxy composites in end-of-life wind turbine blades complicates their recycling and reuse. Mechanically ground blade powder can be incorporated into new epoxy systems, but its heterogeneous surface composition and limited compatibility with the matrix restrict its reinforcing efficiency. In this study, sequential NaOH activation and KH560 treatment were used to regulate the surface characteristics of recycled wind-turbine-blade powder. FTIR and direct powder XPS measurements revealed changes in the hydroxylated silicate environment and the introduction of KH560-associated organic and organosilicon surface species. Representative SEM observations showed greater resin attachment and a more integrated local powder-matrix morphology after sequential treatment. At a fixed recycled-powder loading of 40 phr, corresponding to approximately 28.4 wt% of the total uncured mixture, EP-KH560 achieved mean flexural and tensile strengths of 67.00 and 38.81 MPa, respectively. These values were 47.8% and 57.1% higher than those of the composite containing untreated powder. Under the fixed formulation and processing conditions investigated, the results demonstrate that sequential NaOH/KH560 treatment improves the interfacial compatibility and comparative mechanical performance of recycled wind-turbine-blade powder/epoxy composites. Full article

(This article belongs to the Special Issue Polymer Composites for Functional Coatings: Synthesis, Characterization, and Applications)

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37 pages, 3186 KB

Open AccessReview

Recent Gel Coatings for Electrochemical Protection of Metallic Substrates

by Hany M. Abd El-Lateef and Ibrahim M. A. Mohamed

Coatings 2026, 16(8), 964; https://doi.org/10.3390/coatings16080964 - 13 Aug 2026

Abstract

Recently, gel coatings have been studied as a promising method that can provide electrochemical corrosion protection. This review presents a comprehensive analysis of advanced gels such as sol–gel coatings, hybrid organic–inorganic, self-healing, and crack repair gels. These gels employ different mechanisms for corrosion [...] Read more.

Recently, gel coatings have been studied as a promising method that can provide electrochemical corrosion protection. This review presents a comprehensive analysis of advanced gels such as sol–gel coatings, hybrid organic–inorganic, self-healing, and crack repair gels. These gels employ different mechanisms for corrosion protection, from passive barrier formation to active self-healing and corrosion inhibition. Their performance can be influenced by gel chemistry, microstructure, and the incorporation of functional additives. Recent studies have shown that gel coatings can achieve promising corrosion resistance. This high efficiency can be attributed to the formation of dense barrier layers that restrict the mobility of attacking ions. The incorporation of functional additives such as silica nanoparticles can enhance mechanical characteristics for gels. In the field of crack-repair, bio-gels based on microbially induced calcium carbonate precipitation show acceptable sealing capability. Additionally, the evolution of polarization resistance and corrosion current suggests the sustained protective performance of these gels. Multifunctional gels extend this concept by combining crack sealing, alkalinity restoration, and steel re-passivation. Gel coatings are transitioning from simple barrier coatings to multifunctional smart inhibition capable of self-healing, corrosion sensing, and long-term durability. This review highlights the relationship between gel chemistry, microstructure, and corrosion resistance for the development of next-generation gel coatings. Full article

(This article belongs to the Special Issue Smart Surface Engineering and Coatings for Corrosion Mitigation)

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45 pages, 14946 KB

Open AccessReview

Recent Advances in Photocatalytic Antibacterial Coatings: Fundamentals, Heterojunction Engineering, and Coating Strategies

by Pu Zhang and Wei Xiong

Coatings 2026, 16(8), 963; https://doi.org/10.3390/coatings16080963 - 13 Aug 2026

Abstract

Photocatalytic antibacterial coatings have emerged as a promising antibiotic-free strategy for combating healthcare-associated infections, biofilm formation, marine biofouling, and environmental microbial contamination. Unlike conventional antimicrobial approaches, photocatalytic systems continuously generate reactive oxygen species (ROS) under light irradiation, enabling broad-spectrum antimicrobial activity while minimizing [...] Read more.

Photocatalytic antibacterial coatings have emerged as a promising antibiotic-free strategy for combating healthcare-associated infections, biofilm formation, marine biofouling, and environmental microbial contamination. Unlike conventional antimicrobial approaches, photocatalytic systems continuously generate reactive oxygen species (ROS) under light irradiation, enabling broad-spectrum antimicrobial activity while minimizing the risk of antimicrobial resistance. This review systematically summarizes the fundamental mechanisms underlying photocatalytic antibacterial activity, including photogenerated charge-carrier dynamics, ROS generation pathways, and microbial inactivation processes. We further highlight recent advances in photocatalyst design, spanning conventional semiconductor photocatalysts, heterojunction engineering, cocatalyst modification, and two-dimensional material-assisted strategies for enhanced photocatalytic performance. Crucially, particular emphasis is placed on coating architectures and interfacial regulation, including encompassing fabrication methodologies, coating–substrate adhesion, internal heterointerface design, and coating–microorganism interactions, which dictate long-term durability and antibacterial efficacy. Finally, we explore the diverse applications of these coatings in medical devices, environmental remediation, and marine antifouling, while identifying current bottlenecks and future research trajectories toward developing durable, highly efficient, and clinically translatable antimicrobial surface technologies. Full article

(This article belongs to the Special Issue Eco-Friendly Antifouling Coatings and Paint in Marine Coating Systems)

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5 pages, 1196 KB

Open AccessReply

Reply to Pantokratoras, A. Comment on “Saleem et al. Thermal Case Study of Cilia Actuated Transport of Radiated Blood-Based Ternary Nanofluid Under the Action of Tilted Magnetic Field. Coatings 2022, 12, 873”

by Najma Saleem, Tahreem Ashraf, Ibtisam Daqqa, Sufian Munawar, Nazeran Idrees, Farkhanda Afzal and Deeba Afzal

Coatings 2026, 16(8), 962; https://doi.org/10.3390/coatings16080962 - 13 Aug 2026

Abstract

This reply presents a point-by-point response to the comments received from Pantokratoras in our previously published research article. The comments highlighted that the values of electrical conductivity assigned to alumina (Al₂O₃), silicon dioxide (SiO₂), and titanium dioxide [...] Read more.

This reply presents a point-by-point response to the comments received from Pantokratoras in our previously published research article. The comments highlighted that the values of electrical conductivity assigned to alumina (Al₂O₃), silicon dioxide (SiO₂), and titanium dioxide (TiO₂) nanoparticles were not appropriate and the experimental value of the Prandtl number for blood should remain within the range of 29–32. In response the electrical conductivity values for each nanoparticle were corrected and revised the Prandtl number values accordingly. The recomputed findings revealed that only small changes appeared in quantitative results while the overall trends and insights remained same. Full article

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4 pages, 194 KB

Open AccessComment

Comment on Saleem et al. Thermal Case Study of Cilia Actuated Transport of Radiated Blood-Based Ternary Nanofluid Under the Action of Tilted Magnetic Field. Coatings 2022, 12, 873

by Asterios Pantokratoras

Coatings 2026, 16(8), 961; https://doi.org/10.3390/coatings16080961 - 13 Aug 2026

Abstract

The base fluid in [...] Full article

9 pages, 2525 KB

Open AccessArticle

High-Temperature Oxidation Behavior and Oxide Layer Morphology of Silicon Carbide Surface

by Xiaotong Yin, Xiaojuan Yin, Ruixi Liu and Tiance Zhang

Coatings 2026, 16(8), 960; https://doi.org/10.3390/coatings16080960 - 13 Aug 2026

Abstract

The oxide interface on silicon carbide is a critical microstructural feature that enhances the mechanical properties of its reinforced composites; therefore, investigating the oxidation behavior and oxide layer morphology of silicon carbide is of great significance. This work systematically elucidates the oxidation behavior [...] Read more.

The oxide interface on silicon carbide is a critical microstructural feature that enhances the mechanical properties of its reinforced composites; therefore, investigating the oxidation behavior and oxide layer morphology of silicon carbide is of great significance. This work systematically elucidates the oxidation behavior and oxide layer morphology evolution of silicon carbide particles within the temperature range of 1100 to 1400 °C through quantitative analysis and visual characterization. Meanwhile, based on the measurement results of mass, particle size, and atomic ratio, three semi-quantitative estimation formulas for oxide layer thickness are derived (1.214rk, 2.226Δh, and 193pH/(213-126p), respectively), providing a reference for rapid assessment of oxide layer thickness when direct and macroscopic observation means are lacking. This work provides a reference for understanding the oxidation behavior of silicon carbide particles and for related composite material research. Full article

(This article belongs to the Special Issue Surface Modification, Matrix Modification and Interface Science in Composites)

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13 pages, 802 KB

Open AccessArticle

Fiberglass Layer Coating and Its Influence on the Properties of Concrete with F’c 210 Kg/cm²

by Bryan Jesús Albino Arbieto, Christian Serafin Ferrer Chavesta and Sleyther Arturo De La Cruz Vega

Coatings 2026, 16(8), 959; https://doi.org/10.3390/coatings16080959 - 13 Aug 2026

Abstract

Traditional structural strengthening methods involve high costs, increased self-weight of the structure, and complex construction procedures. In this context, there is a need for alternative materials that improve the mechanical performance of concrete without compromising its functionality. The objective of this study was [...] Read more.

Traditional structural strengthening methods involve high costs, increased self-weight of the structure, and complex construction procedures. In this context, there is a need for alternative materials that improve the mechanical performance of concrete without compromising its functionality. The objective of this study was to evaluate the effect of applying fiberglass layers to concrete with a design compressive strength of f’c = 20.59 MPa (210 kg/cm²). An applied research approach was used, with a quantitative methodology and a quasi-experimental design. Cylindrical concrete specimens measuring 12 cm × 6 cm were cured for 28 days and then coated with 1, 2, and 3 layers of fiberglass. The results showed that fiberglass has a chemical composition dominated by sodium (54.28%), silicon (25.64%), magnesium (9.98%), and aluminum (7.19%), which contributes to its stiffness and stability. Regarding compressive strength, the control specimens achieved an average strength of 20.69 MPa, while specimens coated with 1, 2, and 3 layers of fiberglass reached average strengths of 21.72 MPa, 23.49 MPa, and 25.71 MPa, respectively. These values represent increases of 4.98%, 13.53%, and 24.26% compared to conventional concrete. In terms of flexural strength, the control beams reached an average value of 3.50 MPa, whereas beams reinforced with 1, 2, and 3 fiberglass layers achieved average strengths of 3.66 MPa, 3.89 MPa, and 4.10 MPa, respectively. The results demonstrate that fiberglass improves both the compressive and flexural performance of concrete by providing external confinement, delaying crack propagation, and increasing the load-bearing capacity of the structural elements. It is concluded that fiberglass constitutes an effective and technically viable alternative for strengthening concrete structures. Full article

(This article belongs to the Special Issue Surface and Interfacial Engineering Strategies for Fiber-Reinforced Cementitious Composites)

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23 pages, 9340 KB

Open AccessArticle

Suspended-Target Laser Deposition of Bioactive Glass on Laser-Textured Magnesium Alloy

by Chenkai Zhu, Yong Wang, Zhenzong Shao and Libin Lu

Coatings 2026, 16(8), 958; https://doi.org/10.3390/coatings16080958 - 12 Aug 2026

Abstract

Rapid corrosion and poor coating adhesion continue to limit the use of magnesium alloys as temporary orthopedic implants. The two-stage laser process was developed to separate the high-temperature melting of 45S5 bioactive glass (BG) from the low-melting-point AZ31 substrate. Femtosecond-laser grids with spacings [...] Read more.

Rapid corrosion and poor coating adhesion continue to limit the use of magnesium alloys as temporary orthopedic implants. The two-stage laser process was developed to separate the high-temperature melting of 45S5 bioactive glass (BG) from the low-melting-point AZ31 substrate. Femtosecond-laser grids with spacings of 100, 200, and 300 μm were first produced on AZ31 to provide anchoring sites. Then, the target 45S5 BG was suspended above the substrate, locally melted with CO₂ laser, and transported onto the textured surface by gas jet. The 200 μm grid texture for Mg substrate with lowest water contact angle could give the highest tape-test adhesion rating (4B). At the selected deposition conditions of 20 W and 20 L·min⁻¹, two coating cycles produced a continuous layer approximately 50.5 μm thick. Relative to bare Mg alloy, this double-layer coating increased polarization resistance from 1.20 × 103 to 1.39 × 10⁵ Ω·cm² and decreased corrosion current density from 8.70 × 10⁻⁴ to 5.33 × 10⁻⁶ A·cm⁻². It also limited alkalization and mass loss during 28 days in simulated body fluid. As such, the double-layer surface coating supported apatite formation and improved MC3T3-E1 proliferation and alkaline phosphatase activity. These findings indicated that suspended-target deposition was able to form adherent, bioactive glass coatings on magnesium while limiting direct thermal damage to the substrate. Full article

(This article belongs to the Special Issue Smart Alloy Corrosion and Wear Resistant Coatings: Functionalities and Applications)

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26 pages, 2012 KB

Open AccessReview

Surface Modification Technology for Wooden Table Tennis Sole Plates: Coordinated Optimization of Coating Protection and Acoustic Performance

by Huixiang Wang, Guoyuan Huang and Byungchan Lee

Coatings 2026, 16(8), 957; https://doi.org/10.3390/coatings16080957 - 12 Aug 2026

Abstract

This review paper systematically investigates the surface modification technology of wooden table tennis blades, with a particular focus on the inherent conflict between coating-induced protection and the preservation of acoustic performance—a critical yet underexplored aspect of blade design. While protective coatings are essential [...] Read more.

This review paper systematically investigates the surface modification technology of wooden table tennis blades, with a particular focus on the inherent conflict between coating-induced protection and the preservation of acoustic performance—a critical yet underexplored aspect of blade design. While protective coatings are essential for enhancing durability against moisture, wear, and impact, they inevitably alter the blade’s vibrational characteristics and acoustic feedback, compromising the tactile–auditory perception that elite players rely upon. The current literature predominantly treats protection and acoustics as separate design objectives, lacking an integrated framework to resolve their inherent trade-off. To address this gap, this review establishes a material–structure–function integrated design paradigm that elucidates the synergistic optimization of coating protection and acoustic response. We systematically analyze the regulatory mechanisms of key coating parameters—specifically elastic modulus, density, and damping coefficient—on blade vibration modes and impact sound characteristics, demonstrating that conventional singular optimization inevitably leads to undesirable frequency shifts and diminished tactile feedback. Our synthesis of materials science, acoustic analysis, and biomechanics reveals that the key to synergy lies in constructing a mechanical impedance-matching transition system through material selection and thickness gradient design. Notably, we show that a multi-layer gradient coating architecture, guided by finite element simulation, can enhance protective performance by 40% while restricting acoustic deviation to within 5%, validating a rational “design–simulation–verification” closed-loop methodology. Furthermore, this review identifies critical research frontiers, including smart adaptive coatings and sustainable bio-based materials, and proposes a multi-objective optimization framework to bridge the gap between laboratory innovation and manufacturable, high-performance sporting equipment. This work provides a foundational theoretical roadmap for the next-generation design of competition-grade table tennis blades, balancing durability with the nuanced sensory demands of elite athletes. Full article

(This article belongs to the Special Issue Modern Methods of Shaping the Structure and Properties of Coatings, 2nd Edition)

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