Research On Sputtering Rale Of Plasma Materials

The working environment of plasma facing materials is very harsh,and the choice of materials determines the success of fusion reactor.Carbon based materials are important candidate materials for facing plasma materials because of their high temperature resistance,no melting,high thermal conductivity and thermal shock resistance.However,when plasmas(deuterium atoms,tritium atoms and helium atoms)bombard carbon based materials,the high sputtering yield and high tritium retention rate of carbon based materials seriously affect the further use of carbon based materials in fusion reactors.Therefore,the sputtering yield of carbon based materials is further studied in the article.This paper will use the method of Molecular dynamics and Monte Carlo to study the sputtering yields of graphite,silicon carbide and continuous carbon fiber reinforced silicon carbide materials.They will be calculated and compared respectively from three factors:the energy of incident particles,the type of incident particles and substrate temperature.Calculation results show that:(1)When the incident energy is 25 eV?50 eV,the sputtering yield of graphite reach the peak;When the incident energy is 200 eV,the sputtering yield of silicon carbide reach the peak;When the incident energy is 400 eV?500 eV,the sputtering yield of continuous carbon fiber reinforced silicon carbide materials reach the peak;(2)With the same incident energy,the sputtering yield of graphite>the sputtering yield of silicon carbide>the sputtering yield of continuous carbon fiber reinforced silicon carbide materials;(3)The type of incident particle affect the sputtering yield of graphite significantly,the sputtering yield increases with the increase of the mass of the incident atom;and the type of incident particle has little effect on the sputtering yield of silicon carbide and continuous carbon fiber reinforced silicon carbide materials;(4)The substrate temperature affect the sputtering yield of graphite significantly,the sputtering yield increases with the increase of the substrate temperature;but the substrate temperature has little effect on the sputtering yield of silicon carbide and continuous carbon fiber reinforced silicon carbide materials.In addition,this paper study the effect of incident angle and carbon concentration on continuous carbon fiber reinforced silicon carbide materials.We can get it by calculation:(1)when the concentration of carbon of continuous carbon fiber reinforced silicon carbide materials is about 0.60?0.62,the sputtering yield reaches the minimum value;(2)when the incident angle is less than 30 degrees,the sputtering yield does not change,when the incident angle greater than 30 degrees,the sputtering yield decreases with the increase of the incident angle.Based on the above considerations,carbon fiber reinforced silicon carbide is more suitable as a plasma-facing material.