Determination of optimum protection potential for cathodic protection of offshore wind-turbine-tower steel substructure by using potentiostatic method

정전위법에 의한 해상풍력 타워 구조물용 강재의 음극방식을 위한 최적방식전위 결정

  • Lee, Jung-Hyung (Dongnam Regional Division, Korea Institute of Industrial Technology) ;
  • Jung, Kwang-hu (Division of Marine Engineering, Mokpo National Maritime University) ;
  • Park, Jae-Cheul (Machinery Technology Research Team) ;
  • Kim, Seong-Jong (Division of Marine Engineering, Mokpo National Maritime University)
  • Received : 2016.12.19
  • Accepted : 2017.01.26
  • Published : 2017.03.31


In this study, electrochemical methods were used to determine the optimum protection potential of S355ML steel for the cathodic protection of offshore wind-turbine-tower substructures. The results of potentiodynamic polarization experiments indicated that the anodic polarization curve did not represent a passivation behavior, while under the cathodic polarization concentration, polarization was observed due to the reduction of dissolved oxygen, followed by activation polarization by hydrogen evolution as the potential shifted towards the active direction. The concentration polarization region was found to be located between approximately -0.72 V and -1.0 V, and this potential range is considered to be the potential range for cathodic protection using the impressed current cathodic protection method. The results of the potentiostatic experiments at various potentials revealed that varying current density tended to become stable with time. Surface characterization after the potentiostatic experiment for 1200 s, by using a scanning electron microscope and a 3D analysis microscope confirmed that corrosion damage occurred as a result of anodic dissolution under an anodic polarization potential range of 0 to -0.50 V, which corresponds to anodic polarization. Under potentials corresponding to cathodic polarization, however, a relatively intact surface was observed with the formation of calcareous deposits. As a result, the potential range between -0.8 V and -1.0 V, which corresponds to the concentration polarization region, was determined to be the optimum potential region for impressed current cathodic protection of S355ML steel.


Grant : 해상 풍력 구조물의 설계수명 확보를 위한 최적 부식관리기술 개발

Supported by : 한국에너지기술평가원(KETEP)


  1. S. P. Breton and G. Moe, "Status, plans and technologies for offshore wind turbines in Europe and North America," Renewable Energy, vol. 34, no. 3, pp. 646-654, 2009.
  2. B. S. Hwang, J. H. Lee, and D. T. Yoo, "The development status of offshore wind farm in Korea," Journal of Korean Society of Steel Construction, vol. 23, no. 1, pp. 7-11, 2011 (in Korean).
  3. C. Perez-Collazo, D. Greaves, and G. Iglesias, "A review of combined wave and offshore wind energy," Renewable Sustainable Energy Reviews, vol. 42, pp. 141-153, 2015.
  4. K. K. Baek, "Corrosion and protection of ship hull and marine structure(I)," Corrosion and Protection, vol. 3, no. 1, pp. 28-42, 2004 (in Korean).
  5. S. Touzain, Q. Le Thu, and G. Bonnet, "Evaluation of thick organic coatings degradation in seawater using cathodic protection and thermally accelerated tests," Progress in Organic Coatings, vol. 52, no. 4, pp. 311-319, 2005.
  6. M. S. Han, S. Ko, S. H. Kim, S. K. Jang, and S. J. Kim, "Optimization of corrosion protection potential for stress corrosion cracking and hydrogen embrittlement of 5083-H112 alloy in seawater," Metals and Materials International, vol. 14, no. 2, pp. 203-211, 2008.
  7. M. Cabrini, S. Lorenzi, P. Marcassoli, and T. Pastore, "Hydrogen embrittlement behavior of HSLA line pipe steel under cathodic protection," Corrosion Reviews, vol. 29, no. 5-6, pp. 261-274, 2011.
  8. Det Norske Veritas AS, Design of Offshore Wind Turbine Structures, Norway, DNV-OS-J101, May, 2014.
  9. S. C. Dexter, "Role of microfouling organisms in marine corrosion," Biofouling, vol. 7, pp. 97-127, 1993.
  10. D. A. Jones, Passivity, Principles and Prevention of Corrosion, 2nd Edition, Prentice Hall, 1996.
  11. W. H. Hartt, C. H. Culberson, and S. W. Smith, "Calcareous deposits on metal surfaces in seawater-a critical review," Corrosion, vol. 40, no. 11, pp. 609-618, 1984.
  12. C. S. Lee, J. Kang, and M. H. Lee, "Properties analysis of environment friendly calcareous deposit films electrodeposited at various temperature conditions in natural seawater," Journal of the Korean Society of Marine Engineering, vol. 39, no. 7, pp. 779-785, 2015 (in Korean).
  13. C. Deslouis, D. Festy, O. Gil, G. Rius, S. Touzain, and B. Tribollet, "Characterization of calcareous deposits in artificial sea water by impedance techniques-I. Deposit of $CaCO_3$ without $Mg(OH)_2$," Electrochimica Acta, vol. 43, no. 12, pp. 1891-1901, 1998.