A detail description of Micro machining, its classification Electro chemical micro machining Electric Discharge Micro machining micro turning their resource and application By Muhammad Mustafa memon BE Qucest larkana ME MUET jamshoro

2. P R E S E N T A T I O N B Y :
Chemical and Electro chemical micro machining,
Electric discharge micro machining, and
Micro turning
Dr. Tanveer Hussain

3. In today’s high tech engineering industries, the designer’s
requirement for the component are stringent,
 Extra ordinary properties of materials (say, high Strength, high heat
resistant)
 Complex 3D component (say, turbine blade).
 Miniature features (filters for food processing and textile industries
having a few tens of micrometer as hole diameter).
 Nano level surface finish on complex geometries (say, thousands of
turbulated cooling holes in a turbine blade)
Such features on a component can be achieved only through the
advanced manufacturing processes in general and advanced machining
processes in particular.
such as:

4. Outline
 Introduction to Micro Machining
& its Classification
 Chemical Micro Machining
 Electro Chemical Micro Machining
 Electric Discharge Micro Machining
 Micro Turning

5. Micro Machining
 Removal of material at micron level.
 Macro/Micro or Nano components but material removal is
at micro/nano level.
(Ex. MEMS, NEMS).
 Machining of micro parts is not literally correct

6. Classification

7. Chemical micro machining
 It is an ancient process being
used for engraving the metal
for making ornaments and
other products.
 It removes material in a controlled manner by the
application of maskant and etchant.
 Etchant dissolves workpiece material by chemical
action.
 Maskant does not allow etchant to reach & react
with workpiece to dissolve it.

8.  Etchant:
Purpose: to dissolve a metal by turning it into a
metallic salt, which then goes into solution
 Many chemical are available as etchants: FeCl3,
Chromic acid, FeNO3, HF, HNO3.
 Maskant or resist:
Three major categories of chemically resistant masks
are used in chemical machining
 Cut and peel, Screen printing, Photoresist masks.
Chemical micro machining

9.  Two major CHM processes are:
1. Chemical milling - eroding material to produce blind details–
pockets, channels etc.,
2. Chemical blanking – for producing details that penetrate the
material entirely (holes, slots, etc.)
 Processing steps
1. Preparing: Pre cleaning
2. Masking: Applying of chemical resistant
material (if selective etching is desired)
3. Etch: Dip or spray exposure to the etchant
4. Demasking: Strip remaining mask.
5. Finish: Inspection and post processing.
Chemical micro machining

10. Electro Chemical micro machining
 (ECM) is a non-traditional
machining process belong
-ing to Electrochemical
category.
 Electro chemical metal removal is an alternate wet
etching process.
 The work piece made an anode and the tool as
cathode in an electrolyte cell in which a non toxic
salt solution is used as an electrolyte.

11.  Controlled metal removal takes place when the
current (smooth D.C. Or Pulse D.C.) flow through
the electrolytic cell.
 Thus ECM can be thought of a controlled anodic
dissolution at atomic level of the work piece that is
electrically conductive by a shaped tool due to flow
of high current at relatively low potential difference
through an electrolyte which is quite often water
based neutral salt solution
Electro Chemical micro machining

12.  Micro-EDM is a process based on the thermoelectric
energy.
 Uses a workpiece and an electrode.
 Micro-EDM is a newly developed method to produce
micro-parts.
 In the range 50 μ m -100 μ m.
 Efficient machining process.
 Conventional EDM and Micro EDM
 Types: Sinker EDM, Wire EDM, Dry EDM
Electric Discharge micro machining

13.  Conventional EDM and Micro EDM:
Micro EDM’s principal of operating is just the same of the
conventional EDM but the usage of small electrode size and
micro scale MRR are the only difference.
 The Electrodes:
conventional EDM and Micro EDM electrodes are usually
made of graphite, brass and copper.
 These electrodes that used as tools for the machine are
basically shaped by forming, casting, powder metallurgy or
CNC machining technique.
 The diameter of the electrodes sometimes as small as 0.1 mm.
these electrodes are used to produce depth to hole diameter
ratios of up to 400:1.
Electric Discharge micro machining

14.  Process:
A pulse discharges occur in a small gap between the work piece and the
electrode and at the same time removes the unwanted material from the
parent metal through the process of melting and vaporization.
Electric Discharge micro machining

15. Micro Turning
 Micro turning is one of micromachining process which
uses a solid tool and its material removal process to micron
level in a turning operation.
 Used to create micro cylinderical or rotational smmetry
parts by cutting away unwanted material.
 Requires a turning machine, workpiece, fixture, and
cutting tool.
 Bridges the gap between MEMS manufacturing and the
capabilities of conventional machining.
Fig. Shows example of
simple micro pin

16. Micro Turning
 Material removal process is similar to conventional
turning
 Weather its Macro/Micro turning.!
 Range not exactly differentiated but mostly referred
as: 0.5μm-999μm, Some reseachers suggest:
500μm-999μm
J. Mc Geough,
0.5μm-499 μm
Alberto Herrero
a) Micro Cutting process b) Micro turned shaft
Fig. Shows example of simple micro pin with diameter of
33μmeters

17. - Imam Ali (a.s)
Thank You
 if you have any Question………….?