EDM (Electrical Discharge Machining) is an unconventional metalworking process that uses spark erosion to remove material from the workpiece. Electric discharge (spark) is usually generated between the electrode of the wire and the part to be processed. There is usually a low-conductivity liquid medium between the two, such as deionized water. As the work progresses, the medium will be continuously washed. The track is cut to a certain length and it is easy to handle any number of moving blocks. In most projects, two moveable blocks per rail and 2 rails per axis are present.
The lead screw of a CNC EDM wire cut transforms the rotary motion of the movement into linear motion. Other CNC machines (such as CNC milling machines and plasma cutting machines) may make use of alternatives to lead screws, such as drive belts or racks and pinions, but lead screws for CNC milling machines are the most common solution.
The lead screw turns rotary motion into linear motion, and the friction and gap should both be as small as possible. In several dimensions, the cutting line can move at a wide-angle. The taper would be sliced into the workpiece by this. This is particularly useful for the manufacture of extrusion dies. By moving the wire through the hole previously drilled, the cut can be made. In addition to metals, CNC EDM wire cut for machining may also be used for other conductive materials (such as graphite, diamond, and metal alloys).
Phase for Wire EDM
Wire EDM is one of the most common EDM methods. As the wire reaches the workpiece, the square of the gap increases with the electric field. The dielectric material will finally enter the spot where electrical breakdown takes place, and sparks will shoot through the distance between the wire and the workpiece, allowing the current to corrode them. The welding wire is used to keep the electrode from being so corroded so it can be wrapped constantly.
The steel wire is usually constructed from a single brass and fixed by a diamond-shaped guide at the top and bottom. In the x-y plane, the guide can move, and on three axes, the upper guide can move independently. In this way, it is possible to process tapers and other complicated, complex, and fragile forms. The CNC computer controls the guide rail and the workpiece. The average diameter of the wire is 0.25 mm, and the spool is about 10 miles long.
The incision is smaller than the wire diameter so the wire does not directly contact the workpiece, and because of sparks from the wire to the workpiece, "cutting" happens. The cut can be between plus and minus microns if the smallest diameter wire is used. Usually, modern CNC EDM wire cut machine tools have several cutter heads to cut more than one workpiece and do wire threading automatically.
Application of CNC EDM Wire Cut
Wire-cut electrical discharge machining (WEDM) is used to cut hardened metal plates with a thickness of 300 mm, which are usually difficult to machine in any other way. It can also be used when the final part requires low stress. Wire EDM has low cutting force, can remove material, and has little mechanical change properties. In the development of extrusion dies, blanking punches, and tool manufacturing, CNC EDM wire cut is used. For comparatively low production volumes of products requiring close production tolerances, CNC EDM wire cut is better used. The semiconductor, medical, and instrumentation industries are among the industries that make use of components provided by EDM.
EDM's benefits require machining of:
● Complex shapes that traditional cutting tools would otherwise be difficult to cut
● A particularly difficult substance with very narrow tolerances
● Quite small work bits where the component can be destroyed by unnecessary cutting tool pressure resulted from traditional cutting tools.
● No direct communication occurs between the instrument and the workpiece. Delicate bits and fragile materials can then be treated without any distortion.
● It is possible to achieve a strong surface finish.
● It is possible to drill very fine holes quickly.
Forms of EDM Wire Cut
Two key forms of EDM are available: traditional, or sinker, and cable, or wire cut. EDM sinker is the method that spreads the electric current, as mentioned above. The cathode runs along with the metal. In order to melt or vaporize the metal, the workpiece, the anode, and the electric current react. The cathode and the workpiece are immersed in the dielectric fluid since it is normally a hydrocarbon liquid. The tiny fragments formed by this process are washed away from the workpiece.
The charged current is emitted into a tensioned thin wire by CNC EDM wire cut, which serves as a cathode and is directed along the desired cutting path or incision. In this situation, during the cutting process, the dielectric fluid (usually deionized water) will be flushed through the incision, taking away debris and regulating sparks. With narrow cuts (usually around 0.015 inches, finer cuts are available), thin wires may be precision cut, and potential tolerances are +/- 0.0001 inches. Higher precision facilitates intricate three-dimensional cutting and produces extremely precise punches, dies, and punches stripping templates.
A computer numerical control (CNC) instrument that can control the wires offers greater stability on the three-dimensional axis is controlled by the wire-cut EDM equipment. By changing the x-y coordinates of the instrument, simple cutting is accomplished, whereas more complicated cutting is accomplished by adding a movement axis to the wire guide. It is possible to use both four-axis and five-axis cutting machines and facilities. Standard EDM does not always generate small corners or very complex patterns, whereas complex patterns and cuts can be realized by the improved precision of wire EDM.
Moreover, conventionally, EDM wire can cut metals with a thickness of just 0.004 inches and thicker materials over 16 inches. For a certain thickness of the material, CNC EDM wire cut can only evaporate the metal, removing potential debris. On both edges, the wires of the WCEDM system will ignite, meaning the cut needs to be thicker than the wire itself. In other words, because the wire is surrounded by a current circle, the ring and line technicians can easily solve this problem with the smallest and most precise cutting direction. To make cuts narrower and much more reliable, manufacturers continue to create thinner and thinner wires for CNC EDM wire cut.