Research On The Treatment Of Hard Water Dielectric Fluid And Invalid Dielectric Fluid Of HSWEDM

High-speed wire electric discharge machining(HS-WEDM),which is self-developed by China,has been widely applied in aerospace,mold machining,military industry and other areas,and has become an irreplaceable processing method in the machinery manufacturing industry.With the continuous expansion of its application area,the difference in water quality caused by the difference in the use performance of the working fluid has great influence on the processing efficiency and surface quality.At the same time,after the working fluid is used for a period of time,the electric field and the high temperature are interposed.Under the circumstances,physical properties change,processing performance reduction needs to be replaced regularly,if the failed working fluid is discharged directly without treatment,it will cause serious pollution to the environment.In view of the above problems,this paper explores the discharge mechanism,treatment mode and recycling of hard water working fluids;analyzes the characteristics of existing water treatment methods and spent working waste liquids,and treats the recycling methods and recycling of working waste liquids.The research was carried out and the main contents are as follows:(1)Designed the cutting process test of hard water working fluid and distilled water working fluid,studied the influence of hard water working fluid on the surface and cutting efficiency of the workpiece,and cut the surface morphology,composition analysis and pole from the hard water cutting surface.In the aspect of the discharge waveform,the mechanism of the loss of metallic luster and the reduction of cutting efficiency on the surface of the hard water working fluid was studied.It is believed that the fundamental reason for the loss of metallic luster on the surface of the workpiece treated by hard water is that the Cl~-in the hard water is adsorbed on the surface of the workpiece under the action of the electric field between the poles.Due to the strong penetration ability of Cl~-,the formation of pitting on the surface of the metal makes it possible.The cutting surface loses the metallic luster;the cutting efficiency of the hard water working medium is reduced because the hard water working medium contains more impurity ions,and the colloid adsorbing in the working fluid causes the working fluid to lose dielectric properties,and the etching rate decreases;At the same time,since the hard water working medium has stronger conductivity and is easily broken down,the inter-electrode discharge gap is increased,so that the cutting efficiency is further reduced.(2)By analyzing the hard water and the spent working fluid,it is finally treated by evaporation condensation.In view of the use characteristics of the wire cutting working fluid,the design of the evaporative condensation test system is mainly carried out,including the design of the evaporative condensing device,the design of the evaporative condensation control system hardware and software,and the design of the temperature PID algorithm for the evaporation of hard water and work.The waste liquid provides a test platform.Using the designed evaporation condensing system,the evaporation test of hard water and working waste liquid is carried out,and the optimum evaporation temperature of hard water and the working fluid is studied from the perspective of evaporation efficiency and water quality of evaporated water.(3)Through the process comparison test with distilled water working fluid,the processing performance of hard evaporating water and evaporating water of waste liquid was studied from the processing efficiency and the surface angle of the workpiece.The test proved the processing performance of hard evaporating water and evaporating water of waste liquid.The distilled water is basically the same,indicating that the use of evaporation to extract water from the"waste liquid"is an effective method for treating the waste liquid.