Positron annihilation lifetime spectroscopy of FeCr and FeCrAl oxide dispersion strengthened (ODS) alloys

Ukai, Shigeharu; Hirade, Tetsuya; Okubo, Nariaki

Materials Characterization, 211, p.113813_1 - 113813_9, 2024/05

https://doi.org/10.1016/j.matchar.2024.113813

Positron annihilation lifetime spectroscopy (PALS) was performed to characterize the interface nanostructure between the oxide particles and the ferritic matrix for two types of the oxide dispersion-strengthened (ODS) alloys. The spectra were precisely decomposed with two trappings. For the shorter annihilation lifetime (179-194 ps), based on the advanced theoretical work by Kuramoto, it could be ascribed to positron trapping at vacancies and divacancies localized under the misfit dislocations. The longer annihilation lifetime (301-323 ps) could be Ar-filled gas bubbles precipitated at the oxide particle/matrix interfaces. The estimated number density of Ar-filled gas bubbles is the same order of the oxide particle number density measured by HRTEM.

Positron lifetime measurement on centrifuged BiPb intermetallic compound

Ono, Masao; Huang, X. S.*; Shibata, Yasuhiro*; Iguchi, Yusuke*; Sakai, Seiji; Maekawa, Masaki; Chen, Z. Q.*; Osakabe, Toyotaka; Kawasuso, Atsuo; Naramoto, Hiroshi*; et al.

Proceedings of 1st International Conference on Diffusion in Solids and Liquids (DSL 2005), p.531 - 533, 2005/07

Recently, we formed atomic-scale graded structures in some miscible alloys and observed the decomposition in BiPb intermetallic compound by sedimentation of atoms under strong gravitational field. In this study, we measured positron lifetime of centrifuged BiPb, to which the composition change was very small as it was treated at low temperature. It was found that the positron lifetime became longer than that of starting state. This indicated that the point defects (vacancy or divacancy) increased in the sample by centrifugal treatment. We are now investigating the relationship between increase in point defects and sedimentation of atoms.

Positron annihilation study on neutron irradiated Si

S.Zhu*; A.Li*; S.Zheng*; H.Huang*; D.Li*; Iwata, Tadao

Chin. J. Nucl. Phys., 14(2), p.166 - 168, 1992/00

no abstracts in English

Temperature dependency in positronium imaging; Measurement using VRAIN

Takyu, Sodai*; Hirade, Tetsuya; Matsumoto, Kenichiro*; Nishikido, Fumihiko*; Akamatsu, Go*; Tashima, Hideaki*; Takahashi, Miwako*; Yamaya, Taiga*

no journal, ,