Copper Tungsten As an EDM Electrode Material
While graphite has long dominated the landscape of the edm electrode market, copper tungsten is gaining ground as the electrode material of choice for more intricate geometries and sharp corners. Using powder metallurgy methods, copper tungsten is made from an alloy of copper and tungsten. This composite is ideal for achieving high speed cutting, good flushing conditions, and minimal wear on the electrodes.
Electrode wear is one of the most significant factors that determine how well an EDM job will perform. Excessive electrode wear can lead to increased tool costs, increased production times and even failure of the workpiece. Achieving the best possible electrode wear is a combination of many factors, including machine settings, power and amperage, and the specific EDM grade used for a particular application.
As an example, copper has a low melting point that allows it to handle more current than graphite. However, this high current density also concentrates more heavily on sharp edges and corners. Graphite, on the other hand, can take the same current as copper but is more effective in machining the workpiece because of its lower melting point.
Another important factor is how easy an electrode material is to machine. The process of machining an electrode is very similar to the EDM process itself, so the electrode material must be able to easily absorb and dissipate energy. In addition, the strength of an electrode is a critical consideration, as it must be able to resist damage from handling and the EDM process itself.
