CF8M 스테인리스 강 저주기 환경피로 실험의 주기적 변형률 경화 특성

다국어 초록 (Multilingual Abstract)

Low-cycle environmental fatigue tests of cast austenitic stainless steel CF8M at the condition of fatigue strain rate 0.04%/sec were conducted at the pressure and temperature, 15MPa, 315℃ of a operating pressurized water reactor (PWR). The used test rig was limited to install an extensometer at the gauge length of the cylindrical fatigue specimen inside a small autoclave. So the magnet type LVDT's were used to measure the fatigue displacement at the specimen shoulders inside the high temperature and high pressure water autoclave. However, the displacement and strain measured at the specimen shoulders is different from the one at the gauge length for the geometry and the cyclic strain hardening effect. Displacement of the fatigue specimen gauge length calculated by FEM (finite element method) used to modify the measured displacement and fatigue life at the shoulders. A series of low cycle fatigue life tests in air and PWR conditions simulating the cyclic strain hardening effect verified that the FEM modified fatigue life was well agreed with the simulating test results. The process and method developed in this study for the environmental fatigue test inside the small sized autoclave would be so useful to produce reliable environmental fatigue curves of CF8M stainless steel in pressurized water reactors.

목차 (Table of Contents)

• Abstract
• 1. 서론
• 2. 저주기 환경피로실험장치
• 3. 저주기 환경피로 실험
• 4. 실험결과 고찰
• 5. 결론
• 후기
• 참고문헌

참고문헌 (Reference)

1 "Standard Practice for Strain-Controlled Fatigue Testing. ASTM E 606-92"

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4 Jeong, I.S, "Low Cycle Fatigue Test of CF8M Cast Stainless Steel in PWR Environment" 2007

5 Bannantine, Julie A., "Fundamentals of Metal Fatigue Analysis" Prentice-Hall 40-87, 1990

6 Itatani, M., "Fatigue Crack Growth Curve for Austenitic Stainless Steels in BWR Environment" 123 : 2001

7 Jang, C.H, "Environmental Fatigue Tests in the Deaerated High Temperature Water" 2007

8 Jeong, I.S., "Environmental Fatigue Crack Propagation Behavior of Cast Stainless Steels under PWR Condition" 297 : 968-973, 2005

9 Gerber, D.A., ""Evaluation of Environmental Fatigue Effects for a Westinghouse Nuclear Power Plant," EPRI TR-110043"

10 Garud, Y.S., ""Corrosion Fatigue of Water-Touched Pressure Retaining Components in Power Plants," EPRI TR-106696"