Hot corrosion behaviour of different Cr_3C_2-NiCr coatings on boiler tube steel at elevated temperature

摘要

Purpose - This paper aims to investigate hot corrosion behaviour of different Cr_3C_2-NiCr coatings on boiler tube steel. Design/methodology/approach - High velocity oxy fuel technique has been used to deposit different coatings on commercially available ASTM-SA213-T22 boiler tube steel. The hot corrosion studies have been performed in molten salt environment at 900°C temperature in silicon tube furnace in laboratory. Findings - The results showed that uncoated superalloy suffered intense spalling and the weight change was massive during each cycle on studies of hot corrosion 900°C. The 100 per cent NiCr and 10 per cent (Cr_3C_2) - 90 per cent (NiCr) coatings provided better protection to T22 steel against the hot corrosion because of the formation of Ni and Cr_3C_2 layers. Originality/value - In this research a variety of coatings have been used. This research work has been aimed to investigate the hot corrosion behavior of Boiler Steel b with different Cr_3C_2-NiCr coatings, under molten salt environment in Silicon tube furnace at 900°C, under cyclic conditions.