著者

田中 泰彦

出版者

一般社団法人 ターボ機械協会

雑誌

ターボ機械 (ISSN:03858839)

巻号頁・発行日

vol.25, no.5, pp.250-261, 1997-05-10 (Released:2011-07-11)

参考文献数

48

著者

岩舘 忠雄 田中 泰彦 竹俣 裕行

出版者

一般社団法人 日本高圧力技術協会

雑誌

圧力技術 (ISSN:03870154)

巻号頁・発行日

vol.23, no.6, pp.286-293, 1985-11-25 (Released:2010-08-05)

参考文献数

2

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The high pressure reactors are sometimes autofrettaged to have the life elongated which is based on the highly compressive residual stress near the bore surface. In this study, to evaluate the material degradation based on the autofrettaged strain, the effect of autofrettage on the fracture toughness behavior was investigated using the 3.5% Ni-Cr-Mo-V steels.(1) When the prestrain increases, the fracture toughness decreases, especially in the higher yield strength steel. The decrease of the fracture toughness of the material was observed in the prestrain range larger than 5 percent for the about 1000MPa yield strength steel and than 2 percent for the about 1150 MPa yield strength steel.(2) The material resistance to ductile fracture, that is, tearing modulus TJ decreases in the same prestrain ranges as those of the fracture toughness.(3) However, the autofrettaged material taken out of the actual pressure reactor shows no decrease of the fracture toughness and the tearing modulus which is caused by the small amount of the prestrain, less than about 1 percent even in the 100 percent autofrettaged reactors.

著者

田中 泰彦

出版者

長崎大学

巻号頁・発行日

2007

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博士論文

著者

東 司 田中 泰彦 石黒 徹

出版者

社団法人日本鉄鋼協会

雑誌

鐵と鋼 : 日本鐡鋼協會々誌 (ISSN:00211575)

巻号頁・発行日

vol.76, no.5, pp.783-790, 1990-05-01

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Grain refining behavior during austenitizing of 3.5%Ni-Cr-Mo-V turbine rotor shaft steel was investigated. Special attention was paid on the effect of Ni content and role of fine carbide precipitates on the austenite transformation and migration of the acicular austenite grain boundary. The microscopic observation of grain refining behavior reveals the following results. (1) The grain refining of 3.5%Ni-Cr-Mo-V steels during austenitizing occurs through two stages. The first stage is austenite transformation which γ-phases succeed to the acicular bainitic ferrite structure. The second stage is the formation of equiaxed grain at higher temperatures by the migration of grain boundary of the acicular austenite. (2) Driving force of the grain boundary migration in the second stage is considered to be the high density defects in the acicular austenite. (3) Increase of Ni content stabilize the acicular γ-phases up to higher temperatures. This decreases the formation of equiaxed grain due to the migration of acicular austenite grain boundary. (4) Increase of V content makes the grain refining difficult because the fine carbide precipitate such as VC works as a barrier against the grain boundary migration required for the formation of equiaxed grain.

著者

吉岡 洋明 伊藤 裕道 田中 泰彦 池田 保 美

出版者

社団法人日本鉄鋼協会

雑誌

鐵と鋼 : 日本鐡鋼協會々誌 (ISSN:00211575)

巻号頁・発行日

vol.89, no.6, pp.705-710, 2003-06

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To meet the requirements for optimum utilization of power station sites and economic realization of coal fired thermal units, tandem compound 60 Hz 1000 MW large thermal units were developed. One of the most critical items was development of a large-size high strength generator rotor forging with comparable toughness to the conventional rotor forging. Based on the investigation results of existing rotor forging, chemistry optimization was conducted within the specification of conventional turbine generator and low pressure rotor forging by using lab oratory heat materials and 0.28%C-0.25%Mn-4%Ni-1.75%Cr-0.4%Mo-0.12%V high purity steel was selected for the candidate material. Double tempering heat treatment of 550℃ and 580℃ was also developed for increasing the yielding ratio of 0.02% yielding stress to tensile strength to meet the requirements of mechanical properties. According to those laboratory studies, one trial rotor forging with the same diameter as production ones was successfully produced.

著者

藤ヶ谷 剛彦 田中 泰彦 中嶋 直敏

出版者

The Electrochemical Society of Japan

雑誌

電気化学および工業物理化学 : denki kagaku (ISSN:13443542)

巻号頁・発行日

vol.78, no.1, pp.2-15, 2010-01-05

被引用文献数

4

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One of the key issues in the utilization of carbon nanotubes (CNTs) for basic researches as well as their applications is to develop a methodology to solubilize/disperse them in solvents. In this review articles, we first summarize individual solubilization of single-walled carbon nanotubes (SWNTs) in solvents using surfactants, polycylcic aromatic molecules, DNA and condensed polymers. We then describe a novel method determining the electronic states of individually dissolved SWNTs having an own chirality index based on the analysis of Nernst equation. We also introduce our recent approach toward the fabrication of a novel catalyst for fuel cell that works at a nonhumid atmosphere using solubilized CNTs as material.