Luch Research & Production Association, Podolsk, Russia:

A. A. Urusov, Head of Laboratory
S. V. Chuvikov, Research Fellow
K. K. Polunin, Research Fellow

National Research Nuclear University MEPhI, Moscow, Russia:
A. V. Tenishev, Associate Professor, Candidate of Technical Sciences, e-mail: avt@onil709.ru

This paper looks at the effect of ion beam radiation on a dysprosium hafnate material (Dy₂O₃ – HfO₂) that can potentially serve as a neutron absorber. The study was based on a serial radiography with helium and nickel ions at the temperatures of 350 and 550 ^oС to the doses of 20, 100, 200 and 300 dpa. Using scanning and transmission electron microscopy, the authors examined the microstructure of specimens both in their initial state and after exposure. Electron probe microanalysis helped determine the concentration of the elements in the specimens. The paper demonstrates that exposure of dysprosium hafnate to a damaging dose of 20 dpa does not lead to any visible structural changes. When the dose exceeded 100 dpa, the authors observed changes in the surface morphology of the specimens and a gradual closing-up of process-related pores. Calculation results indicate that the swelling of the dysprosium hafnate specimens does not exceed 0.1% at the maximum accumulated radiation of 200 to 300 dpa.
The authors would like to thank P. S. Dzhumaev, M. S. Staltsov and O. V. Emelianova for their support with scanning electron microscopy and electron probe microanalysis; D. P. Shornikov for his support with systematization and processing of experimental data.

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