Concept explainers
a)
Constant for the hall- Petch equation has to be determined.
a)
Answer to Problem 58AAP
Constants for the hall- Petch equation is
Explanation of Solution
Hall-Petch Equation:
The Hall-Petch equation describes the strength of the metal as a combination of frictional stress and a factor (
Write the Hall-Petch relation as given as follows:
Here, the yield stress of the metal is
Conclusion:
Substitute 185 MPa for
Substitute 140 MPa for
Substitute equation (II) in equation (III).
Substitute
Thus, constants for the hall- Petch equation is
b)
Grain size for the strength of 220 MPa has to be determined.
b)
Answer to Problem 58AAP
Grain size for the strength of 220 MPa is
Explanation of Solution
Hall-Petch Equation:
The Hall-Petch equation describes the strength of the metal as a combination of frictional stress and a factor (
Write the Hall-Petch relation as given as follows:
Here, the yield stress of the metal is
Conclusion:
Substitute 140 MPa for
Thus, grain size diameter to obtain a 220 MPa strength is
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Chapter 6 Solutions
Foundations of Materials Science and Engineering
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