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徐 平光; Harjo, S.; 伊藤 崇芳*; 森井 幸生*; Gong, W.; 鈴木 裕士; 秋田 貢一; 鈴木 徹也*; 友田 陽; Lutterotti, L.*
JPS Conference Proceedings (Internet), 8, p.031022_1 - 031022_6, 2015/09
The current status of bulk texture measurements both using angle dispersive neutron diffraction and time-of-flight neutron diffraction at JAEA was briefly reviewed, then the effect of sample orientation coverage in the time-of-flight neutron diffraction on the reliability of reconstructed pole figure on the reliability of reconstructed pole figure was simply compared after the simultaneous Rietveld texture analysis. The similar texture results obtained at different orientation coverage levels suggests that it is possible to reduce the sample rotation times reasonably during the bulk texture measurement.
徐 平光; 星川 晃範*; 石垣 徹*; 鈴木 徹也*; 秋田 貢一; 森井 幸生*; 林 眞琴*; Lutterotti, L.*
no journal, ,
For most metallic materials, in order to realize good balance among strength, ductility, toughness and formability, it is very important to optimize their microstructures and crystallographic textures as well as their alloy compositions. The time-of-flight neutron diffraction enables to measure various whole diffraction patterns of a textured material simultaneously at different scattering angles using different neutron detectors. In this presentation, the current status and its prospect of bulk texture evaluation technique using iMATERIA time-of-flight neutron diffractometer will be reported, including Omega-axis rotatable sample exchanger for rapid measurements and Omega/Kai 2-axes rotatable goniometer for in situ texture evolution studies. Moreover, the Rietveld texture analysis technique implemented in MAUD (Materials Analysis Using Diffraction) has been employed here to overcome the beam shielding effect of environmental equipment on texture measurement.
徐 平光; 星川 晃範*; 石垣 徹*; 鈴木 徹也*; 秋田 貢一; 森井 幸生*; 林 眞琴*; Lutterotti, L.*
no journal, ,
The rapid texture measurement of bulk metallic materials is required not only for the precise formability control of commercial sheet products, but also for the thermomechanical process optimization of new materials. Different with the angle dispersive neutron diffraction with a single-tube/1-D neutron detector, the time-of-flight neutron diffraction enables to measure various whole diffraction patterns of a textured material simultaneously at different scattering angles using different neutron detectors. At J-PARC center, iMATERIA time-of-flight neutron diffractometer was employed to establish a reliable technical environment for rapid bulk texture measurements. In order to reduce the measurement time and improve the reliability, the proper refinement of detector stereographic coverage range and the corresponding increment of independent diffraction patterns from different sample orientation are under investigation.
徐 平光; 諸岡 聡; 山本 和喜; Vogel, S. C.*; Lutterotti, L.*; 菖蒲 敬久
no journal, ,
Because of large spot size and high penetrability, neutron diffraction can acquire the average orientation information of a bulk polycrystalline sample and monitor the microstructure and/or texture evolutions. Though many new neutron facilities with higher thermal beam flux have been established for residual stress and texture measurements, neutron diffraction facilities attached at a conventional research reactor like the Japan Research Reactor No.3 (JRR-3) are still being expected to support broader neutron diffraction application studies not limited by metals, alloys, ceramics, composite materials, and even geological materials. In this oral presentation, the newest experimental results from a round robin texture measurement test of international standard limestone will be formally reported and the related discussion and future prospect will be involved.
徐 平光; Harjo, S.; 小貫 祐介*; 佐藤 成男*; Lutterotti, L.*; Vogel, S. C.*; Liss, K.-D.*; 富田 俊郎*
no journal, ,
For polycrystalline materials, textures as their crystallographic orientation feature have been paid broad attention because of their important effects on mechanical and physical characteristics. Besides metals and ceramics, the widespread applications of textures involving sheet forming simulation, additive manufacturing, minerals, and rocks have also demonstrated this status. Different with the electron backscattering diffraction (EBSD) and the X-ray diffraction (XRD) for surface texture analysis, the neutron diffraction thanks to the excellent penetrability and the coarse beam spot of thermal neutrons can collect high statistical diffraction pattens, valuable for deeply investigating the microstructure change and the characteristic response of polycrystalline materials. Through the Rietveld texture analysis process combined with other profile-analysis-related material parameters (e.g. stress tensor, phase fraction, dislocation density and/or coherent size), the large-scale neutron diffractometers TAKUMI and iMATERIA with good instrumental resolution (
d/d) and high beam flux have higher measurement efficiency, promoting that the precise evaluation of microstructures and related materials parameters of advanced materials. Recently, weak diffraction patterns step-by-step collected in very short time from the RESA angle dispersive neutron diffractometer at JRR-3 have been utilized to realize the precise texture evaluation of various polycrystalline materials. Our international round robin activity for texture analysis confirms that, Rietveld texture analysis using MAUD software may be recommended as a standard bulk texture analysis method, regardless of the neutron source types of steady reactor source or time-pulsed source.
