著者

萩原 幸司 東田 賢二

出版者

公益社団法人 日本金属学会

雑誌

まてりあ (ISSN:13402625)

巻号頁・発行日

vol.54, no.2, pp.60-64, 2015 (Released:2015-02-01)

参考文献数

17

著者

前野 圭輝 田中 將己 吉村 信幸 白幡 浩幸 潮田 浩作 東田 賢二

出版者

一般社団法人 日本鉄鋼協会

雑誌

鉄と鋼 (ISSN:00211575)

巻号頁・発行日

vol.98, no.12, pp.667-674, 2012 (Released:2012-11-30)

参考文献数

31

被引用文献数

7 27

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In order to elucidate the mechanism behind the decrease in the brittle-to-ductile transition (BDT) temperature with the addition of Ni, impact tests and tensile tests were performed at various test temperatures from 130K to 320K with Ni added ultra-low carbon steels. The dependence of absorbed impact energy on temperature and the Ni content indicates that the BDT temperature was decreased with the increasing Ni content, which suggests that the dislocation mobility at low temperatures was increased with the Ni content. The yield stress which is also influenced by the dislocation mobility was decreased at low temperatures while it was increased at room temperature with the Ni content. The values of the activation volume and the effective stress were measured at several temperatures, and then the dependence of the activation energy for dislocation gliding on Ni content was obtained by extrapolating the relation between temperature and the multiplication of the activation volume and the effective stress to 0K. The activation energy was found to decrease with the increasing Ni content, which suggests that the dislocation mobility was increased with the addition of Ni. Discrete dislocation dynamics simulation was also performed in order to calculate the dependence of fracture toughness on temperature and the Ni content, and it was clarified that the BDT temperature is decreased by increasing dislocation mobility.

著者

金子 賢治 伊野家 浩司 佐藤 圭介 北脇 高太郎 東田 賢二 Ilke Arslan Paul A. Midgley

出版者

公益社団法人 日本金属学会

雑誌

まてりあ (ISSN:13402625)

巻号頁・発行日

vol.46, no.12, pp.786, 2007-12-01 (Released:2011-08-11)

参考文献数

4

著者

吾郷 真司 田中 照剛 横手 達夫 東田 賢二 小野寺 龍太

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.67, no.1, pp.34-39, 2003 (Released:2008-04-24)

参考文献数

1

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This study aims to give a mechanical explanation to manufacturing of metal (silver) foil in a traditional Japanese way in which the foils are put between Japanese papers and forged. It was clarified by forging tests carried out at various forging pressures that the forging pressure necessary for manufacturing silver foil is about 30 MPa, which is equal to one-tenth of the yield stress in a 90% rolled specimen. The test also showed that the plastic elongation of foil is of the order of 0.1% per forging (pressure is 30 MPa). This result suggests that the foil is not stretched by forging pressure, but by frictional tensile stress applied to the foil by the Japanese paper. Another test to measure the elastic property of paper showed that the Japanese paper was elongated by 0.5∼0.6% in the paper plane when it was compressed in the vertical direction at the pressure of 30 MPa. Considering the elastic strain of foil, the value of 0.5∼0.6% agreed well with the plastic elongation of foil of 0.1%. The forging tests also showed that the lower limit of foil thickness is dominated by the ability of paper not to adhere to the silver foil (removability); for example, it was 1 μm for some papers, but 0.4 μm for others.

著者

河村 能人 萩原 幸司 相澤 一也 木村 滋 古原 忠 東田 賢二 乾 晴行 奥田 浩司 中谷 彰宏 君塚 肇 中島 英治 大橋 鉄也

出版者

熊本大学

雑誌

新学術領域研究(研究領域提案型)

巻号頁・発行日

2011-04-01

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総括班の役割は、各計画研究と公募研究が緊密に連携して十分な研究成果が出せるように、本領域の組織的かつ効果的な運営と研究支援活動ならびに若手人材育成を図り、本領域の目的達成と次への展開に資することである。運営面での特徴は,①6つの部会と4つの事務局による効率的な運営、②量子線共同利用施設や共通試料提供等による研究支援、③若手人材育成への注力、④国際交流,異分野交流,産学官交流の推進である。総括班としての主な成果は、各種領域内会議による効果的な運営、研究支援による効率的な研究推進、領域内交流による連携推進、国内外シンポジウム等の開催による本領域のプレゼンス向上、若手研究者の活躍等である。