IRJET- Modeling and Design Analysis of Die Profile of Extrusion of Square Section from Round Billet through Non-Linear Converging Dies

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 06 Issue: 07 | July 2019 www.irjet.net p-ISSN: 2395-0072
© 2019, IRJET | Impact Factor value: 7.211 | ISO 9001:2008 Certified Journal | Page 1702
Modeling and Design Analysis of Die Profile of Extrusion of
Square Section from Round Billet through Non-linear
Converging Dies
V. JAGADEESH1 and M. RAMA NARASIMHA REDDY2
1Student, M.Tech, Mechanical Dept., SVTM, Madanapalle, A.P, India
2Associate Professor, Mechanical Dept., SVTM, Madanapalle, A.P, India
-----------------------------------------------------------------------***------------------------------------------------------------------------
Abstract: A non-linear converging die profile for
extrusion of square section from round billet was
designed using cosine function. MATLAB 7.1 was used
to find out the co-ordinates of the cosine die profile. A
solid model was generated using AutoCAD 2008 from
the above generated points. The STL files of extrusion
die generated in AutoCAD was used in DEFORM-3D for
FEM simulation. Experimental investigation of
extrusion of square section from round billet using
non-linear converging dies were done for different
percentage of reduction of cross section in dry and
lubricated condition. All the experiments were done
using FIE‟ Electronic Universal Testing machine (UTM),
model UTS-100 with maximum capacity of 1000 kN
with accuracy ±1.0% kN. Material properties of lead
like flow stress and friction factor were determined
using compression and ring compression tests under
different boundary conditions. To study the flow
pattern of the material during extrusion, experiments
were done with split work piece in lubricated condition
by making grid. The extrusion load with punch travel
was compared with extrusion load with solid work
piece under same experimental condition. It was found
that extrusion load in splitted work piece is less than
the work piece when solid. FEM simulation of extrusion
of square section from round billet for pure Lead and
aluminium-1100 as work material were done using
DEFORM-3D 6.1 (sp1). For FEM simulation the linear
converging and cosine (non-linear converging) die
profiles are used. FEM simulation using leads were
done for two frictional conditions 0.38 and 0.75
corresponding to dry and lubricated conditions.
Extrusion was assumed to be isothermal. From present
investigation it was found that the extrusion load in
case of cosine (non-linear converging) die is less than
the linear converging dies under same condition. The
extrusion load increases with increase in reduction and
friction factor.
Definition of Extrusion:
Extrusion can be defined as the process of subjecting a
material to compression so that it is forced to flow
through a confined space past a suitable opening called
the die. The metal is forced through the die and the
cross-section of the die determines the shape
properties of the resulting product. Extrusion may be
done either on cold metal or on heated metal. One of
the analogies that can be offered to the process of
extrusion is that of squeezing a tube of toothpaste. The
metal billet is placed in the billet chamber and is forced
by the ram through a die.
Hot extrusion is done to eliminate the cold working
effects, reduce the force required, and reduce
directional properties. However cold extrusion is also
possible for many metals and has become an important
commercial process. The reaction of the billet with the
container and the die results in high compressive
stresses that effectively reduce cracking of materials
during primary breakdown from ingot. This is an
important reason for increased commercial adoption of
extrusion in the working of metals difficult to form
such as stainless steel, nickel, nickel based alloys and
other high temperature materials. Lead, brass, bronze,
copper, aluminum, and some of the magnesium alloys
are the most commonly extruded metals.
In general extrusion is used to produce cylindrical bars
or hollow tubes. A large variety of irregular cross
sections are also produced by this process using dies of
complex shapes. The process has definite advantage
over rolling for production of complicated section
having re-entrant corners. In this process large
reduction achieved even at high strain rates has made
it one of the fastest growing metal working methods.

Classification of Extrusion
According to the flow direction of metal with respect to
ram movement direction extrusion process can be
classified under the following methods
Direct extrusion
Indirect extrusion
Impact extrusion
Direct Extrusion
Direct extrusion is a process where the flow of material
through the die is in the direction of the movement of
the ram that is used to force the material. Here the
billet is moved forward relative to the wall of the
container, thereby giving rise to high resistance from
friction.
Indirect Extrusion
Indirect extrusion is a process where the flow of the
material through the die is in a direction opposite to
the movement of the ram that is forcing the material to
deform. Here there is no relative motion between the
container and the billet and, therefore, the frictional
force is minimal.
Impact Extrusion
Impact extrusion is a process where a single blow from
the ram on the material causes the metal billet to be
extruded between the die and the punch. This process
is usually done cold and on low strength ductile
materials such as lead, tin and aluminum. It is used to
make collapsible tubes for toothpaste, shaving cream,
and cans that are used to pack food.
Die Design Consideration
For die design of extrusion following factors are to be
considered as given bellow.
 Desired shape of the product
 Material
 Billet size
 Process capacity
 Extrusion ratio
 Number of die cavities
 Shrink factor
 Process tool
 Extrusion temperature
 Extrusion pressure
 Die material
 Heat treatment of die material
Advantages of Extrusion
Among the different metal forming processes,
extrusion has definite advantages over others for the
production of three dimensional section shapes. Now it
is becoming essential to pay greater attention to the
extrusion of section rod from round stock, as this
operation offers the promises of an economic
production route. The process is also attractive because
press machines are readily available and the necessity
to purchase expensive section stock corresponding to a
multiplicity of required sections is eliminated. There
are many advantage of extrusion as follows
 Uniform cross-sectional area over a long length.
 Low cost of dies making it economical to make
small quantities of a shape.
 Good surface finish.
 Strain and hardness are increased due to strain
hardening
Limitations of Extrusion
 Every process has some limitation; extrusion has
also some limitation as given bellow
 Most materials require high temperature and
pressure, which makes the equipment costly.
 Die material should be able to withstand the load,
high temperature, and wear.
 In the case of steel, the equipment is costlier due
to the magnitude of temperature to which the
metal must be heated. (2300 F).
 Indirect extrusion complicates the handling of
the extruded parts.
 Extrusion is limited to only a few metals and
cannot be done on any metal chosen.
Applications of Extrusion
Extrusion is one of the most important methods of
metal forming process with we can produce many
product of high industrial applications with good

quality. Some of the applications of the extrusion
process are given bellow
 Helicopter blades
 Turbine blades
 Wingspans
 Columns used for creating structures
 Construction material
Upper Bound Solution
An upper bound analysis provides an overestimation of
the required deformation force. It is more accurate
because it will always result in an overestimation of the
load that the press or the machine will be called upon
to deliver. In this case factor of safety will be
automatically built in. In this analysis, the deformation
is assumed to take place by rigid body movement of
triangular blocks in which all particles in a given
element moves with the some velocity.
A kinematically admissible velocity should satisfy the
 Continuity equation
 Velocity boundary condition
 Volume constancy condition
The power of deformation calculated from this is
higher than the actual one, called upper bound. When
applying upper bound, the first step is to conceive of a
velocity field for the deforming body.
 The field can be easily imagined and related to our
visual experience.
 Velocity can be measured directly and is easily
displayed in a physical manner.
 In this case factor of safety is automatically in built
 It is comparatively easy to analyze.
 There exists an infinite no stress field that satisfy
the upper bound solution.
Finite Element Analysis
The finite element analysis method represents an
extension of matrix method for the analysis of framed
structures to the analysis of the continuum structure.
The basic philosophy of this method is to replace the
structure i.e. the continuum having an infinite or
unlimited number of unknowns by a mathematical
model, which has a limited or finite number of
unknowns at certain chosen discrete points. This
method is extremely powerful as it helps to accurately
analyze structures with complex geometrical
properties and loading condition.
In finite element method, a structure or a continuum is
discredited and idealized by using a mathematical
model, which is an assembly or subdivision or discrete
elements. These elements known as finite elements are
assumed to be interconnected only at the joints called
nodes. Simple functions such as polynomials are
chosen in terms of unknown displacements and or
their derivative at the nodes to the approximate over
the variation of the actual displacements over each
finite element. The external loading is also transformed
into equivalent forces applied at the nodes. The
behavior of each element and later as an assembly of
these elements is obtained by relating their response to
that of the nodes in such way that the following basic
conditions are satisfied at each node.
 The equation of equilibrium.
 The compatibility of displacements.
 The material constitutive relationship.
The equation, which are obtained using above
condition and then these modified equations are solved
to obtain displacements at the nodes, which are the
basic unknowns of the finite element method. Finite
element method involves extensive computations
mostly repetitive in nature. Hence, this method is
suitable for computer programming and solutions.
Finite element computer programs have become
widely available, easier to use and can display results
with attractive graphics. Even an inept user can
produce some kind of answer. It is hard to disbelieve
finite element results because of the effort needed to
get them and the polish of this presentation. However,
smooth and colorful stress contours can be produced
by any model, good or bad. It is possible that most
finite element analyses are so flawed that they cannot
be trusted. Even a poor mesh, improper element type,
incorrect loads or improper supports may produce
results that appear reasonable in causal inspection.
Experimental Investigation
The whole experimental investigation were done using
„FIE‟ Electronic Universal Testing machine (UTM),

model UTS-100 which can be used for conduction test
in tension, compression and transverse test of metals
and other material. Maximum capacity of the machine
is of 1000 kN with measuring range between 0 to 1000
kN. The accuracy of measurement of the machine is
±1.0% kN Because load required for extrusion is of
compressive type so, experiments were conducted
using compression test.
‘FIE’ Electronic Universal Testing machine (UTM)
The UTM consists of three major parts
 Machine frame or Loading unit
 Hydraulic system
 Electronic control panel
Machine frame or Loading unit
Machine frame and loading unit consist of two cross
heads and one lower table. Center cross head are
adjustable by means of geared motor. Compression test
is carried out between center and lower table while
tension test is carried out between center table and
upper cross head. Load is sensed by means of precision
pressure transducer of strain gauge type
Hydraulic System unit
Hydraulic system unit consists of motor pump unit
with cylinder and piston. Safety valve is provided for
additional safety.
Electronic control unit
Electronic control unit control the process by
controlling the input parameter like load rate, strain
rate, maximum load etc.
Selection of the work-piece
The selection of material depends upon the properties
of die material and load required for deformation.
Because load required for extrusion is very high so we
had to select softer materials, so we select lead as
workpiece material of experimental investigation. Lead
is a highly dense, corrosion resistive and very soft
ductile material. Properties of lead in detail are given in
table.
Mechanical properties of lead
Thermal Properties
Compression test
Pure lead cylinders with a 50mm × 30 mm (H× D) were
taken to obtain the stress-strain curve by a
compression test using „FIE‟ Electronic Universal
Testing machine (UTM), model UTS-100 at room
temperature. The compression rate is maintained same
as that adapted for the experiments. The specimen has
oil grooves on both the ends to entrap lubricant during
the compression test. The compression load is
recorded at every 0.5 mm of punch ravel. After
compressing the specimen to about 10 mm it is taken
out of the press. Compressed material re-machined to
cylindrical shape with original diameter, and tested in
compression till the specimen is reduced to another 10
mm. The stress-strain diagram was drawn. The average
flow stress of the pure lead is found to be 48.85
N/mm2

Ring Compression Test
A ring compression test was carried out at dry
condition and commercially available grease
lubrication condition. The rings were compressed up to
the 4 mm inner diameter, at each 0.5 mm of punch
travel inner diameter and height was recorded. The
friction factors were found to be 0.75 for dry condition
and 0.38 for the lubricated condition by comparing our
result with the calibration curve of Male and Cockcroft
as shown in the fig.
Experimental procedure
Before starting the test the die sets, die holder and
inside face of extrusion chamber were cleaned. The two
halves of the die set were then push fitted into die
holder and total assembly were secured by screwing
four bolts. The full assembly was then placed in
between the base plate and center table of „FIE‟
Electronic Universal Testing machine (UTM), model
UTS-100 in upside down position. It was done so that
extrude product would get enough clearance, when it
comes out from the die. For carrying out an extrusion
test the pure lead specimen was placed inside the
extrusion chamber or container. The punch was then
inserted into its position. After centering the apparatus
under machine lower table, Machine was started and
extrusion process was continued. Punch load was
recorded at every 1 mm movement of punch travel,
which was read from computer fitted to the UTM. The
application of load was continued till it reaches the
steady state and up to certain length of product comes
out side. At this position Machine was stopped and test
was terminated the die holder was then separated from
extrusion chamber and finally die halves with extruded
product were pushed out from die holder and
extrusion chamber. Experiments were conducted for
three different reductions 50%, 70% and 90% to get
square section product at two different experimental
conditions (dry and lubricated) from round cross-
section billet.
Split Test
Lead material round billet of 30mm diameter and
50mm length is taken as work material, the work
material is spited in to two parts along it diameter. A
grid of 5mm x 5mm is made in to inner surface of the
slitted part. In fig 5 grid pattern is shown. Rubber band
is put in to the grid pattern to prevent material mixing
during extrusion, because lead is a very soft ductile
metal. Now, both part are again join using araldite
(gum) and clamp it for 48 hour so that both part joined
properly like single piece.
Extrusion is carried out in lubricated condition of split
work material. The flow pattern is studied for different
percentage of reduction. Work material after extrusion
with 50% reduction is shown in fig 6. In fig 7 flow
pattern of material with 70% reduction in area is
shown. Fig 8 shows the flow pattern of material with
90% reduction.
Finite element analysis
Finite element analysis modeling is done using
DEFORM-3D Version 6.1(sp1). DEFORM-3D is a Finite
Element Method (FEM) based process simulation
system designed to analyze various forming and heat
treatment processes. By simulating manufacturing
processes on a computer, this advanced tool allows
designers and engineers to:
 Reduce the need for costly shop floor trials and
redesign of tooling and processes
 Improve tool and die design to reduce production
and material costs
 Shorten lead time in bringing a new product to
market.
Unlike general purpose FEM codes, DEFORM is tailored
for deformation modelling. A user friendly graphical
user interface provides easy data preparation and

analysis so engineers can focus on forming, not on
learning a cumbersome computer system.
The DEFORM-3D consists of three major components:
 Pre-processor: used for creating assembly or
modifying the data required to analyze the
simulation, generating mesh and for generating the
required database file.
 Simulation engine: Used for performing the
numerical calculations required to analyze the
process, and writing the results to the database file.
The simulation engine reads the database file,
performs the actual solution calculation, and
appends the appropriate solution data to the
database file.
 Post-processor: Used for reading the database file
from the simulation engine and displaying the
results graphically and for extracting numerical
data.
Solid Modelling
MATLAB 7.1 was used to generate the no fo points
using above generated die profile equation. The
generated points were used to create solid model using
AutoCAD 2008. Solid model generated from AutoCAD
2008 were shown in the following figures
Dual stream function :
General equation of any point on the cross-section
using cosine function will be given by the equation (1)
and (2)
Let the stream function are
Now Ѵx, Ѵy, Ѵz are velocity
function in x, y &z direction
respectively. Then velocity
field in x, y and Z direction
can be given as follows.
Derivation of kinematically admissible velocity
field
Using equation (1) & (2) velocity function can be
written as follow

Derivation of strain function
Now Ԑxx ,Ԑyy, Ԑzz strain function in x, y & z direction
respectively.
Using equation (1) & (2) strain function can be written
as follow
Adding equation (1), (2) & (3) we get
Results and Discussions:
Experimental Investigation
Comparison of extrusion load with punch travel in dry
and lubricated condition for 50% reduction
condition for different reduction

Comparison of extrusion load with punch travel in
lubricated condition for solid and split die with 50%
reduction
reduction
reduction
FEM simulation of Alluminium-1100:
FEM Simulation using aluminum-1100 as work
material was done with non-linear converging die
(cosine die) and linear converging die. It is found that
the extrusion load is less in case of cosine die as shown
in fig.32. Some properties like effective stress, velocity
and principal stress at last step are shown in fig
lubricated condition with cosine and taper die
Effective stress, principal stress and velocity field at last
step of extrusion
FEM simulation of pure lead:
FEM simulation using lead was done for two frictional
conditions 0.38 and 0.75 as derived from experiment
using ring compression test. Extrusion load with punch
travel for friction factor m=0.38 and m= 0.75 are shown
in fig
Extrusion load with punch travel for dry and lubricated
condition using cosine die

Principal stress and velocity field at last step of
extrusion
CONCLUSIONS:
A non-linear converging die profile has been designed
for extrusion of square section from round billet using
cosine function.
 The extrusion load increases with increase in
reduction and friction factor.
 Load in case of split test is less as compared to solid
work material under same experimental condition.
 The extrusion load for non-linear converging die is
less as compared to linear converging die under
same simulation condition.
 The flow of material in non-linear converging die
appears to be gradual specially in higher reduction.
REFERENCES:
1. S.K. Sahoo, P.K. Kar, K.C. Singh, A numerical
application of the upper-bound technique for
round-to-hexagon extrusion through linearly
converging dies, Journal of Materials Processing
Technology 91 (1999) 105–110
2. S.K. Sahoo, P.K. Kar, K.C. Singh, Upper-bound
analysis of the extrusion of a bar of channel section
from square/rectangular billets through square
dies, Journal of Materials Processing Technology 75
(1998) 75–80
3. K.P. Maity, P.K. Kar, N.S. Das, A class of upper-
bound solutions for the extrusion of square
Shapes from square billets through curved dies,
Journal of Materials Processing Technology 62
(1996) 185- 190
4. R. Narayanasamy, R. Ponalagusamy, R. Venkatesan,
P. Srinivasan, An upper bound solution to extrusion
of circular billet to circular shape through cosine
dies, Materials and Design 27 (2006) 411–415
5. R.K. Sahoo, P.K. Kar, S.K. Sahoo, 3D upper-bound
modeling for round-to-triangle section extrusion
using the SERR technique, Journal of Materials
Processing Technology 138 (2003) 499–504
6. B.S. Altan, G. Purcek, I. Miskioglu, An upper-bound
analysis for equal-channel angular extrusion,
Journal of Materials Processing Technology 168
(2005) 137–146
7. J.S. Ajiboye, M.B. Adeyemi , Upper bound analysis of
die land length in cold extrusion, Journal of
Materials Processing Technology 177 (2006) 608–
611
8. M.H. Paydara, M. Reihaniana, R. Ebrahimia, T.A.
Deanb, M.M. Moshksara, An upper-bound approach
for equal channel angular extrusion with circular
cross-section, journal of materials processing
technology 198 (2008) 48–53
9. D.K. Kim, J.R. Cho, W.B. Bae, Y.H. Kim, Upper-bound
analysis of square-die forward extrusion, Journal of
Materials Processing Technology 62 (1996) 242 -
248
10. S.K. Sahoo, Comparison of SERR analysis in
extrusion with experiment, Journal of Materials
Processing Technology 103 (2000) 293-303
11. Y.H. Kim, J.R. Choa, K.S. Kim, H.S. Jeong, S.S. Yoon, A
study of the application of upper bound method to
the CONFORM process, Journal of Materials
Processing Technology 97 (2000) 153-157
12. W.A. Gordon, C.J. Van Tyne, Y.H. Moon, Overview of
adaptable die design for extrusions, Journal of
Materials Processing Technology 187–188 (2007)
662–667
13. N. Venkata Reddy, R. Sethurama, G.K. Lal, Upper-
bound and finite-element analysis of axisymmetric
hot extrusion, Journal of Materials Processing
Technology 57 (1996) 14 22
14. M.K. Sinha, S. Deb, U.S. Dixit, Design of a multi-hole
extrusion process, Materials and Design 30 (2009)
330–334

15. W. Johnson, Experiments in the cold extrusion of
rods of non-circular sections, Journal of Mechanics
and Physics of Solids 7 (1958) 37-44.
16. K. P. Maity, A. K. Rout, Kalu Majhi, computer-aided
simulation of metal flow through curved die for
extrusion of square section from square billet ,
Presented in International Conference on Extrusion
and Benchmark, Dortmund, Germany, 16-17
September, 2009
17. B.B. Basily, D.H. Sansome, Some theoretical
considerations for the direct drawing of section rod
from round bar, Int. J. Mech. Sci. 18 (1979) 201–
209
18. V. Nagpal, T. Altan, Analysis of the three-
dimensional metal flow in extrusion of shapes.

IRJET- Modeling and Design Analysis of Die Profile of Extrusion of Square Section from Round Billet through Non-Linear Converging Dies

More Related Content

What's hot (20)

Similar to IRJET- Modeling and Design Analysis of Die Profile of Extrusion of Square Section from Round Billet through Non-Linear Converging Dies (20)

More from IRJET Journal (20)

Recently uploaded (20)

IRJET- Modeling and Design Analysis of Die Profile of Extrusion of Square Section from Round Billet through Non-Linear Converging Dies