Development of genetic and electrochemical diagnosis and inhibition technologies for invisible corrosion caused by microorganisms (Contract research); FY2022 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; National Institute for Materials Science*

JAEA-Review 2023-031, 101 Pages, 2024/01

JAEA-Review-2023-031.pdf:24.47MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2022. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station (1F), Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2020, this report summarizes the research results of the "Development of genetic and electrochemical diagnosis and inhibition technologies for invisible corrosion caused by microorganisms" conducted from FY2020 to FY2022. The present study aims to develop innovative diagnostic techniques such as accelerated test specimens and on-site genetic testing for microbially induced and accelerated corrosion of metallic materials (microbially influenced corrosion, MIC), and to identify the conditions that promote MIC at 1F for proposing methods to prevent MIC through water quality and environmental control.

The Precipitation and redistribution of alloying element in Zircaloy-4 cladding tube oxidized in high-temperature steam

Amaya, Masaki

High Temperature Corrosion of Materials, 15 Pages, 2024/00

https://doi.org/10.1007/s11085-023-10216-9

observation of deformation behavior in high entropy alloys using neutron diffraction

Harjo, S.

Nihon Kessho Gakkai-Shi, 65(3), p.178 - 182, 2023/08

https://doi.org/10.5940/jcrsj.65.178

Phase analysis of simulated nuclear fuel debris synthesized using UO, Zr, and stainless steel and leaching behavior of the fission products and matrix elements

Tonna, Ryutaro*; Sasaki, Takayuki*; Kodama, Yuji*; Kobayashi, Taishi*; Akiyama, Daisuke*; Kirishima, Akira*; Sato, Nobuaki*; Kumagai, Yuta; Kusaka, Ryoji; Watanabe, Masayuki

Nuclear Engineering and Technology, 55(4), p.1300 - 1309, 2023/04

https://doi.org/10.1016/j.net.2022.12.017

Simulated debris was synthesized using UO, Zr, and stainless steel and a heat treatment method under inert or oxidizing conditions. The primary U solid phase of the debris synthesized at 1473 K under inert conditions was UO, whereas a (U,Zr)O solid solution formed at 1873 K. Under oxidizing conditions, a mixture of UO and (Fe,Cr)UO phases formed at 1473 K whereas a (U,Zr)O solid solution formed at 1873 K. The leaching behavior of the fission products from the simulated debris was evaluated using two methods: the irradiation method, for which fission products were produced via neutron irradiation, and the doping method, for which trace amounts of non-radioactive elements were doped into the debris. The dissolution behavior of U depended on the properties of the debris and aqueous medium the debris was immersed in. Cs, Sr, and Ba leached out regardless of the primary solid phases. The leaching of high-valence Eu and Ru ions was suppressed, possibly owing to their solid-solution reaction with or incorporation into the uranium compounds of the simulated debris.

Tensile overload-induced texture effects on the fatigue resistance of a CoCrFeMnNi high-entropy alloy

Lam, T.-N.*; Chin, H.-H.*; Zhang, X.*; Feng, R.*; Wang, H.*; Chiang, C.-Y.*; Lee, S. Y.*; Kawasaki, Takuro; Harjo, S.; Liaw, P. K.*; et al.

Acta Materialia, 245, p.118585_1 - 118585_9, 2023/02

https://doi.org/10.1016/j.actamat.2022.118585

Development of genetic and electrochemical diagnosis and inhibition technologies for invisible corrosion caused by microorganisms (Contract Research); FY2021 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; National Institute for Materials Science*

JAEA-Review 2022-045, 82 Pages, 2023/01

JAEA-Review-2022-045.pdf:4.6MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2021. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station (1F), Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2020, this report summarizes the research results of the "Development of genetic and electrochemical diagnosis and inhibition technologies for invisible corrosion caused by microorganisms" conducted in FY2021. The present study aims to develop innovative diagnostic techniques such as accelerated test specimens and on-site genetic testing for microbially induced and accelerated corrosion of metallic materials (microbially influenced corrosion, MIC), and to identify the conditions that promote MIC at 1F for proposing methods to prevent MIC through water quality and environmental control. We also aim to develop a research base based on materials, microorganisms, and electrochemistry, to develop technologies that can be used by engineers in the field, …

Engineering formulation of the irradiation growth behavior of zirconium-based alloys for light water reactors

Kakiuchi, Kazuo; Amaya, Masaki; Udagawa, Yutaka

Journal of Nuclear Materials, 573, p.154110_1 - 154110_7, 2023/01

https://doi.org/10.1016/j.jnucmat.2022.154110

Basic research on the stability of fuel debris including alloy phase (Contract research); FY2020 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Tohoku University*

JAEA-Review 2022-009, 73 Pages, 2022/06

JAEA-Review-2022-009.pdf:2.08MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2020. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2018, this report summarizes the research results of the "Basic research on the stability of fuel debris including alloy phase" conducted from FY2018 to FY2021 (this contract was extended to FY2021). Since the final year of this proposal was FY2021, the results for four fiscal years were summarized. The present study focus on fuel debris consisting of oxide phase and alloy phase generated by the high temperature chemical reaction between structure materials (SUS pipes, pressure vessels, etc.) and fuels (melted fuels, claddings components, etc.). We synthesize the simulated debris of UO-SUS system and UO-Zr(ZrO)-SUS system by high-temperature heat treatment, and measure their chemical property and dissolution behavior in water.

Release behaviors of elements from an Ag-In-Cd control rod alloy at temperatures up to 1673 K

Nagase, Fumihisa; Otomo, Takashi; Uetsuka, Hiroshi*

Nuclear Technology, 208(3), p.484 - 493, 2022/03

https://doi.org/10.1080/00295450.2021.1905472

An Ag-In-Cd control rod alloy was heated in argon or oxygen at 1073-1673 K for 60-3600 s and the release behavior of the elements was examined. Complete liquefaction of the alloy occurred between 1123 and 1173 K, and elemental release was quite limited below the liquefaction temperature. In argon, almost all of the Cd content was released within 3600 s at 1173 K and within 60 s at 1573 K, while the released fractions of Ag and In were 3% and 8%, respectively. In oxygen, the release of Cd, which was quite small at temperatures up to 1573 K, drastically increased to 30-50% at 1673 K for short periods. Releases of Ag and In were also small in oxygen under the examined conditions. Comparison with the experimental data suggests that conventional empirical release models may underestimate the Cd release at lower temperatures just after control rod failure in severe accidents.

Work hardening behavior of hot-rolled metastable FeCoNiAlTiMo medium-entropy alloy; In situ neutron diffraction analysis

Kwon, H.*; Harjo, S.; Kawasaki, Takuro; Gong, W.; Jeong, S. G.*; Kim, E. S.*; Sathiyamoorthi, P.*; Kato, Hidemi*; Kim, H. S.*

Science and Technology of Advanced Materials, 23(1), p.579 - 586, 2022/00

https://doi.org/10.1080/14686996.2022.2122868