Electric discharge machining (EDM), sometimes colloquially also referred to as spark machining, spark eroding, burning, die sinking,wire cut or wire erosion, is a manufacturing process whereby a desired shape is obtained using electrical discharges(sparks). Material(metal) is removed from the workpiece by a series of rapidly recurring current discharges between two electrodes, separated by a dielectric liquid(some sort of oil may be) and subject to an electric voltage.
One of the electrodes is called the tool-electrode, or simply the ‘tool’ or ‘electrode’, while the other is called the workpiece-electrode, or ‘workpiece’.
When the distance between the two electrodes is reduced, the intensity of the electric field in the volume between the electrodes becomes greater than the strength of the dielectric (at least in some point(s)), which breaks, allowing current to flow between the two electrodes. This phenomenon is the same as the breakdown of a capacitor . As a result, material is removed from both the electrodes. Once the current flow stops new liquid dielectric is usually conveyed into the inter-electrode volume enabling the solid particles (debris) to be carried away and the insulating properties of the dielectric to be restored. Adding new liquid dielectric in the inter-electrode volume is commonly referred to as flushing. Also, after a current flow, a difference of potential between the two electrodes is restored to what it was before the breakdown, so that a new liquid dielectric breakdown can occur and the process continues.
Such type of wire cut machines are used at various industries.
an Enhanced type of wire cut machines known as CNC(computerized Numeric Control) machines is also found for precise cutting and designing of metallic goods.
One of the electrodes is called the tool-electrode, or simply the ‘tool’ or ‘electrode’, while the other is called the workpiece-electrode, or ‘workpiece’.
When the distance between the two electrodes is reduced, the intensity of the electric field in the volume between the electrodes becomes greater than the strength of the dielectric (at least in some point(s)), which breaks, allowing current to flow between the two electrodes. This phenomenon is the same as the breakdown of a capacitor . As a result, material is removed from both the electrodes. Once the current flow stops new liquid dielectric is usually conveyed into the inter-electrode volume enabling the solid particles (debris) to be carried away and the insulating properties of the dielectric to be restored. Adding new liquid dielectric in the inter-electrode volume is commonly referred to as flushing. Also, after a current flow, a difference of potential between the two electrodes is restored to what it was before the breakdown, so that a new liquid dielectric breakdown can occur and the process continues.
Such type of wire cut machines are used at various industries.
an Enhanced type of wire cut machines known as CNC(computerized Numeric Control) machines is also found for precise cutting and designing of metallic goods.
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