量研学術機関リポジトリ「QST-Repository」は、国立研究開発法人 量子科学技術研究開発機構に所属する職員等が生み出した学術成果（学会誌発表論文、学会発表、研究開発報告書、特許等）を集積しインターネット上で広く公開するサービスです。 Welcome to QST-Repository where we accumulates and discloses the academic research results(Journal Publications, Conference presentation, Research and Development Report, Patent, etc.) of the members of National Institutes for Quantum Science and Technology.
Thank you very much for using our website. On the 11th of March 2019, this site was moved from our own network server to the JAIRO Cloud network server. If you previously bookmarked this site, that bookmark will no longer work. We would be grateful if you could bookmark the website again. Thank you very much for your understanding and cooperation.
An irradiation effect of a Nd-Fe-B permanent magnet by fast neutrons having a central energy of 10 MeV was investigated experimentally. The sample magnet (NEOMAX-39SH) had a rectangular shape of 25 mm 25 mm and 5 mm thick. The measured magnetic flux density decreases at the center of the sample magnets were 0.6%, 6.9%, 25.2% and 47.3% after continuous irradiation of 1.1 kGy, 3.7 kGy, 5.6 kGy and 7.4 kGy, respectively. On the other hand, the decrease due to non-continuous irradiation, in which the magnet was irradiated at 3.7 kGy firstly, and then irradiated again at 3.7 kGy 9 months later, was 14% smaller than that of continuous irradiation, even for the same total dose. The temperature coefficient of the magnetization did not change with the neutron irradiation. Some kinds of radioactive materials, such as 147Nd, 151Pm, and 54Mn, were detected in the magnet after irradiation.
雑誌名
Nuclear Instruments & Methods in Physics Research Section B
Irradiation effects of a 10 MeV neutron beam on a Nd-Fe-B permanent magnet
