Modes and Mechanisms of Degradation of Epoxy-Coated Reinforcing Steel in a Marine Environment.
Modes and Mechanisms of Degradation of Epoxy-Coated
Reinforcing Steel in a Marine Environment.
Nguyen, T.; Martin, J. W.
Durability of Building Materials and Components 7th.
Volume 1. Chapter 51. 1996, E&FN Spon, London,
England, Sjostrom, C., Editor(s), 491-502 pp, 1996.
coatings; concrete solution; corrosion; degradation;
marine; rebars; steels
Blasted-steel panels were coated with two commercial
powder epoxy coatings at two thicknessess. half of the
coated panels were scribed; the other half remained free
of defects. The panels were immersed in a saturated
calcium hydroxide aqueous solution containing 3.5%
sodium chloride maintained at either 35 or 50DGC.
Degradation was quantified by infrared thermography, wet
adhesion test, and microscopic and analytical
techniques. Unscribed panels exhibited only
water-induced adhesion loss, but scribed specimens
degraded by anodic blistering and cathodic disbondment,
in addition to water-induced adhesion loss. Anodic
blistering was attributed to localized crevice corrosion
under coating followed by blistering via an osmotic
pressure mechanism. Cathodic disbondment was caused by
the alkalinity of the corrosion products at the cathodic
sites. Water-induced adhesion loss was due to the
presence of multiple layers of water at the