Electric discharge machining works on a principle of using an electric spark to remove the metal burr. An electric spark, if used as a cutting tool, can help cut metal to create the desired shape. This can be done by applying a high-frequency current through electrodes and the spark that is produced removes the metal in small chips and is generally conducted in a dielectric liquid. The electric discharge machining works on the process of principle, equipment, workings, etc.
The basic principle here is the generation of spark erodes the metal. The method is similar to an electric spark that burns a hole in the metal that it contacts. The spark produces heat, which burns away the metal by evaporation and erosion. For the process to work effectively, the workpiece and also the tool should work under a conductive material.
The Pieces of equipment
- For the electric discharge machining to work, they are certain equipment required such as
- a constant flow of power to help generate sparks
- A dielectric fluid to help drive away the chips, and to prevent them from sticking to each other causing a short-circuit
- Due to the sparks produced the tools also erode and it becomes important to select your tools carefully
- This mechanism can work only on metals which are a good conductor of electricity, and it is crucial to make sure that the workpiece and the tool is also a good conductor of heat and electricity.
This process requires a workpiece that is a good conductor of heat and electricity. The workings of Electric discharge mechanism includes:
- The workpiece and the tolls are submerged in a dielectric fluid
- A servomechanism to maintain a gap between the workpiece and the tool
- A high-frequency current is supplied to produce a spark which generated heat and electricity
- The metal is removed due to erosion and evaporation
- The suspended metal chips should be removed to prevent from causing a bridge that can result in short-circuit
- Even the EDM produces a cavity as the materials used are a good conductor of heat and electricity.
Only conductive materials can be used in the cutting process
Complex shapes and dissection can be produced
The sectioning can be done without deforming the parts
The hardness of the workpiece can be machined easily
The process is free of burr
Due to the tools being a good conductor of heat and electricity, there is a high chance of tool wear
The tool wear may cause disruptions in the finishing of the metal
EDM process can only work on metals which are a good conductor of heat and electricity