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Kim, Y. S.*; Chae, H.*; Woo, W.*; Kim, D.-K.*; Lee, D.-H.*; Harjo, S.; Kawasaki, Takuro; Lee, S. Y.*
Materials Science & Engineering A, 828, p.142059_1 - 142059_10, 2021/11
Times Cited Count：16 Percentile：79.15(Nanoscience & Nanotechnology)Zhang, X. X.*; Knoop, D.*; Andr
, H.*; Harjo, S.; Kawasaki, Takuro; Lutz, A.*; Lahres, M.*
International Journal of Plasticity, 140, p.102972_1 - 102972_20, 2021/05
Times Cited Count：28 Percentile：94.42(Engineering, Mechanical)Zhang, X. X.*; Andr, H.*; Harjo, S.; Gong, W.*; Kawasaki, Takuro; Lutz, A.*; Lahres, M.*
Materials & Design, 198, p.109339_1 - 109339_9, 2021/01
Times Cited Count：43 Percentile：94.78(Materials Science, Multidisciplinary)Chae, H.*; Huang, E.-W.*; Jain, J.*; Wang, H.*; Woo, W.*; Chen, S.-W.*; Harjo, S.; Kawasaki, Takuro; Lee, S. Y.*
Materials Science & Engineering A, 762, p.138065_1 - 138065_10, 2019/08
Times Cited Count：41 Percentile：92.06(Nanoscience & Nanotechnology)Hashimoto, Naoyuki*; Isobe, Shigehito*; Oka, Hiroshi*; Hayashi, Shigenari*; Ueda, Mikito*; Yamashita, Shinichiro; Itakura, Mitsuhiro; Tsuru, Tomohito
no journal, ,
Owing to the reduced defects, low cost, and high efficiency, the additive manufacturing (AM) technique has attracted increasingly attention and has been applied in high-entropy alloys (HEAs) in recent years. For the purpose of creating new materials which show no radiation damage or prompt recovery of radiation damage, we launched a new program in which additive-manufactured HEAs are target materials and their fundamental properties are under investigation. In this presentation, we reported the some of new test results which are conducted in the program.
Yamashita, Shinichiro; Ioka, Ikuo; Oka, Hiroshi*; Isobe, Shigehito*; Hashimoto, Naoyuki*
no journal, ,
The objective of this work is the development of new reduced activation HEAs applicable to next generation small module reactor components by using additive manufacturing (3D printing) method under the support of the 2020 MEXT Innovative Nuclear Research and Development Program. In the third presentation, we will share the highlighted results on radiation properties of the newly developed HEAs in this work.
Hashimoto, Naoyuki*; Ueda, Mikito*; Hayashi, Shigenari*; Oka, Hiroshi*; Isobe, Shigehito*; Yamashita, Shinichiro; Itakura, Mitsuhiro; Tsuru, Tomohito
no journal, ,
The objective of this work is the development of new reduced activation HEAs applicable to next generation small module reactor components by using additive manufacturing (3D printing) method under the support of the 2020 MEXT Innovative Nuclear Research and Development Program. We firstly introduce the outline of this work as a part of the series presentation.
Oka, Hiroshi*; Sato, Motoki*; Hashimoto, Naoyuki*; Isobe, Shigehito*; Yamashita, Shinichiro
no journal, ,
The objective of this work is the development of new reduced activation HEAs applicable to next generation small module reactor components by using additive manufacturing (3D printing) method under the support of the 2020 MEXT Innovative Nuclear Research and Development Program. In the second presentation, we will share the highlighted results on mechanical properties as well as microstructure of the newly developed HEAs in this work.
Yamashita, Shinichiro; Ioka, Ikuo; Abe, Yosuke; Oka, Hiroshi*; Isobe, Shigehito*; Hashimoto, Naoyuki*
no journal, ,
The objective of this work is the development of new reduced activation HEAs applicable to next generation small module reactor components by using additive manufacturing (3D printing) method under the support of the 2020 MEXT Innovative Nuclear Research and Development Program. In the third presentation, we will share the highlighted results on radiation properties of the newly developed HEAs in this work.
Yamashita, Shinichiro; Hashimoto, Naoyuki*; Oka, Hiroshi*
no journal, ,
In order to understand irradiation behavior of RA-MEA, CrFeMnNi alloy, up to the range of irradiation dose exceeding 100 dpa and demonstrate the applicability of AM to some of FCC single-phase nuclear materials, ion irradiation testing was performed. The conclusions obtained are as follows: In both microstructures of CrFeMnNi alloy prepared by conventional arc-melting or AM, a dense and fine cavity formed due to ion-irradiation over 200 dpa. However, estimated swellings (
V/V), which were calculated on the assumption that the thickness of all thin film samples is constant in this study, were 0.20% for arc-melted CrFeMnNi alloy and 0.63% for SLMed CrFeMnNi alloy, respectively. In the case of RA-MEAs, regardless of the difference in fabrication method, it was experimentally confirmed that RA-MEAs have high dimensional stability. In both microstructures of 316L after ion-irradiation over 200 dpa, void formation was confirmed. Void size distribution in SLMed 316L was quite different from that in arc-melted 316L, leading to the difference in estimated swellings between SLMed and arc-melted 316Ls; 0.52% (SLM) vs 6.61% (Arc-melting) This can be explained attributing to the difference in initial microstructure. Superior irradiation resistance in RA-MEA and Applicability of AM to nuclear structural materials were successfully confirmed.
Amarsaikhan, K.*; Kawabori, Tatsuru*; Watanabe, Masashi; Imai, Yoshiyuki; Ueta, Shohei; Yan, X.; Mizoshiri, Mizue*
no journal, ,
Femtosecond laser sintering is a promising technique for 2D/3D micro additive manufacturing. In this process, nanoparticles dispersed in binders were coated on substrates, and femtosecond laser pulses were subsequently focused and scanned to write patterns. We also applied this process to fabricating SiC microstructures using SiC nanoparticles of 
100 nm in diameter. In this study, we prepared a SiC nanoparticle ink including finer SiC nanoparticles with the diameter of ~18 nm. First, a SiC nanoparticle ink with the mixture of 100 nm and 18 nm in diameters was prepared. Then, patterning properties by femtosecond laser sintering were evaluated at various laser irradiation conditions. By comparing to the reference ink (SiC nanoparticles of 100 nm in diameter), the SiC nanoparticles with fine nanoparticles (18 nm) decreased the line width. In addition, the ablation width of in the center of the lines decreased by consisting fine particles. These results suggest that the fine nanoparticles increased the surface area in the inks, resulting that the large surface increased the consumption of the irradiated energy, and thermal conductivity of the ink decreased.
Segawa, Tomoomi; Watanabe, Masashi; Kawaguchi, Koichi; Ishii, Katsunori; Kato, Masato
no journal, ,
As an innovative nuclear fuel fabrication technology, a nuclear fuel fabrication technology using a stereolithography method has been developed. In this study, additive manufacturing experiments were performed using simulated materials by the stereolithography method and the material extrusion method, and the applicability of the technologies to the nuclear fuel fabrication process was evaluated. The experimental results showed that both the stereolithography method and the material extrusion method were capable of fabricating green pellets, and the results suggest the possibility of application to the nuclear fuel fabrication process.
Kawaguchi, Koichi; Segawa, Tomoomi; Ishii, Katsunori
no journal, ,
To evaluate the applicability of the light shaping method to the MOX fuel fabrication process, photocurable resin and CeO
slurry were irradiated with 4.7 MeV He ions, and cured layer thickness was measured. The experimental results showed that the entire slurry cures in a short time. It is evaluated to be difficult to apply the light shaping method to the MOX fuel fabrication process.
Shobu, Takahisa; Tominaga, Aki; Kisohara, Naoyuki; Maeda, Toshio*; Yamagishi, Ryuichiro*; Okihara, Shinichiro*; Tsuboi, Akihiko
no journal, ,
In this study, the internal defects and strain distribution in metal additive manufacturing and their changes by laser peening were evaluated. These studies using X-ray computed tomography and diffraction technique were carried out at BL22XU in synchrotron radiation facility SPring-8. As a result, it was confirmed that a large number of voids existed inside the additive manufacturing. However, almost no difference due to laser peening was confirmed. On the other hand, it was confirmed that the strain inside the additive manufacturing was almost
神谷 潤一郎; 和田 薫
桜井 充*; ナン ティン ティン トゥエ*; 上原 孝浩*; 馬渕 拓也*
JP, 2022-142703 
Patent licensing information
【課題】高い真空排気性能を実現することができるターボ分子ポンプを提供する。 【解決手段】ターボ分子ポンプ1には、回転の軸線AXに沿って複数段のロータ翼31Aを有するロータ30と、軸線AXに沿って複数段のロータ翼31Aの間にそれぞれ配置される複数段のステータ翼14Aと、それらのロータ30、及び複数段のステータ翼14Aを内部に収容するケーシング11と、が設けられる。そして、それらの複数段のロータ翼31A、複数段のステータ翼14A、及びケーシング11を含むそのケーシング11の内部の少なくとも一部は、その素材に含まれるガスを放出させるための真空ベーキング処理が施された材料によって形成される。
