Hot corrosion resistance of plasma‐sprayed carbon nanotube reinforced ceramic coatings on T23 steel in boiler service

Abstract This research work investigates the high‐temperature corrosion behavior of ceramic coatings comprising alumina and carbon nanotube‐reinforced alumina (1, 3, and 4.5 wt.% CNT) deposited on T23 boiler steel using plasma spraying. The coated and uncoated samples were exposed for 1000 h at 900°C in a 250 MW operational thermal power plant boiler to simulate real service conditions. Corrosion performance was analyzed using thermogravimetric analysis, X‐ray diffraction, scanning electron microscopy, and energy‐dispersive spectroscopy. The CNT‐reinforced ceramic coatings significantly reduced the corrosion rate to 28.27 mpy (mils per year), compared to 110.64 mpy for alumina‐only and 328.54 mpy for uncoated steel, owing to improved microstructural integrity and reduced porosity. While the findings demonstrate the coatings' strong applicability for high‐temperature environments, the study is limited to a specific boiler condition and exposure duration, suggesting the need for broader validation under diverse operational parameters. These coatings have direct practical implications for improving boiler durability, reducing maintenance costs, and enhancing operational reliability. Furthermore, this work contributes to sustainable development goals by supporting energy efficiency, industrial innovation, and responsible consumption and production. The research offers original insights into the real‐world performance of CNT‐reinforced ceramic coatings for advanced corrosion protection in thermal power applications.