This document discusses electrical discharge machining (EDM) and wire cut electrical discharge machining (WC-EDM). It provides a brief history of EDM and describes the basic working principles and processes of both EDM and WC-EDM. Key details covered include the use of a continuously moving wire, deionized water as the dielectric, and melting/vaporization of material. Advantages like high accuracy and ability to machine complicated shapes are contrasted with disadvantages like high energy consumption.

3.  Name Roll no
1. Muhammad Shaban 13-MT-03
2. Ali Gohar 13-MT-50
3. Tahir Hanif 13-MT-35

4.  Thermal Removing Techniques
 HISTORY OF EDM
 Introduction
 EDM Working principle
 Important characteristic
 Working

5.  Advantages
 Disadvantages
 Application
 Wc-edm
 Working principle
 Important characteristic

6.  Major components
 W-c edm Process
 Advantages
 Disadvantages
 Application

7.  In thermal removing processes, thermal
energy, provided by a heat source, melts
and/or vaporizes the volume of the material to
be removed.
 Among thermal removal methods, electrical
discharge machining or EDM is the oldest and
most widely used.

8.  In1770s, discovered by Joseph Priestly.
 Developed in the mid 1970s
 In the mid 1980s, the EDM techniques were
transferred to a machine tool
 Today, it is a viable technique that helped
shape the metal working industry.

16.  Electrical discharge machining wire cutting
(EDM-WC) is a thermal mass-reducing process
that uses a continuously moving wire to
remove material .
 A thin wire of brass, tungsten or copper is used
as an electrode.
 Deionized water is used as the dielectric.
 With wire edm you can basically cut out any
design.

17.  The working principle is based on
thermoelectric energy. This energy is created
between work piece and tool.

18.  Tool material : brass, tungsten or copper
 Work piece material :conducting material and
alloys.
 Process parameters : voltage, spark gap and
melting temperature of work.
 Material removal : Melting and vaporization
 Wire diameter : 0.25mm
 Kerf width : 0.41mm
 Die electric flushing pressure :
( 10 -15 kgf/𝑐𝑚2 )
 Spark gap : (kerf width –wire dia/2)mm

19. 1. CNC .
Process is controlled by CNC.
2. Power supply .
Provide energy to the spark.
3. Mechanical section .
worktable,workstand,wire drive mechanism.
4. Dielectric system.
The water reservoir where filtration , condition
of water(resistivity/conductivity)and
temperature of water is provided and
maintained.

21.  In this process, a thin metallic wire is fed on-to
the work piece, which is submerged in a tank
of dielectric fluid such as deionized water.
 The wire, which is constantly fed from a spool,
is held between upper and lower diamond
guides. The guides are usually CNC-controlled.
 In the wire-cut EDM process, water is
commonly used as the dielectric fluid. Filters
and de-ionizing units are used for controlling
the resistivity and other electrical properties.
 Wires made of brass are generally preferred.

22.  The area where in discharge takes place gets
heated to very high temperatures such that the
surface gets melted and removed. The cut particles
(debris) get flushed away by the continuously
flowing dielectric fluid and keep the wire and
workpiece cool.
 The wire and workpiece must be electrically
conductive.
 Schematic illustration of the wire EDM process. As
much as 50 hours of machining can be performed
with one reel of wire, which is then discarded.
 Pieces over 16 in thick can be machined.

24.  Machining accuracy is higher.
 As the cutting path is very small, there is very
less removal ratio of material.
 During machining, electrode wire doesn’t
touch work piece, there is no physical cutting
force.
 There is very little heat impact on the surface of
work piece
 It can machine small shape holes, small gap or
job with complicated shape.

25.  Consumes high levels of energy
 Only able to machine conductive materials.
 More expensive process than conventional
milling or turning.

26.  Aerospace, Medical, Electronics and
Semiconductor applications
 Tool & Die making industries.
 In making Gauges & Cams
 Cutting of Gears
 Manufacturing hard Electrodes.