Analysis of cold spray‐coated boiler‐tube material in a chlorine‐based corrosive environment at 900°C

Abstract

Energy generation, especially through waste incinerators is the need of the hour, as it serves the dual purpose of waste management and enhances the energy bank. However, mainly because of the presence of chlorine elements in the waste, there is an extensive corrosive failure of incinerator components utilized for energy generation. Therefore, there is need to work on enhancing the material life in these or similar plants, which will further increase plant efficiency. In this study, a corrosion‐resistant coating of 75%Cr3C2–25%NiCr is tested in a Na2SO4–10%NaCl environment at 900°C under cyclic conditions. The 289‐μm‐thick cold spray‐coating was dense (porosity, 0.925%), hard (average, 866 HV) and smooth with a surface roughness of 6.07 μm. Tribology tests on the pin‐on‐disc machine gave an average mean friction coefficient of 0.071 ± 0.006. The coating microstructure developed shows corrosion protective ability under chlorine‐containing high‐temperature conditions, with an overall weight gain of 10.235 mg/cm2, which is 60.9% less in comparison to the 26.177 mg/cm2 shown by the bare alloy. The coating acts as a shield to the substrate against corrosion attack.

Study and comparison of wear behaviour of Ni-Al2O3 coatings deposited by hot and cold spray

“…Therefore, as the literature revealed [42,[47][48][49][50], the Ni-Al 2 O 3 coatings deposited by the cold-spray technique are effective in resisting high-temperature corrosion but these coatings are found not much efficient in resisting material loss due to wearing especially when compared with hot spray deposition techniques.…”