Structure of Metal Substrates - Metallography

To understand some of the problems associated with the achievement of good rubber to metal bonds it is worth considering some of the scenarios involving the atomic structure of metals at their surfaces. 

A metal, or an alloy of metals, naturally assumes a crystalline structure and it is likely that it will have a regular shape and lattice structure, with some voids in the interstices. As with rubber compounds, metals are formed by mixing a number of components together which disperse relative to each other, but never, except maybe in the case of pure metals, become one totally uniform uninterrupted phase. Most metals are used as some type of alloy, i.e.. 

Although as a rubber to metal bonder one is not very interested in the metals strucmre within the mass of the metal, one must consider what is happening in and on its surface layers. 

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