Development of technologies for enhanced analysis accuracy of fuel debris; Summary results of the 2020 fiscal year (Subsidy program for the project of decommissioning and contaminated water management)

Ikeuchi, Hirotomo; Koyama, Shinichi; Osaka, Masahiko; Takano, Masahide; Nakamura, Satoshi; Onozawa, Atsushi; Sasaki, Shinji; Onishi, Takashi; Maeda, Koji; Kirishima, Akira*; et al.

JAEA-Technology 2022-021, 224 Pages, 2022/10

JAEA-Technology-2022-021.pdf:12.32MB

A set of technology, including acid dissolving, has to be established for the analysis of content of elements/nuclides in the fuel debris samples. In this project, a blind test was performed for the purpose of clarifying the current level of analytical accuracy and establishing the alternative methods in case that the insoluble residue remains. Overall composition of the simulated fuel debris (homogenized powder having a specific composition) were quantitatively determined in the four analytical institutions in Japan by using their own dissolving and analytical techniques. The merit and drawback for each technique were then evaluated, based on which a tentative flow of the analyses of fuel debris was constructed.

Summary results of subsidy program for the "Project of Decommissioning and Contaminated Water Management (Development of Analysis and Estimation Technology for Characterization of Fuel Debris (Development of Technologies for Enhanced Analysis Accuracy and Thermal Behavior Estimation of Fuel Debris))"

Koyama, Shinichi; Nakagiri, Toshio; Osaka, Masahiko; Yoshida, Hiroyuki; Kurata, Masaki; Ikeuchi, Hirotomo; Maeda, Koji; Sasaki, Shinji; Onishi, Takashi; Takano, Masahide; et al.

Hairo, Osensui Taisaku jigyo jimukyoku Homu Peji (Internet), 144 Pages, 2021/08

https://dccc-program.jp/3797

JAEA performed the subsidy program for the "Project of Decommissioning and Contaminated Water Management (Development of Analysis and Estimation Technology for Characterization of Fuel Debris (Development of Technologies for Enhanced Analysis Accuracy and Thermal Behavior Estimation of Fuel Debris))" in 2020JFY. This presentation summarized briefly the results of the project, which will be available shortly on the website of Management Office for the Project of Decommissioning and Contaminated Water Management.

In middle Heisei period

Nozawa, Takashi

Senmon Toshokan, (295), p.18 - 19, 2019/05

no abstracts in English

Technical basis of accident tolerant fuel updated under a Japanese R&D project

Yamashita, Shinichiro; Nagase, Fumihisa; Kurata, Masaki; Nozawa, Takashi; Watanabe, Seiichi*; Kirimura, Kazuki*; Kakiuchi, Kazuo*; Kondo, Takao*; Sakamoto, Kan*; Kusagaya, Kazuyuki*; et al.

Proceedings of 2017 Water Reactor Fuel Performance Meeting (WRFPM 2017) (USB Flash Drive), 10 Pages, 2017/09

In Japan, the research and development (R&D) project on accident tolerant fuel and other components (ATFs) of light water reactors (LWRs) has been initiated in 2015 for establishing technical basis of ATFs. The Japan Atomic Energy Agency (JAEA) has coordinated and carried out this ATF R&D project in cooperation with power plant providers, fuel venders and universities for making the best use of the experiences, knowledges in commercial uses of zirconium-base alloys (Zircaloy) in LWRs. ATF candidate materials under consideration in the project are FeCrAl steel strengthened by dispersion of fine oxide particles(FeCrAl-ODS) and silicon carbide (SiC) composite, and are expecting to endure severe accident conditions in the reactor core for a longer period of time than the Zircaloy while maintaining or improving fuel performance during normal operations. In this paper, the progresses of the R&D project are reported.

The Recent improvements on circulation of research results at the Japan Atomic Energy Agency

Inagaki, Satomi; Hayakawa, Misa; Ebisawa, Naomi; Gonda, Mayuki; Nozawa, Takashi; Itabashi, Keizo

The Grey Journal; An International Journal on Grey Literature, 13(2), p.123 - 129, 2017/00

Sharing information of scientific research results on the Internet have developed in the global advancement of the open science today, such as archiving and disseminating scientific papers on institutional repositories, facilitating access to and use of research data etc. Accessibility to those contents in large volumes of information on the Internet is very important issue. Those contents might be grey literature without solving this accessibility issue. This presentation introduces the case study of the Japan Atomic Energy Agency (JAEA) Library as an example of efforts to improve circulation of research results in terms of grey literature. JAEA has disseminate information of our research results through the JAEA Originated Papers Searching System (JOPSS) on the Internet over decade, but we have three main issues to solve aiming at improving the accessibility of grey literature in the open science era; (1) to ensure accessibility of our Internet contents, (2) to consider how our target users find our contents, (3) to improve user interface of contents. We continue to disseminate research results by paying attention to the global trend of open science.

Improving the metadata of bibliographic information to enhance its access

Hayakawa, Misa; Nagaya, Shun; Ebisawa, Naomi; Inagaki, Satomi; Nozawa, Takashi; Itabashi, Keizo

Proceedings of 4th International Conference of Asian Special Libraries (ICoASL 2015) (USB Flash Drive), 8 Pages, 2015/04

Recently, a large quantity of digital contents is distributed on the Internet. Therefore, it is important for us to consider how we can add the value and increase the access to our library bibliographic information metadata. Availability from multiple channels and providing link to the full text may become a solution. This paper describes the case of Japan Atomic Energy Agency Library, as an example to improve our library database that is providing the R&D information (academic papers, oral presentation, and technical reports) of our institute. JAEA library provides this information through JAEA Originated Papers Searching System (JOPSS). This system was improved by providing access channels for the metadata and link to full text. In addition, user interface was constructed based on the information seeking behavior.

Evaluation methods of the failure behavior of SiC/SiC composites with a scope of their application under severe environments

Nozawa, Takashi

Seramikkusu, 49(12), p.1034 - 1039, 2014/12

https://member.ceramic.or.jp/journal/vol_no/49/12/49_12.html

http://ci.nii.ac.jp/naid/40020508050

The small specimen test technique is a viable method for nuclear reactor materials irradiation because of reducing irradiation volume, radioactivity, and waste. It is important to develop the evaluation method to consider unique failure behavior of composites since composites generally show anisotropy due to discontinuity among various constituents with finite size. This paper reviewed recent progress of failure evaluation by various modes and summarized requirements and issues about the small specimen test techniques for composites. Finally, we discussed future perspectives of the small specimen test techniques toward standardization.

Stress envelope of silicon carbide composites at elevated temperatures

Nozawa, Takashi; Kim, S.*; Ozawa, Kazumi; Tanigawa, Hiroyasu

Fusion Engineering and Design, 89(7-8), p.1723 - 1727, 2014/10

https://doi.org/10.1016/j.fusengdes.2013.12.032

A SiC/SiC composite is a promising candidate material for the advanced fusion DEMO blanket. For the design of the DEMO, the stability of high-temperature strength of SiC/SiC composites needs to be identified. Additionally, strength anisotropy needs to be clarified because of its unique fabric architecture. This study therefore aims to evaluate mechanical properties by various modes at elevated temperatures, eventually providing a stress envelope for the design. A P/W Tyranno-SA3 fiber reinforced CVI SiC matrix composite with multilayered SiC/PyC interface was evaluated in this study. Tensile and compressive tests were conducted by the SSTT specifically arranged for the high-temperature use. In-plane shear properties were contrarily estimated by the off-axial tensile method assuming that the mixed mode failure criterion is valid for composites. All tests were performed in vacuum. The preliminary test results indicate no degradation of both proportional limit stress (PLS) and the ultimate tensile strength at temperatures below 1000C. Similarly, no significant degradation of high-temperature compressive and in-plane shear properties were identified, finally providing the stress envelope at elevated temperatures for the design.

4th Platform Meeting on DEMO Design

Sakamoto, Yoshiteru; Uto, Hiroyasu; Nozawa, Takashi

Purazuma, Kaku Yugo Gakkai-Shi, 90(5), P. 314, 2014/05

http://www.jspf.or.jp/Journal/PDF_JSPF/jspf2014_05/jspf2014_05-314.pdf

The 4th platform meeting was held with 35 participants from universities, industries and JAEA. The objective of the meeting is to discuss the technologies required for DEMO design by young scientists at the Rokkasho BA site. The participants have deeply discussed about design issues on fusion safety, standards, maintenance and requirements for electrical connection along the meeting theme of "Road to fusion electricity". The meeting was very meaningful and should be continued in the future.

Radiation-induced effects in physical properties of materials, 2-6; Evaluation of irradiation creep for F82H steel by using pressurized tubes

Ando, Masami; Nozawa, Takashi; Hirose, Takanori; Tanigawa, Hiroyasu

Purazuma, Kaku Yugo Gakkai-Shi, 90(1), p.64 - 67, 2014/01

http://ci.nii.ac.jp/naid/110009688791

Reduced activation ferritic/martensitic steel (RAFM) is a candidate for the material of DEMO blanket structure. The irradiation creep behavior of F82H and JLF-1 steel has been measured at 300, 400 and 500C up to 5 dpa using helium-pressurized creep tubes irradiated in HFIR. These tubes were pressurized with helium to hoop stress levels of 0400 MPa at the irradiation temperature. The results for F82H and JLF-1 with a 400 MPa hoop stress detected small creep strains ( 0.25%) after irradiation at 300C. Irradiation creep rate (creep strain/dose) was tendency to be a similar behavior for high-dose irradiated RAFM specimens in FFTF. In this paper, a procedure of irradiation creep test & evaluation was also summarized.