PSI - Issue 13

Gyo Geun Youn et al. / Procedia Structural Integrity 13 (2018) 1305–1311 Author name / Structural Integrity Procedia 00 (2018) 000 – 000

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Fig. 10. Crack growth behavior of unaged and aged CF8A in pipe system under cyclic loading

5. Conclusion From the result of virtual pipe test, it can be concluded that the crack growth rate of unaged and aged CF8A becomes similar when loading type is changed from monotonic to cyclic loading condition. Also, from the virtual pipe system test, it can be concluded that the crack growth of unaged and aged CF8A shows bigger difference when the size of crack gets bigger. Acknowledgements This research was supported by National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning. (NRF-2017R1A2B2009759) References Peckner, D. and Bernstein, I. M., 1977, “Handbook of Stainless Steels,” McGraw-Hill, New York. Chung, H. M. and Chopra, O. K., 1987, “Kinetics and Mechanism of Thermal Aging Embrittlement of Duplex Stainless Steels,” Argonne National Lab ., IL, USA. Chung, H. M. and Leax, T. R., 1990, “Embrittlement of laboratory and reactor aged CF3, CF8, and CF8M duplex stainless steels,” Mat. Sci. Tech. , 6, 249–262. G. G. Youn, H. S. Nam, Y. J. Kim and J. W. Kim, 2018, “Numerical simulation of thermal ageing effect on fracture behaviour for CF8A cast stainless steels under very low cyclic loading condition”, ECF22, paper 385 McClintock, F. A., 1968, “A criterion for ductile fracture by the growth of holes,” J. Appl. Mech. , 35, 363–371. Rice, J. R. and Tracey, D. M., 1969, “On the ductile enlargement of voids in triaxial stress fields,” J. Mech. Phys. Solids. , 17, 201–217. Hancock, J. W. and Mackenzie, A. C., 1976, “On the mechanisms of ductile failure in high-strength steels subjected to multi-axial stress-states,” J. Mech. Phys. Solids ., 24, 147–160. Johnson, G. R. and Cook, W. H., 1985, “Fracture characteristics of three metals subjected to various strains, strain rates, temperatures and pressures,” Eng. Fract. Mech ., 21, 31–48. Chopra, O. K. and Sharck, W. J., 1994, “Assessment of Thermal Embrittlement of Cast Stainless steel,” NUREG/CR-6177, ANL-94/2, Nuclear Regulatory Commission , Washington, DC, USA. Chopra, O. K. and Sather, A., 1990, “Initial Assessment of the Mechanisms and Significance of Low-Temperature Embrittlement of Cast Stainless Steels in LWR Systems,” NUREG/CR-5385 , ANL-89/17, Nuclear Regulatory Commission, Washington, DC, USA. Chopra, O. K., 1994, “Estimation of Fracture Toughness of Cast Stainless Steels During Thermal Aging in LWR Systems-Revision 1,” NUREG/CR 4513, ANL-93/22, Nuclear Regulatory Commission , Washington, DC, USA. Nam, H. S. Lee. J. M. Kim. Y. J. and Kim. J. W. 2018, “Numerical ductile fracture prediction of circumferential through-wall cracked pipes under

very low cycle fatigue loading condition”, Engineering Fracture Mechanics , 194, 175-189 Pipe Fracture Encyclopedia, 1997 “Pipe fracture test data. Columbus (Battelle, OH, USA)” vol. 3 ABAQUS Version 6.14., 2014, “User’s Manual,” Inc Dassault Systemes Simulia , USA.