Study On Electrode Wear Regulation Of Edm Forming Process For Micro And Complex Curved Surface

In the fields of aerospace,biomedicine,photoelectric communication,mold manufacturing,many key components have micro complex surface feature.It’s hard to manufacture the hard-to-processing materials accurately in transitional methods under the special working conditions,especially,when the scale feature in micro-magnitude.However,EDM has no limitations on the hardness,strength of the materials,which is an effective method to manufacture the micro complex surface on the hard-to-process material.In comparison to the electrical discharge milling machining,electrical discharge has advantages of high efficiency of electrical discharge forming,easily control,less wear of electrode.Because of the wear of electrode is inevitable during the manufacturing process,the deformation of electrode makes difference,which is hard to get the imaging structure.This paper refers to utilize the electrode wear characteristic to accomplish the manufacture forming of micro complex surface based on the problems of lower efficiency of manufacturing and electrode wear on electrical discharge manufacturing the micro complex surface,which is considering to using the influence of electrode wear with changes of electrode during the electrode designing process through making multi-material electrode to manufacture the micro complex surface directly and efficiently.The paper researches on the following works:(1)In order to predict the law of electrode erosion,utilizing ANSYS to set up the 3-D module of single-material and multi-material electrode erosion under the condition of monopulse separately.Applying the single factor method to research on the influencing law of peak current,discharge voltage,pulse width,electrode material and the difference between single-material and multi-material electrode erosion rate of the same electrode material getting the temperature distribution of single-material and multi-material electrode in radial direction and the difference of peak point position of temperature.Carrying on the experiment on the self-made electrical discharge machine and verifying the result of simulation and researching on the influence of end surface discharge probability distribution of electrode shape changes.(2)Applying single factor experimental method researching on the law of electrode wear between single-material and multi-material separately.Analyzing the influence of electrode material,component material,manufacturing polarity on the length of electrode wear and angular wear,as well as the relationship among the elements of multi-material electrode.Based on the above mentioned,researching on the graphite and brass single-material electrode shape changes law and brass-die steel,copper-tungsten alloy-red copper of multi-material electrode changes law.After that,this paper finds that the electrode erosion slows down with the better thermal conductivity,the higher melting point,and the higher specific heat capacity,and the slower speed of erosion,the easier sphere electrode will create.Via analyzing the transition surface of connecting field after manufacturing the multi-material electrode,the arc radius angle and radius of multi-material in the connecting field is constant.(3)Using certain micro complex surface as an aim,according to the requirement of manufacture designing a group of multi-material electrode to realize the micro complex surface foaming manufacture.Using Hyper depth of field 3D microscope system to obtain the outline curve in different position of micro complex surface and compared to the aiming curve to get the final analyze,discovering the measuring curve is nearly matching the aiming curve and the biggest dimension error is 6.7%,which approves this method can be better to realize the micro complex surface manufacture.