ASTM defines fatigue life, Nf, as the number of stress cycles of a specified character that a specimen sustains before failure of a specified nature occurs.
One method to predict fatigue life of materials is the Uniform Material Law (UML). UML was developed for fatigue life prediction of aluminum and titanium alloys by the end of 20th century and extended to high-strength steels and cast iron. For some materials, there is a theoretical value for stress amplitude below which the material will not fail for any number of cycles, called a fatigue limit, endurance limit, or fatigue strength.
Read more about this topic: Fatigue (material)
Famous quotes containing the words fatigue and/or life:
“He is asleep. He knows no longer the fatigue of the work of deciding, the work to finish. He sleeps, he has no longer to strain, to force himself, to require of himself that which he cannot do. He no longer bears the cross of that interior life which proscribes rest, distraction, weaknesshe sleeps and thinks no longer, he has no more duties or chores, no, no, and I, old and tired, oh! I envy that he sleeps and will soon die.”
—Albert Camus (1913–1960)
“You want to prepare your child to think as he gets older. You want him to be critical in his judgments. Teaching a child, by your example, that there’s never any room for negotiating or making choices in life may suggest that you expect blind obedience—but it won’t help him in the long run to be discriminating in choices and thinking.”
—Lawrence Balter (20th century)