Effect of Sealing Materials and Parameters on the Corrosion Resistance of HVOF-Sprayed CrC-NiCr Coatings

School of Materials Science and Engineering, Pusan National University, 63 Busandaehak-ro, Geumjeong-gu, Busan 609-735, Korea(Received October 17, 2014 ; revised December 1, 2014 ; accepted December 1, 2014)AbstractEffects of sealant and sealing procedure on corrosion resistance of high velocity oxy-fuel (HVOF) sprayedcoatings were studied. HVOF-sprayed CrC-20NiCr coatings were sealed using three commercial sealants basedon phenolics and epoxy. Penetration depth of sealants, measured by fluorescent microscope technique, wasbetween 19µm and 340µm depending on sealant, sealing condition or sealing procedure. It was found thatsealing on rotation status was more effective than that on stationary specimen due to the Coriolis effect offluid in pores of the coating. From the CASS results, corrosion resistance of properly sealed CrC-20NiCrcoatings was equal to that of hexa-valent chromium plating.