51312-01656-Flow-Accelerated Coating Degradation: Influence of the Composition of Working Fluids

Available for download

Product Number: 51312-01656-SG

ISBN: 01656 2012 CP

Author: Gordon P. Bierwagen

Publication Date: 2012

Member Price: $0.00

Non Member Price: $20.00

Price: $20.00

Qty:

Water percolation into the metal-coating interface is usually the main cause of the loss of barrier properties of coatings and leads to coating delamination and under-film corrosion. Recently flowing fluid accelerated coating degradation has been received more attention since flowing liquids may enhance the transport of ions oxygen and water through the coating film abrade the coating surface with fluid shear and degrade the barrier properties of organic coatings.In this study both deionized water and 3.5 wt% sodium chloride solution are chosen as the working fluids. The organic coatings are exposed to stationary immersion as well as the laminar flow with a variety of flow rates. The barrier properties of coatings are monitored inline by electrochemical impedance spectroscopy measurements. Equivalent circuit models are developed to interpret EIS spectra and to analyze the physical behavior of coatings as they are degrading. We find that the barrier properties of coatings decrease with the immersion time and the decrease is more substantial for flowing fluids at higher flow rates disregard of the composition of the working fluid. Different types of coatings respond differently to DI water and the sodium chloride solution for their degradation rates if immersed in a laminar flow.