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Ikushima, Kazuki*; Shibahara, Masakazu*; Nishikawa, Satoru*; Furukawa, Takashi*; Akita, Koichi; Suzuki, Hiroshi; Morooka, Satoshi
E-Journal of Advanced Maintenance (Internet), 9(3), p.NT87_1 - NT87_5, 2017/11
Akita, Koichi; Shibahara, Masakazu*; Ikushima, Kazuki*; Nishikawa, Satoru*; Furukawa, Takashi*; Suzuki, Hiroshi; Harjo, S.; Kawasaki, Takuro; Vladimir, L.*
Yosetsu Gakkai Rombunshu (Internet), 35(2), p.112s - 116s, 2017/06
Ikushima, Kazuki*; Kitani, Yuji*; Shibahara, Masakazu*; Nishikawa, Satoru*; Furukawa, Takashi*; Akita, Koichi; Suzuki, Hiroshi; Morooka, Satoshi
Yosetsu Gakkai Rombunshu (Internet), 35(2), p.75s - 79s, 2017/06
Ikushima, Kazuki*; Shibahara, Masakazu*; Akita, Koichi; Suzuki, Hiroshi; Morooka, Satoshi; Nishikawa, Satoru*; Furukawa, Takashi*
Welding in the World, 61(3), p.517 - 527, 2017/05
In this study, first, an analysis method to predict the behaviour of residual stress distribution on shot peening process was proposed. In the proposed method, the load distribution on the collision of shots was modelled, and it was integrated with the dynamic analysis method based on the idealized explicit FEM (IEFEM). The accuracy of the proposed analysis system was confirmed by comparing the stress distribution on the collision of a single shot with the results analyzed by ABAQUS. The thermal elastic plastic analysis method using IEFEM was applied to the analysis of residual stress distribution of multi-pass welded pipe joint. The calculated residual stress distribution was compared with the measured residual stress distribution using X-ray diffraction (XRD). As a result, it was shown that the both welding residual distribution agree well with each other. Considering the calculated welding residual stress distribution, the modification of stress distribution due to shot peening was predicted by the proposed analysis system. As a result, the similar stress distribution with measurement by XRD was obtained in case that a large number of collisions are considered.
Suzuki, Kenji*; Yamagishi, Aoi*; Nishikawa, Satoru*; Shobu, Takahisa
Hozengaku, 11(2), p.91 - 98, 2012/07
In this study, a residual stress distribution in a dissimilar plate butt-welded joint was simulated by a thermo-elastic finite element method. The base metal was the austenitic stainless steel SUS316L. The other base metal was nickel super-alloy NCF600, and the weld metal was the alloy 82 (YNiCr-3). The dimensions of the plate butt-welded joint were a width of 200 mm, a length of 250 mm and a thickness of 25 mm. The welding joint was fabricated by TIG welding with 22 passes. For comparison, the residual stress distribution for the similar butt-welded joint of SUS316L was simulated as well as the dissimilar welded joint. According to the simulated results, there was not the difference in the thermal field between the similar and the dissimilar welded joints. The residual stress distribution in the similar welded joint became symmetrical to the welding center after removal of the weld bead. For the dissimilar welded joint, the peak of the residual stresses moved to the NCF600 side a little. The residual stress level of the dissimilar welded joint was large compared with the similar welded joint. The residual stress of the welding direction was larger than that of the transverse direction.
Akita, Koichi; Suzuki, Hiroshi; Nishikawa, Satoru*; Okita, Shigeru*
Nihon Zairyo Gakkai Dai-61-Ki Tsujo Sokai, Gakujutsu Koenkai Rombunshu (USB Flash Drive), 2 Pages, 2012/05
Residual stresses on the surface and inside of ultrasonic shot peened dissimilar weld joint were measured using X-ray and neutron diffraction before and after thermal loading. Mechanism of residual stress relaxation due to thermal loading was discussed.
thin film detector for neutronsIshida, Takekazu*; Nishikawa, Masatoshi*; Fujita, Yoshifumi*; Okayasu, Satoru; Katagiri, Masaki*; Sato, Kazuo*; Yotsuya, Tsutomu*; Shimakage, Hisashi*; Miki, Shigehito*; Wang, Z.*; et al.
Journal of Low Temperature Physics, 151(3-4), p.1074 - 1079, 2008/05
Times Cited Count：36 Percentile：78.05(Physics, Applied)The superconducting neutron detector using high-quality 
B-enriched MgB thin films at higher operating temperatures has been proposed, where a resistance change induced by the nuclear reaction of neutron and B in MgB is used to detect a neutron. Cold neutrons from a nuclear research reactor irradiated the MgB detector, and the output voltage was clearly observed through a low-noise amplifier by using a digital oscilloscope. The out-of-equilibrium thermodynamics was investigated by means of the time-dependent Ginzburg-Landau equations by using the Earth Simulator.
Yamasaki, Chisato*; Murakami, Katsuhiko*; Fujii, Yasuyuki*; Sato, Yoshiharu*; Harada, Erimi*; Takeda, Junichi*; Taniya, Takayuki*; Sakate, Ryuichi*; Kikugawa, Shingo*; Shimada, Makoto*; et al.
Nucleic Acids Research, 36(Database), p.D793 - D799, 2008/01
Times Cited Count：51 Percentile：71.25(Biochemistry & Molecular Biology)Here we report the new features and improvements in our latest release of the H-Invitational Database, a comprehensive annotation resource for human genes and transcripts. H-InvDB, originally developed as an integrated database of the human transcriptome based on extensive annotation of large sets of fulllength cDNA (FLcDNA) clones, now provides annotation for 120 558 human mRNAs extracted from the International Nucleotide Sequence Databases (INSD), in addition to 54 978 human FLcDNAs, in the latest release H-InvDB. We mapped those human transcripts onto the human genome sequences (NCBI build 36.1) and determined 34 699 human gene clusters, which could define 34 057 protein-coding and 642 non-protein-coding loci; 858 transcribed loci overlapped with predicted pseudogenes.
Ushigusa, Kenkichi; Seki, Masahiro; Ninomiya, Hiromasa; Norimatsu, Takayoshi*; Kamada, Yutaka; Mori, Masahiro; Okuno, Kiyoshi; Shibanuma, Kiyoshi; Inoue, Takashi; Sakamoto, Keishi; et al.
Genshiryoku Handobukku, p.906 - 1029, 2007/11
no abstracts in English
Isobe, Kanetsugu; Nakamura, Hirofumi; Kaminaga, Atsushi; Higashijima, Satoru; Nishi, Masataka; Konishi, Satoshi*; Nishikawa, Masabumi*; Tanabe, Tetsuo*
Fusion Science and Technology, 48(1), p.302 - 305, 2005/07
Times Cited Count：5 Percentile：35.8(Nuclear Science & Technology)no abstracts in English
Horikawa, Toyohiko*; Kaminaga, Atsushi; Nakamura, Hirofumi; Higashijima, Satoru; Arai, Takashi; Kubo, Hirotaka; Konishi, Satoshi*; Nishikawa, Masabumi*
JAERI-Tech 2003-082, 66 Pages, 2003/12
JAERI-Tech-2003-082.pdf:3.44MB
no abstracts in English
Akita, Koichi; Suzuki, Hiroshi; Moriai, Atsushi; Harjo, S.; Nishikawa, Satoru*
no journal, ,
To clarify the relaxation process on dissimilar metal weld joints, 
stress measurements during thermal cycles from RT to 593 K were conducted using a neutron engineering diffractometer, TAKUMI in J-PARC. The effects of the difference in thermal expansion coefficient of the materials and the temperature dependence of the yield strength on the residual stress relaxation were discussed based on the experimental results.
Akita, Koichi; Suzuki, Hiroshi; Nishikawa, Satoru*; Moriai, Atsushi; Harjo, S.; Vladimir, L.*
no journal, ,
The materials used for the dissimilar weld joint were a SUS316L stainless steel and a NCF600 nickel alloy for the base plates, and an Alloy82 nickel alloy for the weld metal. The ultrasonic shot peening (USP) was applied to the sample surface after welding. The residual stress mappings of the as-peened and heat treated (593 K, 2 h) samples were measured at room temperature using KOWARI in ANSTO. In the results, the reduction of the tensile residual stress was observed near the interface of the weld metal and the nickel base plate. To clarify the relaxation process, the in-situ stress measurements during thermal cycles from RT to 593 K were conducted using TAKUMI in J-PARC. The effects of the difference in thermal expansion coefficient of the materials and the temperature dependence of the yield strength on the residual stress relaxation were disscussed based on the experimental results.
Akita, Koichi; Nishikawa, Satoru*; Suzuki, Hiroshi; Moriai, Atsushi; Harjo, S.
no journal, ,
Residual stress measurements inside a dissimilar metal welded joint were performed during thermal cycles using an engineering neutron diffractometer, TAKUMI in J-PARC/MLF. The materials used for the welded joint were SUS316L and NCF600 for base plates, and Alloy82 for the weld metal. Tensile residual stresses were observed at the depth of 4.2 mm of the welded joint at the room temperature. As the temperature increased, the tensile residual stresses in NCF600 and Alloy82 increased, whereas the tensile residual stress in SUS316L decreased. These phenomena in the temperature increasing process can be explained by the thermal expansion coefficient of each material.
Akita, Koichi; Nishikawa, Satoru*; Shibahara, Masakazu*; Ikushima, Kazuki*; Suzuki, Hiroshi; Moriai, Atsushi; Harjo, S.; Aizawa, Kazuya
no journal, ,
To clarify the residual stress relaxation process in a dissimilar weld joint, the in-situ neutron stress measurements during thermal cycles were conducted using TAKUMI in J-PARC. The materials used for the base plates were a Ni-alloy (NCF600) and a stainless steel (SUS316L). The temperature range was from RT to 593 K. From the experimental results, it was found that residual stress of the Ni-alloy increased, while the residual stress of the stainless steel decreased, in the heating process. And, the residual stress of the Ni-alloy reaches the yield strength of the material in the heating process. It results in the redistribution of the residual stress, and therefore the residual stress relaxation occurs.
Akita, Koichi; Moriai, Atsushi; Suzuki, Hiroshi; Harjo, S.; Nishikawa, Satoru*; Shibahara, Masakazu*; Ikushima, Kazuki*
no journal, ,
Internal residual stresses of a dissimilar weld joint under cyclic thermal aging were measured using neutron diffraction technique and the residual stress relaxation process was investigated.
Kitamura, Yoshisato*; Okada, Takashi*; Ikushima, Kazuki*; Shibahara, Masakazu*; Nishikawa, Satoru*; Akita, Koichi
no journal, ,
no abstracts in English
Ikushima, Kazuki*; Kitamura, Yoshisato*; Kitani, Yuji*; Shibahara, Masakazu*; Nishikawa, Satoru*; Akita, Koichi
no journal, ,
no abstracts in English
Ikushima, Kazuki*; Kitani, Yuji*; Kitamura, Yoshisato*; Shibahara, Masakazu*; Nishikawa, Satoru*; Furukawa, Takashi*; Akita, Koichi
no journal, ,
no abstracts in English
Shibahara, Masakazu*; Kitani, Yuji*; Ikushima, Kazuki*; Nishikawa, Satoru*; Furukawa, Takashi*; Akita, Koichi; Morooka, Satoshi; Suzuki, Hiroshi
no journal, ,
no abstracts in English
