CAO Jingyi, XIONG Jinping, LI Shuibing, et al. Evaluation of protective performance of organic coatings by EIS parameters at high frequency zone[J]. CIESC Journal, 2008, (11): 2851-2856.
CAO Jingyi, XIONG Jinping, LI Shuibing, et al. Evaluation of protective performance of organic coatings by EIS parameters at high frequency zone[J]. CIESC Journal, 2008, (11): 2851-2856.DOI:
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 106Ω8226;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.