observation of recrystallization of aluminum single crystals using synchrotron radiation monochromatic X-rays

Shiro, Ayumi*; Shobu, Takahisa; Okada, Tatsuya*

Zairyo, 71(4), p.354 - 360, 2022/04

https://doi.org/10.2472/jsms.71.354

Recrystallization process of an aluminum (Al) single crystal was observed in situ using synchrotron X-rays. Al single-crystalline samples were deformed in tension along a 111 direction to a strain of 8%, and were subsequently annealed at 753 K. The changes in the shape and intensity of diffraction spots were analyzed using a two-dimensional detector. A diffraction spot from the deformation matrix had three peaks which reflected a sub-grained microstructure of the sample. The observation during annealing unveiled the appearance of diffraction spots from a recrystallized grain at 330.8 s. As the diffraction spots from the recrystallized grain became larger, the diffraction spots from the deformation matrix gradually disappeared. The application of the X-ray topography method revealed the crystal orientation variation in a recrystallized grain in order of 0.001 degree.

synchrotron radiation observation of deformation and annealing processes of aluminum single crystal

Shiro, Ayumi*; Okada, Tatsuya*; Shobu, Takahisa

Mechanical Engineering Journal (Internet), 8(6), p.21-00106_1 - 21-00106_8, 2021/12

https://doi.org/10.1299/mej.21-00106

The objective of the present study was to carry out observations of deformation and annealing processes of aluminum single crystals using a synchrotron radiation X-rays at SPring-8. Al single-crystalline samples having a 111 orientation parallel to the longitudinal direction were grown by a Bridgman method. The samples were deformed in tension to a nominal strain of 0.08 at room temperature using an in-line tensioning apparatus. Post-deformation annealing at 480 C was subsequently carried out in the same apparatus. A two-dimensional detector was used to detect multiple diffracted beams from the sample during the deformation and annealing processes. The volume irradiated by the X-ray beam was found to be composed of three regions having a small orientation difference, which was attributable to sub-grained microstructures of the sample. Detailed analyses of a diffraction spot intensity showed that the sub-grained microstructures were surpassed by dislocated microstructures with the increase in the tensile strain. During the post-deformation annealing, diffraction spots from a recrystallized grain first appeared at 180 s after the temperature reached 480 C. Coexistence of diffraction spots from the deformation matrix and recrystallized grain lasted only for about 22 s in the irradiated volume. The migration rate of the boundary between the deformation matrix and recrystallized grain was estimated to be of the order of several micrometers/s.

Element effects of Mn and Ge on the tuning of mechanical properties of high-entropy alloys

Lam, T.-N.*; Tsai, C.-W.*; Chen, B.-K.*; Lai, B.-H.*; Liu, H.-C*; Kawasaki, Takuro; Harjo, S.; Lin, B.-H.*; Huang, E.-W.*

Metallurgical and Materials Transactions A, 51(10), p.5023 - 5028, 2020/10

https://doi.org/10.1007/s11661-020-05932-9

Application of neutron, 2; Materials evaluation using the Japan Proton Accelerator Research Complex (J-PARC)

Morooka, Satoshi

Hozengaku, 19(1), p.29 - 34, 2020/04

no abstracts in English

Martensite phase stress and the strengthening mechanism in TRIP steel by neutron diffraction

Harjo, S.; Tsuchida, Noriyuki*; Abe, Jun*; Gong, W.*

Scientific Reports (Internet), 7(1), p.15149_1 - 15149_11, 2017/11

AA2017-0453.pdf:3.62MB

https://doi.org/10.1038/s41598-017-15252-5

Reverse austenite transformation behavior in a tempered martensite low-alloy steel studied using neutron diffraction

Tomota, Yo*; Gong, W.*; Harjo, S.; Shinozaki, Tomoya*

Scripta Materialia, 133, p.79 - 82, 2017/05

AA2017-0349.pdf:2.43MB

https://doi.org/10.1016/j.scriptamat.2017.02.017

In-situ measurement of transitional stress in welds metal of steel using synchrotron radiation

Tsuji, Akihiro*; Zhang, S.*; Hashimoto, Tadafumi*; Okano, Shigetaka*; Shobu, Takahisa; Mochizuki, Masahito*

Zairyo, 65(9), p.665 - 671, 2016/09

https://doi.org/10.2472/jsms.65.665

It is necessary to control weld residual stress which has negative influence on fracture strengths. In structural steel welds, complex residual stress fields are formed due to phase transformation that occur according to the thermal cycles. In this study, in-situ evaluation of phase transformation and transitional stress simultaneously during welding is discussed. In the test using SM490A, after cooling process, stress evaluated by this system showed good agreement with that evaluated by lab X-ray. During austenite to ferrite transformation in weld metal, tensile stress occurred in austenite and compressive stress occurred in ferrite. Moreover, stress concentration was occurred in ferrite phase immediately after the start of phase transformation. Also, stress concentration was occurred in austenite phase just before the end of phase transformation.

Domain boundaries in the GaAs(001)-24 surface

Takahashi, Masamitsu; Yoneda, Yasuhiro; Yamamoto, Naomasa*; Mizuki, Junichiro

Physical Review B, 68(8), p.085321_1 - 085321_5, 2003/08

https://doi.org/10.1103/PhysRevB.68.085321

The , and phases of the GaAs(001)-24 surface have been investigated by surface X-ray diffraction in an As flux and at temperatures ranging from 480C to 610C. It has been found that the fractional-order peaks originating from the fourfold symmetry show shift in the [110] direction as well as significant broadening of the peaks in the and phases. The direction of the peak shift is characteristic in each phase. This behavior is explained by the formation of the antiphase domain boundaries. The atomic structure of the domain boundaries is discussed.

IEA Workshop on In-Situ Measurements of Electrical Properties of Irradiated Ceramics

Ono, Hideo

Nihon Genshiryoku Gakkai-Shi, 32(11), p.1099 - 1100, 1990/11

no abstracts in English

In-situ measurement of strain distribution in lap joint materials under high temperature and tensile stress using synchrotron radiation

Shobu, Takahisa; Shiro, Ayumi; Muramatsu, Toshiharu; Yamada, Tomonori; Naganuma, Masayuki; Ozawa, Takayuki

no journal, , 

no abstracts in English