New types of ceramic coatings based on SiO₂-Na₂O-B₂O₃-TiO₂ oxide phases were investigated as protection for boiler steel in power generation systems. Low-alloyed Cr-Mo 16Mo3 steel was coated with different compositions of enamel coatings to assess the protective potential of these coatings under water vapor at high temperatures. Oxidation at 650 °C for 50 h in Ar + water vapor was performed in a TGA apparatus to investigate the oxidation kinetics. The results indicate that the ceramic coatings provided a high degree of protection for the steel exposed to such conditions compared to the uncoated 16Mo3 steel. Furthermore, despite the formation of cracks in the coatings, no spallation from the steel surface was observed. Interconnected porosity in the coatings is suspected to provoke interfacial degradation.

Magnesium alloys, due to their unique properties, low density and high strength properties, are becoming more frequently used in industrial applications. However, a limitation of their use may be the need to ensure high abrasive wear resistance and corrosion resistance. Therefore, magnesium alloys are often protected by applying protective coatings. The paper presents the influence of the modification of the electrolyte composition, with or without the addition of borax, on the morphology (observed by SEM method) and phase composition (analyzed by EDS and XRD) of the formed layers on the AZ91 magnesium alloy, and their abrasive wear (determined with Ball-on-Disc method) and corrosion resistance (evaluated using the immersion method and by electrochemical tests), especially in chloride solutions. It has been clearly demonstrated that the modification of the electrolyte composition significantly impacts the final properties of the protective coatings on the AZ91 alloy formed by the plasma electrolytic oxidation (PEO) process. On the basis of the results, it was found that the new type of PEO coatings with the borax addition, compared to base PEO coatings, showed significantly higher abrasion resistance and an order of magnitude lower corrosion rate.