SUBMITTED TO : RESEARCH ASSISTANT MAHMUT FURKAN KALKAN
SUBMITTED BY: RÜZGAR GÖKTUĞ ULAŞ
STUDENT ID:210102011080
DUE DATE: 13 . 11 .2023
PURPOSE
In this test we measured the gauge lenght and final and initial
diameter of specimen. Then test machine prepared for specimen and
our specimen gripped on the machine for apply load while turning on
the handle of the machine and then we noted our data .
INTRODUCTİON
Substantial amount of material are available in engineering
application. When we make a design we have to choose most suitable
material, but how we suppose to know the best correct material we
choose, firstly we need compare the materials as far as concern
mechanical properties. And collect the data their mechanical
behaviour. Such type of data are going to provide by mechanical test.
Among the tests, we will discuss with the tensile test.
Elastic Behavior: Elastic behavior refers to the property of a
material to return to its initial shape when external forces, such as
pushing or pulling, are no longer applied. When this ability finishes, it
is referred to as the "elastic limit" of the material.
Plastic Behavior: Once the elastic limit is exceeded and additional
weight is applied to the material, it fails to revert to its initial shape
upon cut out off the force. A portion of the deformation becomes
permanent, resulting in a permanent alteration of the material's
dimensions. In simple terms, the material undergoes deformation and
is incapable to recover its original shape.
TENSİLE TEST PROCEDURE
What is the tensile test:
Tensile test are going to provide us to easiest type of to evaluate
material properties such as defining yield strenght, tensile strength and
ductility of material. And also defining the condition of main stress
that are reasons of failure.
How we apply to procedure of this test: we have to take correct test
specimen ,before the test we have to make some measurement on
specimen for example gauge length, diameter of specimen.
And then place specimen on testing machine (we have to sure griping
should be consistly to strict among of the grip head other wise
material can be suddenly thrown and can damage to the machine.)
And then we can apply to load on specimen starting from zero and
increasing gradually while turning the handle of machine. After all
provided data base from this test we can easly draw graph:
Firstly we can graph load and elongation graph with our data and
then draw stress- strain diagram.
DEFINITIONS
Stress ( engineering stress ): The force applied to specimen
divides by
undeformed area.

Ultimate Strength(tensile strenght): Maximun stress the material
can resist while being streching or pulled before breaking point.
 Fmax/A
Fracture Stress:
While applying tensile test on material, the stress at which specimen
break down beacuse of fracture.
 Ffracture/A
Strain (Engineering Strain) : Its means the the external awerable
change of the shape of material because of the appliyed force on
specimen.

Ultimate Strain: That means its maximum point on stress strain
curve. After that point material can be break down.
 ΔL max / A0
Fracture Strain ( Elongation At Break Point):
The ratio between final length and initial length after break point of
test material.
 ((final gage length – initial gage length)/ initial gage length) x 100.)
True Stress: Is the stress calculated from current load applyed to the
original cross sectional area of the material.
True Strain: Its means change in gauge length with respect to the
instant length.
YOUNG'S Modulus - Modulus Of Elasticity:
It means that how much a material streches or compresses when you
push or pull on it amenably , as long a s we dont push too hard change
how it act , we have to know that in stress strain diagram in elastic
region , for linearly elastic materials slope is should be constant , so
we can understand that greater is the slope, much stiffer the material.
Toughness (T0): Toughness relates to a material's ability to absorb
energy when subjected to bending or stretching forces.
Resilience: Resilience indicate that a material's capacity to return to
its original shape after experiencing bending or stretching
Resilience = 1/2 yield point of elongation * yield point of force
FORCE
(kg)
F-ΔL GRAPH
1800
1600
1400
1200
1000
800
600
400
200
0
0
1
2
3
4
5
6
7
8
ΔL (mm)
CALCULATIONS OF FORCE-ELONGATION GRAPH
Resilliance: ½ Fy*DLy: ½ *1579 * 0,51 = 402.64 kg*mm
T0=Fut*DLut: 1692,25 * 6.61= 11185.77kg*mm
A0= pi/4 * D0 KARESİ= 3.14/4 * 12^2 = 113.04 mm^2
Yield Point
Stress (σ)
Stress-Strain Graph
16
14
12
10
8
6
4
2
0
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
Strain(ε)
True Stress - True Strain Graph
True stress( σ’ )
18
16
14
12
10
8
6
4
2
0
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
True strain( ε’ )
CALCULATIONS OF STRESS-STRAIN GRAPH
Engineering Stress ( σ ) = F ( kg ) / A0 ( mm^2 )
Engineering Strain ( ε ) = ΔL ( mm ) / L0
True Stress ( σ’ ) = σ( 1+ ε)
True Strain ( ε’ ) = ln( 1+ ε )
A0= π/4 * d0^2 mm^2= 113.04 mm^2
Stress y : Yield point of stress , Strain y : Yield point of strain
Modulus of Elasticity = Stress y / Strain y= 1,101069/0,00061= 1806,215436
σsut = Ultimate value of stress , εsut = ultimate value of strain
Toughness ( T0 ) = σulti * εulti = 14.97 * 0.13 = 1.94 (kg*mm/mm^3)
Energy İn Elastic Region= Δ σ / Δ ε = Stress 2 – Stress 1 / Strain 2 – Strain =
19,964628724 - 8,822078082 / 0,005588 - 0,0048768 = 1,142550642/ 0,0007112
= 1.606,511026434196
DUCTİLİTY İN ELONGATİON = |DELTAL/L0|*100 = 4,61518/ 50 *100 =
9,23036%
DUCTİLİTY İN REDUCTİON OF CROSS SECTİONAL AREA = |DF^2D0^2/D0^2|*100= (11^2- 12^2) / 12^2*100= 15,97222%
TRUE STRESS = STRESS(1+STRAİN) = 1,10106893(1+0,000609)=
1,10173948097837
TRUE STRAİN = LN(1+STRAİN)= LN(1+0,000609)= 6.088146348*10^-04
DISCUSSION
According to our data. We can clearly understand that our material
must be ductile. While doing this test we monitored the material get
necking. So this material’s diameter decreased. Therefore we can say
this material must be ductile.
REFERENCES
Lecture Notes of Dr A. Tolga Bozdana.
Lecture Notes of Prof. Dr Nihat Yıldırım..
Pictures has taken from Google Picture.
DATA BASE has taken from M. Furkan Kalkan.