Research On Electrolytic Plasma Polishing Process Of Thermos Inner Surface

Electrolyte plasma polishing is a revolutionary and advanced technology in the field of metal surface treatment,which is reflected in its environmental protection,processing method,technology and application.The technology uses low concentration of neutral salt as electrolyte,which can grease marks,polish,and debur on complex surface of the metal workpiece,solving the low efficiency o f mechanical processing,electrochemical processing of environmental pollution and other problems.At present,this polishing technology has achieved remarkable results on the outer surface polishing of metal materials,especially on stainless steel.However,there is little research on the polishing of the inner surface,and the processing effect is far inferior to that of the outer surface.In this paper,the inner surface of thermos is taken as the experimental object,and the method of polishing the inner surface of stainless steel products by electrolytic plasma process is studied,in the hope of improving the processing quality and efficiency of polishing on the inner surface of thermos by using the characteristics of environmental protection and high efficiency,and solve the problems in the traditional polishing method.Based on the research of material removal mechanism of electrolyte-plasma polishing and the analysis of volt-ampere characteristic curve of different diving methods,the shape of thermos and the shortcomings of water pumping method,it is pointed out that the key to obtain good processing effect is to replenish polishing liquid into the bottle immediately during processing.Therefore,a new polishing method has put forward,which is applying voltage first and then immersing the thermos into the electrolyte.In the meantime,explore the influence of the center electrode on the uniform machining of inner space.According to the research requirements of process parameters,the processing power of 100 k W equipment is modified to meet the large range of pressure regulation of 250 ? 400 V.Design the automatic electrolyte circulation system and lifting mechanism and select the sensor.The polishing fixture is designed to meet the requirements of polishing the inner surface of thermos and the suitable materials are selected.Taking the surface roughness of four sampling points in the vertical direction as the index,study the influence of suspension angle,shape of cathode rod and insertion distance on the stability,uniformity and processing effect of inner surface polishing.The control variable method is used to carry out single factor experiment to find the influence of four process parameters,which are processing time,polishing temperature,processing voltage and polishing liquid concentration on the inner surface roughness of thermos.The basic regularity of the change of each factor and surface roughness is obtained.Besides,the best range has been found out.Based on the experimental results,establish a simplified polishing model of the inner surface of thermos by using COMSOL and solve the model.The distribution of electric field and electric potential in the inner space during the polishing process is calculated.The theoretical results obtained are consistent with the actual phenomenon.According to the calculation results,the shape of the cathode rod is improved and the simulation results show that the electric field distribution is more uniform.