Nishida, Satoru*; Nishino, Soichiro*; Sekine, Masahiko*; Oka, Yuki*; Harjo, S.; Kawasaki, Takuro; Suzuki, Hiroshi; Morii, Yukio*; Ishii, Yoshinobu*
Materials Transactions, 62(5), p.667 - 674, 2021/05
Xu, P. G.; Harjo, S.; Ito, Takayoshi*; Morii, Yukio*; Gong, W.; Suzuki, Hiroshi; Akita, Koichi; Suzuki, Tetsuya*; Tomota, Yo; Lutterotti, L.*
JPS Conference Proceedings (Internet), 8, p.031022_1 - 031022_6, 2015/09
Xu, P. G.; Hoshikawa, Akinori*; Hayashi, Makoto*; Akita, Koichi; Morii, Yukio*; Ishigaki, Toru*
Nihon Zairyo Gakkai Dai-48-Kai X Sen Zairyo Kyodo Ni Kansuru Shimpojiumu Koen Rombunshu, p.7 - 9, 2014/07
Suzuki, Hiroshi; Katsuyama, Jinya; Morii, Yukio*
Journal of Solid Mechanics and Materials Engineering (Internet), 6(6), p.574 - 583, 2012/06
Residual stress distributions of 35 mm thick dissimilar butt-weld between A533B ferritic steel and Type 304 austenitic stainless steel (304SS) with Ni alloy welds and similar metal butt-weld of 304SS were measured using neutron diffraction. Effects of differences in thermal expansion coefficients (CTEs) and material strengths on the weld residual stress distributions are discussed by comparison of the residual stress distributions between the similar and dissimilar metal butt-welds. Residual stresses in the similar metal butt-weld exhibited typical distributions found in a thick butt-weld and they were distributed symmetrically on either side of the weld line. Meanwhile, asymmetric residual stress distributions were observed near the root of the dissimilar metal butt-weld, which was caused by differences in CTEs and yield strengths between parent and weld metals. Transverse residual stress distribution of the dissimilar metal butt-weld was similar trend to that of the similar metal butt-weld, since effects of differences in CTEs are negligible, while magnitude of the transverse residual stress near the root depended on the yield strengths of each metal. In contrast, the normal and longitudinal residual stresses in the dissimilar metal butt-weld distributed asymmetrically on either side of weld line due to influence of differences in CTEs.
Suzuki, Hiroshi; Katsuyama, Jinya; Tobita, Toru; Morii, Yukio*
Yosetsu Gakkai Rombunshu (Internet), 29(4), p.294 - 304, 2011/12
The RESA-1 neutron engineering diffractometer in the JRR-3 (Japan Research Reactor No.3) at the Japan Atomic Energy Agency, which is used for stress measurements, was upgraded to realize residual stress measurements of large scaled mechanical components. A series of residual stress measurements was made to obtain through-thickness residual stress distributions in a Type 304 stainless steel butt-welded pipe of 500A-sch.80 using the upgraded RESA-1 diffractometer. We evaluated effects of crack propagation such as stress corrosion cracking (SCC) and a part-circumference repair weld on the residual stress distributions induced by girth welding. Measured residual stress distributions near original girth weld revealed good agreement with typical results shown in some previous works using finite element method, deep hole drilling as well as neutron diffraction. After introducing a mock crack with 10 mm depth in heat affected zone on the inside wall of the pipe by electro discharge method, the axial residual stresses were found to be released in the part of the mock crack. However, changes in the through-wall bending stress component and the self-equilibrated stress component were negligible and hence the axial residual stress distribution in the ligament was remained in the original residual stresses near girth weld without the mock crack. Furthermore, changes in hoop and radial residual stress were also small. The residual stress distributions after a part repair welding on outer circumference of girth weld were significantly different from residual stress distributions near the original girth weld. Membrane residual stress was increased in the axial direction since the bending moment near the heat affected zone was changed due to repair weld. Throughout above studies, we evidenced that the neutron diffraction technique is useful and powerful tool for measuring residual stress distributions in large as well as thick mechanical components.
Suzuki, Hiroshi; Katsuyama, Jinya; Morii, Yukio*
Proceedings of International Conference on Advanced Technology in Experimental Mechanics 2011 (ATEM '11) (CD-ROM), 9 Pages, 2011/09
Residual stress distributions of 35 mm thick dissimilar butt-weld between A533B ferritic steel and Type 304 austenitic stainless steel (304SS) with Ni alloy welds and similar metal butt-weld of 304SS were measured using neutron diffraction. Effects of differences in thermal expansion coefficients and material strengths on the weld residual stress distributions are discussed by comparison of the residual stress distributions between the similar and dissimilar metal butt-welds. Residual stresses in the similar metal butt-weld exhibited typical distributions of a thick butt-weld and they were distributed symmetrically on either side of the weld line. Meanwhile, asymmetric residual stress distributions were observed near the root region of the dissimilar metal butt-weld, which was caused by differences in thermal expansion coefficients (CTEs) and yield strengths between parent and weld metals. Transverse residual stress distribution of the dissimilar metal butt-weld was similar to that of the similar butt-weld, since effects of differences in CTEs are negligible. Magnitude of the transverse residual stress near the root region depended on the yield strengths of each metal. The normal and longitudinal residual stresses in the dissimilar metal butt-weld distributed asymmetrically on either side of weld line due to the effects of differences in CTEs.
Yoshii, Kenji; Hiramitsu, Yusuke*; Okajima, Yuka*; Yoneda, Yasuhiro; Nishihata, Yasuo; Mizuki, Junichiro; Nakamura, Akio; Shimojo, Yutaka; Ishii, Yoshinobu*; Morii, Yukio; et al.
Materials Research Bulletin, 45(11), p.1574 - 1580, 2010/10
Magnetic and dielectric properties of perovskite manganites RSrMnO (R = Gd, Tb and Dy) have been investigated. DC and AC magnetic measurements showed short-range glassy magnetic ordering at Tg about 40 K. Such ordering was observed by neutron diffraction and is ascribable to the size mismatch of R and Sr settled randomly at the same crystallographic site. Dielectric constants for each material were about 1000-10000 between about 50 K and 300 K and showed broad maximums above Tg. Dielectric dispersion showed poor coherency of the motion of polar regions, plausibly because of the size-mismatch effect; both the magnetic and dielectric properties of this system are governed by the randomness at the R/Sr site. The tan and EXAFS data suggest that the dielectric response is rooted in a transfer of the Mn-3d electrons.
Oyama, Yukio; Ikeda, Yujiro; Arai, Masatoshi; Morii, Yukio
Nihon Genshiryoku Gakkai-Shi ATOMO, 51(1), p.14 - 19, 2009/01
The beam commissioning of the J-PARC facilities of which the construction was started in 2001 is now progressed toward completion at the end of JFY2008. Of the J-PARC facilities, especially the pulsed neutron source with the world highest performance is able to open a new era of neutron application research. In this article, the outline of J-PARC, the pulsed neutron source which will start the user operation on December 2008, and their neutron instruments which is under construction are introduced. The neutron research is one of the important applications of quantum beam technology and expected to expand to broad research area such as bio-science, materials science, industrial use, etc. by start of J-PARC utilization. The latest achievement of neutron research mostly conducted at the JRR-3 research reactor in operation and future prospect are overviewed.
Okayasu, Satoru; Katagiri, Masaki; Hojo, Kiichi; Morii, Yukio; Miki, Shigenobu*; Shimakage, Hisashi*; Wang, Z.*; Ishida, Takekazu*
Physica C, 468(15-20), p.1998 - 2000, 2008/09
We have been investigating for neutron detection with the MgB transition edge sensor (TES). For the purpose, we have been developing a low noise measurement system for neutron detection. To confirm the usefulness of our detecting system, alpha-ray detection from an Am source was achieved. To improve the sensitivity, short meander samples with 35 m length and 1 m width is used. Samples are fabricated by the Kansai group. Superconducting transition temperature Tc is 23.3 K. The transition width is sharp enough less than 1 K. The detection was achieved under a constant current condition, and the resistivity changes at the sample due to the alpha-ray irradiation were detected. The bias current is 6 A.
Hiramitsu, Yusuke*; Yoshii, Kenji; Yoneda, Yasuhiro; Mizuki, Junichiro; Nakamura, Akio; Shimojo, Yutaka; Ishii, Yoshinobu*; Morii, Yukio; Ikeda, Naoshi*
Japanese Journal of Applied Physics, Part 1, 46(10B), p.7171 - 7174, 2007/10
Magnetic and dielectric properties of a perivskite manganite TbCaMnO were investigated. Magnetic measurements showed three characteristic temperatures, originating from charge ordering (300 K), antiferromagnetic ordering (120 K) and a transition to a glassy state (50 K). The coexistence of the charge and antiferromagnetic ordering was consistent with the result of powder neutron diffraction. AC dielectric measurements showed large dielectric constants of about 5000 at around room temperature. A temperature dependence of the dielectric constant changed just below the charge-ordering temperature. From the analysis of tan;, the activation energy for a domain-boundary motion was calculated to be about 0.09 eV. These results strongly suggest that the dielectric properties of this material are governed by the ordering and transfer of the Mn-3d charges.
Suzuki, Hiroshi; Waku, Yoshiharu*; Nakagawa, Narihito*; Akita, Koichi*; Moriai, Atsushi; Morii, Yukio
Journal of Neutron Research, 15(2), p.113 - 120, 2007/06
The residual stress in only YAG phase was measured on the surface of the AlO-YAlO(YAG) eutectic composite(AlO/YAG MGC) using the low energy synchrotron X-rays. The residual stresses in plane stress condition were significantly different between top and side surfaces of the specimen. Therefore, an anisotropic triaxial residual stress probably exists within the MGC. The residual stress within the MGC was also measured using a neutron diffraction. The residual stress in the YAG phase rose from compression in the solidification direction to tension in perpendicular direction. The residual stress in the AlO phase was anisotropic compression and there was no tension in all directions. This anisotropic residual stress could be explained by the crystallographic anisotropy of thermal expansion in the AlO phase. However, both phase stresses were not balanced, so that it is expected that there would be the stress distribution in MGC sample used in this study.
Yoshii, Kenji; Mizumaki, Masaichiro*; Kato, Kazuo*; Uruga, Tomoya*; Abe, Hideki*; Nakamura, Akio; Shimojo, Yutaka; Ishii, Yoshinobu; Morii, Yukio
Journal of Solid State Chemistry, 180(1), p.377 - 381, 2007/01
no abstracts in English
Harjo, S.; Moriai, Atsushi; Torii, Shuki; Suzuki, Hiroshi; Suzuya, Kentaro; Morii, Yukio; Arai, Masatoshi; Tomota, Yo*; Akita, Koichi*; Akiniwa, Yoshiaki*
Materials Science Forum, 524-525, p.199 - 204, 2006/00
An engineering diffractometer designed to solve many problems in materials science and engineering including investigations of stresses and crystallographic structures within engineering components is now being developed at J-PARC project. This instrument views a decoupled-poisoned liquid H moderator, and the primary and the secondary flight paths are 40 m and 2.0 m, respectively, for 90 degree scattering detector banks. The optimization of this instrument has been performed with a Monte Carlo simulation, and an appropriate resolution of less than 0.2 % in d/d has been confirmed. A prototyped radial collimator to define a gauge width of 1 mm has been designed and manufactured. From performance tests conducted at the neutron diffractometer for residual stress analysis RESA, the normal distribution with a full width at half maximum of 1.0 mm was obtained in a good agreement with the simulation.
Morii, Yukio; Imase, Hajime*
Hoshasen To Sangyo, (107), p.52 - 55, 2005/09
no abstracts in English
Suzuki, Hiroshi; Holden, T. M.*; Moriai, Atsushi; Minakawa, Nobuaki*; Morii, Yukio
Zairyo, 54(7), p.685 - 691, 2005/07
no abstracts in English
Suzuki, Hiroshi; Moriai, Atsushi; Minakawa, Nobuaki*; Morii, Yukio
Zairyo, 54(3), p.339 - 345, 2005/03
In a conventional method of a neutron stress measurement, it is required to know the stress-free lattice constant accurately. A new stress measurement method, which does not need the lattice constant of the strain-free material, was applied to evaluate the residual stress distributions in welded sample. The lattice constant distribution which was measured by using our proposed method showed an increase as close to the weld zone, and the absolute value of the lattice constant almost agreed with the lattice constant which was measured using coupons cut from welded sample. Therefore, it is possible to predict the lattice constant by using our proposed method. The residual stress distributions were evaluated by using conventional method and our proposed method. As a result, the residual stress distributions decided by our proposed method almost agreed with those measured by conventional method. This proposed method can be applied to determination of the residual stress states in the samples with the complex residual stress states.
Suzuki, Hiroshi; Minakawa, Nobuaki*; Moriai, Atsushi; Hataya, Mitsuhiko*; Morii, Yukio
Materials Science Forum, 490-491, p.245 - 250, 2005/00
In the conventional stress measurement method using neutron diffraction, it is required to measure the lattice strains of the same diffraction family in all three orthogonal directions. However, it is possibly difficult to measure the lattice strains of the same diffraction family in all three directions on the textured material, and also the lattice strains in three directions may not be measured in some reasons such as the size and the shape of the sample, etc. Moreover, in conventional method, it is required to know the accurate stress free lattice spacing d, so that the stress measurement accuracy depends on the accuracy of d of powder or annealed samples. In this study, we proposed new stress measurement method which can determine the residual stress states by measuring the lattice strains in two or three orthogonal directions even if the measured diffraction families were different in all three directions. Furthermore, stress measurement method which can determine the internal residual stresses without using measured d was also proposed.
Yoshii, Kenji; Nakamura, Akio; Mizumaki, Masaichiro*; Tanida, Hajime*; Kawamura, Naomi*; Abe, Hideki*; Ishii, Yoshinobu; Shimojo, Yutaka; Morii, Yukio
Journal of Magnetism and Magnetic Materials, 272-276(Suppl.), p.e609 - e611, 2004/05
no abstracts in English
Minakawa, Nobuaki; Moriai, Atsushi; Morii, Yukio
Nihon Zairyo Gakkai Dai-38-Kai X Sen Zairyo Kyodo Ni Kansuru Shimpojiumu Koen Rombunshu, p.202 - 205, 2002/09
no abstracts in English