TY - JOUR
T1 - Study on hydrogen embrittlement and dynamic strain ageing on low-alloy reactor pressure vessel steels
AU - Rao, G. S.
AU - Yagodzinskyy, Y.
AU - Que, Zaiqing
AU - Spätig, P.
AU - Seifert, H. P.
N1 - Funding Information:
The funding for the “SAFE-II” and “LEAD” projects from the Swiss Federal Nuclear Safety Inspectorate (ENSI) is gratefully acknowledged.
PY - 2021/12/1
Y1 - 2021/12/1
N2 - Tensile tests in air with hydrogen pre-charged smooth specimens and slow strain rate tests with smooth and notched specimens in hydrogenated high-temperature water (HTW) at elevated temperatures (250−288 °C) on low-alloy reactor pressure vessel (RPV) steels revealed a softening in strength and a pronounced reduction in ductility, where the magnitude of hydrogen embrittlement (HE) increased with the dynamic strain ageing (DSA) susceptibility of the RPV steels. In hydrogen pre-charged specimens and in hydrogenated HTW, shear dominated transgranular fracture by microvoid coalescence with increasing amounts of macrovoids, quasi-cleavage regions and secondary cracking were observed. Thermal desorption spectroscopy showed an increase in the concentration of trapped hydrogen in high binding energy traps (vacancies & voids) induced by straining in DSA regime. The observed hydrogen effects on fracture behaviour is a consequence of plasticity localization resulting from the interaction between DSA and hydrogen. HESIV and HELP are the dominant HE mechanisms.
AB - Tensile tests in air with hydrogen pre-charged smooth specimens and slow strain rate tests with smooth and notched specimens in hydrogenated high-temperature water (HTW) at elevated temperatures (250−288 °C) on low-alloy reactor pressure vessel (RPV) steels revealed a softening in strength and a pronounced reduction in ductility, where the magnitude of hydrogen embrittlement (HE) increased with the dynamic strain ageing (DSA) susceptibility of the RPV steels. In hydrogen pre-charged specimens and in hydrogenated HTW, shear dominated transgranular fracture by microvoid coalescence with increasing amounts of macrovoids, quasi-cleavage regions and secondary cracking were observed. Thermal desorption spectroscopy showed an increase in the concentration of trapped hydrogen in high binding energy traps (vacancies & voids) induced by straining in DSA regime. The observed hydrogen effects on fracture behaviour is a consequence of plasticity localization resulting from the interaction between DSA and hydrogen. HESIV and HELP are the dominant HE mechanisms.
KW - Dynamic strain ageing
KW - Hydrogen embrittlement
KW - Low-alloy steel
KW - Reactor pressure vessel
KW - Thermal desorption spectroscopy
UR - http://www.scopus.com/inward/record.url?scp=85109582359&partnerID=8YFLogxK
U2 - 10.1016/j.jnucmat.2021.153161
DO - 10.1016/j.jnucmat.2021.153161
M3 - Article
AN - SCOPUS:85109582359
SN - 0022-3115
VL - 556
JO - Journal of Nuclear Materials
JF - Journal of Nuclear Materials
M1 - 153161
ER -