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| EFFECT OF SOLUTION STATE ON CATHODIC POLARIZATION BEHAVIOR OF Q345 STEEL BENEATH SIMULATED DISBONDED COATING |
| WU Zhibin, WEI Yinghua, LI Jing, SUN Chao |
| State Key Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 |
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Abstract Potential and current distributions in a cathodically polarized crevice between a simulated disbonded coating and segmented Q345 steels were measured in this paper. The effects of agitation, oxygen concentration and pH value of initial solution on cathodic polarization behavior were studied. The results showed that agitation forced the oxygen in bulk solution to enter the crevice, thus degrading cathodic polarization level of Q345 steels in crevice. In low conductivity solution, agitation caused oxygen concentration cells in crevice, and aggravated corrosion at the rear of crevice. The oxygen concentration and initial solution pH had little influence on the final cathodic polarization level of Q345 steels beneath the simulated disbonded coating.
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Received: 09 October 2011
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Corresponding Authors:
WEI Yinghua
E-mail: yhwei@imr.ac.cn
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