Corrosion Science and Technology

The Corrosion Science Society of Korea (한국부식방식학회)
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Optimal Electropolishing Condition of Austenitic Stainless Steel Specimens for Slow Strain Rate Tensile Testing

오스테나이트 스테인리스강 저속인장시험편의 최적 전해연마 특성

  • Min-Jae Choi (Materials Safety Technology Research Division, Korea Atomic Energy Research Institute) ;
  • Eun-Byeoul Jo (Materials Safety Technology Research Division, Korea Atomic Energy Research Institute) ;
  • Dong-Jin Kim (Materials Safety Technology Research Division, Korea Atomic Energy Research Institute)
  • 최민재 (한국원자력연구원 재료안전기술연구부) ;
  • 조은별 (한국원자력연구원 재료안전기술연구부) ;
  • 김동진 (한국원자력연구원 재료안전기술연구부)
  • Received : 2023.11.22
  • Accepted : 2023.12.12
  • Published : 2023.12.29
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Abstract

Irradiation-assisted stress corrosion cracking (IASCC) is one of the main degradation mechanisms of austenitic stainless steels, which are used as reactor internal materials. Slow strain rate testing (SSRT) has been widely applied to evaluate the IASCC initiation characteristics of proton-irradiated tensile specimens. Tensile specimens require low surface roughness for micro-crack observation, and electropolishing is the most important specimen pre-treatment process used for this. In this study, optimal electropolishing conditions were examined through analyzing results of polarization experiments and surface roughness measurements after electropolishing. Corrosion cell and electropolishing equipment were fabricated for polarization tests and electropolishing experiments using SSRT specimens. The experimental parameters were electropolishing time, current density, electrolyte temperature, and stirring speed. The optimal electropolishing conditions for SSRT tensile specimens made of type 316 stainless steel were evaluated as a polishing time of 180 seconds, a current density of 0.15 A/cm2, an electrolyte temperature of 60 ℃, and a stirring speed of 200 RPM.

Keywords

Acknowledgement

이 논문은 정부(과학기술정보통신부)의 재원으로 한국연구재단의 지원을 받아 수행된 연구임(RS-2022-00143718).

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