TY - JOUR
T1 - Effect of microstructural change on creep rupture during creep deformation in 18Cr-9Ni-3Cu-Nb-N steel
AU - Mitsuhara, Masatoshi
AU - Ikeda, Ken Ichi
AU - Nakashima, Hideharu
AU - Hayakawa, Hiroyuki
AU - Kusumoto, Jun Ichi
AU - Kanaya, Akihiro
N1 - Copyright:
Copyright 2010 Elsevier B.V., All rights reserved.
PY - 2008
Y1 - 2008
N2 - 18Cr-9Ni-3Cu-Nb-N steel has the highest creep strength in the austenitic heat-resistant steels. It is expected as the component of the future thermal power plants. In order to clarify the mechanism of creep strengthening and creep rupture for the 18Cr-9Ni-3Cu-Nb-N steel, the creep test and the microstructural observations using electron microscopy were carried out. Seamless pipe was used as the sample because the initial microstructure for the sample conformed to the one for steels in the plants. From the TEM observation, fine NbX and Cu particles were formed in the austenite grains. The pinning effect by these particles is effective for the creep strengthening. In the regard to the microstructural change during the creep deformation, the crystal orientation rotations were observed using SEM-OIM. In the crystal grains rotated during the creep deformation, (001) or (111) was oriented to the tensile direction. Many boundaries were cracked due to these crystal rotations. This means that the creep rupture is occurred by the difference of the plastic deformation behavior between the grains oriented (001) to the tensile direction and the grains oriented (111) to it.
AB - 18Cr-9Ni-3Cu-Nb-N steel has the highest creep strength in the austenitic heat-resistant steels. It is expected as the component of the future thermal power plants. In order to clarify the mechanism of creep strengthening and creep rupture for the 18Cr-9Ni-3Cu-Nb-N steel, the creep test and the microstructural observations using electron microscopy were carried out. Seamless pipe was used as the sample because the initial microstructure for the sample conformed to the one for steels in the plants. From the TEM observation, fine NbX and Cu particles were formed in the austenite grains. The pinning effect by these particles is effective for the creep strengthening. In the regard to the microstructural change during the creep deformation, the crystal orientation rotations were observed using SEM-OIM. In the crystal grains rotated during the creep deformation, (001) or (111) was oriented to the tensile direction. Many boundaries were cracked due to these crystal rotations. This means that the creep rupture is occurred by the difference of the plastic deformation behavior between the grains oriented (001) to the tensile direction and the grains oriented (111) to it.
UR - http://www.scopus.com/inward/record.url?scp=77952396804&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77952396804&partnerID=8YFLogxK
U2 - 10.2355/tetsutohagane.94.299
DO - 10.2355/tetsutohagane.94.299
M3 - Article
AN - SCOPUS:77952396804
VL - 94
SP - 299
EP - 304
JO - Tetsu-To-Hagane/Journal of the Iron and Steel Institute of Japan
JF - Tetsu-To-Hagane/Journal of the Iron and Steel Institute of Japan
SN - 0021-1575
IS - 8
ER -