High-Temperature Corrosion Behaviour of HVOF Sprayed Cr3C2- 25NiCr Coated on Alloy X22CrMoV12-1 at 600o C

Abstract

The present study investigates the hot corrosion behaviour of high-velocity oxy-fuel sprayed alloy X22CrMoV12-1 with Cr3C2-25NiCr coating at 600oC. The study was carried out by air and molten salt environment for both coated and uncoated substrates for 50 cycles. Thermogravimetry analysis was carried out to evaluate the hot corrosion by calculating the mass changes in each cycle. The results show that coating provides the marginally good corrosion resistance than the uncoated alloy. The formation of Fe2O3 and MoO3 phases in the uncoated substrates in both air and molten salt environments reduces the corrosion resistance at the high-temperature environment. The formation of Ni2Oand spinel oxide NiCr2O4 provided good resistance to corrosion in the coated substrates in the air and molten salt environment.