해수분위기에서 스테인리스강 배관 소켓 용접부의 선택적 부식
Selective Corrosion of Socket Welds of Stainless Steel Pipes Under Seawater Atmosphere
1
조회
0
다운로드
2
인용
0
참고문헌
키워드
초록
Stainless steel has excellent corrosion resistance. The drawback is that pitting occurs easily due to the concentrationof chloride. In addition, corrosion of socket weld, which is structurally and chemically weaker than theother components of the pipe, occurs rapidly. Since these two phenomena overlap, pinhole leakage occursfrequently in the seawater pipe socket welds made of stainless steel at the power plants. To analyze thisspecific corrosion, a metallurgical analysis of the stainless steel socket welds, where the actual corrosionoccurred during the power plant operation, was performed. The micro-structure and chemical compositionof each socket weld were analyzed. In addition, selective corrosion of the specific micro-structure in a mixeddendrite structure comprising γ-austenite (gamma-phase iron) and δ-ferrite (iron at high temperature) wasinvestigated based on the characteristic micro-morphology and chemical composition of the corroded area. Finally, the different corrosion stages and characteristics of socket weld corrosion are summarized.
Abstract
Stainless steel has excellent corrosion resistance. The drawback is that pitting occurs easily due to the concentrationof chloride. In addition, corrosion of socket weld, which is structurally and chemically weaker than theother components of the pipe, occurs rapidly. Since these two phenomena overlap, pinhole leakage occursfrequently in the seawater pipe socket welds made of stainless steel at the power plants. To analyze thisspecific corrosion, a metallurgical analysis of the stainless steel socket welds, where the actual corrosionoccurred during the power plant operation, was performed. The micro-structure and chemical compositionof each socket weld were analyzed. In addition, selective corrosion of the specific micro-structure in a mixeddendrite structure comprising γ-austenite (gamma-phase iron) and δ-ferrite (iron at high temperature) wasinvestigated based on the characteristic micro-morphology and chemical composition of the corroded area. Finally, the different corrosion stages and characteristics of socket weld corrosion are summarized.
참고문헌 (13)
- K. I. Byun, , J. KWS, 17, pp.89~ (1999)
- T. Kim, , Proc. Korean Energy Society Conf., pp.21~ (2019), Korean Energy Society
- W. Kim, , Proc. KWJS, 131 (2013)
- Y. Choi, , Corros. Sci. Tech, 3, pp.216~ (2004)
- Gokul Obulan Subramanian, "Evaluation of the thermal aging of δ-ferrite in austenitic stainless steel welds by electrochemical analysis", Scientific Reports, 8(1) (2018), Springer Science and Business Media LLC[DOI]
- V. N. Rajakovic-Ognjanovic, , J. Serb. Chem. Soc, 76, pp.1027~ (2011)[DOI]
- ASME, "BPVC Section II-Materials-Part A, Ferrous Material Specification", ~ (2019)
- "CP-P1 4K-2, Construction Package", ~ (1991)
- ASME, "BPVC Section II-Materials- Part C, Specification for Welding Rod, Electrodes, and Filler Metals", ~ (2019)
- N. Suutala, "Ferritic-austenitic solidification mode in austenitic stainless steel welds", Metallurgical Transactions A, 11(5), pp.717~725 (1980), Springer Science and Business Media LLC[DOI]
- Jae-Won Park, "δ-Ferrite Behavior of Butt Weld Zone in Clad Steel Plates Depended on Holding Time of PWHT", Journal of the Korean Welding and Joining Society, 32(2), pp.29~36 (2014), The Korean Welding and Joining Society[DOI]
- J. C. Lippold, , Ph. D., pp.1978
- Armando M. Lago, "Short-term post-earthquake bus transit planning in Managua", Transportation, 5(2), pp.135~152 (1976), Springer Science and Business Media LLC[DOI]