Journal of Welding and Joining
- Volume 15 Issue 5
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- Pages.124-133
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- 1997
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- 2466-2232(pISSN)
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- 2466-2100(eISSN)
A study of corrosion of welded bridge steel SWS400 in the acid-rain environment
산성비 분위기에서 교량용 강재 SWS400의 용접부 부식에 관한 연구
Abstract
Corrosion behavior of welded SWS400 steel used for bridges was studied in a range of the acid-rain environment using immersion, potentiodynamic polartization, polarization resistance, and galvanic corrosion tests. The SWS400 steel exhibited active corrosion behavior in the range of acid-rain environment, i.e. no passivation. As the results of immersion corrosion test, Tafel extrapolation method, and polarization resistance measurement, the average corrosion rats of the steels were 0.31-0.72 mm/year in the pH of 4-5, and 0.17 mm/yera in the pH 6, respectively. The steel showed a resistance to corrosion in the pH 6. The observed active behavior of SWS400 steel in chloride-containing environment indicated that the chloride ions exerts a detrimental influence on the formation of passive films. Galvanic corrosion was observed between the weld and the base metals because the weld is anodic to the base metal.
Keywords