Deuterium retention in MeV ion-irradiated beryllium

• Published in: Journal of nuclear materials Vol. 555; no. C; p. 153139
• Main Authors: Založnik, Anže, Doerner, Russell P., Schwarz-Selinger, Thomas, Miyamoto, Mitsutaka, Brezinsek, Sebastijan
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.11.2021; Elsevier BV; Elsevier
• Subjects: Beryllium; Crystal lattices; Deuterium; Deuterium plasma; Hydrogen isotopes; Irradiation; Neutrons; Nuclear reactions; Oxygen ions; Radiation; Radiation damage; Retention; Spectroscopy; Thermal desorption spectroscopy; Transmission electron microscopy; Tungsten
• ISSN: 0022-3115; 1873-4820
• DOI: 10.1016/j.jnucmat.2021.153139

Beryllium, as the material of choice for the ITER first wall, will be subject to high energy neutrons during the operation of the fusion device. Such irradiation will create displacement damage in the crystal lattice, which is known to influence hydrogen isotope retention, e.g. in iron and tungsten. In our study, we irradiated beryllium samples with high-energy oxygen ions up to various dpa levels (0.01 dpa, 0.1 dpa, and 1 dpa) and subsequently exposed the samples to deuterium plasma at 370 K and 573 K. The amount of retained deuterium was measured by thermal desorption spectroscopy and nuclear reaction analysis and was found to decrease by about 18% in the samples damaged up to 0.1 dpa compared to the undamaged ones. Further damaging up to 1 dpa did not show any additional effects on deuterium retention. Transmission electron microscopy was used to check for the existence of bubbles after plasma exposure.