Understanding Fatigue Failure and S-N Curves @TheEfficientEngineer

Uploaded June 2019 | Updated September 2026, 1 week ago

Fatigue failure is a failure mechanism which results from the formation and growth of cracks under repeated cyclic stress loading, leading to fracture. It can result in failure at stress levels well below the material yield or ultimate strengths.

In this video I discuss the mechanisms behind fracture, and how S-N curves can be used to predict the fatigue life of a component.

I also discuss the effect of having a tensile mean stress, and how we can use techniques like the Rainflow counting method and Miner's rule to consider complex cyclic stresses.

The Efficient Engineer is a channel aimed at mechanical and civil engineers. The mission is to simplify engineering concepts, one video at a time!

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$Understanding Fatigue Failure and S-N Curves Fatigue failure is a failure mechanism which results from the formation and growth of cracks under repeated cyclic stress loading, leading to fracture. It can result in failure at stress levels well below the material yield or ultimate strengths. In this video I discuss the mechanisms behind fracture, and how S-N curves can be used to predict the fatigue life of a component. I also discuss the effect of having a tensile mean stress, and how we can use techniques like the Rainflow counting method and Miners rule to consider complex cyclic stresses. The Efficient Engineer is a channel aimed at mechanical and civil engineers. The mission is to simplify engineering concepts, one video at a time! Follow me on Twitter: https://twitter.com/efficiengineer Support the channel on Patreon: https://www.patreon.com/efficientengineer$

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