Gradient residual strain measurement procedure in surface impacted railway steel axles by using neutron scattering

Zhou, L.*; Zhang, H.*; Qin, T. Y.*; Hu, F. F.*; Xu, P. G.; Ao, N.*; Su, Y. H.; He, L. H.*; Li, X. H.*; Zhang, J. R.*; et al.

Metallurgical and Materials Transactions A, 11 Pages, 2024/00

https://doi.org/10.1007/s11661-024-07352-5

Influence of pulse duration on mechanical properties and dislocation density of dry laser peened aluminum alloy using ultrashort pulsed laser-driven shock wave

Yoshida, Masayuki*; Nishihata, Itsuki*; Matsuda, Tomoki*; Ito, Yusuke*; Sugita, Naohiko*; Shiro, Ayumi*; Shobu, Takahisa; Arakawa, Kazuto*; Hirose, Akio*; Sano, Tomokazu*

Journal of Applied Physics, 132(7), p.075101_1 - 075101_9, 2022/08

https://doi.org/10.1063/5.0083511

Effects of residual stress on hydrogen embrittlement of a stretch-formed tempered martensitic steel sheet

Nishimura, Hayato*; Hojo, Tomohiko*; Ajita, Saya*; Shibayama, Yuki*; Koyama, Motomichi*; Saito, Hiroyuki*; Shiro, Ayumi*; Yasuda, Ryo*; Shobu, Takahisa; Akiyama, Eiji*

Tetsu To Hagane, 107(9), p.760 - 768, 2021/09

https://doi.org/10.2355/tetsutohagane.TETSU-2021-055

no abstracts in English

Application of neutron, 1; Neutron stress measurement in the research reactor JRR-3

Suzuki, Hiroshi

Hozengaku, 19(1), p.24 - 28, 2020/04

no abstracts in English

Practical measurement of residual stresses using contour method

Ikushima, Kazuki*; Shibahara, Masakazu*; Kawajiri, Yoshitaka*; Okimi, Yui*; Uchida, Tomoki*; Akita, Koichi*; Suzuki, Hiroshi; Morooka, Satoshi

Nihon Senpaku Kaiyo Kogakkai Rombunshu, (30), p.123 - 130, 2019/12

https://doi.org/10.2534/jjasnaoe.30.123

In this research, the contour method was applied to measure the residual stress distribution of a bead-on-plate specimen. The measured residual stress distribution was compared with those measured by neutron diffraction method and calculated by thermal elastic plastic finite element analysis. As a result, it was found that the residual stress distribution obtained by these three methods are in good agreement. In addition, the equilibrium of reaction force on cut plane was considered in the contour method to measure residual stresses in asymmetric cutting which is assumed in the measurement of real structures. The proposed method was applied to the measurement of the residual stress in the multi-pass welded joint. The measured results indicated that the proposed method can measure the residual stress distribution in multi-pass welded joint in asymmetric test specimen.

Evaluation of residual stress relaxation in a rolled joint by neutron diffraction

Hayashi, Makoto*; Root, J. H.*; Rogge, R. B.*; Xu, P. G.

Quantum Beam Science (Internet), 2(4), p.21_1 - 21_16, 2018/12

AA2018-0259.pdf:2.23MB

https://doi.org/10.3390/qubs2040021

Numerical analysis of residual stress distribution on peening process

Ikushima, Kazuki*; Shibahara, Masakazu*; Akita, Koichi; Suzuki, Hiroshi; Morooka, Satoshi; Nishikawa, Satoru*; Furukawa, Takashi*

Welding in the World, 61(3), p.517 - 527, 2017/05

http://doi.org/10.1007/s40194-017-0430-4

In this study, first, an analysis method to predict the behaviour of residual stress distribution on shot peening process was proposed. In the proposed method, the load distribution on the collision of shots was modelled, and it was integrated with the dynamic analysis method based on the idealized explicit FEM (IEFEM). The accuracy of the proposed analysis system was confirmed by comparing the stress distribution on the collision of a single shot with the results analyzed by ABAQUS. The thermal elastic plastic analysis method using IEFEM was applied to the analysis of residual stress distribution of multi-pass welded pipe joint. The calculated residual stress distribution was compared with the measured residual stress distribution using X-ray diffraction (XRD). As a result, it was shown that the both welding residual distribution agree well with each other. Considering the calculated welding residual stress distribution, the modification of stress distribution due to shot peening was predicted by the proposed analysis system. As a result, the similar stress distribution with measurement by XRD was obtained in case that a large number of collisions are considered.

Internal stress distribution for generating closure domains in laser-irradiated Fe-3%Si(110) steels

Iwata, Keiji*; Imafuku, Muneyuki*; Suzuki, Kanki*; Shobu, Takahisa; Orihara, Hideto*; Sakai, Yusuke*; Akita, Koichi; Oya, Shinichi*; Ishiyama, Kazushi*

Journal of Applied Physics, 117(17), p.17A910_1 - 17A910_4, 2015/03

https://doi.org/10.1063/1.4916183

Internal stress distribution for generating closure domains occurring in laser-irradiated Fe-3%Si(110) steels was investigated using high-energy X-ray analysis and domain theory based on the variational principle. The measured triaxial stresses inside the specimen were compressive and the stress in the rolling direction became more dominant than stresses in the other directions. The calculations based on the variational principle of magnetic energy for closure domains showed that the measured triaxial stresses made the closure domains more stable than the basic domain without closure domains. The experimental and calculation results reveal that the laser-introduced internal stresses result in the occurrence of the closure domains.

Cause investigation and repair of breakage of catalyst dust filter on mock-up model test facility with a full-scale reaction tube for HTTR hydrogen production system (Contract research)

Morisaki, Norihiro; Hayashi, Koji; Inagaki, Yoshiyuki; Kato, Michio; Fujisaki, Katsuo*; Maeda, Yukimasa; Mizuno, Sadao*

JAERI-Tech 2005-009, 37 Pages, 2005/03

JAERI-Tech-2005-009.pdf:14.33MB

The breakage of the catalyst dust filter was found at the nozzle flange, which was welded onto the end plate of the filter, by the bubbling test using nitrogen gas of the mock-up model test facility. We investigated the cause of breakage and devised a repairing method. The cause of the breakage was the stress corrosion cracking (SCC) generated from the inside of the filter. The filter was repaired based on the following countermeasures such as reduction of condensed water in the filter, tensile stress and sensitization at welding joints. Furthermore, the inspection was carried out to investigate the structural integrity of the welding joints in the test facility of which structure, material and operating condition were similar to the filter. As the results, it was confirmed that the structural integrity was maintained.

Report of Examination of the Samples from Primary Loop Recirculation Piping (O1-PLR) at Onagawa Nuclear Power Station Unit-1 (Contract research)

The Working Team for Examination Operation of Samples from Primary Loop Recirculation Piping at Onag

JAERI-Tech 2004-003, 74 Pages, 2004/02

JAERI-Tech-2004-003.pdf:30.08MB

The present examination has been performed with the objective to provide technical basis for identifying causes of cracking through the examination of the samples, which was conducted at the post irradiation examinations facilities of JAERI, taken from the cracked region of the recirculation pipe at the Onagawa Nuclear Power Station Unit-1. The following findings were obtained from this examination result. (1) Cracks were observed near the weld region of inner surface of the pipe and depth of the crack was about 5 to 7mm. (2) Intergranular crackings were observed in the almost whole fracture surface. Partially transgranular cracking was observed at the surface layer with the depth of about 100m. Microstructure formed by cold work and increase of hardness were observed in these surface layers. Cracks initiated near the region where hardness value was the highest. Based on the examination results described above concerning presence of tensile residual stress by welding and relatively high dissolved oxygen contents in core coolant and so on, it is concluded that these cracks were initiated in the cold work layer of inner surface by stress corrosion cracking (SCC) and propagated along the grain boundaries.