Neutron diffraction monitoring of as-cast MgZnY during compression and tension

Harjo, S.; Aizawa, Kazuya; Gong, W.*; Kawasaki, Takuro

Materials Transactions, 61(5), p.828 - 832, 2020/04

https://doi.org/10.2320/matertrans.MT-MM2019003

Change in mechanical properties by high-cycle loading up to Gigacycle for 316L stainless steel

Naoe, Takashi; Harjo, S.; Kawasaki, Takuro; Xiong, Z.*; Futakawa, Masatoshi

JPS Conference Proceedings (Internet), 28, p.061009_1 - 061009_6, 2020/02

https://doi.org/10.7566/JPSCP.28.061009

At the J-PARC, a mercury target vessel made of 316L SS suffers proton and neutron radiation environment. The target vessel also suffers cyclic impact stress caused by the proton beam-induced pressure waves. The vessel suffers higher than 4.510 cyclic loading during the expected service life of 5000 h. We have investigated fatigue strength 316L SS up to gigacycle in the previous studies. The cyclic hardening and softening behavior were observed. In this study, to evaluate the cyclic hardening/softening behavior, the dislocation densities of specimens were measured using the neutron diffraction method at the MLF BL-19. The result showed that the dislocation density of a 316L SS was increased with increasing the number of loading cycles. By contrast, in the case of cold-rolled 316L SS, annihilation and re-accumulation of dislocation by cyclic loading were observed. In the workshop, result of neutron diffraction measurement will be introduced with the progress of fatigue test.

Neutron diffraction study on full-shape Japanese sword

Harjo, S.; Kawasaki, Takuro; Grazzi, F.*; Shinohara, Takenao; Tanaka, Manako*

Materialia, 7, p.100377_1 - 100377_9, 2019/09

https://doi.org/10.1016/j.mtla.2019.100377

Testing of time-of-flight neutron diffraction imaging using a high-resolution scintillator detector with wavelength-shifting fibers

Kawasaki, Takuro; Nakamura, Tatsuya; Gong, W.*; Oikawa, Kenichi

Physica B; Condensed Matter, 551, p.460 - 463, 2018/12

https://doi.org/10.1016/j.physb.2018.01.067

Deformation of CoCrFeNi high entropy alloy at large strain

Wang, B.*; He, H.*; Naeem, M.*; Lan, S.*; Harjo, S.; Kawasaki, Takuro; Nie, Y.*; Wang, X.-L.*; 7 of others*

Scripta Materialia, 155, p.54 - 57, 2018/10

https://doi.org/10.1016/j.scriptamat.2018.06.013

Non-destructive bond stress evaluation of bending and shear deformed reinforced concrete structure using neutron diffraction

Suzuki, Hiroshi; Kusunoki, Koichi*; Satake, Kosuke*; Kanematsu, Manabu*; Koyama, Taku*; Niwa, Akinobu*; Kabayama, Kenji*; Mukai, Tomohisa*; Kawasaki, Takuro; Harjo, S.

Hihakai Kensa, 67(4), p.180 - 186, 2018/04

https://doi.org/10.11396/jjsndi.67.180

The bond behavior between rebar and concrete under bending moment was investigated by measuring the stress distribution in the two-dimensionally distributed rebars embedded in the reinforced concrete (RC) beam using neutron diffraction. The stress distributions in both of the main rebar and the transverse stirrups embedded in concrete were successfully measured at the fixed measurement configuration without any sample rotations, by suggesting a simple measurement technique on the premise that the transverse restriction from the surrounding concrete to the main rebar is negligible. The bending and shear fracture behavior of the RC beam specimen was predicted by comparing changes in the stress distribution in the rebars measured by neutron diffraction with respect to the applied stress, with the macroscopic deformation measured by strain gauges fixed on the concrete surface. In this study, it was found that the neutron diffraction technique can be a useful technique to evaluate not only the anchorage performance but also the bending behavior of the RC beam.

Effect of hydrogenation conditions on the microstructure and mechanical properties of zirconium hydride

Muta, Hiroaki*; Nishikane, Ryoji*; Ando, Yusuke*; Matsunaga, Junji*; Sakamoto, Kan*; Harjo, S.; Kawasaki, Takuro; Oishi, Yuji*; Kurosaki, Ken*; Yamanaka, Shinsuke*

Journal of Nuclear Materials, 500, p.145 - 152, 2018/03

https://doi.org/10.1016/j.jnucmat.2017.12.027

Changes of dislocation density and dislocation arrangement during tensile deformation in lath martensitic steels

Harjo, S.; Kawasaki, Takuro; Morooka, Satoshi

Advanced Experimental Mechanics, 2, p.112 - 117, 2017/10

https://doi.org/10.11395/aem.2.0_112

Work hardening, dislocation structure, and load partitioning in lath-martensite determined by neutron diffraction line profile analysis

Harjo, S.; Kawasaki, Takuro; Tomota, Yo*; Gong, W.*; Aizawa, Kazuya; Tichy, G.*; Shi, Z.*; Ungar, T.*

Metallurgical and Materials Transactions A, 48(9), p.4080 - 4092, 2017/09

AA2017-0020.pdf:3.33MB

https://doi.org/10.1007/s11661-017-4172-0

Quantitative evaluation of texture and dislocations during annealing after hot deformation in austenitic steel using neutron diffraction

Tomota, Yo*; Sato, Shigeo*; Uchida, M.*; Xu, P. G.; Harjo, S.; Gong, W.; Kawasaki, Takuro

Materials Science Forum, 905, p.25 - 30, 2017/08

https://doi.org/10.4028/www.scientific.net/MSF.905.25