Concept explainers
(a)
The predicted crack length at fracture.
(a)
Answer to Problem 11.12P
The predicted crack length at fracture is
Explanation of Solution
Given:
The critical stress intensity factor is
The minimum detectable crack length is
Stress range is
Mean stress is
Concept used:
Write the expression for stress intensity range.
Here,
For internal cracks the value of geometrical factor is
Calculation:
Substitute
Calculate the critical length of failure.
Conclusion:
Thus, the predicted crack length at fracture is
(b)
Lifetime of part based upon fatigue crack propagation.
(b)
Answer to Problem 11.12P
Lifetime of part based upon fatigue crack propagation is
Explanation of Solution
Given:
Rate of crack growth is
Concept used:
Write the expression for the number of crack propagation cycle to failure.
Here,
Write the expression for crack growth rate.
Take log on both sides.
The above expression represents a straight line with slope
Calculation:
Substitute
Conclusion:
Thus, the Lifetime of part based upon fatigue crack propagation is
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Chapter 11 Solutions
Materials Science And Engineering Properties
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- Materials Science And Engineering PropertiesCivil EngineeringISBN:9781111988609Author:Charles GilmorePublisher:Cengage Learning