Mechanisms of gas precipitation in plasma-exposed tungsten

Conference · Tue May 01 04:00:00 EDT 2012

DOI:https://doi.org/10.1016/j.jnucmat.2013.01.222· OSTI ID:1054716

Kolasinski, R D; Cowgill, D F; Donovan, D C; Shimada, M

Precipitation in subsurface bubbles is a key process that governs how hydrogen isotopes migrate through and become trapped within plasma-exposed tungsten. We describe a continuum-scale model of hydrogen diffusion in plasma-exposed materials that includes the effects of precipitation. The model can account for bubble expansion via dislocation loop punching, using an accurate equation of state to determine the internal pressure. This information is used to predict amount of hydrogen trapped by bubbles, as well as the conditions where the bubbles become saturated. In an effort to validate the underlying assumptions, we compare our results with published positron annihilation and thermal desorption spectroscopy data, as well as our own measurements using the tritium plasma experiment (TPE).

• Research Organization: Idaho National Laboratory (INL)
• Sponsoring Organization: DOE - SC
• DOE Contract Number: AC07-05ID14517
• OSTI ID: 1054716
• Report Number(s): INL/CON-12-26061
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
bubbles and blisters
diffusion
hydrogen inventory
tungsten