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This study provides new insights into the development of high-performance MXene-reinforced coatings to strengthen polymeric nanocomposites by enhancing microstructure, anti-aging properties, corrosion resistance, and robustness. MXene nanoparticles, labeled 25C and 80C, were synthesized using two different methods and incorporated at concentrations ranging from 0.1 to 2.0 wt.% into epoxy composites. The results demonstrated that 80C MXene, characterized by its finer morphology and superior dispersion, significantly improved the composite's performance compared to 25C. Electrochemical Impedance Spectroscopy (EIS) tests, along with long-term exposure assessments, suggested that incorporating both types of MXene nanoparticles enhances the corrosion protection performance of epoxy coatings over time. Micro-CT analysis revealed that both types of MXene substantially reduced defects and voids in the polymeric matrix, resulting in enhanced protective performance. This void reduction confirms that the incorporation of both 25C and 80C MXene improves microstructural integrity by filling voids and creating a more continuous, uniform structure, particularly in samples with 0.1% to 1.0% MXene flakes. The findings also highlighted MXene's potential in modifying the anti-aging properties of epoxy by inhibiting free radical generation and enhancing the composite's resistance against corrosion. Both 25C and 80C MXene-epoxy groups exhibited a clear trend of diminishing free radical intensity with increasing MXene concentration up to 1.0%, with free radical intensity reduced by over 40% compared to neat epoxy. The relationship between MXene concentration and reinforcement was also investigated, revealing superior corrosion protection properties at concentrations of 0.5-1.0 wt.%. This research offers a profound understanding of MXene's potential in polymer-based composites, laying a foundation for future investigations aimed at utilizing MXene to achieve superior material properties for a wide range of applications, particularly in the realm of metallic surface protection. 

This study examined the influence of laboratory corrosion testing methods, specifically salt spray, and immersion tests, on the long-term performance assessment of wire-arc-sprayed Zn-Al coatings. Two Zn-Al alloyed systems, Zn-15Al and Zn-Al pseudo-alloy, were selected for investigation, subjecting them to 1000 h of immersion and salt spray conditions. Electrochemical impedance spectroscopy was used to monitor corrosion progression in both coating systems at 200-h intervals. Post-exposure, the coatings underwent microstructural and chemical characterization, along with potentiodynamic polarization tests. Furthermore, some specimens in both coating systems were intentionally damaged and exposed to 1000 h of salt spray and immersion testing and analyzed with scanning electron microscopy. Immersion testing yielded similar results for both coatings, while salt spray testing unveiled significant differences and highlighted the susceptibility of the Zn-15Al to salt spray in both undamaged and damaged states. The continuously refreshed salt spray electrolyte hindered stable corrosion product formation, allowing chloride penetration and increased corrosion in Zn-15Al. Conversely, the Zn-Al pseudo-alloy coating formed Al (OH)3, acting as a barrier against chloride penetration during salt spray and offering superior protection. In summary, salt spray testing proved more aggressive than immersion when evaluating Zn-Al coatings with high zinc content primarily relying on active dissolution for corrosion protection. 

This study explored the enhancement potential of MXene, a novel two-dimensional material, in epoxy-based nanocomposites; which comprehensively examined the influence of MXene on epoxy's viscosity, void formation, aging resistance, mechanical properties, and anti-wear properties. MXene nanofillers, labeled as 25C and 80C, fabricated via different acid-etching methods, were incorporated into epoxy resin at varying weight percentages (0.1-2.0 wt.%). Observations revealed that for both varieties of MXene, inclusion of 1.0 wt.% MXene led to the mitigation of void content, whereas the incorporation of 2.0 wt.% MXene yielded maximal enhancements in both tensile strength and abrasion resistance. Additionally, the integration of 1.0 and 2.0 wt.% MXene displayed superior aging resistance, with around 80% reduction in free radical formation compared to the unmodified epoxy, while maintaining its excellent mechanical properties after QUV exposure. Therefore, both MXene types significantly enhanced the performance of epoxy composites, with the 80C-MXene displaying marginally superior enhancement due to its smaller particle size and higher purity, as identified by SEM and TEM images. 

This paper examines the impact of fire on the microstructural, mechanical, and corrosion behavior of wire-arc-sprayed zinc, aluminum, and Zn-Al pseudo-alloy coatings. Steel plates coated with these materials were subjected to temperatures in increments of 100 °C, starting from 300 °C and progressing until failure. Microstructural characterization, microhardness, abrasion resistance, and electrochemical impedance studies were performed on the post-fire coatings. The findings from this study show that heat had a positive impact on the performance of zinc and Zn-Al pseudo-alloy coatings when they were exposed to temperatures of up to 400 °C, while aluminum coatings maintain their performance up to 600 °C. However, above these temperatures, the effectiveness of coatings was observed to decline, due to increased high-temperature oxidation, and porosity, in addition to decreased microhardness, abrasion resistance, and corrosion protection performance. Based on the findings from this study, appropriately sealed thermal-spray-coated steel components can be reused after exposure to fire up to a specific temperature depending on the coating material.