Vibrational Corrosion Potential of HastelloyC Coatings by GS-HVOF Spraying

Coatings of HastelloyC fabricated by HVOF spraying with a gas shroud (GS) have shown the superior barrier characteristic and corrosion resistance in seawater environment. During immersion of these coatings in artificial seawater, however, vibrational behaviour of the corrosion potential was observed. Some types of surface modification of the sprayed coatings and changing of the spray condition were carried out and their effect on the corrosion potential was investigated. It was revealed that the vibration is related to surface oxides formed during the spray process. Surface modification of the sprayed coatings and changing of the spray condition could reduce the vibration effectively.