TY - GEN
T1 - Estimation of crack-arrest toughness transition and NDT temperatures from Charpy force-displacement impact traces
AU - Sokolov, Mikhail A.
PY - 2010
Y1 - 2010
N2 - A force-displacement trace of a Charpy impact test of a reactor pressure vessel (RPV) steel in the transition range has a characteristic point, the so-called "force at the end of unstable crack propagation", F a. A two-parameter Weibull probability function is used to model the distribution of the Fa in Charpy tests performed at ORNL on different RPV steels in the unirradiated and irradiated conditions. These data have a good replication at a given test temperature, thus, the statistical analysis was applicable. It is shown that when temperature is normalized to TNDT (T-TNDT) or to T100a (T-T100a) the median Fa values of different RPV steels have a tendency to form the same shape of temperature dependence. Depending on normalization temperature, T NDT or T100a, it suggests a universal shape of the temperature dependence of Fa for different RPV steels. The best fits for these temperature dependencies are presented. These dependencies are suggested for use in estimation of NDT or T100a from randomly generated Charpy impact tests. The maximum likelihood method is used to derive equations to estimate TNDT and T100a from randomly generated Charpy impact tests.
AB - A force-displacement trace of a Charpy impact test of a reactor pressure vessel (RPV) steel in the transition range has a characteristic point, the so-called "force at the end of unstable crack propagation", F a. A two-parameter Weibull probability function is used to model the distribution of the Fa in Charpy tests performed at ORNL on different RPV steels in the unirradiated and irradiated conditions. These data have a good replication at a given test temperature, thus, the statistical analysis was applicable. It is shown that when temperature is normalized to TNDT (T-TNDT) or to T100a (T-T100a) the median Fa values of different RPV steels have a tendency to form the same shape of temperature dependence. Depending on normalization temperature, T NDT or T100a, it suggests a universal shape of the temperature dependence of Fa for different RPV steels. The best fits for these temperature dependencies are presented. These dependencies are suggested for use in estimation of NDT or T100a from randomly generated Charpy impact tests. The maximum likelihood method is used to derive equations to estimate TNDT and T100a from randomly generated Charpy impact tests.
UR - http://www.scopus.com/inward/record.url?scp=77952985189&partnerID=8YFLogxK
U2 - 10.1115/PVP2009-77894
DO - 10.1115/PVP2009-77894
M3 - Conference contribution
AN - SCOPUS:77952985189
SN - 9780791843697
T3 - American Society of Mechanical Engineers, Pressure Vessels and Piping Division (Publication) PVP
SP - 811
EP - 815
BT - Proceedings of the ASME Pressure Vessels and Piping Conference 2009 - Materials and Fabrication
T2 - 2009 ASME Pressure Vessels and Piping Conference
Y2 - 26 July 2009 through 30 July 2009
ER -