Effect of Microstructures and Material Compositions on Blister Formation

摘要

One of the early failures of coating is blister. Here two different coatings were applied on various materials and microstructures. The formation of the blister, and its microstructural and material dependencies were evaluated. It is concluded that general organic coating forms more severe blisters than that of the metallic effect coating. General organic coating protects the samples by insulation film while metallic coating protects by acting as galvanic protection. Therefore, the failure modes are also different, namely blister and filiform corrosion. The dependencies on the microstructures and on material types also follow the insulation film concept and galvanic protection concept.