Lab Report Compression Test PDF

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Compression Test Lab Report. Prepared by UMP students...

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FACULTY OF MECHANICAL ENGINEERING “In the name of Allah, The Most Beneficent, The Most Merciful”

Lab #02

Compression Test (Short Report) Prepared By Dayangku Noorfazidah binti Awang Sh’ri Edited By Mahendran A/L Samykano Fakulti Kejuruteraan Mekanikal, Universiti Malaysia Pahang Lab Location Strength of Materials Lab

Results

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Discussion

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Conclusion

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Writing Skill

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Total

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5

Lab Objectives By the end of this lab, students should be able to:  Conduct compression test for different material and obtain stress-strain curve for each material  Use stress-strain curve to determine the proportional limit and compressive strength of the materials Group No.

100

Date:

02nd January 2022

Group Members Andi Mohd Kamaruddin bin Karim Tuan Muhammad Abdullah bin Tuan Fuzai Ahmad Zikrillah bin Mat Sidek Muhammad Amir Firdaus bin Azman@Azamani Joshua Abel Liew Tze Tshung

Student ID MA19337 MA19338 MA19339 MA19340 MA20173

Section F01 F01 F01 F01 F01

Page 2 of 9

1.0 Compression Test A compression test determines behavior of materials under crushing loads. It is conducted in a manner similar to tensile test, except that the force is compressive and the specimen contracts along the direction of the stress.1 The specimen is compressed and deformation at various loads is recorded. Compressive stress and strain are calculated and plotted as a stress-strain diagram which is used to determine elastic limit, proportional limit, yield point, yield strength and, for some materials, compressive strength. When a simple compressive load is applied to a specimen, the following types of deformation may take place: elastic or plastic shortening in ductile materials, crushing and fracture in brittle materials, a sudden bending deformation called buckling in long, slender bars, or combinations of these. Ductile materials, such as mild steel, have no meaningful compressive strength. Lateral expansion and thus an increasing cross-sectional area accompany axial shortening. The specimen will not break: excessive deformation rather than loss of strength often characterize failure. Brittle material commonly fracture along a diagonal plane which is not the plane of maximum compressive stress, but rather one of high shear stress which accompanies the uniaxial compression. Strain is a measure of the intensity of deformation (deformation per unit length). Normal strain, ε, measures the contraction (or elongation) of a body during deformation.

Figure 1 Initial measurement of testing sample Several calculations will be required to determine the properties of each sample.

Elastic Modulus:

𝐸

Proportional Limit:

 

𝜎 

Compressive Strength:



𝜎 

   

Figure 2 Stress-strain graph for compression test

Modulus of Resilience:

BMM2521 Engineering Mechanics Lab 11_1011/2_2_(SR)_Compression_Test (1).doc

𝑈 

  𝜎 .   

Page 3 of 9

2.0 Experiment Setup Test Preparation 

The length and cross-sectional dimensions of each specimen must be measured prior to testing.

Equipment & Materials  

Equipment: INSTRON 50kN Material: Mild steel, Aluminum, Brass

Experiment Procedure 1.

Identify each specimen and record the initial dimensions of the specimen. Material Mild Steel Aluminum Brass

Initial Height (mm) 10.2 10.3 10.5

Inner Radius (mm) 7.9 7.8 8.1

Outer Radius (mm) 10.3 9.4 10.5

Final Height (mm) 9.0 8.2 8.5

2 2. 3. 4.

Set up the testing machine for compression, and place the specimen between the plates. Compress the specimen in increments until reaching a desired final height. The specimen may now have a barrel shape. Discontinue the test and measure the final dimensions of the specimen

BMM2521 Engineering Mechanics Lab 11_1011/2_2_(SR)_Compression_Test (1).doc

Page 4 of 9

3.0 Results – Calculation and graph 1. 2.

For each material tested, plot the corresponding stress vs. strain. Identify the proportional limit and compressive strength as shown in Figure 2. Calculate the elastic modulus and modulus of resilience using the formula given.

STRESS‐ STRAINCURVEFORMILDSTEEL 30

Stess(N/mm2)

25 20 15 10 5 0 0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

Strain(mm/mm)

Sample : Mild Steel Properties Elastic Modulus Proportional Limit Compressive Strength Modulus of Resiliency

Value -

BMM2521 Engineering Mechanics Lab 11_1011/2_2_(SR)_Compression_Test (1).doc

5

Page 5 of 9

STRESS‐ STRAINCURVEFORALUMINUM 30

Stess(N/mm2)

25 20 15 10 5 0 0

0.5

1

1.5

2

2.5

Strain(mm/mm)

Sample : Aluminum Properties Elastic Modulus Proportional Limit Compressive Strength Modulus of Resiliency

Value -

BMM2521 Engineering Mechanics Lab 11_1011/2_2_(SR)_Compression_Test (1).doc

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Page 6 of 9

STRESS‐ STRAINCURVEFORBRASS 30

Stess(N/mm2)

25 20 15 10 5 0 0 ‐5

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

Strain(mm/mm)

Sample : Brass Properties Elastic Modulus Proportional Limit Compressive Strength Modulus of Resiliency

Value -

BMM2521 Engineering Mechanics Lab 11_1011/2_2_(SR)_Compression_Test (1).doc

5

Page 7 of 9

4.0 Dicussion 1.

Explain the differences between compression test and tensile test? Tensile Test – The test specimen was pulled apart under the tension forces (positive direction or upward). Compression Test – The test specimen was squished until break under the compensive forces (negative direction or downward)

2 2.

Based on your result, please compare and contrast the difference between each material used in this lab. Based on the result achieve, the experiment failed to compare the and contrast the difference between each material used. The possible cause for this failure is because of the inccorrect data received. The data between load and extension may exchanged.

2 3.

Explain in your own word why the compression testing is important in manufacturing industry. Compressive test is important in the manufacturing industry because it will show the behaviour of the materials when being compressed or under high loads. Compression test also able to measure the plastic flow behaviour and ductile fracture limits of a material. The maximum compressive strength value is important during the material selection in any particular engineering.

2

BMM2521 Engineering Mechanics Lab 11_1011/2_2_(SR)_Compression_Test (1).doc

Page 8 of 9

5.0 Conclusion Each materials have a different properties. Some materials may have high tensile strength but have a lower properties at others. In any engineering project, it is important to perform multiple test prior to material selction. One of the major test that need to be performed is compression test. Compression test can be used to measure the elastic and compressive fracture propertires of brittle materials or lowductility materials.

2

BMM2521 Engineering Mechanics Lab 11_1011/2_2_(SR)_Compression_Test (1).doc

Page 9 of 9

6.0 References 1. Callister, W.D, “Materials Science and Engineering: An Introduction”, (2003) 6th Edition, John Wiley & Sons, Inc, New York.

BMM2521 Engineering Mechanics Lab 11_1011/2_2_(SR)_Compression_Test (1).doc...