(a)
The critical crack length for alloy steel plate for the applied stress.
(a)
Answer to Problem 52SEP
The critical crack length for alloy steel plate for the applied stress is
Explanation of Solution
Write the expression for the critical length.
Here, the fracture toughness of the material is
Conclusion:
Substitute
Thus, the critical crack length for alloy steel plate for the applied stress is
(b)
The crack length.
The largest allowable initial crack length.
(b)
Answer to Problem 52SEP
The crack length is
The largest allowable initial crack length is
Explanation of Solution
Write the expression for the crack length of the alloy steel plate.
Write the expression for the stress range for the steel.
Here, the maximum compressive stress is
Write the expression for the fatigue life in cycles.
Here, the initial crack length is
Conclusion:
Substitute
Here, the minimum tensile stress is
Substitute
Here, the fatigue constant are
Substitute
The crack length is
The largest allowable initial crack length is
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Chapter 7 Solutions
FOUND.OF MTRLS.SCI+ENGR.(LL)-W/CONNECT
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