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Estimation of Fracture Resistance Curves of Nuclear Materials Using Small Punch Specimen

소형펀치 시편을 이용한 원자력 재료의 파괴저항곡선 예측

  • 장윤석 (성균관대학교 기계공학부) ;
  • 김종민 (성균관대학교 기계공학부) ;
  • 최재붕 (성균관대학교 기계공학부) ;
  • 김민철 (한국원자력연구소 원자력재료기술개발부) ;
  • 이봉상 (한국원자력연구소 원자력재료기술개발부) ;
  • 김영진 (성균관대학교 기계공학부)
  • Published : 2007.01.01

Abstract

Elastic-plastic fracture mechanics is popularly used for integrity evaluation of major components, however, it is not easy to extract standard specimens from operating facility. This paper examines how ductile fracture toughness is characterized by a small punch testing technique in conjunction with finite element analyses incorporating a damage model. At first, micro-mechanical parameters constituting Rousselier model are calibrated for typical nuclear materials using both estimated and experimental load-displacement (P-$\delta$) curves of miniaturized specimens. Then, fracture resistance (J-R) curves of relatively larger standard CT specimens are predicted by finite element analyses employing the calibrated parameters and compared with corresponding experimental ones. It was proven that estimated results by the proposed method using small punch specimen is promising and might be used as a useful tool for ductile crack growth evaluation.

Keywords

Damage Model;Ductile Fracture;Fracture Resistance Curve;Small Punch Specimen

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