Metal spark erosion, also known as electrical discharge machining (EDM), is a non-traditional machining process that uses electrical discharges to remove material from a workpiece. Here's a simple explanation:
Setup:
A tool (electrode) and a workpiece are submerged in a dielectric fluid (usually oil or deionized water).
Electric Discharge:
An electric potential is applied between the tool and the workpiece. When the tool comes close to the workpiece, sparks or electrical discharges occur.
Material Removal:
The electrical discharges generate intense heat, melting and vaporizing small particles of the workpiece. These particles are flushed away by the dielectric fluid.
No Physical Contact:
Unlike traditional machining processes, there is no direct contact between the tool and the workpiece. Material removal happens through the action of electrical discharges.
Precision Machining:
EDM is known for its ability to machine intricate and complex shapes with high precision.
Types of EDM:
Wire EDM: Uses a thin wire as the electrode to cut through the workpiece.
Sinker EDM (Ram EDM): Uses a shaped electrode to create a cavity or form in the workpiece.
Applications:
EDM is used for machining hard and electrically conductive materials, such as tool steel, titanium, and carbide.
Advantages:
Ability to machine complex shapes.
Minimal tool wear.
Can be used for materials that are difficult to machine with traditional methods.
In simple terms, metal spark erosion or electrical discharge machining is a process where material is removed from a workpiece by generating electrical discharges between a tool and the workpiece submerged in a dielectric fluid, allowing for precise and intricate machining.