Hot Corrosion Behaviour of Detonation-Gun Sprayed Cr3C2-NiCr Coating on Inconel-718 in Molten Salt Environment at 900 °C

Detonation gun sprayed Cr3C2-NiCr coating was deposited on nickel-based superalloy Inconel-718. Hot corrosion studies were conducted on uncoated as well as Cr3C2-NiCr coated superalloy in 75 wt% Na2SO4 + 25 wt% NaCl salt environment at 900 A degrees C for 50 cycles. The thermo-gravimetric technique was used to establish kinetics of corrosion. X-ray diffraction and scanning electron microscopy/energy-dispersive X-ray analysis techniques were used to analyze the corrosion products. The uncoated superalloy suffered intense spalling, while the Cr3C2-NiCr coating provided good protection against hot corrosion in the given salt environment.