Surface modifications and deuterium retention in polycrystalline and single crystal tungsten as a function of particle flux and temperature

• Published in: Journal of nuclear materials Vol. 495; pp. 211 - 219
• Main Authors: Buzi, L., De Temmerman, G., Matveev, D., Reinhart, M., Schwarz-Selinger, T., Rasinski, M., Unterberg, B., Linsmeier, Ch, Van Oost, G.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-11-2017; Elsevier BV
• Subjects: Blistering; Desorption; Deuterium; Deuterium retention; Fluctuations; Ion flux; Microstructure; Plasmas (physics); Recrystallization; Retention; Single crystal; Single crystals; Spectroscopy; Temperature effects; Thermal desorption spectroscopy; Trapping; Tungsten; Blistering; Microstructure; Tungsten; Single crystal; Deuterium retention
• ISSN: 0022-3115; 1873-4820
• DOI: 10.1016/j.jnucmat.2017.08.026

The effects of particle flux and exposure temperature on surface modifications and deuterium (D) retention were systematically investigated on four different tungsten (W) microstructures. As-received, recrystallized, and single crystal W samples were exposed to D plasmas at surface temperatures of 530–1170 K. Two different ranges of D ion fluxes (1022 and 1024 D+m−2s−1) were used with the ion energy of 40 eV and particle fluence of 1026 D+m−2. Increasing the particle flux by two orders of magnitude caused blister formation and D retention even at temperatures above 700 K. The main effect of increasing the particle flux on total D retention was the shifting of temperature at which the retention was maximal towards higher temperatures. Diffusion-trapping simulations were used to fit the thermal desorption spectroscopy (TDS) release peaks of D, yielding one or two types of trapping sites with de-trapping energies around 2 eV.