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Harjo, S.; 川崎 卓郎; Gong, W.; 相澤 一也
Journal of Physics; Conference Series, 746(1), p.012046_1 - 012046_7, 2016/10
被引用回数：9 パーセンタイル：94.05(Physics, Nuclear)In situ neutron diffraction during tensile deformation of an as-quenched lath martensitic 22SiMn2TiB steel, was performed using a high resolution and high intensity time-offlight neutron diffractometer. The characterizations of dislocations were analyzed using the classical Williamson-Hall (cWH) and modified Williamson-Hall (mWH) plots on the breadth method, and the convolutional multiple whole profile (CMWP) fitting method. As results, the dislocation density as high as 10
m
in the as-quenched martensitic steel was determined. The dislocation density was found to decrease qualitatively with plastic deformation by the cWH and mWH plots, but hardly to change by the CMWP method. The scanning transmission electron microscopy observation supported the results of the latter method. In the CMWP method, the parameter 
that represents the arrangement of dislocations was found to decrease rapidly where a very high work hardening was observed.
川崎 卓郎; Harjo, S.; Gong, W.; 相澤 一也
Journal of Physics; Conference Series, 746(1), p.012044_1 - 012044_6, 2016/10
被引用回数：2 パーセンタイル：67.42(Physics, Nuclear)The microstructure of the metallic material is widely investigated in order to understand mechanical properties of the material by line profile analysis for X-ray and neutron diffraction data. Neutron diffraction has an advantage for obtaining averaged information of the microstructure inside the bulky material owing to its high transmittance. Further, the variation of the microstructure in the material during mechanical process is able to be observed by in-situ measurements. The Convolutional Multiple Whole Profile (CMWP) fitting method is a state of the art technique for line profile analysis. The dislocation characteristics are evaluated from the shape of the peak profile including the tail by this technique. In this study, the dislocation characteristics in martensitic steels during tensile deformation were studied by in-situ neutron diffraction measurement using the Engineering Materials Diffractometer TAKUMI at J-PARC through line profile analysis using the CMWP fitting method.
篠原 武尚; 甲斐 哲也; 及川 健一; 瀬川 麻里子; 原田 正英; 中谷 健; 大井 元貴; 相澤 一也; 佐藤 博隆*; 加美山 隆*; et al.
Journal of Physics; Conference Series, 746, p.012007_1 - 012007_6, 2016/00
被引用回数：59 パーセンタイル：99.77(Physics, Nuclear)パルス中性子イメージング専用装置「螺鈿」がJ-PARCの物質生命科学実験施設(MLF)に建設され、2014年11月にファーストビームを受け入れた後、装置調整と試験測定を実施中である。この装置の目的は、短パルス中性子源から得られるパルス中性子ビームの特徴を活かして、近年注目されているエネルギー分析型中性子イメージング技術を実用化し、応用研究を世界に先駆けて実施することにあり、同時に日本における最先端の中性子イメージング装置としての役割を果たすことにある。本発表では、「螺鈿」の現状について説明するとともに、コミッショニングの状況と応用研究の実施例について報告する。
Harjo, S.; 川崎 卓郎; Gong, W.; 相澤 一也
no journal, ,
The Engineering Materials Diffractometer "TAKUMI" has been built at BL19 in Materials and Life Science Experimental Facility, J-PARC and is operated to promote scientific and industrial studies in various areas such as materials science and engineering and mechanical engineering. TAKUMI was designed not only to have high resolution providing high accuracy in lattice strain, to have also high intensity enabling to time transient diffraction per seconds or less. The construction of BL19 TAKUMI was completed at the beginning of 2009. The operation was terminated during 2011 due to the damages caused by the Tohoku earthquake, but was restarted on 2012 after the repairing and commissioning within a year. Current status of TAKUMI will be briefly introduced; (1) instrument specifications, (2) covering applications, (3) unique sample environmental devices and available experiments, (4) research examples and (5) new challenges and upgrading plans.
