The adhesion of the overmolding plastic with the substrate is of course usually a relevant specifications in many applications. The issue is that the adhesion of a molten plastic with metal is intrinsically close to 0, broadly speaking. Depending on the nature of the polymer and those of the metal substrate, a specific treatment might be applied to trigger the adhesion.
Some internal studies have shown that a good adhesion between our Tecnoflon FKM and metal can be obtained during molding and curing provided a specific metal surface treatment and the use of a primer. This is well documented in this presentation.