Electrical discharge machining

Electrical discharge machining Electrochemical milling Electron beam machining Laser beam machining Ultrasonic machining... 

Other abrasive jet machining Electrostatic painting Electrical discharge machining Electrochemical machining... 

The main factors governing hydrogen embrittlement are the metal surface films that can restrict hydrogen absorption, the effect of electrical discharge machining that may... 

Because rhenium is very difficult to machine with carbide tools and other conventional methods, electrical-discharge machining (EDM), electrochemical machining (ROM), abrasive cutting, or grinding is... 

Liquid-phase carbonization occurs for some precursors, such as pitches, which become viscous fluids before carbonization. This process has been used to produce various polycrystalline graphite blocks for steel refining and electrical discharge machining, jigs for the growth of semiconductor crystals, structural components of nuclear reactor, etc. 

Ultrasonic machining (USM) is also of particular importance when very hard type materials are to be cut. As an assist to drilling, HDM energy can extend the drill life when producing holes in reinforced plastics. If the plastic is conductive, electrical discharge machining (EDM) or electrochemical machining (ECM) may be useful. 

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]. 

Electrode Materials for Electrical Discharge Machining, company brochure, Metallwerk Plansee, Reutte, Austrialia (1985). 

Electrodes for electrical discharge machining, arc erosion, and wire eroding (W,... 

W-Cu, V-ThO2). Electrical discharge machining allows close dimensional tolerances, accuracy of form, and a high-quality surface finish to be achieved. Both hardened steels and hardmetals can be machined (Fig. 7.12). Tungsten in wire eroding is not only used as a guide and contact for the wire electrodes, but also as erosion wire. 

FIGURE 7.12. Electrical discharge machining of a compacting die used in the production of gear parts. By courtesy of Plansee AG, Austria. 

A simplified model, where the heat brought to the substrate by the electrochemical discharges is approximated by a cylindrical uniform heat source of radius b and heat power P0 inside a homogenous material of density p, heat capacity c and thermal conductivity A, is considered (Fig. 5.2). Similar models have been applied successfully in electrical discharge machining [39]. 

The flexible structure can be used to machine metals by electrical discharge machining or polymers by conventional machining. The stiffness of the structure is controlled by the geometry of the four hinges. In the case of circular hinges the overall stiffness K is given by ... 

A.M. Gadalla, B. Bozkurt, N.M. Faulk Modeling of thermal spalling during electrical discharge machining of titanium diboride. Journal of the American Society 74 (1991),... 

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