Extended Connectivity of Zinc Pigments to Provide Enhanced Galvanic Coupling by Partial Replacement with Nano-particles
Conference
Fancy, SF, Lau, K, Sabbir, MA et al. (2019). Extended Connectivity of Zinc Pigments to Provide Enhanced Galvanic Coupling by Partial Replacement with Nano-particles
. 2019-March
Fancy, SF, Lau, K, Sabbir, MA et al. (2019). Extended Connectivity of Zinc Pigments to Provide Enhanced Galvanic Coupling by Partial Replacement with Nano-particles
. 2019-March
Zinc rich primer coatings (ZRP) have become widely used since the 1980's for corrosion mitigation. The effectiveness of the ZRP coating strongly depends on the pigment volume concentration and bonding to the steel substrate. Beneficial cathodic polarization occurs when the dispersed zinc pigments have continuity with the steel substrate. Carbon nano-particles are being considered in the development of the ZRP coating systems considering its physical, electrical and mechanical properties. Therefore this is of interest to identify the extent of possible corrosion mitigation of a nano-particle enriched epoxy primer coating (NPE-ZRP). In order to assess the effect of nano-particles on zinc electrochemical coupling, the extent of zinc consumption, steel corrosion development, and coating degradation were addressed. The test condition of major importance to promote electrochemical activity of the zinc, includes both oxidation and reduction reactions. A traditional ZRP coating was studied to reference the performance of nano-particles. After exposure, physical parameter such as disbondment length, pull-off strength and cross-sectional micrographic analysis were done to elucidate the nano-particles influence. Apparent enhanced continuity of zinc pigments due to either improved conductivity or higher coating mechanical adhesion afforded by the nano-particles was observed.
