극한지용 고장력강의 평균 응력 삼축비 및 평균 정규 로드 파라메터를 고려한 3차원 파단 변형률 평면 개발: 제2부 파단 변형률 평면의 정식화
Development of Three-Dimensional Fracture Strain Surface in Average Stress Triaxiaility and Average Normalized Lode Parameter Domain for Arctic High Tensile Steel: Part II Formulation of Fracture Strain Surface
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An extended study was conducted on the fracture criterion by Choung et al. (2011; 2012) and Choung and Nam (2013), and the results are presented in two parts. The theoretical background of the fracture and the results of new experimental studies were reported in Part I, and three-dimensional fracture surface formulations and verifications are reported in Part II. How the corrected true stress can be processed from the extrapolated true stress is first introduced. Numerical simulations using the corrected true stress were conducted for pure shear, shear-tension, and pure compression tests. The numerical results perfectly coincided with test results, except for the pure shear simulations, where volume locking appeared to prevent a load reduction. The average stress triaxialities, average normalized lode parameters, and equivalent plastic strain at fracture initiation were extracted from numerical simulations to formulate a new three-dimensional fracture strain surface. A series of extra tests with asymmetric notch specimens was performed to check the validity of the newly developed fracture strain surface. Then, a new user-subroutine was developed to calculate and transfer the two fracture parameters to commercial finite element code. Simulation results based on the user-subroutine were in good agreement with the test results.
Abstract
An extended study was conducted on the fracture criterion by Choung et al. (2011; 2012) and Choung and Nam (2013), and the results are presented in two parts. The theoretical background of the fracture and the results of new experimental studies were reported in Part I, and three-dimensional fracture surface formulations and verifications are reported in Part II. How the corrected true stress can be processed from the extrapolated true stress is first introduced. Numerical simulations using the corrected true stress were conducted for pure shear, shear-tension, and pure compression tests. The numerical results perfectly coincided with test results, except for the pure shear simulations, where volume locking appeared to prevent a load reduction. The average stress triaxialities, average normalized lode parameters, and equivalent plastic strain at fracture initiation were extracted from numerical simulations to formulate a new three-dimensional fracture strain surface. A series of extra tests with asymmetric notch specimens was performed to check the validity of the newly developed fracture strain surface. Then, a new user-subroutine was developed to calculate and transfer the two fracture parameters to commercial finite element code. Simulation results based on the user-subroutine were in good agreement with the test results.
참고문헌 (9)
- Altair, "HyperWorks 12. 0 User Manual" (2013), Altair
- Bai, Y., "A New Model of Metal Plasticity and Fracture with Pressure and Lode Dependence", International Journal of Plasticity, 24(6), pp.1071~1096 (2008)
- Choung, J., "Comparative Studies of Fracture Models for Marine Structural Steels", Ocean Engineering, 36(15), pp.1164~1174 (2009)
- 정준모, "조선 해양 구조물용 강재의 소성 및 파단 특성 III: 파단 변형률에 관한 실험적 연구", 한국해양공학회지, 25(3), pp.53~65 (2011), 한국해양공학회
- Choung, J., "Estimation of Failure Strain of EH36 High Strength Marine Structural Steel Using Average Stress Triaxiality", Marine Structures, 29(1), pp.1~21 (2012)
- 정준모, "저온용 고장력강(EH36)의 평균 응력 삼축비에 따른 파단 변형률 정식화", 한국해양공학회지, 27(2), pp.19~26 (2013), 한국해양공학회
- 정준모, "상용 유한요소코드 사용자-서브루틴을 이용한 저온용 고장력강 (EH36)의 파단 시뮬레이션", 한국해양공학회지, 28(1), pp.34~46 (2014), 한국해양공학회
- Choung, J., "Failure Strain Formulation Via Average Stress Triaxiality of an High Strength Steel for Arctic Structures", Ocean Engineering, 91, pp.218~226 (2014)
- Simulia, "Abaqus User Manual" (2008), Silumia