An S-N curve is a graphical representation of the cyclic loading, ploted as stress amplitude versus the number of cycles the material goes through before it fails. The greater the number of cycles in the loading history, the smaller the stress the material can withstand without failure.
Dewesoft offers an editor which allows you to add or modify S-N Curves. The database is located in the system folder. To change the database location go to Settings -> Files and folders:
The S-N curves editor can be found in Options -> Editors -> S-N Curves.
When you enter the editor, the following window appears:
Here you can add and delete S-N curves. You can also modify the existing curves to match the stress specifications of your materials.
In the S-N curves editor you can also find standard S-N curves from the Eurocode 3 standard.