TY - JOUR
T1 - Hydrogen embrittlement of nodular cast iron
AU - Sahiluoma, Patrik
AU - Yagodzinskyy, Yuriy
AU - Forsström, Antti
AU - Hänninen, Hannu
AU - Bossuyt, Sven
PY - 2021/1
Y1 - 2021/1
N2 - Ferritic nodular cast iron, intended for use as the material for inserts of canisters for long-term geological disposal of spent nuclear fuel, was studied for hydrogen sensitivity. In the canisters, the insert provides the mechanical strength against external loads. Hydrogen was charged from 0.1 N H(2)SO(4)solution in free-corrosion tests and under controlled cathodic potential. Hydrogen uptake and trapping were then measured using thermal desorption spectroscopy. The hydrogen desorption rate after hydrogen charging manifests two distinct peaks. Plastic deformation during hydrogen charging increases the hydrogen uptake considerably. Hydrogen reduces the elongation to fracture and time to fracture in slow strain rate testing and constant load testing (CLT), respectively. Especially, the strain rate in CLT is dramatically increased. The appearance of hydrogen-induced cracking in the ferrite phase changes from ductile dimple fracture to brittle cleavage fracture due to hydrogen charging, which initiates from the interphases of the graphite nodules. The results are discussed in terms of the role of hydrogen and the graphite nodules in hydrogen embrittlement of ductile cast iron.
AB - Ferritic nodular cast iron, intended for use as the material for inserts of canisters for long-term geological disposal of spent nuclear fuel, was studied for hydrogen sensitivity. In the canisters, the insert provides the mechanical strength against external loads. Hydrogen was charged from 0.1 N H(2)SO(4)solution in free-corrosion tests and under controlled cathodic potential. Hydrogen uptake and trapping were then measured using thermal desorption spectroscopy. The hydrogen desorption rate after hydrogen charging manifests two distinct peaks. Plastic deformation during hydrogen charging increases the hydrogen uptake considerably. Hydrogen reduces the elongation to fracture and time to fracture in slow strain rate testing and constant load testing (CLT), respectively. Especially, the strain rate in CLT is dramatically increased. The appearance of hydrogen-induced cracking in the ferrite phase changes from ductile dimple fracture to brittle cleavage fracture due to hydrogen charging, which initiates from the interphases of the graphite nodules. The results are discussed in terms of the role of hydrogen and the graphite nodules in hydrogen embrittlement of ductile cast iron.
KW - copper canister
KW - ductile cast iron
KW - hydrogen embrittlement
KW - hydrogen thermal desorption
KW - hydrogen trapping
KW - spent nuclear fuel
KW - GRAPHITE
UR - http://www.scopus.com/inward/record.url?scp=85088315690&partnerID=8YFLogxK
U2 - 10.1002/maco.202011682
DO - 10.1002/maco.202011682
M3 - Article
VL - 72
SP - 245
EP - 254
JO - MATERIALS AND CORROSION-WERKSTOFFE UND KORROSION
JF - MATERIALS AND CORROSION-WERKSTOFFE UND KORROSION
SN - 0947-5117
IS - 1-2
ER -