How can I find a suitable value for the Safety Factor?

The entered Safety Factor and with it the calculated Stress Goal from the material strength is the target of the optimisation. At the end of the optimisation all material should be evenly loaded with this value which always equals a Failure Criterion value of 1.

The occurring stress highly depends on the applied loads. In most cases a Safety Factor of 1 and with it the maximum strength of the material is not a suitable value. If the Stress Goal is assumed too high (Safety Factor too low) and the loads aren’t able to create stresses accordingly, all the material will be reduced.

For the Safety Factor an educated guess should be done. If you have no clue which value is a good starting point for your model, just start with a high value. Have a look at the approximated stresses or on the Failure Criterion values in your first iterations, terminate the simulation and modify the value accordingly. The calculation of the first iterations should only take a few minutes.