ELECTRIC DISCHARGE MACHINE-EDM

In the Electric Discharge Machine process, an arc is produced when two current-carrying wires are short-circuited. During this machining process, a small portion of metals is also eroded, leaving a small cater. this phenomenon is used in electric discharge machining (EDM). EDM machining process is also known as a spark erosion machine.

ELECTRIC DISCHARGE MACHINE PROJECT

involves a controlled erosion of electrically conductive materials by the initiation of rapid and repetitive spark discharges between the tool and workpiece separated by a small gap. Each electrical spark produces sufficient heat to melt a portion of the workpiece and usually, some of the tooling materials also. Due to rapid heating, the dielectric fluid evaporates in the arc gap which increases the resistance until the arc is interrupted. The associated shock wave and flowing dielectric fluid remove the gas bubbles which later collapse.

 EDM Machines Used

The electrical discharge machine is a machining method primarily used for hard metals or those that would be very difficult to machine with traditional techniques. EDM typically works with electrically conductive materials, although methods have also been proposed for using EDM to machine insulating ceramics.

PRINCIPLE OF EDM

Electrical Discharge Machine (EDM) is a controlled metal-removal process that is used to remove metal using electric spark erosion.  In this process, an electric spark is used as the cutting tool to cut (erode) the workpiece to produce the finished part to the desired shape.  The metal-removal process is performed by applying a pulsating (ON/OFF) electrical charge of high-frequency current through the electrode to the workpiece. This removes (erodes) very tiny pieces of metal from the workpiece at a controlled rate.

Types of Electrical Discharge Machine

1 Wire EDM: In Wire EDM, the electrode is a brass wire that comes off a spool and is fed through an upper and lower diamond guide, and then discarded after it is used. The wire is controlled by a CNC control which allows you to program a path for the wire to travel.

2 Sink EDM: Also referred to as “Plunge EDM” or “Ram EDM,” in Sink EDM the electrode is a machined shape and the machine uses this shape to erode the inverse shape in the workpiece. This process is also very accurate and commonly used to burn mold cavities where the electrode starts the shape of the final molded part and is used to erode a cavity in a mold that is later used to make thousands or millions of parts.

WORKING OF EDM PROCESS

•  The tool is fed up by the Servo Feed Unit which can move downward in a vertical direction.
•  The power supply is given to the electrical discharge machining process I.e. Positive terminal is given to the workpiece and a Negative terminal is given to the tool.
•  The tool and workpiece are separated using dielectric fluid and an optimum gap is maintained between them.
•  When positive and negative ions collide with each other then the spark is generated between the tool and workpiece which can remove the material from the surface of the workpiece.
• This is a detailed explanation of the Electrical Discharge Machining process along with the basic terms and working.

Applications of EDM:

•  It is used for producing a hole size of less than 0.1 mm.
•  Used for die sinking or die manufacturing.
• Holes in the air brakes or Pneumatic Brakes were done by an electrical discharge machining process.

ADVANTAGES OF ELECTRIC DISCHARGE MACHINE

• the machining process does not depend on the mechanical properties of the workpiece.
• No residual stresses will be generated because no forces are acting.
•  The deeper hole is possible to produce (L/D) up to 20.
• Out of all the non-traditional machining methods, EDM is the method with higher Material Removal Rate (MRR).
• The surface finish is better due to melting and vaporization.

DISADVANTAGES OF ELECTRIC DISCHARGE MACHINE

• Used only for electrically conductive material.
• Electrode wear is more.
• Re-hardening occurs due to heat generated during machining.
• Not possible to make exact square corners.

CONCLUSION;-

The project ‘Electric Discharge Machining’ has a huge market in the present industrial scenario. The EDM is widely used in Sheet Metal operations worldwide including the ones at HAL Sunabeda. Hence the learning and experience of the industry were worthwhile.

IN CASE KIND OF PROJECTS

All of the above; If this article is not working for you. So you can contact with the subject of your specific project. And we will lead you, to get that kind of project as soon as possible. If in case you are feeling to buy a project for an Electric discharge machine(EDM); simply contact us. And for your convenience; that we provide all BTech mechanical final year engineering projects.