Analysis of EDM process parameters on imprint mould surface texture

doi:10.13251/j.issn.0254-6051.2022.03.004

Abstract

Abstract: Circular micropit arrays with diameters of ø100, ø200 and ø300 μm and regular morphologies were prepared on the surface of graphite electrodes, the electrode was used to fabricate a micro bulge array imprint mold on the surface of 45 steel by electrical discharge machining (EDM). Effect of processing current on its surface properties was investigated. The surface morphologies of graphite electrodes and the 45 steel specimens treated by EDM were analyzed by means of ultra-depth of field microscope and scanning electron microscope. At the same time, Rockwell hardness tester, roughness tester and electronic balance scale with an accuracy of 0.01 mg were used to detect the micro bulge array on the surface of the 45 steel. Effect of processing current on material removal rate (MRR) of the 45 steel and the electrode wear rate (EWR) of graphite electrode was discussed. The results show that, the micro bulge array with corresponding size is successfully formed on the surface of the 45 steel by the principle of EDM reverse etching, and the higher surface microhardness and surface roughness values are obtained, which increase with the increase of EDM current, among them, the specimen with ø200 μm micro-bulge obtains a maximum microhardness of 34 HRC, and the specimen with ø300 μm micro-bulge obtains a maximum surface roughness of 12.56 μm. In addition, when the diameter of the micro-pits or micro-bulges on the specimens is constant, the MRR and EWR values also increase with the increase of processing current.

Key words: EDM, laser processing, 45 steel, graphite electrode, micro pit, micro bulge

CLC Number:

TG661

Liang Huainan, Liu Zhiqi, Chen Dongliang, Song Jianli, Lin Naiming. Analysis of EDM process parameters on imprint mould surface texture[J]. Heat Treatment of Metals, 2022, 47(3): 20-27.

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