Inverse pole figure mapping of bulk crystalline grains in a polycrystalline steel plate by pulsed neutron Bragg-dip transmission imaging

Sato, Hirotaka*; Shiota, Yoshinori*; Morooka, Satoshi; Todaka, Yoshikazu*; Adachi, Nozomu*; Sadamatsu, Sunao*; Oikawa, Kenichi; Harada, Masahide; Zhang, S.*; Su, Y. H.; et al.

Journal of Applied Crystallography, 50(6), p.1601 - 1610, 2017/12

https://doi.org/10.1107/S1600576717012900

Microstructure and residual strain distribution in cast duplex stainless steel studied by neutron imaging

Su, Y. H.; Oikawa, Kenichi; Kawasaki, Takuro; Kai, Tetsuya; Shiota, Yoshinori*; Sato, Hirotaka*; Shinohara, Takenao; Tomota, Yo*; Harada, Masahide; Kiyanagi, Ryoji; et al.

JPS Conference Proceedings (Internet), 8, p.031015_1 - 031015_5, 2015/09

https://doi.org/10.7566/JPSCP.8.031015

In this study, neutron imaging experiment was performed using NOBORU, BL10 of MLF at J-PARC. Four kinds of cast duplex stainless steel with ferrite and austenite microstructure were studied here, which were produced by different casting method at different temperature. Firstly, two-dimensional scintillation detector using wavelength-shifting fibers with pixel size of 0.52 mm 0.52 mm and illuminated area 55 mm 55 mm was used for data collection. Then, measurement by Micro Pixel Chamber based neutron imaging detector having higher spatial resolution about 0.2 mm was conducted. Data analysis code RITS (Rietveld Imaging of Transmission Spectra) will be used for microstructure including crystalline phase, lattice strain, crystallite size, texture evaluation.

Formation of texture and intergranular strain in cold rolled austenitic plate

Suzuki, Hiroshi; Holden, T. M.*; Clausen, B.*; Shiota, Yoshinori*; Tomota, Yo*

no journal, , 

In this study, the textures in cold rolled 316 type austenitic stainless plate with 25 % and 75 % reduction as well as the as-received plate were measured using neutron diffraction. The texture was progressed with increase of reduction rate and the typical texture in cold rolling was observed. In addition, the intergranular strains of each reflection at 25 % reduction were also measured. The largest variations of intergranular strain were observed in 200 reflection. Relation of intergranular strains among 111, 200 and 220 reflections is very similar with that with uniaxial deformation reported in previous studies.

Bulk texture evaluation for steels using various neutron diffractometers

Xu, P. G.; Suzuki, Hiroshi; Metoki, Naoto; Shiota, Yoshinori; Suzuki, Tetsuya*; Yin, F. X.*; Akita, Koichi

no journal, , 

It is well known that the neutron diffraction is suitable to evaluate the crystallographic textures of various bulk materials while the measured texture results are partially dependent on the diffractometer used. Since JAEA has several neutron diffractometers for texture measurement, including RESA, RESA-II and MUSASI (JAEA), the quantitative comparison among bulk textures of several selected samples is helpful to further optimize the measurement conditions and ensure the users to get reliable results. By proper selection of neutron beam size and collimator size, the evaluation reliability of MUSASI was improved so that it may be utilized to reliably measure neutron textures of various materials.

Time-of-flight neutron Bragg-edge imaging for microstructure of bent steel plates

Su, Y. H.; Oikawa, Kenichi; Harada, Masahide; Shinohara, Takenao; Kai, Tetsuya; Zhang, S.*; Parker, J. D.*; Sato, Hirotaka*; Shiota, Yoshinori*; Tomota, Yo*

no journal, , 

no abstracts in English

Actual situation of profile analysis in neutron engineering diffractometer

Shiota, Yoshinori

no journal, , 

no abstracts in English

Thermal expansion behavior of iron carbide FeC

Harjo, S.; Shiota, Yoshinori*; Yonemura, Masao*; Tomota, Yo*; Kamiyama, Takashi*; Umemoto, Minoru*

no journal, , 

Iron Carbide FeC (called "cementite") is an important phase for engineering steels. The amount and shape of cementite determine mechanical and thermal properties of the steels. Cementite is also suggested as the major phase in the inner core of the centre of the earth. However, since the cementite single-phase specimen was so difficult to prepare, its physical properties have not been examined well. Recently, the preparation of cementite bulky specimen has been performed by using plasma-sintering with mechanical milling. The lattice parameters of the prepared bulky pure cementite and Mn-alloyed cementite were measured at VEGA-KENS (Time-of-Flight neutron powder diffractometer) in a temperature range from room temperature to 673 K, to determine their thermal expansion coefficients. Results of the measurements will be presented.

In site strain measurement of ferrite matrix in cold drawn pearlite steel during tensile loading by neutron diffraction

Shiota, Yoshinori; Tomota, Yo*; Harjo, S.; Kamiyama, Takashi*

no journal, , 

In our previous report on in site neutron diffraction during tensile loading for heavily drawn ferrite and pearlite steels, two points were made clear. One is stress partitioning between the ferrite matrix and the cemente phases for the patented pearlite steel. Another one is the nonlinear elastic deformation above the external stress of 3GPa in the heavily drawn pearlite steel. However, these measurements were performed by the angler dipersion mehteod for {110} planes along the tensile direction, the effect of texture has not been considered. Hence, diffraction from {hkl} planes both in the tensile and transverse directions were observed in this study. Beacuse strong {hkl}110 fiber formed during severe deformation, the strain behavior was similar to that deformation of {hkl}110 single crystal. As the axis of principal stress is 110 lattice direction, transverse {hkl} deformation in cubic system possessed elastic anisotropy.