Evaluation of the Fracture Toughness Transition Characteristics of RPV Steels Based on the ASTM Master Curve Method Using Small Specimens

소형시험편의 Master Curve 방법을 이용한 원자로 압력용기강의 파괴인성 천이특성평가

Yang, Won-Jon;Heo, Mu-Yeong;Kim, Ju-Hak;Lee, Bong-Sang;Hong, Jun-Hwa

  • Published : 2000.02.01


Fracture toughness of five different reactor pressure vessel steels was characterized in the transition temperature region by the ASTM E1921-97 standard method using Charpy-sized small specimens. T he predominant fracture mode of the tested steels was transgranular cleavage in the test conditions. A statistical analysis based on the Weibull distribution was applied to the interpretation of the scattered fracture toughness data. The size-dependence of the measured fracture toughness values was also well predicted by means of the Weibull probabilistic analysis. The measured fracture toughness transition curves followed the temperature-dependence of the ASTM master curve within the expected scatter bands. Therefore, the fracture toughness characteristics in the transition region could be described by a single parameter, so-called the reference temperature (T。), for a given steel. The determined reference temperatures of the tested materials could not be correlated with the conventional index temperatures from Charpy impact tests.


PCCv(Pre-Cracked Charpy Specimen;Reference Temperature;Transitionn Region;Three Point Bend Test;Cleavage Fracture;RPV Steel


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