J-R Curve Characterization by Load Ratio Analysis and Unloading Compliance Method for SA508 C-3 steel

J. Ocean Eng. Technol. 1998;12(1):65-75.

SA508-3재의 제하컴플라이언스법과 하중비해석을 이용한 파괴저항곡선 평가

임만배,차귀준,윤한기,안원기

동아대 생산기술연구소,동명전문대,동의대학교,동아대학원

Keywords: Unloading Compliance Method, Load Ratio Analysis, J-R Curve, Load-Displacement Curve, Temperature effect

핵심용어: 제하컴플라이언스법, 하중비해석, 파괴저항곡선, 하중-변위선도, 온도영향

Abstract

The fracture resistance curve is one of most important and design techniques employed in nuclear pressure vessel structures. This study is to evaluate the J-R curve characteristics for the SA508C-3 by the unloading compliance method and load rato analysis. The effect of strain aging for the exponential correlation of the J-R curve in this metal are investigated at room temperature, 20$0^{circ}C$ and 30$0^{circ}C$. The load ratio analysis method can evaluate the J-R curve by using the simple tension load-displacement curve only without the repeat of the unloading and loading. Therefore, the analysis by the proposed load ratio method has a merit, in comparison with the unloading compliance method, which can measure the crack length without the precision measurement equipment.