peteroznewman
Bbp_participant

Myles is correct, using Shared Topology maintains separate bodies that can each be assigned a unique material.  In that way, it is different to using a CAD unite command to merge mulitple bodies into a single body.  Shared Topology creates a multibody part.

When using Linear elements, make sure to use at least 4 elements across the thin dimension of any body in the part.