Impedance-based multi-parameter evaluation of waterborne eco-coatings under wet-heat aging

In order to verify the feasibility of using environmentally friendly waterborne coatings to replace traditional solvent-based coatings in the power industry, this study compares the corrosion performance of waterborne eco-coatings, heavy anti-corrosion coating and ambient solvent-based coatings in hot and humid environments. The study used Spearman correlation analysis to deeply explore the changing law of coating performance with wet heat aging and its internal correlation. The test results show that the three coatings show good aging resistance under humid heat conditions, but the correlation between the performance indicators is different. The low frequency impedance modulus, as the core index, has a good correlation with other performance indexes, which can effectively reflect the comprehensive impermeability performance of the coatings. Based on this, this paper proposes a comprehensive evaluation system based on the low-frequency impedance modulus value, combined with the glossiness loss rate, hardness and adhesion and other parameters, which provides a scientific basis for the evaluation of the coating performance in the hot and humid environment.