Microstructural features and ductile-brittle transition behavior in hot-rolled lean duplex stainless steels

Takahashi, Osamu*; Shibui, Yohei*; Xu, P. G.; Harjo, S.; Suzuki, Tetsuya*; Tomota, Yo*

Quantum Beam Science (Internet), 4(1), p.16_1 - 16_15, 2020/03

https://doi.org/10.3390/qubs4010016

On the effects of fatigue precracking on the microstructure around precrack in 1TCT fracture toughness specimen of F82H-IEA

Tanigawa, Hiroyasu; Hashimoto, Naoyuki*; Sokolov, M. A.*; Klueh, R. L.*; Ando, Masami

Fusion Materials Semiannual Progress Report for the Period Ending (DOE/ER-0313/35), p.58 - 60, 2004/04

1TCT fracture toughness specimens of F82H-IEA steel were fatigue precracked and sliced in specimen thickness wise for microstructure analysis around the precrack. The microstructure around the precrack was observed by optical microscopy (OM), scanning electron microscopy (SEM), orientation imaging microscopy (OIM), and transmission electron microscopy (TEM). TEM samples around the crack front were prepared by focused ion beam (FIB) processor. The fracture surfaces of tested 1TCT specimens were also observed. OM observation showed that the precrack penetration was straight in the beginning, and then tended to follow a prior austenite grain boundary and to branch into 2 to 3 directions at the terminal. SEM and OIM observations revealed that the both microstructures around the precracks and ahead of the precrack had turned into cell structure, which is the typical microstructure of fatigue-loaded F82H. TEM images and inverse pole figures obtained from the crack-front region confirmed this structure change.

Development of a small specimen test machine to evaluate irradiation embrittlement of fusion reactor materials

Ishii, Toshimitsu; Omi, Masao; Saito, Junichi; Hoshiya, Taiji; Ooka, Norikazu; Jitsukawa, Shiro; Eto, Motokuni

Journal of Nuclear Materials, 283-287(Part.2), p.1023 - 1027, 2000/12

https://doi.org/10.1016/S0022-3115(00)00093-3

no abstracts in English

Evaluation of charpy impact property in high strength ferritic/martensitic steel (PNC-FMS)

;

JNC TN9400 2000-035, 164 Pages, 2000/03

JNC-TN9400-2000-035.pdf:3.67MB

High Strength Ferritic/Martensitic Steel (PNC-FMS : 0.12C-11Cr-0,5Mo-2W-0.2V-0.05Nb), developed by JNC, is one of the candidate materials for the long-life core of large-scale fast breeder reactor. Ductile brittle transition temperature (DBTT) was tentatively determined in 1992 in material design base standard of PNC-FMS. Howevcr, specimen size effect on impact property and upper shelf energy (USE) have not been evaluated. ln this study, effects of specimen size, thermal aging and neutron irradiation on the charpy impact property of PNC-FMS were evaluated, using together with recently obtained data. The design value of USE and DBTT as fabricated and each correlation of aging and irradiation effects were determined. The results are summarized as follows. (1)lt was found that USE is related to (Bb) as USE=m(Bb), where B is specimen width, b is ligament size and both m and n are constant. For PNC-FMS, n value is equal to 1.4. It's possible to determine n value from USE (J) for full size specimen using the correlation: n=1.3810 USE + 1.20. (2)lt was clarified that DBTT is correlated with (BKt) as DBTT=p(logBKt)+q, where Kt is elastic stress concentration factor and both p and q are constant. For PNC-FMS, the correlation is as follows: DBTT=119(logBKt)-160. (3)DBTT estimated at the irradiation temperature from 350 to 650 C for sub size specimen (width and height are 3 and 10 mm, respectively), was below 180 C, based on the design value of DBTT as fabricated and each correlation of aging and irradiation effects.

Nondestructive evaluation for characterizing neutron irradiation embrittlement of materials by using ultrasonic technique

; Ooka, Norikazu; Kobayashi, Hideo*

Proc. of 2nd Japan-US Symp. on Advances in NDT, p.151 - 156, 1999/00

no abstracts in English

Investigation on the evaluation of cleavage fracture toughness using PCCv specimens in the ductile-brittle transition range of reactor pressure vessel steels (contract research)

Onizawa, Kunio; Tobita, Toru; Suzuki, Masahide

JAERI-Research 97-081, 36 Pages, 1997/11

JAERI-Research-97-081.pdf:1.44MB

no abstracts in English

JAERI contribution for the IAEA coordinated research program; Phase III(CRP-3) on optimizing of reactor pressure vessel surveillance programmes and their analysis

Onizawa, Kunio; Suzuki, Masahide; Ueda, Shuzo

JAERI-M 93-201, 73 Pages, 1993/10

JAERI-M-93-201.pdf:1.58MB

no abstracts in English

Electrochemical evaluation of thermal aging embrittlement of 21/4Cr-1Mo steel for the pressure vessel of High Temperature Engineering Test Reactor

Nishiyama, Yutaka; Fukaya, Kiyoshi; Suzuki, Masahide; Eto, Motokuni; *

Tainetsu Kinzoku Zairyo Dai-123-Iinkai Kenkyu Hokoku, 32(2), p.169 - 175, 1991/00

no abstracts in English

Evaluation of neutron irradiation embrittlement of heavy section nuclear reactor pressure vessel steels in terms of elastic-plastic fracture toughness

; ; ; ;

Nucl.Eng.Des., 85, p.1 - 13, 1985/00

https://doi.org/10.1016/0029-5493(85)90265-1

no abstracts in English

Reactor safety research in Japan

Genshiryoku Kogyo, 21(10), p.54 - 60, 1975/10

http://ci.nii.ac.jp/naid/40001071949

no abstracts in English