Sputtering of graphite walls in the TM-G tokamak

Journal Article · Sun Mar 01 04:00:00 EST 1987 · Sov. J. Plasma Phys. (Engl. Transl.); (United States)

OSTI ID:6230888

Dremin, M M; Pavlov, Y D; Petrov, D P; Solntsev, A M; Stefanovskii, A M; Terebkov, A L

Various effects which occur in the interaction of hydrogen atoms and ions with the wall material have been measured in the TM-G tokamak, with an all-graphite discharge chamber. Experiments were carried out at a wall temperature of 350/sup 0/ C. In the time interval between discharges, intense outgassing from the graphite was observed. It thus became possible to measure the characteristics of the chemical sputtering of the graphite, the bulk diffusion of hydrogen in the walls, and the number of atoms implanted in the graphite during the discharge. The amount of hydrogen recycling, the impact-desorption cross section, and the integral sputtering coefficient of the graphite during the discharge were also measured. The integral sputtering coefficient was found to be 2--3%, or two or three times the calculated physical-sputtering coefficient and tens of times the chemical-sputtering coefficient. An expression is offered for the chemical sputtering. This expression gives a satisfactory description of the temperature dependence of the chemical sputtering of the graphite.

• Research Organization: I.V. Kurchatov Institute of Atomic Energy, Moscow
• OSTI ID: 6230888
• Journal Information: Sov. J. Plasma Phys. (Engl. Transl.); (United States), Journal Name: Sov. J. Plasma Phys. (Engl. Transl.); (United States) Vol. 13:3; ISSN SJPPD
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700103* -- Fusion Energy-- Plasma Research-- Kinetics
CARBON
CHARGE EXCHANGE
CLOSED PLASMA DEVICES
DIFFUSION
ELECTRON ATTACHMENT
ELEMENTAL MINERALS
ELEMENTS
GRAPHITE
LIMITERS
MINERALS
NONMETALS
PLASMA DIAGNOSTICS
RECOMBINATION
SPECTROSCOPY
SPUTTERING
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
WALL EFFECTS