Effects of dislocation arrangement and character on the work hardening of lath martensitic steels

Dannoshita, Hiroyuki*; Hasegawa, Hiroshi*; Higuchi, Sho*; Matsuda, Hiroshi*; Gong, W.; Kawasaki, Takuro; Harjo, S.; Umezawa, Osamu*

Scripta Materialia, 236, p.115648_1 - 115648_5, 2023/11

https://doi.org/10.1016/j.scriptamat.2023.115648

Work hardening behavior of dual phase copper-iron alloy at low temperature

Yamashita, Takayuki*; Koga, Norimitsu*; Kawasaki, Takuro; Morooka, Satoshi; Tomono, Shohei*; Umezawa, Osamu*; Harjo, S.

Materials Science & Engineering A, 819, p.141509_1 - 141509_10, 2021/07

https://doi.org/10.1016/j.msea.2021.141509

Neutron diffraction mapping measurement for Japanese nails in the ancient and present days

Yamashita, Takayuki; Harjo, S.; Umezawa, Osamu*; Kawasaki, Takuro

JPS Conference Proceedings (Internet), 33, p.011063_1 - 011063_6, 2021/03

https://doi.org/10.7566/JPSCP.33.011063

Role of retained austenite in low alloy steel at low temperature monitored by neutron diffraction

Yamashita, Takayuki; Morooka, Satoshi; Harjo, S.; Kawasaki, Takuro; Koga, Norimitsu*; Umezawa, Osamu*

Scripta Materialia, 177, p.6 - 10, 2020/03

https://doi.org/10.1016/j.scriptamat.2019.10.002

In-situ neutron diffraction during tensile under low temperature in low alloy steel containing metastable austenite

Yamashita, Takayuki; Morooka, Satoshi; Harjo, S.; Koga, Norimitsu*; Umezawa, Osamu*

no journal, , 

Volume fraction, phase stresses and crystal orientation in low alloy steel containing metastable austenite were investigated using by in-situ neutron diffraction during tensile under low temperatures. The martensite showed much higher phase stress than the other phases at each test temperatures. The phase stresses of ferrite matrix plus bainite and martensite increased as decreasing test temperature. The austenite phase stress was constant as increased applied true stress at low temperatures. It's suggested that austenite transformed to martensite prior to plastic deformation. The austenite which 111 direction parallel to tensile direction (111-A) is most stable at 293 K. At low temperatures, the 111-A transformed to martensite at early stage of deformation. The relative integrated intensity of 111-A was constant at later stage of deformation. It means that stable 111-A do not transformed to martensite during homogeneous deformation also at low temperatures.

JAEA's technical experiences and lessons learned for environmental remediation of Fukushima, 4; Technical supports for local governments

Sudo, Tomoyuki; Ishikawa, Hiroyasu; Uesaka, Takahiro*; Sonoda, Takashi; Ishikawa, Nobuyuki*; Niizato, Tadafumi; Mikake, Shinichiro; Aoki, Isao; Ishizaki, Nobuhiro; Imamura, Hiroaki; et al.

no journal, , 

JAEA is working the decontamination activity for the environmental remediation of Fukushima. In this activity, I support the decontamination activity for local governments to devise a decontamination plan and actually decontaminate. In this report, 1 introduce the technical knowhow for the decontamination activity of a house.

Investigation of deep levels in diamond based radiation detector by transient charge spectroscopy with focused heavy ion microbeam

Ando, Yushi*; Kambayashi, Yuya*; Kada, Wataru*; Onoda, Shinobu; Makino, Takahiro; Sato, Shinichiro; Umezawa, Hitoshi*; Mokuno, Yoshiaki*; Shikata, Shinichi*; Hanaizumi, Osamu*; et al.

no journal, , 

A transient spectroscopy analysis of pulse signals induced by heavy ion micro probe was applied for chemical vapor deposition (CVD) diamond-based radiation detector to investigate the effects of native defects in on the degradation of charge collection efficiency. A high-purity CVD diamond with thickness of 100 m was employed for the analysis, and as a result, a defect with activation energy of 0.27 eV which is involved in the degradation of CCE was detected.