Online surface coating silicification wall treatment method for fusion device

Abstract

The invention belongs to a vacuum technology in the field of fusion, and particularly relates to an online surface coating silicification wall treatment method for a fusion device. Mixed gas of deuterium silane and helium is used as working gas for silicification wall treatment, an injection point is arranged on a vacuum chamber, a piezoelectric crystal valve is used for supplying gas, a pulse working mode is adopted, and the gas supply pulse moment is 300-1800 ms of a flat top section where plasma of an HL-2A device operates; and after entering the vacuum chamber, the deuterium silane-helium mixed gas moves to the scraping layer area along the radial direction, and then deposits on the inner wall of the vacuum chamber to form a silicification wall under the action of the plasma. The silicification film formed by the method has very strong adsorbability to oxygen, oxygen impurities in the vacuum chamber can be reduced in real time, and device wall conditions are optimized, so that plasma operation parameters are improved.

Description

technical field [0001] The invention belongs to the vacuum technology in the field of fusion, and in particular relates to an online silane gas feeding surface coating wall treatment method for fusion devices. Background technique [0002] Impurity suppression is an important issue in the operation of tokamak devices. The current tokamak device needs to limit the impurities in the plasma through the first wall tempering to obtain high-quality plasma. Commonly used wall treatment methods include wall cleaning technology (DC glow) and first wall surface coating technology (silicidation, lithiation). Among them, silicidation is usually performed by plasma-assisted vapor deposition in advance. Experiments have proved that the carbon and oxygen impurities in the fusion device are significantly reduced by adopting the silicide wall treatment method, and the radiation power loss is also significantly reduced. Therefore, siliconized wall treatment is an important wall treatment m...

AI Technical Summary

Problems solved by technology

Fusion devices with long-pulse steady-state operation, due to long-term operation and high temperature, will generate more impurities and fuel gas retention during operation, if not handled in time, it is very likely to cause interruption of steady-state operation

However, glow discharge cleaning cannot operate under strong magnetic fields, and pre-coated films are quickly eroded or covered

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