TY - GEN
T1 - Fracture behavior of aged CF8A austenite cast stainless steel under dynamic and cyclic loading conditions
AU - Kim, Jin Weon
AU - Choi, Myung Rak
AU - Kim, Yun Jae
N1 - Funding Information:
This research was supported byNuclear Power Core Technology Development Program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP), granted financial resource from the Ministryof Trade, Industry& Energy, Republic of Korea (20141520100860).
Publisher Copyright:
© Copyright 2017 ASME.
PY - 2017
Y1 - 2017
N2 - This study conducted J-R fracture toughness tests using aged CF8A cast austenitic stainless steel (CASS) under dynamic and cyclic loading conditions at room temperature (RT) and 316°C and investigated the effect of seismic loading characteristics on the fracture behavior of age-related degraded material. For comparison, J-R fracture tests were also conducted on unaged CF8A CASS. CF8A CASS was made as a static casting, and it was aged thermally at 400°C for 175 days, which is equivalent to thermal aging at the operating temperature of nuclear power plants (NPPs) for 32 effective full power years (EFPYs). Monotonic J-R tests were conducted at both quasi-static and dynamic loading rates, and cyclic J-R tests were conducted at a quasi-static loading rate. The results showed that the fracture resistance of aged CF8A CASS under monotonic load was lower, by ∼35%, than that of unaged CF8A CASS, regardless of test temperatures and loading rates. The dynamic loading effect on fracture behavior was almost negligible for both unaged and aged CF8A CASSs at RT and 316°C. Cyclic loading reduced JR fracture toughness of unaged CF8A CASS considerably at both test temperatures. Such a cyclic loading effect on fracture behavior was still observed from aged CF8A CASS. Thus, we conclude that the dynamic and cyclic loading effects on fracture behavior of CF8A CASS were not altered by thermal aging at the operating temperature of NPPs for 32 EFPYs.
AB - This study conducted J-R fracture toughness tests using aged CF8A cast austenitic stainless steel (CASS) under dynamic and cyclic loading conditions at room temperature (RT) and 316°C and investigated the effect of seismic loading characteristics on the fracture behavior of age-related degraded material. For comparison, J-R fracture tests were also conducted on unaged CF8A CASS. CF8A CASS was made as a static casting, and it was aged thermally at 400°C for 175 days, which is equivalent to thermal aging at the operating temperature of nuclear power plants (NPPs) for 32 effective full power years (EFPYs). Monotonic J-R tests were conducted at both quasi-static and dynamic loading rates, and cyclic J-R tests were conducted at a quasi-static loading rate. The results showed that the fracture resistance of aged CF8A CASS under monotonic load was lower, by ∼35%, than that of unaged CF8A CASS, regardless of test temperatures and loading rates. The dynamic loading effect on fracture behavior was almost negligible for both unaged and aged CF8A CASSs at RT and 316°C. Cyclic loading reduced JR fracture toughness of unaged CF8A CASS considerably at both test temperatures. Such a cyclic loading effect on fracture behavior was still observed from aged CF8A CASS. Thus, we conclude that the dynamic and cyclic loading effects on fracture behavior of CF8A CASS were not altered by thermal aging at the operating temperature of NPPs for 32 EFPYs.
UR - http://www.scopus.com/inward/record.url?scp=85034097296&partnerID=8YFLogxK
U2 - 10.1115/PVP2017-65676
DO - 10.1115/PVP2017-65676
M3 - Conference contribution
AN - SCOPUS:85034097296
T3 - American Society of Mechanical Engineers, Pressure Vessels and Piping Division (Publication) PVP
BT - Design and Analysis
PB - American Society of Mechanical Engineers (ASME)
T2 - ASME 2017 Pressure Vessels and Piping Conference, PVP 2017
Y2 - 16 July 2017 through 20 July 2017
ER -