ELECTROCHEMICAL GRINDING

1. BIRLA VISHVAKARMA MAHAVIDYALAYA
TOPIC: ECG – Electro Chemical Grinding
Guided by: PROF. A H JARIYA
Presented By:
SR.NO. ENROLLMENT NO. NAME
1 140080125002 ULLAS BHALANI
2 140070125028 VRAJ SHAH
SUBJECT: ALLIED MANUFACTURING TECHNOLOGY (2162507)

2. Why non traditional process
required??
 Unconventional manufacturing processes is defined as a group
of processes that remove excess material by various techniques
involving mechanical, thermal, electrical or chemical energy or
combinations of these energies but do not use a sharp cutting
tools as it needs to be used for traditional manufacturing
processes.
 Extremely hard and brittle materials are difficult to machine by
traditional machining processes such as turning, drilling,
shaping and milling.

3.  Several types of non-traditional machining processes have been
developed to meet extra required machining conditions. When these
processes are employed properly, they offer many advantages over
non-traditional machining processes
 Unconventional process is employed where traditional machining
processes are not feasible, satisfactory or economical due to special
reasons as discussed below….
• Very hard fragile materials difficult to clamp for traditional
machining
• When the workpiece is too flexible or slender
• When the shape of the part is too complex

4. What is ECG??
• Electrochemical grinding is a process that removes electrically
conductive material by grinding with a negatively
charged abrasive grinding wheel, an electrolyte fluid, and a
positively charged workpiece.
• Materials removed from the workpiece stay in the electrolyte
fluid. Electrochemical grinding is similar to electrochemical
machining but uses a wheel instead of a tool shaped like the
contour of the workpiece.

5. •In this process the abrasive
lead and grinding field is
connected to cathode
and the work piece is connected
to the anode

6. What Process characteristics
required??
• The wheels and workpiece are electrically conductive.
• Wheels used last for many grindings - typically 90% of the
metal is removed by electrolysis and 10% from the abrasive
grinding wheel.
• Capable of producing smooth edges without the burrs caused by
mechanical grinding.
• Does not produce appreciable heat that would distort workpiece.
• Decomposes the workpiece and deposits them into the
electrolyte solution.

7. Process parameters governing MRR
• Type of abrasive, grain size, grain concentration, profile of the
grinding wheel and bonding material used.
• Shape of work material, pre-treatment process involved and
surface topography and
• Machining conditions such as feed rate, wheel speed, depth of
cut etc.
• Input voltage across the two electrodes
• Equivalence of atomic weight and valency of elements of work
material
• Conductivity and strength of electrolyte
• Gap width
• Degree of polarization

8. Advantages
 Can grind thin material of 1.02 mm, which normally warp by the
heat and pressure of the conventional grinding
 Burr free
 No work hardening
 Stress free
 Better finish
 No cracking
 Less frequent wheel dressing
 No metallurgical damage from heat
 Faster for tough materials
 No wheel loading or glazing
 More precise tolerances up to 0.025mm

9. Limitations
• Both the work piece and the grinding wheel must be conductive.
• It is only applicable to surface grinding.
• The electrolytic fluid can cause corrosion at the work piece and
grinding wheel surfaces.
• More complicated than traditional machining methods.
• Higher production cost.

10. Applications
• Grinding turbine blades
• Grinding honeycomb metals for aerospace application
• Sharpening hypodermic needles
• Machining carbide cutting-tool inserts
• ECG is used to remove surface defects from parts where
excessive material removal and residual stresses are undesired,
such as re-profiling locomotive gears
• Removal of fatigue cracks from underwater steel structures. In
this case, seawater itself acts as the electrolyte. Diamond
particles in the grinding wheel remove any non-conducting
organic matter, such as algae, before electrochemical grinding
begins.