Tensile Test Lab Report: Comparing Aluminium and Mild Steel Properties

This lab report details a tensile test experiment comparing the mechanical properties of aluminum and mild steel. The experiment utilized a Universal Tensile Machine to determine the yielding stress, strain, and ultimate strength of each material. The report includes a description of the experimental setup, materials used, and the testing procedure. Data collected, including extension, load, strain, and stress values, were recorded and analyzed. The results are presented in tables and graphs, illustrating the stress-strain behavior of both materials. The analysis focuses on comparing the yielding points, Young's Modulus, and plastic regions of the two metals, revealing that mild steel exhibits higher yielding stress and overall strength compared to aluminum. The report concludes by discussing the implications of these findings in engineering design and material selection, highlighting the suitability of each metal for different applications based on their tensile properties. Furthermore, the report acknowledges potential sources of error and offers suggestions for improving experimental accuracy.

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Tensile Test Lab Report
Student’s Name:
Tutor’s Name:
Abstract— designing in engineering is fundamentally on the basis of the properties of the material used
in the designing process and finally the manufacture of components in engineering. One of the paramount
properties of design materials is the strength. This report is a comparison in detail of the properties of two
metals. Aluminium and Mild Steel were tested on the Universal Tensile Machine to determine the strength
of each material. An analysis was done from the results obtained. The analysis is then used to predict the
features of the different metals when subjected to different loads as in the experiment. The conclusion from
comparing the two metals is that mild steel has a higher yielding stress and therefore a more strength than
Aluminium.
Keywords—Yiedling stress, Universal Tensile Machine, loads, Strength
I. INTRODUCTION
Application of engineering design expands through numerous fields in the real world. Designs from paper
and theory are put into real world to solve real world problems. Before any application of engineering
design in the various fields for example in the aircraft industry, railways building and transportation,
manufacture of plastics and pressure vessels, it is crucial to understand the characteristics of the material to
be used to manufacture some of these infrastructure and or equipment1 [1]. One of the important ways to
ascertain these properties is through carrying out a tensile test’s tensile test is carried out to determine the
yielding stress and time of a material in engineering. The test is done on a universal Tensile Machine.
The specimen which is an Aluminium and Mild Steel in these case is prepared for the test by marking and
cutting out a part on the specimen. It is at this point that the metal will be stretched and the results from how
1 J. R. Y. P. H. A. a. N. K. N. Pothnis, ". "High strain rate tensile behavior of aluminum alloy 7075 T651 and IS 2062 mild
steel."," Journal of Engineering Materials and Technology 133, no. 2 (2011): 021026., 2011

2
much load it can take in versus the time it takes to do so before it yields by snapping is recorded2 [2]. The
Tensile test can also be used to determine other properties of engineering materials for example the
3percentage elongation, and the ultimate strength. For further analysis of the properties of the material the
original gauge length and diameter are further used in calculations as will be indicated by the report.
II. METHODS
Apparatus
1. Universal testing machine
2. 3 Aluminium sample pieces
3. 3 Mild Steel samples pieces
4. Data recording program
5. Vernier callipers
Test procedure
1. The sizes of the specimens including their thickness and width were determined using the Vernier
callipers. The gauge length of the specimen was determined.
2. The workpieces were cut into a “dog-bone” shape after the gauge length of each specimen was
determined [3].
3. The work piece loaded into the universal testing machine after several adjustments had been made to
the machine including zeroing, and adjusting of the machine jaws, attaching of extensometers on the
machine’s reduced sections and using the scroll wheel where slippage was a problem.
4. Adjusted the extensometers to zero after removal of the specimen from the machine. Embarked on
measuring the strain of the specimen.
2 Q. K. D. O. V. S. R. a. F. J. Zhang, "Deep eutectic solvents: syntheses, properties and applications., " Chemical Society Reviews
41, no. 21 (2012): 7108-7146., 2012.
3J. R. Y. P. H. A. a. N. K. N. Pothnis, ". "High strain rate tensile behavior of aluminum alloy 7075 T651 and IS 2062 mild steel.","
Journal of Engineering Materials and Technology 133, no. 2 (2011): 021026., 2011.

3
5. To stop the test, separate the tensile grips at an incessant speed. Dictated by the shape of the
specimen. The results are plotted on a spreadsheet by the machine for analysis.
6. Concluded the test after the work piece breaks [4].4
III. RESULTS
TABLE I. RESULTS FROM THE EXPERIMENT
Mild Steel
Alumin
ums
Tim
e s
Extensio
n mm
Load
N
Strain
mm/mm
Stress
Mpa
Extensio
n mm
Load
N
Strain
mm/mm
Stress
Mpa
0 0 0.9 0 0.05 0 0.611 0 0.024
10 0.83
4694
.34 0.01 238.89 0.832
2687.
75 0.01
106.63
4
20 1.67
4831
.41 0.021 245.87 1.665
2884.
17 0.021
114.42
7
30 2.5
4781
.08 0.31 243.3 2.498
2981.
6 0.031
118.29
2
40 3.33
4918
.83 0.042 250.31 3.332
3048.
76 0.042
120.95
7
50 4.17
4926
.58 0.052 250.71 4.165
3071.
7 0.052
121.86
7
60 5
5257
.07 0.062 267.53 4.998
3112.
23 0.062
123.47
5
70 5.83
5437
.01 0.073 276.68 5.832
2877.
54 0.073
114.16
4
80 6.66
5575
.88 0.083 283.75 6.665
-
645.5
21 0.083 -25.61
81 6.75
5584
.21 0.083 283.75 6.665
-
645.5
21 0.084 -25.61
81.
1 6.76
5584
.04 0.084 284.17 6.757
-
791.9
85 0.084 -31.41
100 8.33
5775
.18 0.104 293.89
110 9.16
5847
.52 0.115 297.57
120 10
5911
.04 0.125 300.81
4 . R. P. a. M. A. Q. Ahamad, "Adsorption and inhibitive properties of some new Mannich bases of Isatin derivatives on corrosion
of mild steel in acidic media., " Corrosion Science 52, no. 4: 1472-1481., (2010)

4
130 10.83
5965
.41 0.135 303.57
140 11.67
6010
.53 0.146 305.87
150 12.5
6042
.57 0.156 307.5
160 13.33
6072
.26 0.167 309.01
170 14.16
6092
.93 0.177 310.06
180 15
6113
.24 0.187 311.1
190 15.83
6129
.65 0.198 311.93
200 16.67
6140
.36 0.208 312.48
0 0.05 0.1 0.15 0.2 0.25 0.3 0.35
0
50
100
150
200
250
300
350
Stress Vs Strain for Mild Steel
Stress Mpa
STRAIN mm/mm
STRESS Mpa
Graph I, Mild Steel

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0 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09
-40
-20
0
20
40
60
80
100
120
140
STRESS VS STRAIN-Al
Series2
STRESS VS STRAIN-AlSTRAIN mm/mm
STRESS Mpa
Graph II Aluminium
A. Equations
Stress=F / A
Strain= Force
Unit length

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IV. DISCUSSION
A. Micro-crysttaline Nature of the Specimen
The analysis of the dat from the test of the two metal samples indicates a difference. There is a difference in
the rate and length of extesnsions in Aluminium as compared to that in Mild Steel. The calculations for the
strain, stress and length of the two samples when compared also show diffrences in the properties of the two
metals. Aluminium extends more and recorded more extension than Mild steel 5[5]. All these is an
indication of the difference in the microcrystalline nature of the two metals. The material science of the two
materials diifferes greatly in that the atoms of Mild stell are closely packed as compared to those of
Aluminium. It gives mild steel a upper hand because it is hard to breal this closely packed atoms connected
with strong bonds [6].6
B. Yield Points
Mild Steel reached its yielding point at 240 Mpa whereas Aluminium reached its yielded at 105 Mpa.
Comparing the gradients of both metals from the Stress-Strain graphs to obtain the Young’s Modulus, we
also find that Mild Steel has a higher Young’s Modulus than Aluminium [7].7 It therefore means that before
it deflects, Mild Steel takes up a lot of load as compared to Aluminium [4]. Loading of the specimens after
they have yielded determines there plastic region- appoint where irreversible damage is caused on the
metals specimen. For Mild Steel, this point was at approximately335 Mpa while for Aluminium was at 80
MPa [8].8 Mild steel has high values of strain and stress. After necking has occurred it can be clearly seen
5
6
7
8
5H. A. I. M. I. E. R. a. Z. A. A. Seli, "Mechanical evaluation and thermal modelling of friction welding of mild steel and
aluminium, ." Journal of Materials Processing Technology 210, no. 9 : 1209-1216., (2010).
6T. T. M. a. T. H. Tanaka, "Comprehensive analysis of joint strength for dissimilar friction stir welds of mild steel to aluminum
alloys., " Scripta Materialia 61, no. 7 (2009): 756-759., (2009).
7K. Y. M. K. M. M. S. a. M. K. Suzuki, "Tensile and microbend tests of pure aluminum foils with different thicknesses.",
Materials Science and Engineering: A 513 (2009):, 2009, pp. 77-82..
8D. S. Dugdale, ""Yielding of steel sheets containing slits."Journal of the MechanicsandPysics of Solids".(2011): pp. 100-114

7
from the graphs that the graph drops downwards. Strain hardening could be the major cause of the high
strain in mild Steel.
V. CONCLUSION
In conclusion, the tensile test provides a very insightful study of the material science of different
engineering materials. The results and conclusion enable the engineers to apply the materials in the suitable
industry for quality and safety of the people who are going to use the components made from the materials.
Mild steel for instance has a very high yielding point. The compact nature of the microstructure of Mild
Steel enables it to withstand more load before it necks and or yields. Also the axial loads are well withstood
by Mild Steel giving it a very high strain power. Its application n therefore lies in the high tensile zones for
example manufacture of chisels. Aluminium is applied in industries that require low density material for
example the aviation industry due to its nature of ductility and low yield points. In general, experimental
results and analysis as compared with the theoretical values proves that the experiment was well within the
required margin of error. There might have been slight errors for example during the measuring with the
callipers-parallax error. However this should be avoided in future by ensuring that all readings are taken
perpendicularly from the instrument.

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ACKNOWLEDGMENT
VI. WORKS CITED
[1] J. R. Y. P. H. A. a. N. K. N. Pothnis, ". "High strain rate tensile behavior of aluminum alloy 7075 T651 and IS 2062 mild
steel."," Journal of Engineering Materials and Technology 133, no. 2 (2011): 021026., 2011.
[2] Q. K. D. O. V. S. R. a. F. J. Zhang, "Deep eutectic solvents: syntheses, properties and applications., " Chemical Society
Reviews 41, no. 21 (2012): 7108-7146., 2012.
[3] H. K. G. J. R. G. P. a. K. P. R. Rafi, "Microstructural evolution during friction surfacing of tool steel H13, ." Materials &
Design 32, no. 1 (2011):, 2011, pp. 82-87..
[4] I. R. P. a. M. A. Q. Ahamad, "Adsorption and inhibitive properties of some new Mannich bases of Isatin derivatives on
corrosion of mild steel in acidic media., " Corrosion Science 52, no. 4: 1472-1481., (2010).
[5] H. A. I. M. I. E. R. a. Z. A. A. Seli, "Mechanical evaluation and thermal modelling of friction welding of mild steel and
aluminium, ." Journal of Materials Processing Technology 210, no. 9 : 1209-1216., (2010).
[6] T. T. M. a. T. H. Tanaka, "Comprehensive analysis of joint strength for dissimilar friction stir welds of mild steel to
aluminum alloys., " Scripta Materialia 61, no. 7 (2009): 756-759., (2009).
[7] K. Y. M. K. M. M. S. a. M. K. Suzuki, "Tensile and microbend tests of pure aluminum foils with different thicknesses.",
Materials Science and Engineering: A 513 (2009):, 2009, pp. 77-82..
[8] D. S. Dugdale, ""Yielding of steel sheets containing slits."Journal of the MechanicsandPysics of Solids".(2011): pp. 100-114
[9]
[9]SUPPLEMENTARY MATERIALS
GRAPH III. THEORETICAL GRAPH OF STEEL AND ALUMINIUM