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The provided workbench file already has the solution for the problem. We will create another material and assign Alternating Stress Mean Stress and re-run the simulation. Restore the downloaded archive and double click on Engineering Data. In Engineering Data, click on the blank box and enter Al 6061-T6 to create a new material.
Once the new material is created, expand Life and double click on Alternating Stress Mean Stress.
Change the Interpolation to Semi-Log.