ME 324 – LAB #1
MECHANICAL TESTING
Part 1: Uniaxial Tension Test
Reading Assignment: 2.1, 2.2
Apparatus:
SATEC Universal testing machine
Caliper
Micrometer
Gage length punch
Materials and Specimens:
Aluminum 2011
Gray Cast Iron
AISI 1020 Steel
Procedure:
1. Using a caliper, measure the width and thickness at several locations along
the shaft of each specimen to determine the average cross-sectional dimensions.
Record the average measured width and thickness of each specimen on the data sheet.
2. Place the specimen in the grips. Make sure that each end is firmly attached to the
grips.
3. Punch the gage length on the shaft of the specimens using the gage length punch.
4. Measure the length of the specimen between the punch marks. This is the gage
length and will be used to calculate strain.
5. Adjust the caliper for a length slightly larger than the gage length and record that
length.
6. Adjust the micrometer for a slightly smaller diameter than the original diameter of the
shaft and record that diameter.
7. Begin applying the tensile load to the specimen and observe the live reading of
applied load on the digital display. The read-out displays the applied tensile load in
Newtons.
8. Continue applying tensile load slowly, observing the shape of the sample closely.
Check frequently until sample reaches the adjusted length on caliper and record the
corresponding load. Repeat step 5.
9. Repeat step 8 until specimen diameter starts to change. Check for change in
diameter frequently using the micrometer.
10. Check the diameter and the length of the specimen until they reach the adjusted
values on the caliper and micrometer, record the corresponding load values. Repeat
steps 5 and 6.
11. Load the specimen until failure and repeat step 10 until failure. Record the maximum
load and the load at failure.
12. Remove the broken specimen from the machine. Observe the location and character
of the fracture.
13. Measure the width and thickness of each specimen in the region of failure and
record final measurements.
Part 2: Hardness test
Reading Assignment: 2.6
Apparatus:
Brinell hardness Testing Equipment
Rockwell Hardness testing Equipment
Scope
Materials and Specimens:
Aluminum 6061
Brass (Cu-Zn)
AISI 302 Stainless Steel
AISI 4140 Steel
Procedure:
Brinell hardness Test
1. Place the specimen under the indenter on the circular platform.
2. Bring specimen in slight contact with the indenter by moving
the specimen upwards slowly; stop at contact.
3. Push the lever arm on the right side of the testing equipment
and release as the load takes over.
4. Pull the lever arm back after the test is completed and lower
the specimen.
5. Move specimen around over the platform to carry out the next
test at a different location on the specimen. Repeat steps 2,3,
and 4.
6. Repeat step 5 until you get 5 indentations.
7. Remove the specimen and measure the indentation diameters
using the scope. Record your readings.
Rockwell Hardness Test
1. Place the specimen on the circular platform.
2. Bring specimen in slight contact with the indenter by moving
the specimen upwards slowly; observe the digital minor load
display and stop at test range. The equipment will take over
and carry out the test.
3. Record the hardness value from the digital display.
4. Move the platform down and move specimen around over the
platform to carry out the next test at a different location on the
specimen. Repeat steps 2, and 3.
5. Repeat step 4 until you get 5 hardness readings.
LAB #1 DATA SHEET
MATERIAL
Initial Diamater Do
Gage Length Lo
Yield load, PY
Yield Length, LY
Maximum Load, PU
#1
#2
#3
#4
TENSION TEST R E S U L T S
#1
#2
#3
#4
Length at Maximum Load, LU
Fracture Load, PF
Fracture Length, LF
Initial Area, Ao
Yield Strength, σY
Ultimate Tensile
Strength, σUTS
Young's Modulus, E
Final Area, AF
% Area Reduction
% Elongation
Strain Hardening
Coefficient, K
Strain Hardening
Exponent, n
H A R D N E S S
Brinell Hardness Test
Indentation
Diameter, d
T E S T
#1
#2
#3
#4
d1
d2
d3
d4
d5
Indenter Diameter, D
Average indentation
diameter, dAVE
BHN
Rockwell
Hardness Test
Hardness Readings
1
2
3
4
Average
Rockwell Hardness
Length
Diameter
Report:
Complete reading assignment before you start with the report.
Uniaxial tension test: 70 %
Complete the data sheet and present as a table.
Plot engineering stress-strain curve for AISI 1020 steel.
Calculate E, YS, and UTS using the plot.
Plot true stress-strain curve for AISI 1020 steel.
Calculate E, YS, UTS, K, and n using the plot.
Show sample calculations.
Summarize
Hardness tests: 30 %
Complete data sheets and present as tables.
Show sample calculations.
Summarize
Follow the general rules for report writing given in the web site. The data sheet given
with this outline is a sample. Rearrange your results and present them in the form of
tables and graphs according to the guidelines.
By Emrah Simsek