Experimental Research Of Plasma Facing Materials In J-TEXT Tokamak

Plasma facing materials(PFMs) play an important role in parameter and control of plasma during tokamak fusion. In J-TEXT tokamak, some studies about plasma facing materials(PFMs) has been run.This paper introduces the research and focuses on the analysis and explanation of process and phenomenon involved.At the beginning of this paper, experiments are carried out with graphite tiles used in J-TEXT tokamak. We select PFMs located on the high field side of the vacuum chamber as specimens and analyze the morphologies and chemical composition on the surface. There're several diagnostics involved such as scanning electron microscopy(SEM), X-ray photoelectron spectroscopy(XPS), solid scattered diagnostics(SSD) and energy dispersive spectroscopy(EDS).The result shows that there's a big difference among different sections. Distinct injury degree makes a large gap in the life time of different specimens.Recent years, a lot of work has been done on the effect of resonant magnetic perturbation has on plasma in J-TEXT tokamak. In consideration of the local interaction of plasma and surface may be interrupted as applied magnetic perturbation field changes the topology of magnetic field boundary. This paper selects three typical plasma facing materials as specimensand runs the experiment. After a round of discharging experiment, it shows that there are significant differences in erosion and deposition on the two sides of magnetic perturbation coils. According to the direction of plasma, materials in upstream endure more deposition than in downstream. Comparing the effect of plasma has on the materials of the limiter's two sides, it's clearly that the deposition in upstream of magnetic perturbation coils comes from the limiter. However, the result has not been able to clearly show specific effect of magnetic perturbation.This paper can provide a reference for the design and improvement of J-TEXT tokamak PFMs in the future.