Adherence controlling elements in ceramic-metal systems. I. Precious alloys.

Elemental analysis of two precious alloyceramic systems revealed the accumulation of Sn atoms within the interaction zone of couples subjected to a range of metal oxidation time; and varying total firing times. The source of Sn atoms which accumulated within the interaction zone was the opaque porcelain layer which contained an initially higher Sn concentration than the alloy. It is hypothesized that SnO2 provides continuity of electronic structure between alloy and ceramic structures and is a primary factor in controlling ceramic-metal adherence.