1. Engineering Mechanics

Fatigue And Fracture — Quiz

Test your understanding of fatigue and fracture with 5 practice questions.

Practice Questions

Question 1

Which term describes the stress amplitude below which a ferrous material can endure an essentially infinite number of load cycles without failure?

Question 2

In Linear Elastic Fracture Mechanics, the critical stress intensity factor K_IC characterizes what material property?

Question 3

In a fatigue crack growth test, da/dN=C(ΔK)^m with C=1×10⁻¹² m/cycle·(MPa√m)^⁻³ and m=3, what is da/dN when ΔK=15 MPa√m?

Question 4

For a material with K_IC=50 MPa√m, what is the critical crack half-length a_c for unstable fracture under σ=100 MPa? Use a_c=$\frac{1}{\pi}(\frac{K_{IC}}{\sigma})^2$.

Question 5

Using the Goodman relation $\frac{S_a}{S_e'}+\frac{\sigma_m}{S_u}=1$ with S_e'=250 MPa, S_u=550 MPa, and mean stress σ_m=100 MPa, what is the allowable alternating stress S_a?