Erosion of a carbon coated molybdenum limiter in TEXTOR
The erosion of thin amorphous carbon layers on a molybdenum test limiter by ohmic tokamak discharges was studied in TEXTOR. The layers were progressively eroded at the areas of largest heat load and molybdenum release. The erosion pattern cannot be explained by the topology of the magnetic flux surfaces alone, but a poloidal rotation or an equivalent poloidal plasma flow has to be postulated. Good correlation between the amount of molybdenum collected in the scrape-off layer and the intensity of the Mo XXIV line emitted from hot plasma regions was observed. The observations indicate that the prolonged use of unprotected molybdenum limiters will lead to proliferation of molybdenum. Post mortem analysis of the limiter surface reveals the importance of thermal processes for carbide formation and migration of carbon in molybdenum.
Bibliographic Reference: Article: Contributions to High-Temperature Plasma Physics (1994) pp. 431-444
Record Number: 199411637 / Last updated on: 1995-01-10
Original language: en
Available languages: en