In order to address the issue of metal corrosion in marine environments，applying organic coatings to the surfaces of marine equipment is a proven and effective strategy.However，organic coatings are inevitably eroded by corrosive media during service，leading to gradual degradation of their performance.MXene nanosheets have been widely used to enhance the corrosion resistance of organic coatings due to their large specific surface area，high impermeability and excellent interfacial compatibility.Currently，research on the corrosion protection of MXene-modified organic coatings primarily focuses on surface and interfacial design and their anti-corrosion mechanisms.Based on an overview of research progress in MXene-modified organic coatings，this paper discussed the key factors influencing the corrosion resistance of the composite coatings and their protection mechanisms.Finally，future development directions for MXene-modified organic composite coatings were proposed.

Quantum dots have attracted much attention due to their excellent biocompatibility，high specific surface area，ease of surface functionalization and diverse preparation methods.In recent years，significant progress has been made in the application of quantum dots in the field of corrosion protection.This paper first outlined various types of quantum dots，and conducted a comparative analysis of common synthesis technologies along with their respective advantages and disadvantages.Subsequently，the performance of quantum dots as corrosion inhibitors in various corrosive environments was summarized，along with the current research status of their application as nano-fillers to enhance the anti-corrosion properties of polymer coatings.Finally，this paper elucidated the corrosion protection mechanisms of quantum dots and their functionalized modified coatings.The current challenges and future development trends of quantum dots in the field of corrosion protection were discussed.

With the deepening of the strategy of marine resources development，the wide application of pure titanium with excellent corrosion resistance in marine engineering equipment is facing the severe challenge of microbiologically influenced corrosion (MIC).In this study，the microbial corrosion behavior of pure titanium was investigated through bacterial culture，electrochemical testing，surface morphology characterization and corrosion product analysis with the dominant marine bacterial species Pseudomonas aeruginosa (P.aeruginosa) as the research object.This study systematically revealed the corrosion failure mechanism of TA2 pure titanium under the action of biofilm.Results showed that P.aeruginosa accelerated the corrosion process of TA2 pure titanium.At the initial stage of immersion in a bacterial-containing environment，the biofilm temporarily protected the substrate through the physical barrier effect.With the prolongation of immersion time，the biofilm detached，and the depth of surface pitting increased compared with that in the sterile environment，with the decrease of charge transfer resistance and the increase of corrosion current density.On the one hand，the TiO2 content in the surface passivation film decreased in the bacterial environment，and the formation of metastable Ti2O3/TiO reduced the compactness of the film layer，formed local defects and induced pitting initiation.On the other hand， P.aeruginosa might mediate electron transfer between bacteria and metals by secreting electron carriers such as pyocyanin (PYO).Generally，the research results provide theoretical support for the corrosion prediction of marine equipment and the development of microbial protection technologies，which is of great significance to enhance the service safety and economic efficiency of marine engineering materials.

To address the common issue of tribocorrosion coupling failure of metallic moving components in marine environments，this study designed and developed a wear/corrosion-resistant multi-principal element alloy (MPEA).The AlCoCr1.8Fe0.2Ni2.1 MPEA composition was optimized via CALPHAD phase diagram calculations，and the as-cast alloy was fabricated through vacuum melting.Results showed that the alloy had a FCC＋B2＋BCC three-phase structure，forming a microstructure consisting of FCC network skeleton and nanoscale BCC/B2 coherent structures.In comparison with the classical AlCoCrFeNi2.1 MPEA，the AlCoCr1.8 Fe0.2 Ni2.1 alloy exhibited a 100 MPa enhancement in yield strength，a 120 HV increase in hardness，a 30%reduction in tribocorrosion rate in 3.5%(mass fraction) NaCl solution，and an 84%decrease in corrosion current density，accompanied by significantly improved passive film stability.These improvements were attributed to the higher Cr content promoting coherent precipitation of Cr-rich nanophases within the B2 matrix.The abundant coherent phase boundaries effectively impeded dislocation motion，thereby enhancing the alloy strength.Meanwhile，the abundant coherent phase boundaries also accelerated the surface repassivation rate，thereby further enhancing the alloy tribocorrosion resistance.This study provides novel insights into the design of metallic structural materials for marine engineering applications.

The S460 steel produced via the new-generation thermomechanical controlled process (TMCP) exhibits superior fatigue resistance and better corrosion resistance，and is expected to be widely used in the field of wind power equipment.In this work，a six-month real-sea exposure test was conducted on S460 steel across four marine zone environments (atmospheric zone，splash zone，tidal zone，and full immersion zone) in the Sanya sea area.The corrosion behavior of S460 steel in different zone environments was studied by measuring corrosion rate，observing morphology and analyzing the composition of corrosion products.Results showed that after six months of real-sea exposure testing，the specimens in the splash zone exhibited the highest corrosion rate.The distinct environmental conditions across different marine zones significantly influenced the formation of corrosion products on the specimens.In particular，the sufficient oxygen in the splash zone was conducive to the formation of Fe3O4 on the specimens.In contrast，due to the periodic immersion of seawater，the electrolyte layer on the specimens in the tidal zone persisted，which promoted the formation of γ-FeOOH.All specimens exhibited localized corrosion on their surfaces.Specifically，the localized corrosion pits on the specimens in the atmospheric zone were small in diameter and depth and densely distributed，while the specimens in the splash zone showed obvious localized corrosion pits with greater depth.

In order to study the corrosion resistance of graphene oxide/melamine phosphate waterborne composite coatings in marine environments，melamine phosphate was used to covalently functionalize graphene oxide，and the modified graphene oxide was added to waterborne polyurethane to prepare waterborne composite coatings of functionalized graphene oxide.The structure and microstructure were comparatively analyzed via Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM).Corrosion resistance salt spray tests，polarization curve measurements and adhesion strength tests were conducted.Results showed that when the mass ratio of graphene oxide to melamine phosphate in the composite was 1 ∶3 and the addition amount of modified graphene oxide was 0.8 g，the corrosion protection efficiency of the composite coating reached 99.78%.Meanwhile，the coating exhibited an adhesion strength of 4.09 MPa，with a 49%adhesion loss rate after 168 h of salt spray test.The coating's hardness was 5H.Contact angle measurements revealed that the addition of modified graphene oxide increased the coating’s contact angle from 77.3°±1.0° to 99.8°±0.6°.Overall，the graphene oxide/melamine phosphate waterborne coating exhibited excellent corrosion resistance，which was better than both pure melamine phosphate coatings and graphene oxide coatings.