Hi @baliasM74U3,
Make sure you have a read/write CC library,
If you go to the content centre editor, right-click on your part in the editor, then select material guide. Click Next, Select Add Materials as New Family Members. Click Next, then select any materials you want available for the bolt. Next, Set any material aliases as needs be. Finally set up the differentiation options. Once done click next and then start. The materials have been added to your part.
The images below show the key steps.
I'll add a screencast once it has processed.




Leo Warren
Autodesk Student Ambassador Diamond
Please accept as solution and give likes if applicable.