Study On Electrolytic Removal Of Recast Layer By Micro-EDM

Micro-EDM technology is widely used in the field of microfabrication due to its low cost,processing of various metal materials,non-contact processing,and no machining advantages such as macro cutting force.However,the processing mechanism of the fine electric spark high-temperature molten metal makes the surface of the processed workpiece have a thin re-cast layer composed of etch pits,protrusions and pores,which seriously affects the surface topography and precision of the processing,in aerospace,There are security risks in the application of medical and other fields.Therefore,on-line,quantitative,and directional removal of microstructured surface recast layers has become an urgent problem to be solved.Firstly,the paper analyzes the forming mechanism of the recast layer.According to the characteristics of the coagulation of the workpiece material and the tool material,a method for measuring the thickness according to the composition of the different depth elements of the recast layer is proposed,and the thickness is electrolytically removed as the recast layer.Standard.At the same time,the electrolysis removal mechanism of recast layer was analyzed,the basic conditions of electroforming of recast layer were clarified,the processing model was established,and the removal process of recast layer was simulated.Then,the electrolysis removal process of the recast layer was studied,and the influence of process parameters such as electrolyte composition,concentration,temperature,processing voltage and initial processing gap on the electrolysis removal of the recast layer was analyzed.Through the experiment,the surface removal process of the recast layer was studied.In order to realize the quantitative removal of the recast layer,the method of adjusting the equivalent processing time by the trajectory processing interval and the feed rate was proposed,and the re-casting layers of the micro-planar,micro-hole and sidewall were removed online.Next,the online removal technology of the recast layer was studied.A micro-EDM-electrolytic combined processing platform was designed to develop a micro-EDM-micro-electrolysis multi-function pulse power supply.A working fluid circulation system was designed to meet the two process conditions,and a matching control system software was developed to enable it to be used.Micro-EDM and micro electrolytic machining.Finally,for the combined processing platform,a micro-EDM-electrolytic combination process integration method was developed,and a special three-dimensional structure of micro-EDM and surface recast layer on-line removal experiments were carried out to remove the thickness of 12.531?m.The surface roughness decreased from 1.426?m to 0.266?m,and a good removal effect was obtained.