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Tensile Testing – Data Sheet
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 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 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 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
Quantitative determination of 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 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 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
Identifying the New Origin
Strain = 2.05E-02Force = 1.50E+03
Correcting Raw Data
=A550-$A$550
=B550-$B$550
3 decimal digits
0 decimal digits
Format Data and Plots 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 In a New Worksheet Set up cells as shown below
A0 = D0
2/4
Af = Df2/4
Compute Stresses & Strains Copy & Paste Special (Values & Formats only)
“corrected” data Compute stress & strain for first row
=%strain/1002 dd sci
=Load/A0
0 dec digits
= (1 + )0 dec digits
= Ln(1 + )2 dd sci
Stresses & Strains 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 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
Right Click on plot Select Data…
Adjusting True Stress Curve Replace “C” by “E” in “Series X Values” box
Stress-Strain Curves
Elastic Modulus 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 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 and0.2% Offset Yield Strength 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
= Em * EStrain
Stop 69702 > 64779
Begin at Estrain = 0.002
= Em * (Estrain – 0.002)
Stop 78643 > 75792
Plot Curve & Lines Plot data in columns C, D, G, H
(smooth curves, no data markers) Format plot labels, axes etc. (see
next slide)
Proportional Limit and0.2% Offset Yield Strength
Data Point @ failure
same
Strain Energies and Modulus of Toughness
Modulus of Toughnessusing Trapezoidal Rule {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 Toughnessusing Trapezoidal Rule
= C14 – C132 dd sci
= (D14 + D13)/20 dec digits
=I14 * J142 dd sci
Materials Property Tables
TriangularArea
Comparison with Lab #1
Adjust Spreadsheet of data to fit one page by hiding rows
Format Data and Plots 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 {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”
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