Concept explainers
(a)
The total stage II creep strain theory for the alloy.
(a)
Answer to Problem 9.5P
The total stage II creep strain theory for the alloy at
Explanation of Solution
Given:
The tensile stress of super alloy is
The creep-rate equation is
Formula Used:
Write the expression for the total stage II creep strain as:
Here,
Calculation:
Substitute
Conclusion:
Thus, the total stage II creep strain theory for the alloy at
(b)
The stage II creep rate of the alloy at
(b)
Answer to Problem 9.5P
The stage II creep rate of the alloy at
Explanation of Solution
Given:
The tensile stress of super alloy is
The creep-rate equation is
Formula Used:
Write the expression for the tensile stage II creep strain.
Here,
Write the expression for the ratio of strain rates of
Here,
Calculation:
Substitute
Conclusion:
Thus, the stage II creep rate of the alloy at
(c)
The activation enthalpy for creep in
(c)
Answer to Problem 9.5P
The activation enthalpy for creep in
Explanation of Solution
Formula Used:
Write the expression for the ratio of strain rates of
Here,
Calculation:
Substitute
Take log both side,
Conclusion:
Thus, the activation enthalpy for creep in
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Chapter 9 Solutions
Materials Science And Engineering Properties
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- Materials Science And Engineering PropertiesCivil EngineeringISBN:9781111988609Author:Charles GilmorePublisher:Cengage Learning