$7-34$ Suppose that we would like a part produ$-$

ced from the acetal polymer shown in

Figure $7-28$ to survive for one million

cycles under conditions that provide for

equal compressive and tensile stresses.

What is the fatigue strength, or maximum

stress amplitude, required? What are the

maximum stress, the minimum stress, and

the mean stress on the part during its use?

What effect would the frequency of the

stress application have on your answers?

Explain.

Figure $7-28$ The S$-$N fatigue curve for an acetal polymer $($for Problems $7-30,7-33,$ and $7-34).$

$7-34$ Suppose that we would like a part produ$-$

ced from the acetal polymer shown in

Figure $7-28$ to survive for one million

cycles under conditions that provide for

equal compressive and tensile stresses.

What is the fatigue strength, or maximum

stress amplitude, required? What are the

maximum stress, the minimum stress, and

the mean stress on the part during its use?

What effect would the frequency of the

stress application have on your answers?

Explain.