Estimating the metal-ceramic van der Waals adhesion energy

We invoke the Lifshitz theory of van der Waals forces to derive a simple, analytical expression for the adhesion across a planar metal-ceramic interface. The van der Waals energy is conveniently expressed as a function of readily accessible bulk properties of the respective materials. Application to several non-reactive metal-sapphire systems shows the predicted van der Waals energy to provide a good lower-bound estimate of the measured adhesion energy. Apart from platinum and palladium, where strong metal-aluminium interactions have been predicted, adhesion energies in noble-metal systems are well accounted for by van der Waals interactions alone. Not surprisingly, adhesion in the more chemically active metals exceeds the van der Waals energy.