Effects of compressive damage on the corrosion protection performance of offshore wind power coating systems

Abstract

Damage to multilayer organic coating systems due to compressive loads can deteriorate the corrosion protection performance of the coatings under offshore exposure. The contribution is concerned with statistical investigations into the effects of load-based and coating-based factors on the protection performance of different coating systems. Accelerated cyclic laboratory tests (ISO 12944-9) were performed on four multilayer coating systems, and the results were statistically analyzed. Results of analysis of variance investigations revealed that the effects on the anticorrosive performance of the coatings (anticorrosive effect [AE]) were dominated by coating-based factors, namely coating system and total dry film thickness. These factors could explain 86% of all effects. Coating system was the only extremely significant factor. Load-based factors did not deliver notable effects (5%). Except for the contact stiffness, these factors were insignificant. The load intensity was insignificant for all target parameters (blistering, delamination, AE). Coating regions, plastically deformed during the compression tests, did not lead to a reduction in the protection performance.