The first wall and the vessel of the Reversed Field Pinch RFX has been in situ coated with a B/C:H film by glow discharge cleaning with a mixture of 12.5% of trimethylboron ((CH3)(3)B) in He. The film has been analysed and the effects on the plasma discharges of the boronized wall are reported for a plasma current of 520 kA. The main effects on the plasma are a reduction in the oxygen content by a factor of 5 to 10 and a decrease in the carbon content by a factor of two. The Z(eff) has been reduced from 2-2.5 to 1.4-1.5. A slight reduction of the loop voltage is observed. The radiation power decreases by a factor of 2, enhancing the high density operation limit with a consequent increase of the poloidal beta beta(theta) and of the energy confinement time tau(E).
Boronization with trimethylboron in the reversed field pinch RFX
1996
Abstract
The first wall and the vessel of the Reversed Field Pinch RFX has been in situ coated with a B/C:H film by glow discharge cleaning with a mixture of 12.5% of trimethylboron ((CH3)(3)B) in He. The film has been analysed and the effects on the plasma discharges of the boronized wall are reported for a plasma current of 520 kA. The main effects on the plasma are a reduction in the oxygen content by a factor of 5 to 10 and a decrease in the carbon content by a factor of two. The Z(eff) has been reduced from 2-2.5 to 1.4-1.5. A slight reduction of the loop voltage is observed. The radiation power decreases by a factor of 2, enhancing the high density operation limit with a consequent increase of the poloidal beta beta(theta) and of the energy confinement time tau(E).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
