상온과 343℃에서 Alloy 690TT 증기발생기 전열관의 인장물성치 평가

국문 초록 (Abstract)

본 논문에서는 상온과 원전 설계온도에서 증기발생기 전열관의 축방향과 원주방향 응력-변형률 거동과 인장물성치를 파악하기 위해서, 튜브 시편과 링 시편을 이용하여 상온과 343℃에서 Alloy 690TT전열관에 대한 인장시험을 수행하였다. 축방향 인장시험 결과 상온과 343℃에서 모두 항복점 현상이 관찰되었으며, 343℃에서는 Serration이 관찰되었다. 축방향과 원주방향 모두 상온에 비해 343℃에서 강도는 감소하였으나 연신율은 거의 변화가 없었다. 343℃에서 가공경화율은 상온에 비해 약간 감소하였으나, 가공경화 거동의 변화는 없었다. 시험 온도에 관계없이 축방향에 비해 원주방향의 항복강도와 인장강도가 약 5~10% 정도 낮았다. 시편 방향에 관계없이 상온 대비 343℃에서 Alloy 690TT 전열관의 항복강도와 인장강도 감소는 ASME Sec.II의 온도 보정계수에 의해 예측된 것보다 큰 것으로 확인되었다.

다국어 초록 (Multilingual Abstract)

This study conducted tensile tests on an Alloy 690TT tube at room temperature (RT) and at 343°C using tube- and ring-type specimens to investigate the stress-strain behavior and tensile properties of a steam generator (SG) tube in the axial and circumferential directions at RT and at the design temperature of a nuclear power plant (NPP). The results of the axial tensile test showed that yield point phenomena appeared at both RT and 343°C, and serrated flow in the stress?strain curve appeared at 343°C. Yield and tensile strengths for both directions were clearly lower at 343°C compared to RT; however, the elongations were approximately the same at both test temperatures. Regardless of the test temperature, the strengths in the circumferential direction were lower by approximately 5∼10 % than those in the axial direction. In addition, the test data revealed that the reduction in the yield and tensile strengths of the Alloy 690TT SG tube with the test temperature was more significant than that estimated by the temperature correction factor of ASME Sec.II.

목차 (Table of Contents)

• 초록
• Abstract
• 1. 서론
• 2. 재료 및 시험절차
• 3. 시험 결과 및 토의
• 4. 결론
• 참고문헌(References)

참고문헌 (Reference)

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