Endurance Limit Analysis

Endurance Limit Analysis

The endurance limit, sometimes called the fatigue limit, is the stress level below which the material will never fail due to fatigue, no matter the number of load cycles it is subject to.

Ferrous alloys (such as steel) and titanium alloys have a definite endurance limit. Other common structural materials, such as aluminium, do not have a prescribed endurance limit, and will fail eventually, even if the experienced stresses are very low. For these materials, the term fatigue strength is used as an endurance limit does not exist.

The endurance limits are represented by the horizontal part of the S-N curve (https://www.fea-solutions.co.uk/s-n-curves/). Typical values for the endurance limits of steels are 50% of the ultimate strength of the particular grade, up to around 290MPa.

The endurance limit of a material is used as a design point for a component. If the stresses experienced do not exceed this value, the component will have an unlimited fatigue life.

The concept of endurance limit has been around for over 100 years. Recent research has however indicated that all materials will eventually fail due to fatigue, if enough load cycles are performed.

Please call us today on +44 (0)1202 798991 for any engineering analysis requirements you might have.