Electro Discharge Machining

E E(t) EDM EDTA EDX EHD EKI EO EOF ESI-MS Ez Activation energy Exit-age distribution function Electro-discharge machining Ethylene-diamine-tetraacetic acid Energy dispersive X-ray Electrohydrodynamic Electrokinetic instability Electroosmotic-Electroosmotic flow Electrospray ionization mass spectrometry Electric field... 

Micro electrical discharge machining (EDM) is primarily used for hard metals and other electrically conductive materials. When two electrodes separated by a dielectric medium come close, the dielectrical medium breaks down and suddenly becomes conductive. Sparks generated between the electrodes release energy and remove metal by melting and evaporation [30], Murali and Yeo combined micro electro-discharge machining with ultrasound electrode vibration for improved surface quality, and achieved micro features as small as 25 pm on titanium with 20 pm diameter electrodes [30]. 

Stampfl, J. Leitgeb, R. Cheng, Y.-L. Prinz, F.B. Electro-discharge machining of mesoscopic parts with electroplated copper and hot-pressed silver tungsten electrodes. J. Micromech. Microeng. 2000, 10, 1-6. 

I.Z. Ismagilov, R.P. Ekatpure, L.T. Tsykoza, E.V. Matus, E.V. Rebrov, M.H.J.M. De Croon, M.A. Kerzhentsev, J.C. Schouten, Optimization of anodic oxidation and Cu-Cr oxide catalyst preparation on structured aluminum plates processed by electro discharge machining, Catal. Today 105 (2005) 516. 

Nachiappan Ravi, Han Huang, Fabrication of symmetrical section microfeatures using the electro-discharge machining block electrode method, J. Micromech. Microeng. 12 (2002) 905-910. 

Micro electro discharge machining 10-25 0.05-1 50-100 Conductive materials... 

Tooling. Tooling is relatively expensive for injection molds. Production molds are normally machined and burned (electro-discharge machined) from tool steels (P20) and must be sfructured to withstand high pressures. Precision is required to incorporate cooling lines, ejector pins, and cavity pressure transducers or temperature monitoring sensors. The use of hot runner manifolds adds further complexity and cost, but may be justified because cold runners and their associated costs are eliminated in manufacturing. 

Figure 1. Different samples machined by electro-discharge machined from disks (bottom raw)...

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