TY - JOUR
T1 - Study on microstructural changes in thermally-aged stainless steel weld-overlay cladding of nuclear reactor pressure vessels by atom probe tomography
AU - Takeuchi, T.
AU - Kameda, J.
AU - Nagai, Y.
AU - Toyama, T.
AU - Nishiyama, Y.
AU - Onizawa, K.
N1 - Funding Information:
This study was carried out under the Cooperative Research Program of International Research Center for Nuclear Materials Science, Institute for Materials Research (IMR), Tohoku University. A part of this study was the result of “Study of degradation mechanism of stainless steel weld overlay cladding of nuclear reactor pressure vessels” carried out under the Strategic Promotion Program for Basic Nuclear Research by the Ministry of Education, Culture, Sports, Science and Technology of Japan. This study was partially supported by Grant-in-Aid for Scientific Research (A) (21246142) of the Ministry of Education, Culture, Sports, Science and Technology (MEXT) and by the Budget for Nuclear Research of the Ministry of Education, Culture, Sports, Science and Technology, based on the screening and counseling by the Atomic Energy Commission.
PY - 2011/8/15
Y1 - 2011/8/15
N2 - The effect of thermal aging on microstructural changes was investigated in stainless steel weld-overlay cladding composed of 90% austenite and 10% δ-ferrite phases using atom probe tomography (APT). In as-received materials subjected to cooling process after post-welding heat treatments (PWHT), a slight fluctuation of the Cr concentration was already observed due to spinodal decomposition in the ferrite phase but not in the austenitic phase. Thermal aging at 400 °C for 10,000 h caused not only an increase in the amplitude of spinodal decomposition but also the precipitation of G phases with composition ratios of Ni:Si:Mn = 16:7:6 in the ferrite phase. The chemical compositions of M23C6 type carbides seemed to be formed at the austenite/ferrite interface were analyzed. The analyses of the magnitude of the spinodal decomposition and the hardness implied that the spinodal decomposition was the main cause of the hardening.
AB - The effect of thermal aging on microstructural changes was investigated in stainless steel weld-overlay cladding composed of 90% austenite and 10% δ-ferrite phases using atom probe tomography (APT). In as-received materials subjected to cooling process after post-welding heat treatments (PWHT), a slight fluctuation of the Cr concentration was already observed due to spinodal decomposition in the ferrite phase but not in the austenitic phase. Thermal aging at 400 °C for 10,000 h caused not only an increase in the amplitude of spinodal decomposition but also the precipitation of G phases with composition ratios of Ni:Si:Mn = 16:7:6 in the ferrite phase. The chemical compositions of M23C6 type carbides seemed to be formed at the austenite/ferrite interface were analyzed. The analyses of the magnitude of the spinodal decomposition and the hardness implied that the spinodal decomposition was the main cause of the hardening.
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U2 - 10.1016/j.jnucmat.2011.06.004
DO - 10.1016/j.jnucmat.2011.06.004
M3 - Article
AN - SCOPUS:79960739280
SN - 0022-3115
VL - 415
SP - 198
EP - 204
JO - Journal of Nuclear Materials
JF - Journal of Nuclear Materials
IS - 2
ER -