4. ECM Equipment
Power supply
o A low voltage (5-30V)D.C. supply is used to
provide the power for electrolyses
o The current capacity of the supply has to be large
enough to produce current density of 0.08-2.23
apm/mm at the workpiece.
o ECM machines are available with current
capacities from 50-40000 amperes to permit
machining at reasonable rates
6. Electrolyte
o The electrolyte used in the process essentially
serve three main function
1. It is necessary for the electrolysis action to take
place
2. It carries away the heat generated at the cutting
zone
3. It remove the products of the electrolysis
process such as metal particles sludge ad
evolved gases away from the cutting zone so
that electrolysis can proceed smoothly at fast
rate
7. Material Removal Process
o The erosion of work piece start at points
opposite the cathode peaks since the density of
the current is greatest in the shortest distance
between the two electrodes
o When the work piece point opposite to the
shortest distance point is eroded, the action shifts
to another/point which is now the closest till the
entire workpiece takes a shape opposite to the
shape of the tool
8. ECM Tool Design
Tool Material
o Since no wear occurs on ECM tool, any material
that is good conductor of electricity can be used
as tool.
o Commonly used tool materials include copper,
brass and stain less steel
o Other material that can be used as tool mistrials
include titanium, copper tungsten, aluminum,
graphite, tungsten carbide etc.
9. Tool design
o The design of the tool is done from two aspects
as follows:
1. Determining the theoretical shape of the tool
so that the desired shape of the tool so that
the-desired shape of the job is achieved for
the machining parameters.
2. Designing the tool from the consideration
like electrolyte flow, insulation, strength and
arrangement for fixing the tool.
o Tool are manufacture by electroforming and cold
forging methods.