Reclamation Information Sharing Environment (RISE)

Coating systems currently specified for use to protect Reclamation’s aging infrastructure are expected to only provide 20-30 years of service before needing replacement. Legacy coating systems like lead-based alkyds, a type of coating called inhibitor coatings, exhibit service lives upwards of 80 years. Unlike barrier coatings that passively act as an obstacle to block the electrolyte from reaching the metal substrate and causing corrosion, inhibitive coatings actively prevent corrosion by stunting or polarizing the reaction. This work comprehensively studied modern inhibitive coating systems through electrochemical impedance spectroscopy (EIS) and rust creep evaluation to understand the resulting barrier properties when subject to accelerated weathering. Adhesion strength, impact resistance, and cathodic disbondment were also evaluated with the overall goal of identifying an inhibitive system that may withstand Reclamation’s severe service environments and outperform commonly used barrier coatings. One system containing metallic zinc inhibitors did perform as well as the benchmark, but long-term testing is still needed to better evaluate performance.