Traditional machining of Inconel 718 generates residual stresses and lower surface quality compared to non-traditional machining. Non-traditional methods like EDM and laser machining produce better surface integrity with minimal damage. The document reviews different studies on optimizing machining parameters for conventional turning and EDM of Inconel 718 to maximize material removal rate while minimizing surface roughness and recast layer thickness.

1. STUDY OF TRADITIONAL AND NON
TRADITIONAL MACHINING OF
INCONEL718
Under Guidance of:- MR. Rakesh Chaudhari
Made By:- Parth Dasadiya
(14BME133D)

2. Introduction
• In the Traditional or conventional machining process,
machine tools such as lathes, milling machines, drill pressure
or others are used with sharp cutting tool to remove material
to achieve a desired geometry
• In traditional machining, tool is required harder than the work
piece
• Non traditional machining may not be a present physical tool
like EDM,EDM wire cut, ECM, and micro EDM
• In non traditional machining tool is not required harder than
the workpiece

3. Why Inconel
• Inconel is a family of austenitic nickel(50%)-chromium(21%)-
based super alloys. Inconel alloys are typically used in high
temperature applications.
• High Resistance to wear and corrosion and high creep
strength at elevated temperatures.
• Inconel-800,825,600,625,601,718 etc.
Density:0.305 lb/inch3
Melting Range:2350-2460°F
Ultimate Tensile Strength:120 ksi
Ref:- google .com / inconel photos

4. Convectional Non-convectional
Speed Current
Feed Voltage
Depth of cut Wire tension
Wire feed
Gap between tool and work-
piece
Time
Parameter

5. Applications of Inconel 718
Ref:- google.com/ inconel+photos&safe
• Inconel718 is a candidate material for Aerospace application
• Jet engine
• Gas turbine operation
• Tesla is now using Inconel 718 place of steel
• Turbine wheel in turbo charger
• blackbox recorders on aircraft
• Fir Tree slot Production

6. Methodology
Convectional Non-convectional
Selecting suitable machining in
which parameters are optimized.
Checking Parameters like
Speed, feed, depth of
cut
Checking Parameters like finishing
time, pulse off time ,gap between
electrode and work piece etc.

7. Testing
Mechanical Metallurgical
Surface roughness Optical microscopy
Hardness EBSD(Electron back scatter diffraction)
Tensile testing Residual stress by XRD(X-ray Diffraction)
TEM(Transmission electron microscopy)

8. Taguchi Method
• Taguchi Method is a statistical approach to optimize the process
parameters and improve the quality of components that are
manufactured.
• Taguchi’s Method of parameter design can be performed with
lesser number of experimentations as compared to that of full
factorial analysis and yields similar results.
• It is found that the parameter design of the Taguchi method
provides a simple, systematic, and efficient methodology for
optimizing the process parameters.
Ref:1

9. literature Review
Sr.n
o
Researcher & Year Title Remark
1 G.K. Padhy 2016 Progress toward improvement
in surface integrity of
inconel718 under high pressure
and flood cooling condition
• Good surface integrity can be achieved by
proper selection of machining parameter
• Coolant type ,pressure and direction
maintain suitable compromise between
resulting surface
• Dry machining does not beneficial for the
machining for the inconel718.
• flood cooling provide better cooling effect
with lower degrees of surface roughness
2 M.P Jahan 2016 Study on operating parameters
during the micro-electro-
discharge m/c of NI based alloy
• As the m/c time is reduce discharge energy
is increase
• High tool rotation is more efficient with low
tool rotation
• Tool wear reduce with increasing discharge
energy due to the reduced tool contact
machining time of tool
3 V Thomson 2010 Laser assisted high –speed
finish turning of super alloy
Inconel 718 under dry
condition
• Using laser assisted method surface finish
improve 25% and material removal rate is
increased 800%
• Improve machinability through softening
material and reduce tool wear

10. Sr.no Researcher & Year Title Remark
4 Han-ming chow 1998 Study of added powder in kerosene
for the micro-slit machining of alloy
using EDM
● Al and sic use with dielectric fluid
kerosene.
● When kerosene and al powder use
conductivity increase, gap increase
and we get minimum wear
5 Jonas Holmberg 2016 Grit blasting for removal of recast
layer from EDM process on
inconel718 shaft
● Grit blasting is possible method to
remove RCL after EDM processing
● penetration depth and amplitude of
the compressive stresses increase
with shorter nozzle distance
6 Luca Iuliano 2016 influence of electrode size and
geometry in electro-discharge
drilling of inconel718
● process performance in terms of
productivity,tool wear, and surface
roughness are measured versus pulse
power on varying electrode size and
geometry providing
7 J Bonny 2004 effect of high pressure coolant
supply when machining nickel-base
,inconel718 ,alloy with coated
carbide tools
● machining with coated carbide tool
under high-pressure coolant supplies
can improve tool life up to 7-fold,
especially at higher speed condition
● 203bar coolant pressure produce well
segmented c-shape chips.

11. Sr.no Researcher & Year Title Remark
8 D Welling 2014 Surface Integrity and Fatigue
Study of Wire-EDM
compared to Broaching and
Grinding for demanding Jet
Engine Components made of
Inconel 718
● high cycle fatigue life show for the
broached and wire EDM w/p failure
moments in same magnitude
● especially for the manufacturing
demanding production of fir tree slot
research that wire-EDM is
alternative to the broaching process
in terms of the component strength
9 D.K Aspinwall 2008 Workpiece surface roughness
and integrity after WEDM of Ti–
6Al–4V and
Inconel 718 using minimum
damage generator technology
● extremely low level of workpiece
damage using WEDM Technology
● WEDM system are suited 24hr
operation where recast material was
evident, this was at a very low
thickness which could be removed
etching etc.
10 Thomas R. Newton 2009 Investigation of the effect of
process parameters on the
formation and
characteristics of recast layer in
wire-EDM of Inconel 718
● A surface roughness which increases
mainly with energy per spark, and
slightly with wire diameter.
● Average recast layer thickness was
generally between 5 and 9micronm.
● Table feed rate indirectly influenced
Tensile in-plane surface residual
stresses which decrease with
increasing energy per spark.

12. literature Review
Surface roughness
in terms of S/N
ratio
Higher S/N ratio
indicate better
surface roughness
Ref:-G.K. Padhy 2016, Progress toward improvement in surface integrity of inconel718 under high pressure and flood cooling condition

13. Summary
• Surface roughness achieve in conventional method by selecting optimal
process parameter is not as good as that of obtained from non-
conventional machining.
• During the machining process, residual stresses are generated in the
machine component due to severe plastic deformation in conventional
machining methods
• MRR is higher in conventional machining with increase in the surface
roughness.

14. References
1. Dr.Y.D Venkatesh, International Refereed Journal of Engineering and Science (IRJES).
2. Han-ming chow 1998,Elsevier, Surface integrity characteristics in wire-EDM of inconel 718 at
different discharge energy,page-12
3. Jonas Holmberg 2016,Elsevier, Investigation of the effect of process parameters on the formation and
characteristics of recast layer in wire-EDM of Inconel 718
4. Luca Iuliano 2016, Springer, A review on the progress towards improvement in surface integrity of
Inconel 718 under high pressure and flood cooling conditions
5. J Bonny 2004, Elsevier, effect of high pressure coolant supply when machining nickel-base ,inconel718
,alloy with coated carbide tools ,page-22
6. G.K. Padhy 2016, Elsevier, Progress toward improvement in surface integrity of inconel718 under high
pressure and flood cooling condition,page-12-34
7. M.P Jahan 2016,Elsevier, Study on operating parameters during the micro-electro-discharge m/c of NI
based alloy
8. V Thomson 2010,Elsevier, Laser assisted high –speed finish turning of super alloy Inconel 718 under dry
condition,page-1-20
9. D Welling 2014,Springer, Surface Integrity and Fatigue Study of Wire-EDM
compared to Broaching and Grinding for demanding Jet Engine Components made of Inconel 718
10. Thomas R. Newton 2009 ,Elsevier, Investigation of the effect of process parameters on the formatio
and characteristics of recast layer in wire-EDM of Inconel 718,page-62-75
11. D.K Aspinwall 2008,Elsiever, Workpiece surface roughness and integrity after WEDM of Ti–6Al–4V and
Inconel 718 using minimum damage generator technology,page-45-65