Corrosion Science and Technology

The Corrosion Science Society of Korea (한국부식방식학회)
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Surface Appearance of Galvanized Steel with Outdoor Exposure Testing in Korea for 36 Months

36개월간 국내 옥외폭로시험에 따른 아연도강의 표면외관 변화

  • Kim, K.T. (Research Center for Energy and Clean Technology, School of Materials Science and Engineering, Andong National University) ;
  • Kim, Y.S. (Research Center for Energy and Clean Technology, School of Materials Science and Engineering, Andong National University)
  • 김기태 (안동대학교 신소재공학부 청정에너지소재기술연구센터) ;
  • 김영식 (안동대학교 신소재공학부 청정에너지소재기술연구센터)
  • Received : 2018.12.11
  • Accepted : 2018.12.21
  • Published : 2018.12.31
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Abstract

If galvanized steel is exposed to an outdoor environment, atmospheric corrosion will occur with time and red rust will form when the sacrificial protection capacity of zinc reaches its limit. With corrosion, the surface appearance of steel changes, and the properties of the exterior materials degrade. In this study, two kinds of galvanized steel, (GA and GI specimens) were subjected to an outdoor exposure test for 36 months in six regions of Korea. Chrominance (color, chroma, and brightness) and glossiness surface analyses were performed. The color change was not significant, regardless of the exposed area or the specimens tested. With increasing exposure times, the GA specimen became blackened by the formation of zinc oxide, and red coloration was increased by the formation of red rust. As the exposure time of GI specimen increased, the surface proceeded to blacken, but no red rust was formed and the color did not change significantly. Regardless of the outdoor exposure area or the specimen, longer exposure times led to lower glossiness, and this behavior appears to be influenced by the formation of zinc oxide.

Keywords

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Fig. 1 CIELAB color chart [6]

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Fig. 3 Effect of outdoor exposure time on the appearance by 3D microscope of GA specimens exposed in 6 sites of Korea

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Fig. 2 Fundamentals of gloss measurement [9]

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Fig. 4 Effect of outdoor exposure time on the appearance by 3D microscope of GI specimens exposed in 6 sites of Korea

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Fig. 5 Effect of outdoor exposure time on the chrominance of GA(a~c) and GI(a’~c’) specimens exposed in 6 sites of Korea; (a,a’) Δa*, (b,b’) Δb*, (c,c’) ΔL*

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Fig. 6 Color difference of galvanized steels with outdoor exposure time; (a) GA, (b) GI

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Fig. 7 Relationship between chrominance of GA(a, b) and GI(a’, b’) specimens and Zn content on the surface; (a, a’) Andong, (b, b’) Busan

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Fig. 8 Glossiness of GA (a, b) and GI (a’, b’) specimens with outdoor exposure time; (a, a’) Gloss (60°-L), (b, b’) ΔGloss (60°-L)

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Fig. 9 Relationship between the glossiness of GA(a, b) and GI(a’ b’) specimens and the composition on the surface; (a, a’) Andong, (b, b’) Busan

Table 1. National Bureau of Standard (NBS) Unit [7]

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References

  1. K. T. Kim and Y. S. Kim, Corros. Sci. Tech., 17, 231 (2018).
  2. E. Y. Cho, G. B. Gwon, D. H. Cho and J. Y. Kim, Corros. Sci. Tech., 12, 209 (2013). https://doi.org/10.14773/cst.2013.12.5.209
  3. R. Vera, E. Cruz, M. Bagnara, R. Araya, and R. Henriquez, Int. J. Electrochem. Sci., 13, 898 (2018).
  4. W. Wu, X. Cheng, H. Hou, B. Liu, and X. Li, Appl. Sur. Sci., 436, 80 (2018). https://doi.org/10.1016/j.apsusc.2017.12.018
  5. ISO 11664-4, Colorimetry - Part 4: CIE 1976 L*a*b* Colour space, ISO, Geneva, Switzerland (2008).
  6. S. Sharifzadeh, L. H. Clemmensen, C. Borggaard, S. Stoier, and B. K. Ersboll, Eng., Appl. Art. Intel., 27, 211 (2014). https://doi.org/10.1016/j.engappai.2013.09.004
  7. ISO 11664-6, Colorimetry - Part 6: CIEDE2000 Colour-difference formula, ISO, Geneva, Switzerland (2013).
  8. Nimeroff I. Colorimetry. National Bureau Standard Monograph (1968).
  9. KS L 2405, Method of Measurement for Specular Glossiness, KS (2011).
  10. ASTM D 523, Standard Test Method for Specular Gloss, ASTM (1995).