Electrochemical machining (ECM) is a process that uses the principle of reverse electroplating, where the tool acts as the cathode and the workpiece as the anode, to remove metal atom-by-atom through an electrochemical reaction in the presence of an electrolyte. The setup requires a DC power supply, work holding system, tool feed system, and an electrolyte supply system, with notable advantages such as high tool life and burr-free surfaces, but also disadvantages like high initial investment and power consumption. ECM is mainly applied in operations like die-sinking, drilling, and turbine blade manufacturing.

1. electrochemical
MACHINING PROCESSES
S.G.R. Education Foundation
G H RAISONI COLLEGE OF ENGINEERING AND MANAGEMENT
AHMEDNAGAR
NAAC ACCREDITED
(APPROVED BY AICTE, NEW DELHI, RECOGNIZED BY GOVT. OF MAHARASHTRA & AFFILIATED TO SAVITRIBAI PHULE PUNE UNIVERSITY)
- Prof. Aniket V. Joshi
Asst. Professor
Mechanical Engineering Department
GHRCEM, A’Nagar.

2. Electrochemical machining
(ECM)
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3. PRINCIPLE OF WORKING OF ECM
o Utilizes principle of reverse electroplating
o Tool-cathode, workpiece-anode
o After electrolysis, electrolyte should not allow to decompose the
metal on tool
o Gap between tool and workpiece is maintained to 0.5 mm
o Electrolyte is continuously pumped into the gap
o Due to applied DC voltage, current flows in electrolyte
o Due to this, previously charged positive ions attracted towards
cathode and negatively charged ions attracted towards anode.
o Metal from anode is removed atom-by-atom by removing negative
charges
o Ionized atoms are then positively charged and attracted away from
the workpiece.
o Electrochemical reaction takes place in the presence of electrolyte
which results in removal of metal from workpiece
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4. Set-up of ecm
1) DC power supply unit
2) Workpiece and work holding system
3) Tool and tool feed system
4) Electrolyte supply system
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5. Set-up of ecm
1) DC power supply unit:
- current- @40,000 A
- Voltage- 5 to 30 V
2) Workpiece and work holding system:
- Workpiece- anode
- Table material is non-conductive and having good thermal
stability
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6. Set-up of ecm
3) Tool and tool feed system:
- Tool- cathode
- Small gap is maintained between tool and workpiece
- Tool feeding towards work is done by servo mechanism
- To provide passage for the electrolyte, hollow tool is used
- Tool has reverse profile of that to be produced on workpiece
4) Electrolyte supply system:
- Electrolyte is continuously pumped in to the gap between tool
and workpiece
- Electrolyte should not plate material on the tool
- When power is made ON, electrochemical reaction takes
place, which results in removal of metal from workpiece
- MRR is directly proportional to current intensity
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7. Electrochemical machining
(ECM)
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Advantages
High tool life
Burr free
surface
High MRR
Profiling and
contouring
Disadvantages
High initial
investment
High Power
consumption
Can’t produce
sharp corners and
edges
Electrically
conductive
material only
Large floor space
Applications
Die-sinking
operations
Drilling jet engine
turbine blade
Multiple hole
drilling
Steam turbine
blades

8. 8
AVJ GHRCEM AHMEDNAGAR