Metal foam relaxation

Dear all,
Hi, I hope you all are fine.
I have a question in order to simulate foam of Gold.
First of all I have a box of Au-Ag mixture.
Now, I want to know that:

  • I have to relax my box and then remove Ag component to generate the foam?
  • I have to create the box, remove the Ag and then start the relaxation step and stuff?

Thanks in advanced