In this study, a variety of magnetron sputtered binary and ternary thin film (approximately 1.5 μm thick) coatings using Cr, Al, and C as base elements were deposited onto Ni-201 alloy and investigated before and after exposure to simulated Type Ⅱ Hot Corrosion environment. Prototypical Na_2SO_4 was applied to the samples before exposure for 250 hours in an air/SO_2 gas mixture at 700 °C. It was determined that all coatings reduced the samples specific mass gains (corrosion rates) when compared to uncoated ones. Binary Al - C and Cr - C coatings were completely dissolved after exposure testing and NiO was the only compound detected on the surfaces; whereas continuous layers of Al_2O_3 and Cr_2O_3 were detected in Cr - Al and Cr - Al - C coated samples, indicating good protection against Type Ⅱ Hot Corrosion.
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