Plasma facing surface composition during NSTX Li experiments

​Science Direct

Plasma facing surface composition during NSTX Li experiments

C.H.Skinnera, R. Sullenberger, B.E.Koel, M.A.Jaworski, H.W.Kugel

Published 16 January 2013

Lithium conditioned plasma facing surfaces have lowered recycling and enhanced plasma performance on many fusion devices. However, the nature of the plasma–lithium surface interaction has been obscured by the difficulty of in-tokamak surface analysis. We report laboratory studies of the chemical composition of lithium surfaces exposed to typical residual gases found in tokamaks. Solid lithium and a molybdenum alloy (TZM) coated with lithium have been examined using X-ray photoelectron spectroscopy, temperature programmed desorption, and Auger electron spectroscopy both in ultrahigh vacuum conditions and after exposure to trace gases. Lithium surfaces near room temperature were oxidized after exposure to 1–2 Langmuirs of oxygen or water vapor. The oxidation rate by carbon monoxide was four times less. Lithiated PFC surfaces in tokamaks will be oxidized in about 100 s depending on the tokamak vacuum conditions.


Request a call Back

For any questions or comments, please call 973-818-3428 or fill out the following form:

Contact Form 1

Send Request.