TY - JOUR
T1 - Fatigue crack growth behavior of JIS SCM440 steel near fatigue threshold in 9-MPa hydrogen gas environment
AU - Tazoe, Koki
AU - Hamada, Shigeru
AU - Noguchi, Hiroshi
N1 - Publisher Copyright:
© 2017 Hydrogen Energy Publications LLC
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2017/5/4
Y1 - 2017/5/4
N2 - In this study, stress intensity factor range (ΔK) decreasing tests were conducted and the in-situ observations were used to investigate the fatigue crack growth behavior of JIS SCM440 steel near the fatigue threshold in a 9-MPa hydrogen gas environment. The fatigue crack growth rate reflected the threshold behavior of the material, although the crack propagation knee point immediately before the threshold stress intensity factor range (ΔKth) could not be distinctly identified. The fatigue crack was also observed to exhibit uneven propagation immediately before ΔKth. In contrast, the knee points in a helium gas environment and air were very distinct. Fractographic analysis further revealed the existence of intergranular facets, which were observed immediately before ΔKth in the hydrogen gas environment. Conversely, no facet was observed immediately before ΔKth in the helium gas environment and air. The formation of the facets was considered to be one of the causes of the uneven crack propagation immediately before ΔKth in the hydrogen gas environment.
AB - In this study, stress intensity factor range (ΔK) decreasing tests were conducted and the in-situ observations were used to investigate the fatigue crack growth behavior of JIS SCM440 steel near the fatigue threshold in a 9-MPa hydrogen gas environment. The fatigue crack growth rate reflected the threshold behavior of the material, although the crack propagation knee point immediately before the threshold stress intensity factor range (ΔKth) could not be distinctly identified. The fatigue crack was also observed to exhibit uneven propagation immediately before ΔKth. In contrast, the knee points in a helium gas environment and air were very distinct. Fractographic analysis further revealed the existence of intergranular facets, which were observed immediately before ΔKth in the hydrogen gas environment. Conversely, no facet was observed immediately before ΔKth in the helium gas environment and air. The formation of the facets was considered to be one of the causes of the uneven crack propagation immediately before ΔKth in the hydrogen gas environment.
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U2 - 10.1016/j.ijhydene.2017.03.223
DO - 10.1016/j.ijhydene.2017.03.223
M3 - Article
AN - SCOPUS:85018340854
VL - 42
SP - 13158
EP - 13170
JO - International Journal of Hydrogen Energy
JF - International Journal of Hydrogen Energy
SN - 0360-3199
IS - 18
ER -
