Improvement of plasma performance with wall conditioning in the HL-1M tokamak

Studies and selection of plasma facing materials continue to be a concern for future fusion devices, and ongoing efforts are being made in the HL-1M tokamak. The advanced methods of wall modification adopted on HL-1M are surveyed. Significant improvements in tokamak plasma performance have been obtained by using boron, silicon or lithium containing substances as a material for wall coatings. The siliconization technique is highlighted. Lithiumization, as the newest technique, will be investigated further.