TY - JOUR
T1 - Microstructural characterization of the synergic effects of dynamic strain ageing and hydrogen on fracture behaviour of low-alloy RPV steels in high-temperature water environments
AU - Que, Zaiqing
AU - Heczko, M.
AU - Kuběna, I.
AU - Seifert, H.P.
AU - Spätig, P.
N1 - Funding Information:
The funding for the “SAFE-II” and “LEAD” projects from the Swiss Federal Nuclear Safety Inspectorate (ENSI) is gratefully acknowledged. The equipment and the base of large infrastructures for research, experimental development and innovation – project IPMinfra LM2015069 and CEITEC Nano Research Infrastructure (ID LM2015041, MEYS CR, 2016–2019) were used during the research activities. Support from the Thermo Fisher Scientific & Czechoslovak Microscopy Society fellowship awarded to M. Heczko is gratefully acknowledged. The authors would like to express their gratitude for the experimental contributions and helpful suggestions from S. Ritter, G. S. Rao, H. Kottmann, B. Baumgartner and R. Schwenold from Paul Scherrer Institut.
Funding Information:
The funding for the ?SAFE-II? and ?LEAD? projects from the Swiss Federal Nuclear Safety Inspectorate (ENSI) is gratefully acknowledged. The equipment and the base of large infrastructures for research, experimental development and innovation ? project IPMinfra LM2015069 and CEITEC Nano Research Infrastructure (ID LM2015041, MEYS CR, 2016?2019) were used during the research activities. Support from the Thermo Fisher Scientific & Czechoslovak Microscopy Society fellowship awarded to M. Heczko is gratefully acknowledged. The authors would like to express their gratitude for the experimental contributions and helpful suggestions from S. Ritter, G. S. Rao, H. Kottmann, B. Baumgartner and R. Schwenold from Paul Scherrer Institut. The raw/processed data required to reproduce these findings cannot be shared at this time due to technical or time limitations.
Publisher Copyright:
© 2020 Elsevier Inc.
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2020
Y1 - 2020
N2 - Tensile tests in high-temperature air with pre-charged hydrogen and elastic plastic fracture mechanics tests in hydrogenated high-temperature water (HTW) at 250 and 288 °C on low-alloy reactor pressure vessel (RPV) steels revealed a clear but moderate reduction of ductility and fracture resistance, respectively. The observed behaviour is a consequence of synergistic effects between hydrogen embrittlement (HE) and the dynamic strain ageing (DSA), in which the HE was amplified by a high DSA susceptibility. The deformation microstructures in the vicinity of the crack tips in air and HTW of two RPV steels with high DSA susceptibility were characterized in detail. These investigations support the idea that the environmental degradation of fracture resistance in hydrogenated HTW was mainly due to the plasticity localization by the interaction between DSA and hydrogen in RPV steels. Synergistic effects of DSA and hydrogen lead to heterogeneous distribution of dislocations and formation of dislocation cells inside bainitic laths.
AB - Tensile tests in high-temperature air with pre-charged hydrogen and elastic plastic fracture mechanics tests in hydrogenated high-temperature water (HTW) at 250 and 288 °C on low-alloy reactor pressure vessel (RPV) steels revealed a clear but moderate reduction of ductility and fracture resistance, respectively. The observed behaviour is a consequence of synergistic effects between hydrogen embrittlement (HE) and the dynamic strain ageing (DSA), in which the HE was amplified by a high DSA susceptibility. The deformation microstructures in the vicinity of the crack tips in air and HTW of two RPV steels with high DSA susceptibility were characterized in detail. These investigations support the idea that the environmental degradation of fracture resistance in hydrogenated HTW was mainly due to the plasticity localization by the interaction between DSA and hydrogen in RPV steels. Synergistic effects of DSA and hydrogen lead to heterogeneous distribution of dislocations and formation of dislocation cells inside bainitic laths.
KW - Dynamic strain ageing
KW - Fracture resistance
KW - Hydrogen embrittlement
KW - Low-alloy steel
KW - Plasticity localization
KW - Scanning transmission electron microscopy
UR - http://www.scopus.com/inward/record.url?scp=85085581046&partnerID=8YFLogxK
U2 - 10.1016/j.matchar.2020.110405
DO - 10.1016/j.matchar.2020.110405
M3 - Article
SN - 1044-5803
VL - 165
JO - Materials Characterization
JF - Materials Characterization
M1 - 110405
ER -