Journal of the Korean institute of surface engineering (한국표면공학회지)

The Korean Institute of Surface Engineering (한국표면공학회)
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A Study on Relationship between Corrosion Characteristics and Salt Concentration of Anti-corrosive Paint

방청도료의 부식특성과 염분농도의 상관관계에 관한 연구

  • Moon, Kyung-Man (Dept. of Marine Equipment Engineering, Korea Maritime and Ocean University) ;
  • Lee, Myeong-Woo (Dept. of Marine Equipment Engineering, Korea Maritime and Ocean University) ;
  • Lee, Myeong-Hoon (Dept. of Marine Engineering, Korea Maritime and Ocean University) ;
  • Kim, Hye-Min (Dept. of Marine Engineering, Korea Maritime and Ocean University) ;
  • Baek, Tae-Sil (Department of steel industry, Pohang College)
  • 문경만 (한국해양대학교 공과대학 조선기자재공학부) ;
  • 이명우 (한국해양대학교 공과대학 조선기자재공학부) ;
  • 이명훈 (한국해양대학교 해사대학 기관공학부) ;
  • 김혜민 (한국해양대학교 해사대학 기관공학부) ;
  • 백태실 (포항대학교 제철산업과)
  • Received : 2018.03.23
  • Accepted : 2018.04.30
  • Published : 2018.04.30
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Abstract

Recently, many types of constructional steels have been often exposed to under severe corrosive environments due to acid rain with increasing environmental contamination. In order to inhibit their corrosion in severe corrosive environments, a painting method has been widely applied to numerous constructional steels of land as well as marine. Therefore, development of paint having a good quality of corrosion resistance is considered to be very important. In this study, four types of anti-corrosive paints (AP: Phenol epoxy, AC: Ceramic epoxy, AT: Coal tar epoxy, AH: High solid epoxy) were coated to the specimens, and then, were immerged in various salt solutions (0.1, 0.3, 3, 6, 9 and 15% NaCl solutions) for 11 days. And, the corrosion resistance of these samples by effect of osmotic pressure with salt concentration was investigated with electrochemical methods such as measurement of corrosion potential, impedance and corrosion current density. The corrosion current densities of all samples (AC, AT and AH) submerged in 3% NaCl solution exhibited the smallest values compared to other salt solutions. However, in the case of lower values of salt solutions than 3% NaCl solution, the corrosion current density increased again because it makes easier for water, dissolved oxygen and chloride ion etc. to invade toward inner side of coating film due to increasing of the osmotic pressure than 3% NaCl solution, but in the case of higher values of salt solutions than 3% NaCl solution, the coating film is easily deteriorated due to high concentration of chloride ion rather than the osmotic pressure, which resulted in increasing the corrosion current density. In particular, the AC sample indicated the best corrosion resistance in 6% NaCl solution compared to other samples. Consequently, it is considered that the corrosion mechanism of the coated steel plate is completely different from bare steel plate, and the corrosion resistance of coating film by osmotic pressure and chloride ion depend on various types of epoxy of paint in NaCl solution.

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References

  1. P. Cicognami, Application of the Boundary-Element Method to Offshore Cathodic Protection Modeling, J. of .Electro. Soc. 137 (1990) 1689-1695. https://doi.org/10.1149/1.2086771
  2. K. G. Compton, Factor Involved in Corrosion of Lead Cable Sheath, CORRO. 17 (1961) 115-118.
  3. P. O. Gartland, E. Bardel, R.E. Andresen, and R. Johnson, Effect of Flow on the Cathodic Protection of a Steel Cylinder in Sea Water, CORRO. 40 (1984) 127-133. https://doi.org/10.5006/1.3593927
  4. M. Hiramatsi, M. Hino and T. Omi, Current Trend in Development of Corrosion Protective Plating, Zairo-to-Kankyo, 45 (1996) 33-41. https://doi.org/10.3323/jcorr1991.45.33
  5. D. A. Jones and N. R. Nair, .Electrochemical Corrosion Studies on Zinc- Coated Steel, CORRO. 41 (1985) 357-362. https://doi.org/10.5006/1.3582017
  6. J. Newman, Cathodic Protection with Parrel Cylinders, J. of Electro. Soc. 130 (1991) 3554-3559.
  7. U. Steinsmo and E. Bardal, Factors Limiting the Cathodic Current on Painted Steel, J. of Electro. Soc. 136 (1989) 3588-3594. https://doi.org/10.1149/1.2096514
  8. U. Steinsmo, J.I. Ska, and E. Bardal, The Effect of the Dry Film Thickness, Temperature, and Electrolyte on the Cathodic Current of Painted Steel, J. of Electro. .Soc. 136 (1989) 3383-3587.
  9. Report of Corrosion Damage Research, Japan Soc. of Corro. Control Tec. (1977) 15.
  10. J. B. Allen, R. F Harry, Electrochemical Method, Fundamlnals and Applications, (1980) 323-324.
  11. J. B. Allen, R. F Harry, Electrochemical Method, Fundamlnals and Applications, (1980) 351-352.
  12. D. C. Grahame, Mathematical Theory of the Faradaic Admittance (Pseudocapacity and Polarization Resistance), J. of Electro. Soc. 99 (1952) 370-385. https://doi.org/10.1149/1.2779638
  13. K. M. Moon, Practical Electrochemistry, Hyosung Publishing Co. (1999) 177.