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小山 元道*; 山下 享介*; 諸岡 聡; Yang, Z.*; Varanasi, R. S.*; 北條 智彦*; 川崎 卓郎; Harjo, S.
鉄と鋼, 110(3), p.205 - 216, 2024/02
被引用回数：0
deformation experiments with cold-rolled and intercritically annealed Fe-5Mn-0.1C steel were carried out at ambient temperature to characterize the deformation heterogeneity during L
ders band propagation. Deformation band formation, which is a precursor phenomenon of Lders band propagation, occurred even in the macroscopically elastic deformation stage. The deformation bands in the Lders front grew from both the side edges to the center of the specimen. After macroscopic yielding, the thin deformation bands grew via band branching, thickening, multiple band initiation, and their coalescence, the behavior of which was heterogeneous. Thick deformation bands formed irregularly in front of the region where the thin deformation bands were densified. The thin deformation bands were not further densified when the spacing of the bands was below 
10 
m. Instead, the regions between the deformation bands showed a homogeneous plasticity evolution. The growth of the thin deformation bands was discontinuous, which may be due to the presence of ferrite groups in the propagation path of the deformation bands. Based on these observations, a model for discontinuous Lders band propagation has been proposed.
ders band propagation in an Fe-5Mn-0.1C medium Mn steel clarified through 
scanning electron microscopy小山 元道*; 山下 享介*; 諸岡 聡; Yang, Z.*; Varanasi, R. S.*; 北條 智彦*; 川崎 卓郎; Harjo, S.
ISIJ International, 62(10), p.2043 - 2053, 2022/10
被引用回数：7 パーセンタイル：32.54(Metallurgy & Metallurgical Engineering) deformation experiments with cold-rolled and intercritically annealed Fe-5Mn-0.1C steel were carried out at ambient temperature to characterize the deformation heterogeneity during Lders band propagation. Deformation band formation, which is a precursor phenomenon of Lders band propagation, occurred even in the macroscopically elastic deformation stage. The deformation bands in the Lders front grew from both the side edges to the center of the specimen. After macroscopic yielding, the thin deformation bands grew via band branching, thickening, multiple band initiation, and their coalescence, the behavior of which was heterogeneous. Thick deformation bands formed irregularly in front of the region where the thin deformation bands were densified. The thin deformation bands were not further densified when the spacing of the bands was below 10 m. Instead, the regions between the deformation bands showed a homogeneous plasticity evolution. The growth of the thin deformation bands was discontinuous, which may be due to the presence of ferrite groups in the propagation path of the deformation bands. Based on these observations, a model for discontinuous Lders band propagation has been proposed.
高橋 正光; 米田 安宏; 井上 博胤*; 山本 直昌*; 水木 純一郎
Japanese Journal of Applied Physics, Part 1, 41(10), p.6247 - 6251, 2002/10
被引用回数：55 パーセンタイル：85.24(Physics, Applied)III-V族半導体の結晶成長の研究を目的に、MBE装置と組み合わせた表面X線回折計を製作し、放射光施設SPring-8の実験ステーションBL11XUに設置した。成長室の壁の一部に、X 線の窓材としてBeを用いたことで、真空槽の外からX線を照射し、散乱X線を真空槽外に導いて、その場X線回折測定を行うことができる。本装置のX線回折計は、単結晶構造解析用の四軸回折計と同等の機能を有しており、広範囲の逆格子空間の強度測定に基づいた、表面原子の三次元座標の決定を可能にする。本論文では、GaAs(001) 清浄表面において、(2
4)
2構造と一致する回折強度分布が得られたことを示す。さらに、成長中のX線回折強度を実時間測定し、成長過程の動的な解析ができることを示す。GaAs(001)上のホモエピタキシャル成長中のX線回折では、RHEED振動と同様の強度変化が明瞭に観察された。X線の場合は多重散乱が無視できるので、解析の精密化が期待できる。
吉田 廣*; 阪井 英次
JAERI-M 82-191, 72 Pages, 1982/12
本報告は半導体検出器により得られた、環境ガンマ線スペクトル・データを解析するためのプログラムについて述べたものである。これらはマルチチャネル波高分析器(MCA)とミニコンピュータより成るシステムにより、ガンマ線スペクトルのデータを自動的に収集し解析するために作製したプログラムを更に拡張して本目的のために開発したものである。拡張したプログラムの主なものは(1)MCAメモリ内のデータを直接解析して光電ピークの面積を算出し、ディスク上のライブラリ・データ中の、光電ピーク・エネルギーと核種により定まるそれぞれの係数をそれぞれのピ-ク面積の値に乗じ、存在する核種の放射能強度およひ空間線量率を算出する。(2)ディスクに記入されたMCAのデータに対して同様の解析を行い、結果をディスクに記入する。(3)これらのデータの積算と解析を平行して自動的に行うもの、等である。
ders band propagation in a medium Mn steel小山 元道*; 山下 享介*; 諸岡 聡; Yang, Z.*; Varanasi, R.*; 北條 智彦*; 川崎 卓郎; Harjo, S.
no journal, ,
The micro-deformation of an Fe-5Mn-0.1C medium Mn steel consisting of face-centered cubic and body-centered cubic phases was characterized through multi-scale in situ scanning electron microscopy. Specifically, multiscale in situ back-scatter electron imaging coupled with ex situ electron backscatter diffraction measurements was conducted under tensile testing. The Fe-Mn-C alloy showed macroscopically localized deformation (i.e., Lders deformation), and the deformation-localized region consisted of multiple find deformation bands. The hierarchical structure of the deformation bands initiated from a specimen side edge and propagated to the other side edge. More microscopically, the plastic deformation preferentially progressed in a face-centered cubic phase, and temporarily stopped when the fine deformation band encountered a group of body-centered cubic grains, which resulted in zigzag propagation of the fine deformation bands. Through coalescence of fine deformation bands, a thick macroscopic deformation band formed. By repetition of the micro-deformation process, the thick deformation band front moved along the tensile direction from an end of the gauge portion to the other end.
