由微小缝隙模拟管线剥离覆盖层(涂层)下的局部电化学环境,用微电极技术测量了缝隙内局部电位及pH的分布,研究了缝口阴极保护电位、剥离区几何形状、溶液电导率等因素对剥离区内部局部环境及阴极保护水平的影响.结果表明,剥离区内电位降(电位梯度)主要集中在破损口附近,而剥离区深处接近自然腐蚀状态;剥离区内有效保护距离随缝口保护电位负移而增加,但缝口过保护并不能有效提高剥离区保护效果.阴极保护可使剥离区局部电化学环境pH升高、电导率增大.
参考文献
[1] | Toncre A C.On achieving polarization beneath unbonded pipe coatings[J].Materials Performance,1984:22-27. |
[2] | F. M. SONG;D. W. KIRK;J. W. GRAYDON;D. E. CORMACK;D. WONG .Corrosion Under Disbonded Coatings Having Cathodic Protection[J].Materials Performance,2003(9):24-26. |
[3] | Beavers J A;Thompson N G .Corrosion beneath disbonded pipeline coatings[J].Materials Performance,1997,36(04):13-19. |
[4] | Sabde G;Gan F;Chin D T .Cathodic protection of underground pipeline against crevice corrosion:are view[J].Journal of the Chinese Institute of Chemical Engineers,1993,24(06):417-429. |
[5] | 李正奉,毛旭辉,甘复兴.阴极保护下缝隙内的电位分布[J].中国腐蚀与防护学报,2000(03):129. |
[6] | Brousseau R;Qian S .Distribution of steady-state cathodic currents underneath a disbonded coating[J].Corrosion,1994,50(12):907-911. |
[7] | Gan F;Sun Z W;Sabde G et al.Cathodic protection to mitigate external corrosion of underground steel pipe beneath disbonded coating[J].Corrosion,1994,50(10):804-816. |
[8] | S. Y. Li;Y.G. Kim;Y.T. Kho .Statistical Approach to Corrosion under Disbonded Coating on Cathodically Protected Line Pipe Steel[J].Corrosion: The Journal of Science and Engineering,2004(11):1058-1071. |
[9] | Parkins R;Belhimer E;Blanchard W .Stress-corrosion cracking characteristics of a range of pipeline steels in carbonate-bicarbonate solution[J].Corrosion,1993,49(12):951-966. |
[10] | E.A. Charles;R.N. Parkins .Generation of Stress Corrosion Cracking Environments at Pipeline Surfaces[J].Corrosion: The Journal of Science and Engineering,1995(7):518-527. |
[11] | Wang M.;Yao S. .Carbonate-melt oxidized iridium wire for pH sensing[J].Electroanalysis,2003(20):1606-1615. |
[12] | Fessler R R;Markworth A J;Parkins R N .Cathodic protection levels under disbonded coatings[J].Corrosion,1983,39(01):20-25. |
[13] | Husock B;Wilson R .Potentials and hydrogen evolution on coated pipe[J].Materials Performance,1984,9:26-30. |
[14] | Perdomo J J;Song I .Chemical and electrochemical conditions on steel under disbonded coatings:the effect of applied potential,solution resistivity,crevice thickness and holiday size[J].Corrosion Science,2000,42(08):1389-1415. |
[15] | F. Kajiyama;K. Okamura .Evaluating cathodic protection reliability on steel pipe in microbially active soils[J].Corrosion: The Journal of Science and Engineering,1999(1):74-80. |
[16] | 闫茂成,翁永基.阴极保护管线破损涂层下高pH环境形成规律[J].中国腐蚀与防护学报,2004(02):95-99. |
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