Electrochemical micromachining (EMM) is a non-traditional machining process that uses electrical and chemical energy for precision micro-machining of conductive materials. EMM involves anodic dissolution of workpiece material in an electrolyte solution between a tool electrode and workpiece electrode. EMM allows for machining of complex micro-scale geometries without thermal or mechanical stresses. The document describes the fundamentals, process parameters, applications and a demonstration EMM setup developed for micro-fabrication.

1. A
Seminar on
Electrochemical Micromachining
(EMM)
Presented by
Todkar Mahesh S.
M.Tech-I
Manufacturing Engineering
Under the Guidance of
Dr. A Venugopal

2. Non-Traditional Machining
Need :
• To machine newly developed metals and non-metals
• To machine complex part geometries
• To avoid surface damage

3. Classification of Non-traditional
Machining Processes
This classification is carried out depending on nature
of energy used for material removal:
Mechanical Thermo- Chemical Electro-
electric chemical
• USM • EDM • CHM • ECG
• AJM • EBM • PCM • EJD
• WJM • LBM
• AWJM • PAM
• ECM

4. Electrochemical Machining (ECM)
• Reverse of electroplating
• Work material must be a conductor
• Material removal by anodic dissolution
• Electrical energy + chemical energy

5. Electrochemical Machining (ECM)

6. Electrochemical Machining (ECM)
Advantages over other Non-conventional
Machining:
• No thermal and mechanical stresses on the workpiece
• No heat-affected layer on workpiece
• No tool wear
• Higher machining rate
• Better precision
• Controlled material removal
• Wider range of materials can be machined
• Utilized for removal and patterning of metal films and foils

7. Electrochemical Machining (ECM)
Applications:
• Die sinking
• Profiling and contouring
• Trepanning
• Micro-machining

8. Electrochemical Micro-machining (EMM)
Micromachining:
• Material removal of small dimensions
• Ranges from several microns to millimeters
• For production of miniaturized parts and components
Why Micromachining?
• Difficulties in machining of miniature components and parts
with conventional machining techniques
• Requirement of precision manufacturing

9. Electrochemical Micro-machining (EMM)
Electrochemical Micro-machining:
When electrochemical machining process is applied to
micro-machining range (i.e. from 0.1 μm to 1 mm) for
manufacturing ultra-precision shapes, it is called
electrochemical micromachining(EMM).

10. Electrochemical Micro-machining (EMM)
Fundamental Observations:
• Very small inter-electrode gap
• Rate of dissolution (machining) depends on
1. Atomic weight ‘a’
2. Valance ‘v’ of ion produced
3. Machining current ‘I’
4. Time for which current passes
• Shape of electrode remains unaltered

11. Electrochemical Micro-machining (EMM)
Metal Removal Method:
MRR =
Where, = current density,
= metal dissolution efficiency,
F = Faraday’s constant, Constant
= Density of material, for
= Valance of ion, particular
= Atomic weight of ion. operation

12. Electrochemical Micro-machining (EMM)
MRR depends on:
• Anodic reaction and Current efficiency( ),
• Mass transport effects,
• Current distribution( ) and Shape evolution.

13. Electrochemical Micro-machining (EMM)
Influence of various process characteristics:
• Nature of power supply and Machining pulse
1. DC supply
2. Pulse DC supply
• Inter-electrode gap
• Electrolyte type, Concentration and Flow
1. Passivity Electrolyte
2. Non-Passivity Electrolyte
• Size, shape and material of the Tool:

14. Electrochemical Micro-machining (EMM)
Sub-systems for EMM Setup:
• Mechanical
machine setup:
Tool-feeding block
Main machine body
Work holding device

15. Electrochemical Micro-machining (EMM)
Sub-systems for EMM Setup:
• Electrical power and control System:

16. Electrochemical Micro-machining (EMM)
Sub-systems for EMM Setup:
• Electrolyte flow
system:
Job

17. Electrochemical Micro-machining (EMM)
• Experimental EMM setup:

18. Electrochemical Micro-machining (EMM)
Specifications of EMM setup:
• Mechanical structure details:
Base: (300 * 200 * 30) mm
Vertical column: (300 * 50 * 20) mm
Main Driving screw: Φ10 * 150L, 40 TPI, 50 mm thread
Main screw nut: (25 * 50 * 40) mm, 40 TPI
Main machining chamber: (100 * 200 * 80) mm³
Bearing: 10mm bore, 10 mm Thick

19. Electrochemical Micro-machining (EMM)
Specifications of EMM setup:
• Stepper Motor Specifications:
Step angle: 1.8°
Step angle accuracy: 5%
Holding torque: 40 N-cm
Detent torque: 4 N-cm
Weight: 0.5 kg

20. Electrochemical Micro-machining (EMM)
Specifications of EMM setup:
• Pump Specifications:
Power: 0.125 HP/ 0.09 kW
Type: Centrifugal
AC: 240 V
Impeller Material: Teflon

21. Electrochemical Micro-machining (EMM)
Specifications of EMM setup:
• Microprocessor:
8085 Intel®
• Tool Specifications:
Platinum, Φ 250 μm

22. Electrochemical Micro-machining (EMM)
Applications of EMM for Micro fabrication:
• Nozzle plate for Ink Jet Printer Head
• Production of High Accuracy Holes
• 3D Micromachining

23. Electrochemical Micro-machining (EMM)
Recent Development in EMM:
• Micro Electrochemical Milling
• Wire Electrochemical Machining
• Solid Electrochemical Machining
• Oxide film laser lithography (OFLL)
• Micro and Nanometer scaled surface structuring
• Laser electrochemical micro machining (LECMM)

24. Electrochemical Micro-machining (EMM)
Conclusion:
EMM setup
• Successfully utilized
• Fulfill the requirement and the need of Micromachining
operations
Areas of modifications:
• Inter-electrode gap control feature
• Precise control of machining parameters

25. Thank you.
Any Questions?