A method of Determination of Fracture Toughness of Reactor Pressure Vessel Steel by J Integral

J. Ocean Eng. Technol. 1995;9(1):111-119.

J적분을 이용한 원자력 압력용기강의 파괴인성치의 결정

오세욱,임만배,김진선

동아대학교 기계공학과,동아대학교 기계공학과,한국중공업 원자력 설계실

Keywords: Fracture toughness, Reactor Pressure Steel, J-integral, Elastic-Plastic Fracture Resistance Curve, Blunting Line, Unloading Compliance, Apparent Negative Crack Growth

핵심용어: 파괴인성, 원자력 압력용 기강, J적분, 탄소성 파괴 저항곡선, 둔화직선, 제하 컴플라이언스, 균열길이 감소 현상

Abstract

The elastic-plastic fracture toughness($J_{IC}$) and fracture resistance (J-R curve) of SA508-3 alloy steel used for nuclear reactor pressure vessel are investigated by using CT-type specimens. Fracture toughness tests are conducted by unloading compliance method and multiple specimen method at room temperature, -2$0^{circ}C$ and 20$0^{circ}C$. The apparent negative crack growth phenomenon which usually arises in partial unloading compliance test is well known. The negative crack growth phenomenon in determining J sub(IC) or J-R cure from partial unloading compliance experiments may be eliminated by the offset technique. In this study, the evaluation of $J_{IC}$ multiple specimen method recommended by the JSME gives the most reliable results by using half-size CT(similar-type) specimens.