해양환경안전학회지 (Journal of the Korean Society of Marine Environment & Safety)

  • 제27권1호
  • /
  • Pages.187-192
  • /
  • 2021
  • /
  • 1229-3431(pISSN)
  • /
  • 2287-3341(eISSN)
해양환경안전학회 (The Korean Society of Marine Environment and safety)
권호 표지
DOI QR코드

DOI QR Code

Inconel 625 용사코팅된 절탄기 핀튜브의 전기화학적 내식성 분석

Analysis of Electrochemical Corrosion Resistance of Inconel 625 Thermal Spray Coated Fin Tube of Economizer

  • 박일초 (목포해양대학교 승선실습과정부) ;
  • 한민수 (목포해양대학교 기관시스템공학부)
  • Park, Il-Cho (Division of Cadet Training, Mokpo National Maritime University) ;
  • Han, Min-Su (Division of Marine Engineering, Mokpo National Maritime University)
  • 투고 : 2020.12.14
  • 심사 : 2021.02.25
  • 발행 : 2021.02.28
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

본 연구는 절탄기 튜브의 저온부식 손상을 방지하기 위해 Inconel 625 용사재료를 활용하여 아크 열용사 코팅기술 적용 후 실링처리를 실시하였다. 용사코팅(TSC) 층의 내식성 분석을 위해 0.5 wt% 황산 수용액에서 다양한 전기화학적 실험을 진행하였다. 양극분극 실험 후에는 주사전자현미경과 EDS 성분분석을 통해 부식 손상 정도를 파악하였다. 자연전위 계측 시 TSC+실링처리(TSC+Sealing)의 안정적인 전위 형성을 통해 실링처리 효과를 확인하였다. 양극분극 실험 결과 TSC와 TSC+Sealing에서 부동태 영역이 확인되었으며, 부식 손상 역시 관찰되지 않아 내식성이 개선되었다. 더불어 타펠분석에 의해 산출된 부식전위와 부식전류밀도 분석 결과 TSC+Sealing의 내식성이 가장 우수하게 나타났다.

In this study, Inconel 625 was used as a thermal spray material to prevent dew point corrosion damage to the economizer tube, and sealing treatment was performed after applying the arc thermal spray coating technology. Various electrochemical experiments were conducted in the 0.5 wt% sulfuric acid solution to analyze the corrosion resistance of the thermal spray coating (TSC) layer. After the anodic polarization experiment, the degree of corrosion damage was determined through a scanning electron microscope and EDS component analysis. When measuring the open circuit potential, the effect of the sealing treatment was confirmed through stable potential formation of the TSC+sealing treatment (TSC+Sealing). As a result of the anodic polarization experiment, the passivation region was confirmed in TSC and TSC+Sealing, and corrosion resistance was improved as no corrosion damage was observed. In addition, the corrosion resistance of TSC+Sealing was the best when analyzing the corrosion potential and corrosion current density calculated by Tafel analysis.

키워드

참고문헌

  1. Basu, S. and A. K. Debnath(2014), Power Plant Instrumentation and Control Handbook: A Guide to Thermal Power Plants, Academic Press.
  2. Davis, J. R.(2004), Handbook of Thermal Spray Technology, ASM international, pp. 3-13.
  3. Denpo, K. and H. Ogawa(1997), Passivity of Corrosionresistant Alloys in Environments Containing Chloride and Hydrogen Sulfide, Corrosion, Vol. 53, No. 9, pp. 718-723. https://doi.org/10.5006/1.3290305
  4. Ding, Q., X. F. Tang, and Z. G. Yang(2017), Failure Analysis on Abnormal Corrosion of Economizer Tubes in a Waste Heat Boiler, Engineering Failure Analysis, Vol. 73, pp. 129-138. https://doi.org/10.1016/j.engfailanal.2016.12.011
  5. Ganapathy, V.(1989), Cold End Corrosion: Causes and Cures, Hydrocarbon Processing, p. 57.
  6. Gong, Y. and Z. G. Yang(2011), Corrosion Evaluation of One Dry Desulfurization Equipment-Circulating Fluidized Bed Boiler, Materials & Design, Vol. 32, No. 2, pp. 671-681. https://doi.org/10.1016/j.matdes.2010.08.003
  7. Lugscheider, E. and T. Weber(1990), Plasma Spraying-An Innovative Coating Technique: Process Variants and Applications, IEEE Transactions on Plasma Science, Vol. 18, No. 6, pp. 968-973. https://doi.org/10.1109/27.61511
  8. Malek, M. H. A., N. H. Saad, S. K. Abas, and N. M. Shah(2013), Thermal Arc Spray Overview, In IOP Conference Series: Materials Science and Engineering, Vol. 46, No. 1, https://doi.org/10.1088/1757-899X/46/1/012028.
  9. Moakhar, R. S., M. Mehdipour, M. Ghorbani, M. Mohebali, and B. Koohbor(2013), Investigations of the Failure in Boilers Economizer Tubes Used in Power Plants, Journal of Materials Engineering and Performance, Vol. 22, No. 9, pp. 2691-2697. https://doi.org/10.1007/s11665-013-0567-2
  10. Park, I. C. and S. J. Kim(2016), Electrochemical Characteristics of Arc Thermal Sprayed Inconel 625 Coating on SS400 Steel in Seawater, Journal of the Korean institute of surface engineering, Vol. 49, No. 2, pp. 172-177. https://doi.org/10.5695/JKISE.2016.49.2.172
  11. Perry, R. H. and D. W. Green(1997), Perrys Chemical Engineers Handbook, 7th ed., McGraw-Hill, New York.