The S-N Curve component is used to define a material S-N curve for the purpose of calculating fatigue life estimates.
In the S-N Curve component view, you can select one of the following formats from the Curve Type drop-down list:
▪Linear – to define a log-linear S-N curve with or without an endurance limit.
▪Piecewise Linear – to define a piecewise log-linear S-N curve.
▪Data Pairs – to specify the curve directly with pairs of S and N values.
You click on the Properties button to input the data that is appropriate for the curve type.
The S-N curve data that you specify is automatically graphed on the right-hand side of the component view, as shown in the example specification figure below. In this example, a linear curve with an endurance limit is plotted.
Sample S-N Curve
Once an S-N Curve component has been defined, it may be referenced on the Fatigue tab of the Analysis component, where it forms part of the input to a fatigue analysis. The Fatigue tab of the Analysis component groups the S-N curve together with other relevant data required for fatigue life calculations. The remaining inputs pertaining to fatigue, and fatigue analysis in general.