The Role of Zinc Particle Size and Loading in Cathodic Protection Efficiency

Abstract

THE ROLE OF ZINC PARTICLE SIZE AND LOADING IN CATHODIC PROTECTION EFFICIENCY By Qiang Wang, Master of Science A Thesis submitted in partial fulfillment of the requirements for the degree of Master of Science at Virginia Commonwealth University. Virginia Commonwealth University, 2012 Major Director: Dr. BRIAN HINDERLITER, Ph. D Associate professor, Department of Mechanical and Nuclear Engineering Metallic additives, also known as anticorrosive pigments, can provide sacrificial cathodic protection and complement the barrier protection afforded by heterogeneous organic coatings to metallic substrates. The unique systematic study of the corrosion resistance of an epoxy coating reinforced with different sizes (80nm, 500nm, 10um) and continuous multiple pigment volume concentration (0, 2%, 10%, 20%, 45%) below global critical pigment volume concentration of zinc particles were studied. The thesis is developing the fundamental understanding to optimize corrosion protection and predicting the protection with time. The properties of these cathodic coatings were investigated by a single-frequency electrochemical impedance spectroscopy (EIS) and open circuit potential xiv (OCP) measurements that can be used as to understand cathodic protective state. Finite Element Analysis (FEA) has been applied here for modeling and simulating part of actual experiments. This thesis will help understanding the sensitivity and efficiency to various size and loading of metallic additives for corrosion protection.