Tensile Testing – Data Sheet
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Please fill in your name, group
members, data and instructor’s name
Mark gage length indents using the
hammer
Measure the original diameter and gage
length
Material is 2024-T351 Al alloy
Today’s Specimen
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2024-T351 Aluminum Alloy
Contains ~94% (Al), ~4.5%(Cu), 1.5%
(Mg)
Used in aircraft fittings, gears and
shafts, missile parts, veterinary and
orthopedic equipment
You can use info for 2024-T3 for
comparison
Data Sheet
Data Sheet (continued)
After Testing
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Record load & strain when extensometer was
taken off
Record maximum load and approximate load
at yield
Measure final diameter and gage length
Record data filename
Either sketch or photograph the fractured
surfaces
Compute the parameters on the reverse side
of data sheet
Data Sheet
Lab Report #2: due next week
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Cover Page + Abstract (10 points)
Data Sheet (5 points)
Spreadsheet of Raw/Processed Data
Relevant Plots (20 points)
Materials Properties Table (5 points)
Comments and Conclusions (15 points)
Tensile Properties
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Quantitative determination of
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Elastic Modulus, E
Proportional Limit, PL
0.2% Offset Yield Strength, Y
Tensile Strength, TS
% Elongation to Failure, %f
Modulus of Toughness, Atotal
Qualitative study of Failure
Tensile Testing –
Processing Data
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Importing data into Excel
Correcting data for physical slack
Setting up the spreadsheet
Computing stresses and strains
Entire stress-strain curve
Elastic portion and modulus
Proportional limit and yield strength
Modulus of Toughness
Fitting spreadsheet into one page
Lab Report Template
Importing Data into Excel
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In Excel: File  Open (choose file)
Dialog: Do you want to open the file now?  click on
“Yes” button
Steps 1-3: click Next Next Finish
Correcting data for initial slack
Identify a row when both strain and force
increase monotonically (in our case  row
550) : see next two slides
{it may help to plot the data up to ~2000lb}
 Subtract this initial strain and force value
from each subsequent row (in our case:
0=2.05E-02%, F0=1.05E+03 lb)
 See next two slides
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Identifying the New Origin
Strain = 2.05E-02
Force = 1.50E+03
Correcting Raw Data
=A550-$A$550
=B550-$B$550
0 decimal digits
3 decimal digits
Format Data and Plots
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Load in lbs - 1 decimal digit
Strain in % - 3 decimal digits
Stress in psi – 0 decimal digits
Strain in in/in – 2 decimal digits (sci notation)
Energy in psi - 2 decimal digits (sci notation)
Format one row; then COPY + PASTE
SPECIAL (format only) to other rows
Check axis scales in all the plots
Print the plots before hiding rows
Spreadsheet Setup
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In a New Worksheet
Set up cells as shown below
A0 = D02/4
Af = Df2/4
Compute Stresses & Strains
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=Load/A0
0 dec digits
Copy & Paste Special (Values & Formats only)
“corrected” data
Compute stress & strain for first row
= Ln(1 + )
2 dd sci
=%strain/100
2 dd sci
=  (1 + )
0 dec digits
Stresses & Strains
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Format strain cells (scientific, 2 decimals)
Format stress cells (number, 0 decimal)
Copy formulas for each subsequent row
{Note true stress & strain formulas are valid
only up to the maximum load}
Plot Stress-Strain Curves
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Select data in columns C, D, E & F
Plot smooth curves (no data markers)
Move the chart to a new worksheet
Delete gridlines
Adjust True Stress curve so that it is plotted
against data in column E (see next slide)
Adjust axis titles and values (see the plot)
Adjusting True Stress Curve
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Right Click on plot  Select Data…
Adjusting True Stress Curve
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Replace “C” by “E” in “Series X Values” box
Stress-Strain Curves
Elastic Modulus
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Select data in columns C & D up to a stress
value that shows linearity
Plot data markers
Move chart to a new worksheet
Delete gridlines
Fit a straight line thru’ the origin
Format the plot labels, axes and line-fit
results as appropriate (see next slide)
Elastic Modulus Plot
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Enter E = 29.60 Msi in cell I5
Select data points by
clicking on any and then
Right-click and choose
“Add Trendline”
Proportional Limit and
0.2% Offset Yield Strength
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In column H, enter formula: = E * Engg Strain
Adjust format, and copy it down until the stress value
slightly exceeds Engg Stress
In column G, beginning at row where Engg Strain
slightly exceeds 0.002 (-0.2%), enter formula: = E *
(Engg Strain – 0.002)
Adjust format, and copy it down until the stress value
slightly exceeds Engg stress
Proportional Limit and Yield Strength
Elastic Modulus, Em
Begin at Estrain = 0.002
= Em * (Estrain – 0.002)
Stop 78643 > 75792
= Em * EStrain
Stop 69702 > 64779
Plot Curve & Lines
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Plot data in columns C, D, G, H (smooth
curves, no data markers)
Format plot labels, axes etc. (see next
slide)
Proportional Limit and
0.2% Offset Yield Strength
Data Point @ failure
same
Strain Energies and
Modulus of Toughness
Modulus of Toughness
using Trapezoidal Rule
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{Note no entry in Row 13}
Enter formula for width: =C14 – C13
Enter formula for average height:
= (D14 + D13)/2
Enter formula for area: = I14 * J14
Adjust formats, and copy all formulas down
to the last row (point@failure)
Modulus of Toughness is the sum of all area
values (see next slide)
Modulus of Toughness
using Trapezoidal Rule
= C14 – C13
2 dd sci
= (D14 + D13)/2
0 dec digits
=I14 * J14
2 dd sci
Materials Property Tables
Triangular
Area
Comparison with Lab #1
Adjust Spreadsheet of data to
fit one page by hiding rows
Format Data and Plots
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Load in lbs - 1 decimal digit
Strain in % - 3 decimal digits
Stress in psi – 0 decimal digits
Strain in in/in – 2 decimal digits (sci notation)
Energy in psi - 2 decimal digits (sci notation)
Format one row; then COPY + PASTE
SPECIAL (format only) to other rows
Check axis scales in all the plots
Print the plots before hiding rows
Lab Report Grading Rubric ..1
Lab Report Grading Rubric ..2
Lab Report Grading Rubric ..3
Lab Report due next week
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{note that when you hide rows, it may distort
your plots}
Answer multiple-choice questions and student
survey ONLINE before the due-date
Review your lab report before submitting in
the box under your mailfolders
Select box “MECE-204: Strength Lab”