• 제목/요약/키워드: chromium depletion

검색결과 22건 처리시간 0.016초

316계 스테인리스강과 소듐 냉각재와의 양립성 연구 (Compatibility Study between 316-series Stainless Steel and Sodium Coolant)

  • 김준환;김종만;차재은;김성호;이찬복
    • 대한금속재료학회지
    • /
    • 제48권5호
    • /
    • pp.410-416
    • /
    • 2010
  • Studies were carried out to establish the technology for sodium-clad compatibility and to analyze the compatibility behavior of the Sodium-cooled Fast Reactor (SFR) cladding material under a flowing sodium environment. The natural circulation facility caused by the thermal convection of the liquid sodium was constructed and the 316-series stainless steels were exposed at $650{^{\circ}C}$ liquid sodium for 1458 hours. The weight change and related microstructural change were analyzed. The results showed that the quasi-dynamic facility represented by the natural convection exhibited similar results compared to the conventional dynamic facility. Selective leaching and local depletion of the chromium, re-distribution of the carbide, and the decarburization process took place in the 316-series stainless steel under a flowing sodium environment. This process decreased as the sodium flowed along the channel, which was caused by the change in the dissolved oxygen and carbon activity in the liquid sodium.

오스테나이트계 중탄소 및 저탄소 스테인리스강의 입계부식 거동 분석 (Intergranular Corrosion Behavior of Medium and Low Carbon Austenitic Stainless Steel)

  • 원석연;김규빈;유영란;최승헌;김영식
    • Corrosion Science and Technology
    • /
    • 제21권3호
    • /
    • pp.230-241
    • /
    • 2022
  • Austenitic stainless steel has been widely used because of its good corrosion resistance and mechanical properties. However, intergranular corrosion can occur if the alloy is welded or aged. The objective of this study was to determine intergranular corrosion behaviors of austenitic medium carbon (0.05 wt%) and low carbon (0.02 wt%) stainless steel aged at several conditions. Alloys were evaluated according to ASTM A262 Practice A, ISO 12732 DL-EPR (double loop-electrochemical potentiokinetic reactivation) test, and ASTM A262 Practice C. The degree of sensitization and intergranular corrosion rate were obtained. The relationship between the degree of sensitization and the intergranular corrosion rate showed a very large fluctuation. Such behavior might be related to whether two-dimension tests or three-dimension tests were performed. On the other hand, regardless of carbon content of alloys, when the intergranular corrosion rate increased, the degree of sensitization also increased. However, the DL-EPR test showed a higher sensitivity than the Huey test for differentiating the intergranular corrosion property at a low intergranular corrosion rate, while the Huey test had a higher sensitivity than the DL-EPR test for distinguishing the intergranular corrosion property at a high intergranular corrosion rate.