In-house texture measurement using a compact neutron source

Abstract

In order to improve the instrumental accessibility of neutron diffraction techniques, many emerging compact neutron sources and in‐house neutron diffractometers are being developed, even though the precision level of neutron diffraction experiments performed on such instruments was thought to be incomparable with that of large‐scale neutron facilities. As a challenging project, the RIKEN accelerator‐driven compact neutron source (RANS) was employed here to establish the technical environment for texture measurements, and the recalculated pole figures and orientation distribution functions of an interstitial‐free steel sheet obtained from RANS were compared with the results from another two neutron diffractometers well established for texture measurement. These quantitative comparisons revealed that the precise neutron diffraction texture measurement at RANS has been realized successfully, and the fine region division of the neutron detector panel is invaluable for improving the stereographic resolution of texture measurements. Moreover, through selectively using the parts of the obtained neutron diffraction patterns that exhibit good statistics, the Rietveld texture analysis improves the reliability of the texture measurement to a certain extent. These technical research results may accelerate the development of other easily accessible techniques for evaluation of engineering materials using compact neutron sources, and also help to improve the data‐collection efficiency for various time‐resolved scattering experiments at large‐scale neutron facilities.

Non-destructive texture characterization by a robot-arm-driven X-ray diffractometer

“…Pole figure determination with X-rays is routine, and results can be obtained within a few hours; neutron diffraction is more specialized. X-rays are available in-house, whereas neutrons require large-scale user facilities with limited access unless a RIKEN-type compact neutron source is available, as reported by Xu et al (2020). Neutron diffraction should be used to measure samples that cannot be measured with X-rays.…”

Development and Dissemination of Compact Neutron Systems and of Non-destructive Measurement Technology for Infrastructures

“…め，設計開発を開始し，全長 5 m 標的遮蔽 5 ton 以 下を実現した．なお，RANS-II は据置型のものづ くり現場利用小型中性子源としてさらに up-grade した陽子線ライナックを基にしたものがハンガリ ーの Mirrotron 社で現在導入中である． ここで，小型中性子源システムで可能な中性子 散乱計測例の参考になると思い，現在 RANS で実 施可能な実験をリストアップしてみる． (1) 中性子透過イメージング [4] (2) 中性子回折 [5,6] (3) 中性子誘導即発ガンマ線分析(NPGAA) [7] (4) 放射化分析 ( 5) 高速中性子透過イメージング [8] (6) 高速中性子散乱イメージング [9] (7) 中性子小角散乱(茨城大学小泉教授らによ る ib-SANS 装置) ( 8) 中性子干渉イメージング(東北大 多元研 百生教授らによる)[10] (9) 偏極中性子実験実験 [11] なお，(2…”