Bonded contact can tolerate some amount of gap or penetration between the faces that it is asked to bond. Create the contact, mesh the part and insert a Contact Tool and Generate Initial Contact Status. You want to see the contact is Closed. If it is not, edit the contact and set the Pinball Radius to a number where the two faces will be inside the ball. Then you will get closed contact.  During the solution, a bonded contact will hold the faces with the pre-existing gap or penetration.  This is different from Frictional Contact, which will push penetrating faces away at the beginning of the solution.