Data de lançamento: 2026-01-08
Taxa de clique: 46
Marine biofouling and corrosion pose serious threats to the safety and longevity of ships and offshore structures. These issues can lead to increased fuel consumption, the introduction of invasive species that disrupt marine ecosystems, reduced operational efficiency, and even system failures. As a result, the development of high-performance antifouling and anticorrosion technologies is essential for ensuring the safety and sustainable development of marine engineering.
Innovative Antifouling Coating Technologies
Low-surface-energy coatings, which leverage the synergistic effects of polydimethylsiloxane (PDMS) and fluoropolymers, effectively reduce surface energy (contact angle >110°), thereby inhibiting microbial adhesion. The problem of inadequate mechanical strength has been addressed through multilayer structural designs. Biomimetic coatings, inspired by the micro/nanostructures of shark skin, achieve superhydrophobicity (static contact angle >150°) and have demonstrated more than an 85% reduction in biofouling under laboratory conditions. Conductive coatings generate disinfectants such as sodium hypochlorite through electrochemical reactions, reaching antibacterial efficiencies of up to 90% in copper–aluminum composite systems. However, their reliance on a continuous power supply remains a limitation for practical applications.
Breakthroughs in Anticorrosion Coating Systems
Polyurea coatings, known for their rapid curing properties (hard-dry time <30 seconds) and tunable molecular chain segments, have shown significant improvements in performance. When sulfonated graphene (SG) is incorporated into a waterborne polyurethane-acrylate (WPUA) system, a composite coating with just 0.3% SG achieves an impedance increase of three orders of magnitude. In metal-based alloy coatings, the addition of magnesium and rare earth elements to zinc–aluminum alloys promotes the formation of dense passivation films, reducing corrosion area by 70% after 168 hours of salt spray testing. High-entropy alloy (HEA) coatings, such as FeNiCoCrMoₓ, form sandwich-structured passive films in 3.5% NaCl solution, with self-corrosion current densities as low as 10⁻⁸ A/cm², demonstrating exceptional resistance to pitting corrosion.
Fig. SEM image of cross-section of high-entropy alloy coating
Expansion of Applications for Novel Materials
In ceramic coatings, Cr/CrAlN multilayer structures fabricated via ion plating exhibit a hardness above HV0.3 > 2000 and reduce corrosion current density to one-tenth that of the substrate, effectively overcoming the cracking issues commonly found in traditional single-layer coatings. Graphene modification technologies enhance the chloride ion resistance of epoxy coatings by 80%, with the impedance modulus maintained at 10⁶ Ω·cm² for over 200 days during simulated seawater immersion tests.
Performance–Cost Trade-off
High-entropy alloy (HEA) coatings have a raw material cost of up to $122/kg—approximately 800 times that of conventional organic coatings—making them impractical for large-area applications such as ship hulls. Photocatalytic coatings suffer a 90% drop in activity in shaded areas of hulls, necessitating auxiliary UV systems, which further increase system complexity.
Environmental Compatibility Issues
Metal-based coatings containing copper ions (LC₅₀ = 4.5–8.7 mg/L) and hexavalent chromium (WHO limit = 0.05 mg/L) pose ecological toxicity risks, prompting the need for safer elemental alternatives. In self-polishing coatings, even a ±0.1 µm/month deviation in hydrolysis rate can lead to fluctuations of up to 30% in the antifouling cycle.
Material Compatibility Limitations
Silicone-based coatings exhibit poor adhesion to metal substrates (bonding strength <5 MPa), requiring epoxy modification to enhance adhesion to ≥15 MPa. Ceramic coatings suffer from thermal expansion mismatch (Δα > 8 × 10⁻⁶ /°C), which induces interfacial microcracks; multilayer gradient structures can mitigate stress concentration by up to 40%.
Future Development Directions
Development of Smart-Responsive Materials
pH/Cl⁻ dual-responsive polyurethane systems are being developed to achieve self-healing efficiencies exceeding 120% at damaged sites through dynamic disulfide bond exchange. Photothermal conversion coatings based on carbon nanotube composites can generate localized temperature increases of up to 50 °C, effectively inhibiting barnacle larval adhesion.
Optimization of Biomimetic Structures
MXene/polyurethane-based biomimetic coatings combine the “maze effect” with controlled-release corrosion inhibitors, reducing corrosion rates to as low as 0.002 mm/a. Coral-like microporous structures (pore sizes 5–50 μm) are also being developed, which use fluid dynamics to reduce bioadhesion probability by 30%.
Green Fabrication Technologies
The substitution rate of bio-based polyols is targeted to reach 60%, while VOC emissions are expected to be reduced below 50 g/L. Precision in laser cladding technology has improved to ±20 μm, leading to a 40% reduction in the processing cost of high-entropy alloy coatings.
Pathways to Industrial Application
In the shipbuilding sector, a triple-layer protective system—comprising epoxy zinc-rich primer, polyurea intermediate layer, and fluorosilicone topcoat—has been established for hull coatings, extending dry-docking intervals from 2 to 5 years. For offshore platforms, the development of nickel-based alloy–ceramic composite coatings has enabled oil production tubing to withstand H₂S corrosion for over 10 years. In subsea equipment, alternating CrAlN/TiAlN multilayer coatings have reduced wear rates of propeller shaft systems to below 0.01 mm³/(N·m), meeting maintenance-free requirements across the entire service lifecycle.
Marine antifouling and anticorrosion coating technologies have evolved into a comprehensive technical matrix integrating organic–inorganic hybrid materials with synergistic static protection and dynamic responsiveness. Future efforts should focus on improving environmental adaptability and controlling total life-cycle costs. Accelerated development of advanced coatings through materials genome engineering is essential, along with the establishment of a complete technology chain that includes performance databases, failure models, and service-life evaluation systems. Further exploration is needed into large-scale application techniques and predictive models for in-service longevity of coating systems.
To validate the long-term corrosion resistance of advanced coating systems—such as high-entropy alloys, ceramic composites, and smart-responsive polymers—accelerated testing under controlled environments is essential. BEVS salt spray testers provide precise, repeatable testing conditions in compliance with international standards (e.g., ASTM B117, ISO 9227), enabling accurate evaluation of coating performance over simulated service lifespans. Whether for R&D or quality assurance, our testers are a critical tool in advancing durable marine protection technologies.
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