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.

Study on shot peened residual stress distribution under cyclic loading by numerical analysis

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

Yosetsu Gakkai Rombunshu (Internet), 35(2), p.75s - 79s, 2017/06

http://www.jweld.jp/quarterly/v35/visual/35_75s.pdf

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.

In-situ neutron stress measurements on dissimilar weld joint in thermal cycles

Akita, Koichi; Nishikawa, Satoru*; Shibahara, Masakazu*; Ikushima, Kazuki*; Suzuki, Hiroshi; Moriai, Atsushi; Harjo, S.; Aizawa, Kazuya

no journal, , 

To clarify the residual stress relaxation process in a dissimilar weld joint, the in-situ neutron stress measurements during thermal cycles were conducted using TAKUMI in J-PARC. The materials used for the base plates were a Ni-alloy (NCF600) and a stainless steel (SUS316L). The temperature range was from RT to 593 K. From the experimental results, it was found that residual stress of the Ni-alloy increased, while the residual stress of the stainless steel decreased, in the heating process. And, the residual stress of the Ni-alloy reaches the yield strength of the material in the heating process. It results in the redistribution of the residual stress, and therefore the residual stress relaxation occurs.

Evaluation of the sustainability of compressive residual stress by introduced a stress improvement method, 2; Residual stress change of welded joint with shot peening by thermal cycle and stress loading

Nishikawa, Satoru*; Furukawa, Takashi*; Akita, Koichi; Suzuki, Hiroshi; Morooka, Satoshi; Harjo, S.; Shibahara, Masakazu*; Ikushima, Kazuki*; Kitani, Yuji*; Yamada, Yusuke*

no journal, , 

no abstracts in English

Study of behavior to relieve residual stress at the time of the shot peening

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

no journal, , 

no abstracts in English

Evaluation of residual stress behaviors of reactor coolant pipe in whole process from welding and peening to operating condition; Neutron stress measurement and numerical analysis

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

no journal, , 

no abstracts in English

Residual stress measurements of Ni-based alloy-sus316l dissimilar weld joint under thermal cycle by neutron diffraction

Akita, Koichi; Moriai, Atsushi; Suzuki, Hiroshi; Harjo, S.; Nishikawa, Satoru*; Shibahara, Masakazu*; Ikushima, Kazuki*

no journal, , 

Internal residual stresses of a dissimilar weld joint under cyclic thermal aging were measured using neutron diffraction technique and the residual stress relaxation process was investigated.

Finite element analysis of residual stress distribution on shot peening

Ikushima, Kazuki*; Kitamura, Yoshisato*; Kitani, Yuji*; Shibahara, Masakazu*; Nishikawa, Satoru*; Akita, Koichi

no journal, , 

no abstracts in English