Design And Experimental Study Of Ion Source For Coating

The coating technology on the surface of materials can effectively reduce the waste.The maturity of coating technology affects the quality of coating,and also determines the applicability of coating.Plasma assisted deposition can achieve higher adhesion and uniformity,more and more attention are paid to this technology.Based on the analysis of plasma assisted deposition technology at domestic and abroad,aiming at improving the quality and efficiency of coating,the design,processing,simulation and experimental research are carried out to the ion source.The working demand of ion source is optimized,and the matching relationship between voltage and magnetic field intensity is deduced and verified,At the same time,the optimization of plume is carried out,which provides a reference for the optimization of plasma assisted deposition technology.The magnetic circuit structure analysis and design for the application direction of coated ion source are carried out.The cylindrical Hall thruster structure is used for reference,the magnetic circuit and the whole machine are designed and processed without a wall.The obtained ion source can achieve stable discharge work,and can better satisfy the research needs and coating performance requirements of this topic.The influence of working environment on the discharge characteristics of ion source was studied.The working environment mainly includes working gas and vacuum back pressure.The discharge characteristics of krypton and argon ion source are explored through experiments.It is found that argon has better coating characteristics although its stable working range is small,The influence of vacuum back pressure on the discharge characteristics was studied by adjusting the flow control valve and the number of diffusion pumps.The ionization simulation under different background pressures was carried out by adjusting the backflow of background gas.It was found that the increase of vacuum pressure would affect the ionization acceleration characteristics,increase the plume divergence angle and reduce the ion energy distribution in the plume.The voltage and magnetic field intensity matching relationship of the ion source with this structure was established,and the experimental verification was carried out to realize the multi working condition target of ion energy change under constant current.Through the anode magnetic shielding technology,the anode thermal deposition is transferred to the inner magnetic pole without potential,and the temperature simulation of the whole machine is carried out for the overheating phenomenon of the magnetic pole.Based on the previous experimental ion current distribution,the plume optimization design was carried out.Through experiments and simulation,the plume optimization of ion source was realized by adjusting the magnetic field line inclination angle of plume area with expanded plume divergence angle,adjusting the negative potential of external electrode,improving the uniformity of plume by central axial,anode bevel mixed gas supply and anode radial gas supply.