2021 Fiscal Year Annual Research Report
Crystal orientation dependence of irradiation-induced hardening in structural materials for nuclear applications
| Project/Area Number |
19K15477
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| Research Institution | The University of Tokyo |
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Principal Investigator |
楊 会龍 東京大学, 大学院工学系研究科(工学部), 特任助教 (10814254)
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| Project Period (FY) |
2019-04-01 – 2022-03-31
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| Keywords | Irradiation hardening / Orientation / Texture / Deformation / Zr-based alloy / ODS steel |
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| Outline of Annual Research Achievements |
Previous studies about irradiation hardening have been conducted commonly based on an assumption that the material has a random microstructure. Consequently, the effect of hardening is homogeneous. However, the microstructure of many practical components in nuclear reactors is not random but inhomogeneous, which may lead to an inhomogeneous irradiation hardening. In this study, the crystal orientation dependency of irradiation hardening in structural materials for nuclear applications was studied.
In FY2019, the method was developed to correlate the irradiation hardening to its crystal orientation in hexagonal close packed (hcp) latticed Zr-based alloys and body-centered cubic (bcc) latticed oxide dispersion strengthening (ODS) steel, with the combined application of ion-accelerator irradiation, nano-indentation test, and electron backscattering diffraction analyses. In FY2020, the effect of microstructure such as grain boundary and second phase particles on the irradiation hardening was explored. In FY2021, the effect of irradiation dose and the type of irradiation defects on the inhomogeneous irradiation hardening in Zr-based alloys was investigated.
Obvious crystal orientation dependent irradiation hardening was confirmed in both hcp-Zr alloys and bcc-ODS steels. In hcp-Zr, the hardening was sensitive to the crystal orientation, however in bcc-ODS steel, the hardening was related to the inhomogeneous grain structure with a great grain aspect ratio. This study provided new insights for understanding the inhomogeneous irradiation hardening in in-reactor core components.
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Research Products
(2 results)
