Drexel University
College of Engineering
Department of Engineering, Leadership and
Society
Engineering Technology
MET 101 Engineering Materials
Laboratory Experiment No. 1
Tensile Test
Lab Report No. 1
By Thomas Gillis
Date: 4/26/24
Purpose:
The objective of this laboratory session is to acquaint oneself with the process of conducting a
tensile test using a universal testing machine. This test involves assessing various mechanical
properties including stress, strain, ductility, modulus of elasticity, and toughness of the materials
under examination.
Description/Data:
The assessment of tensile properties in materials requires employing a standardized tensile
specimen of the material being tested. This specimen is subjected to elongation between the grips
of a machine, resulting in a load (P) versus elongation (∆l) curve. The load (P) at various test
points is converted to unit stress (σ) by dividing it by the gage area. Additionally, strain values
(ε) are calculated as the ratio of elongation (∆l) at each point to the original length (l0) of the
specimen, also referred to as the gage length.
For this experiment we were primarily observers as we watched each and every material get
stretched out, with the addition of one compressed material. From what I observed the steel rod
was the loudest of the materials and when it snapped, and it was the only material where the split
occurs towards more of the bottom half rather than the top. The Aluminum material was
interesting in its own right as it was the only material where the break was diagonal rather than
horizontal like all the others. The Acrylic is probably the most unremarkable one out of the
bunch, however its break is probably the cleanest and most horizontal. The PVC was very unique
because no other material was as stretchy as PVC which got me thinking if that was the reason it
was mostly for Pipes and wires as it would be very hard to break by pulling and if something did
try, it would probably only stretch the material out. Finally, we compressed a tic-tac container
and although there is no other material to really compare it to it was interesting to see how
necking almost mirrors the containers crumbling as one part starts and then it is all over from
there. The linear range appears to be from 0 to 151.2 lbf with 151.2lbf appearing to be as much
as force as the tic tac case can hold.
Summary
Overall To put it simply, we recorded the Gage length, Diameter, Thickness and Width before
and after the use of the machine with addition of compressing the tic-tac container and we
recorded how those measurements have changed after utilizing the machine. The machine
stretched pulled and overall elongated each and every one of the materials and after gathering the
data needed, we used it solve equations that helped us get a better understanding of the
mathematical aspects that come with stretching and compressing different materials.
.
Equations For Steel Rod Example
Gage Area (0) -------- pi/r^2 –---------- 3.14/(.125/2)^2 = .01227
Ductility ------------(Lf – Li) / Li ------------(5.3-5) / 5 = .06
Area Reduction --------(Ai – Af) / Ai ---------(.01227 - .0109) / .01227 = .11
E -------------- delta Stress / delta Strain ------------ 284426/3480 = 81.731
Toughness ----------- Parallelogram under curve = b*h ----------.075 *250000 = 18750
Shear Modulus ---------- E * 3/8 ------------ 81.731 * 3/8 = 30.649
The steel rod when compared to the properties of steel table appears to be Material no. 5160
OQT 700 based off its elongation and power.
Data Table
Properties and
Dimensions
Steel Rod (P Delta l)
Aluminum 6061T6 (P - Delta l)
Acrylic (PDelta l)
PVC (P - Delta
l)
Gage Length (L0) 5in
2in
2in
2in
Gage Diameter
(D0)
.125in
X
X
X
Gage Thickness
(T0)
X
.125in
.120in
.125in
Gage Width (W0) X
.53in
.520in
.534in
Gage Area (A0)
.01227in
.06625in
.0624in
.6675in
Py (lb)
3200
2700
430
300
Pu (lb)
3480
3070
439
488
Pf (lb)
3250
2320
270
243
oy (psi)
260759.5
220015.8
35039.5
24446.2
ou (psi)
285245.9
250166.1
35772.9
39765.8
of (psi)
264833.8
189050.6
22001.6
19801.4
Final Diameter
(Df)
.118in
X
X
X
Final Thickness
(Tf)
X
.088in
.115in
.070in
Final Width (Wf)
X
.467in
.519in
.351in
Final Length (Lf)
5.3in
2.375in
2.043in
3.284in
Gage Area (Af)
.0109in
1.109in
.060in
1.155in
Ductility ef (%)
6%
19%
2%
64%
Area Reduction
(%)
11%
-94%
4%
-42%
E (psi x 10^6)
81.73
15.09
92503.42
601.01
Shear Modulus G
~ 3/8 E (psi x
10^6)
Toughness (lb*
in/in^3)
30.65
5.66
34688.78
225.38
18750
10400
225
412
Graphs
Steel: Force vs Elongation
4000
3500
Force (lbf)
3000
2500
2000
1500
1000
500
0
-500
0
0,05
0,1
0,15
0,2
0,25
0,3
0,35
0,4
0,06
0,07
0,08
Elongation (in)
Steel: Stress
vs. Strain
Stress (lb/in^2)
300000
250000
200000
150000
100000
50000
0
-50000
0
0,01
0,02
0,03
0,04
0,05
Strain (in/in)
Steel: Young's Modulusy = 2E+06x - 786.7
Stress (lb/in^2)
4000
3500
3000
2500
2000
1500
1000
500
0
0
0,0005
0,001
0,0015
0,002
0,0025
0,003
Strain (in/in)
Aluminum: Force vs Elongation
3500
3000
Force (lbf)
2500
2000
1500
1000
500
0
-500
0
0,1
0,2
0,3
0,4
0,5
0,6
0,25
0,3
Elongation (in)
Aluminum: Stress vs. Strain
Stress (lb/in^2)
50000
40000
30000
20000
10000
0
0
-10000
0,05
0,1
0,15
Strain (in/in)
0,2
Aluminum: Young Modulus
Stress (lb/in^2)
600
y = 170329x + 52.397
500
400
300
200
100
0
0
0,0005
0,001
0,0015
0,002
0,0025
0,003
Strain (in/in)
Force (lbf)
Acrylic: Force vs. Elongation
500
450
400
350
300
250
200
150
100
50
0
-50 0
0,02
0,04
0,06
0,08
0,1
0,12
0,14
0,16
0,18
0,07
0,08
0,09
Elongation (in)
Acrylic: Stress vs. Strain
8000
Stress
(lb/in^2)
7000
6000
5000
4000
3000
2000
1000
0
-1000
0
0,01
0,02
0,03
0,04
0,05
Strain (in/in)
0,06
Acrylic: Young's Modulus
y = 63774x + 45.035
180
Stress (lb/in^2)
160
140
120
100
80
60
40
20
0
0
0,0002
0,0004
0,0006
0,0008
0,001
0,0012
0,0014
0,0016
0,0018
0,002
1,4
1,6
1,8
Strain (in/in)
PVC: Force vs. Elongation
600
Force (lbf)
500
400
300
200
100
0
0
-100
0,2
0,4
0,6
0,8
1
Elongation (in)
1,2
PVC:
Stress vs. Strain
800
Stress lb/in^2)
700
600
500
400
300
200
100
0
-100
0
0,1
0,2
0,3
0,4
0,5
0,6
0,7
0,8
0,9
Srain (in/in)
Stress (lb/in^2)
PVC: Young's Modulus
y = 10103x + 2.238
20
18
16
14
12
10
8
6
4
2
0
0
0,0002
0,0004
0,0006
0,0008
0,001
Strain (in/in)
0,0012
0,0014
0,0016