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Harjo, S.; 川崎 卓郎; 友田 陽*; 柴田 曉伸*; 辻 伸泰*; 相澤 一也
no journal, ,
Two topics done at TAKUMI of MLF, J-PARC are introduced. Evolutions of dislocation characteristics during tensile deformation in a lath martensitic steel have been possible to be monitored by applying the convolutional multiple whole profile (CMWP) fitting method, to understand the strengthening behavior of metallic material with extremely high dislocation density induced during the material preparation. This method is possible to be applied to understand the deformation behaviour of bulk nano materials. A new sample environmental device for simulating Thermo-Mechanical Controlling Process of materials (thermec-mastor) has been installed in a collaboration between a research group in Kyoto University and TAKUMI. This new device is designed to heat and cool a specimen rapidly, and to apply compression with a high strain rate. The basic design and the commissioning progress of the thermec-mastor will be briefly introduced together with the first neutron diffraction data on steels.
菊地 龍弥
no journal, ,
In recent years, we have been developing a method for calculating the real space functions, G(r,t) and G(r,E), from the dynamic structure factor, S(Q,E). G(r,t) is van Hove's space-time correlation function which is a function in real space and time. G(r,E) is Fourier-transformed function of S(Q,E) only about spatial axis. Those functions are important to express local motions of atoms and molecules directly. However, the calculations of real-space functions have been hardly performed even though it is so easy mathematically, because it requires spectrum in both high resolution and wide range in Q-E space, which has been difficult to measure in the past. By the progress of the recent neutron sources and spectrometers, the measurements with wide range and high resolution in Q-E space are becoming easy. We measured high-resolution S(Q,E) using AMATERAS spectrometer installed at J-PARC and calculated G(r,t) and G(r,E). We used the maximum entropy method to lower the bias of truncation errors for the calculation of G(r,t). I will introduce the current status and future potential of G(r,t) and G(r,E) calculations, and the results of liquid, glass and crystal.
川崎 卓郎; 稲村 泰弘; 伊藤 崇芳*; 中谷 健; Harjo, S.; Gong, W.; 相澤 一也
no journal, ,
In this study, the lattice strain and the domain characteristic of a piezoelectric material under static and cyclic electric fields were studied by time-of-flight neutron diffraction. The diffraction intensities from PZT-based ceramics in the multilayer type piezoactuator were measured using the Engineering Materials Diffractometer TAKUMI at MLF in J-PARC. The intensities in both the axial and the transversal directions of the actuator were measured simultaneously by 
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detector banks. The collected data were divided based on the voltage and the phase conditions of applied electric field and were converted to diffraction patterns using the condition filtering data reduction method developed in J-PARC. The peak shifts and the intensity variations of diffraction peaks according to the applied field were found in the patterns. The responses of the lattice and the domain to the field were successfully observed.
稲村 泰弘; 中谷 健
no journal, ,
MLFの装置で使用されているソフトウェアは、主に装置制御とデータ処理に大別される。それらの開発はMLF内でのソフトウェアの共有化を目指し進められており、装置制御ではIROHAと呼ばれるフレームワークが、データ処理や解析コードの開発用フレームワークとして万葉ライブラリがある。最近IROHAのアップデートにより、ウェブブラウザ経由でデバイスを制御できるようになった。MLFの一部の非弾性散乱装置において、その新しい装置制御フレームワークIROHA2の導入と実用化が進められている。一方、万葉ライブラリを基礎とした空蝉パッケージも進展があった。特にイベント記録型データのデータ処理にイベントフィルタリング機能が追加され、イベントデータとして記録された試料やデバイスの状態の情報によって中性子散乱データを分割し解析処理を行う仕組みが実用化となった。本講演では、非弾性散乱装置に新しく導入されたIROHA2の紹介と、イベントフィルタリングによって可能となった測定手法を中心に紹介する。
中島 健次
no journal, ,
J-PARCの物質・生命科学実験施設には、6つの非弾性散乱装置が稼働中、あるいは、建設中である。それらは、4つのチョッパー型分光器、四季、HRC、AMATERAS、POLANO、逆転配置型分光器DNA、それに、スピンエコー装置VINS ROSEである。これらで行われる研究について発表する。