This paper reports the use of HVOF-sprayed corrosion resistant alloy (CRA) coatings to protect carbon steel in supercritical CO2-containing environments. 316L, Ti, alloy C- 276 and alloy 625 were sprayed onto carbon steel substrate using a JP-5000 HVOF system and tested in 3.5wt.% NaCl solution at 10 MPa in a mixture of 95% CO2 and 5% H2S at 40°C for 30 days. Microstructural characterization revealed that the coating protected the steel substrate from supercritical CO2/H2S corrosion. The bare steel formed a sulphide scale while no such scale was seen in the case of CRA-coated steel. It can be concluded that thermally sprayed CRA coatings provide a cost-effective corrosion mitigation method for infrastructure likely to be in contact with wet supercritical CO2/H2S. However, care must be taken to ensure that the thermally sprayed layer does not have any through-thickness porosity; else, such coatings may accelerate corrosion of the underlying steel due to galvanic interactions.

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