TY - JOUR
T1 - Hydrogen diffusion in ultrafine-grained iron with the body-centered cubic crystal structure
AU - Iwaoka, Hideaki
AU - Arita, Makoto
AU - Horita, Zenji
N1 - Funding Information:
This work was supported in part by Grant-in-Aids from the MEXT, Japan [grant number 16K18268], [grant number 26220909], [grant number 15K14183]. One of the authors (HI) would like to thank a Grant-in-aid for encouragement of young scientists in the Faculty of Engineering, Kyushu University. The HPT process was carried out in the International Research Center on Giant Straining for Advanced Materials (IRC-GSAM) at Kyushu University.
Publisher Copyright:
© 2017 Informa UK Limited, trading as Taylor & Francis Group.
PY - 2017/4/3
Y1 - 2017/4/3
N2 - The role of grain boundaries in Fe on hydrogen diffusion has been investigated by electrochemical permeation tests using ultrafine-grained Fe produced by high-pressure torsion (HPT) processing. Permeation tests were also conducted on cold-rolled and water-quenched Fe to understand the trapping effect of dislocations and vacancies. Hydrogen diffusion was delayed in all these discs. However, the delay mechanism in the HPT-processed disc was different from that in rolled and water-quenched Fe. Grain boundaries do not act as trapping sites but slow the diffusion. The diffusion coefficients of hydrogen were significantly decreased by HPT processing on account of the high activation energy for hydrogen diffusion in grain boundaries.
AB - The role of grain boundaries in Fe on hydrogen diffusion has been investigated by electrochemical permeation tests using ultrafine-grained Fe produced by high-pressure torsion (HPT) processing. Permeation tests were also conducted on cold-rolled and water-quenched Fe to understand the trapping effect of dislocations and vacancies. Hydrogen diffusion was delayed in all these discs. However, the delay mechanism in the HPT-processed disc was different from that in rolled and water-quenched Fe. Grain boundaries do not act as trapping sites but slow the diffusion. The diffusion coefficients of hydrogen were significantly decreased by HPT processing on account of the high activation energy for hydrogen diffusion in grain boundaries.
UR - http://www.scopus.com/inward/record.url?scp=85015211675&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85015211675&partnerID=8YFLogxK
U2 - 10.1080/09500839.2017.1300702
DO - 10.1080/09500839.2017.1300702
M3 - Article
AN - SCOPUS:85015211675
SN - 0950-0839
VL - 97
SP - 158
EP - 168
JO - Philosophical Magazine Letters
JF - Philosophical Magazine Letters
IS - 4
ER -