Solid Mechanic
Chapter Objectives
Understand how to measure the stress and strain through experiments Correlate the behavior of some engineering materials to the stress-strain diagram.
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In-class Activities
1. 2. 3. 4. 5. 6. 7. Reading Quiz Applications Stress-Strain diagram Strength parameters Poisson’s ratio Shear Stress-strain diagram Concept Quiz
Copyright © 2011 Pearson Education South Asia Pte Ltd
TENSION AND COMPRESSION TEST
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READING QUIZ
1) The modulus of elasticity E is a measure of the linear relationship between stress and strain. The common unit is:
a) kN/mm2
b)
c)
MPa
GPa
d)
All of them
Copyright © 2011 Pearson Education South Asia Pte Ltd
READING QUIZ (cont)
2) The Poisson’s ratio, v of common engineering materials lies in the range:
a) b) c) d) 0≤v≤1 0 ≤ v ≤ 0.5 -1 ≤ v ≤ 1 -0.5 ≤ v ≤ 0.5
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APPLICATIONS
Copyright © 2011 Pearson Education South Asia Pte Ltd
APPLICATIONS (cont)
Copyright © 2011 Pearson Education South Asia Pte Ltd
STRESS STRAIN DIAGRAM • Note the critical status for strength specification proportional limit elastic limit yield stress ultimate stress fracture stress
Copyright © 2011 Pearson Education South Asia Pte Ltd
STRENGTH PARAMETERS • Modulus of elasticity (Hooke’s Law)
E
• Modulus of Resistance
1 1 pl ur pl pl 2 2 E
2
•
Modulus of Toughness – It measures the entire area under the stress-strain diagram
Copyright © 2011 Pearson Education South Asia Pte Ltd
EXAMPLE 1
The stress–strain diagram for an aluminum alloy that is used for making aircraft parts is shown in Fig. 3–19. If a specimen of this material is stressed to 600 MPa, determine the permanent strain that remains in the specimen when the load is released. Also, find the modulus of resilience both before and
Understand how to measure the stress and strain through experiments Correlate the behavior of some engineering materials to the stress-strain diagram.
Copyright © 2011 Pearson Education South Asia Pte Ltd
In-class Activities
1. 2. 3. 4. 5. 6. 7. Reading Quiz Applications Stress-Strain diagram Strength parameters Poisson’s ratio Shear Stress-strain diagram Concept Quiz
Copyright © 2011 Pearson Education South Asia Pte Ltd
TENSION AND COMPRESSION TEST
Copyright © 2011 Pearson Education South Asia Pte Ltd
READING QUIZ
1) The modulus of elasticity E is a measure of the linear relationship between stress and strain. The common unit is:
a) kN/mm2
b)
c)
MPa
GPa
d)
All of them
Copyright © 2011 Pearson Education South Asia Pte Ltd
READING QUIZ (cont)
2) The Poisson’s ratio, v of common engineering materials lies in the range:
a) b) c) d) 0≤v≤1 0 ≤ v ≤ 0.5 -1 ≤ v ≤ 1 -0.5 ≤ v ≤ 0.5
Copyright © 2011 Pearson Education South Asia Pte Ltd
APPLICATIONS
Copyright © 2011 Pearson Education South Asia Pte Ltd
APPLICATIONS (cont)
Copyright © 2011 Pearson Education South Asia Pte Ltd
STRESS STRAIN DIAGRAM • Note the critical status for strength specification proportional limit elastic limit yield stress ultimate stress fracture stress
Copyright © 2011 Pearson Education South Asia Pte Ltd
STRENGTH PARAMETERS • Modulus of elasticity (Hooke’s Law)
E
• Modulus of Resistance
1 1 pl ur pl pl 2 2 E
2
•
Modulus of Toughness – It measures the entire area under the stress-strain diagram
Copyright © 2011 Pearson Education South Asia Pte Ltd
EXAMPLE 1
The stress–strain diagram for an aluminum alloy that is used for making aircraft parts is shown in Fig. 3–19. If a specimen of this material is stressed to 600 MPa, determine the permanent strain that remains in the specimen when the load is released. Also, find the modulus of resilience both before and