Wire EDM or Electrical Discharge Machining is a technique used to slice through metal. The technique uses thin brass wire for the purpose and can create intricate profiles with the process. The EDM machine uses spark discharges that are fast, repetitive, and controlled for cutting. This process works with electrically conductive metals. The process is specially suited for contours and cavities that are not possible with other cutting tools.
The EDM Process
EDM is also known as “spark machining” as it uses repetitive electrical discharges to remove metal. The electrical discharges are passed between the metal part and the electrode. A stream of continuously flowing liquid is used to remove the metal remnants produced during the process. A set of successively deeper craters is formed till the final shape is created by the discharges.
Different types of EDM
Ram EDM – In ram EDM, a graphite electrode is used along with traditional tools. This electrode is connected to the ram with the help of a power source and is fed into the work piece. The whole process is carried out in a fluid bath. The fluid helps to flush away the material, serves as a coolant to reduce the heat, and acts as a conductor for passing current between the workpiece and the electrode.
Wire EDM
In this method, a thin wire is used as an electrode. The wire is fed in the metal and the discharges are used to cut the material. The process is carried out in a bath of water. When closely observed, you can see that the wire does not touch the metal. All the cutting work is done by the electrical discharge. Computer software controls the whole operation including the path of the wire. The process can produce all sorts of complex shapes that are very difficult with other processes.
Advantages of Wire EDM Cutting Allows cutting intricate internal and external shapes along with tight radius contours.
It is a low cost process when the quantity is low or when the surface area of the cut edge is small.
Specifications for Wire EDM Cuttng
The process can be used on material such as titanium, steel, super alloys, aluminum, brass, and most other metals. It requires only software programming tooling to carry out the procedure.
Electrical discharge machining (EDM) is a non-traditional form of precision machining that uses thermal energy instead of mechanical force to remove material from a workpiece. It is sometimes referred to as Spark Machining since it utilises electrical sparks that are near 8000º C to 12000º C. Engineers often turn to EDM when machining processes such as CNC milling and CNC turning cannot produce the desired cut, such as sharp internal corners or a particularly deep cavity.
Electrical discharge machining is an excellent method to use in conjunction with a traditional machining method such as CNC machining when parts have specific geometrical requirements. Also, the ability of the process to machine hard materials make it an attractive option when working with metal materials . However, the machining process is relatively slow, so high-volume tasks are not well suited for this method.