关键词:

电化学阻抗谱, 环氧涂层, 性能, 腐蚀, 快速测量

Abstract:

The failure processes of two epoxy coatings exposed in 3.5% NaCl solution and violet light were studied by electrochemical impedance spectrum (EIS) technology.The work was focused on the variations of phase angle at 10 kHz, relative dielectric constant and breakpoint frequency with the decline of coating performance.The results showed that the three parameters from high frequency range of EIS gave similar results and might reflect the variation of coating performance.When the phase angle at 10 kHz decreased to 40°, relative dielectric constant increased to 40, or the breakpoint frequency approached about 10 kHz, the coating resistances of the two epoxy coatings studied decreased to about 10⁶Ω•cm², and the coating performance was very low.Therefore, the parameters may be used as quick methods to evaluate the protective performance of the coatings.

Key words:

电化学阻抗谱, 环氧涂层, 性能, 腐蚀, 快速测量