TY - JOUR
T1 - Constant-load delayed fracture test of atmospherically corroded high strength steels
AU - Akiyama, Eiji
AU - Matsukado, Katsuhiro
AU - Li, Songjie
AU - Tsuzaki, Kaneaki
N1 - Funding Information:
Thanks are due to Mrs. Y. Hirota and R. Araki of National Institute for Materials Science for the assistance of TDS measurements and corrosion tests, respectively. This study is partially supported by the ministry of Education, Culture, Science and Technology, Grant-in-Aid for Scientific Research (C) 20560686, 2008-2010.
PY - 2011/7/15
Y1 - 2011/7/15
N2 - Constant load tests of circumferentially notched round bar specimens of high strength steels after cyclic corrosion test and outdoor exposure have been performed to demonstrate that delayed fracture occurs when the hydrogen content from the environment, H E , exceeds the critical hydrogen content for delayed fracture, H C . During the constant load tests the humidity around the specimen was increased in stepwise manner to increase hydrogen entry. After fracture the specimen was kept at the humidity long enough to homogenize hydrogen in the specimen and to obtain more quantitative hydrogen content by thermal desorption analysis. H E of the fractured specimens was higher than H C , and H E of the specimens not fractured was lower than H C . This result confirms that the balance between H C and H E determines the occurrence of delayed fracture and that hydrogen-content-based evaluation of susceptibility to delayed fracture is reasonable. To certify the increase of H E with increase in humidity, electrochemical hydrogen permeation test was carried out. The hydrogen permeation current density was increased especially at 98%RH. Enhancement of hydrogen entry with increase in CCT number was also shown by the test.
AB - Constant load tests of circumferentially notched round bar specimens of high strength steels after cyclic corrosion test and outdoor exposure have been performed to demonstrate that delayed fracture occurs when the hydrogen content from the environment, H E , exceeds the critical hydrogen content for delayed fracture, H C . During the constant load tests the humidity around the specimen was increased in stepwise manner to increase hydrogen entry. After fracture the specimen was kept at the humidity long enough to homogenize hydrogen in the specimen and to obtain more quantitative hydrogen content by thermal desorption analysis. H E of the fractured specimens was higher than H C , and H E of the specimens not fractured was lower than H C . This result confirms that the balance between H C and H E determines the occurrence of delayed fracture and that hydrogen-content-based evaluation of susceptibility to delayed fracture is reasonable. To certify the increase of H E with increase in humidity, electrochemical hydrogen permeation test was carried out. The hydrogen permeation current density was increased especially at 98%RH. Enhancement of hydrogen entry with increase in CCT number was also shown by the test.
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U2 - 10.1016/j.apsusc.2011.03.037
DO - 10.1016/j.apsusc.2011.03.037
M3 - Article
AN - SCOPUS:79958807730
SN - 0169-4332
VL - 257
SP - 8275
EP - 8281
JO - Applied Surface Science
JF - Applied Surface Science
IS - 19
ER -