Intergranular films at metal-ceramic interfaces

We report here theoretical calculations indicating the stability of equilibrium nanometer-thick films at metal-ceramic interfaces. Hamaker coefficients were calculated for metal-ceramic interfaces in the presence of a SiO2-based film, which indicated that a stronger attractive force is expected for intergranular films at metal-alumina interfaces, relative to alumina grain boundaries, correlating to the experimentally measured film thickness presented in part I of this report. From the combination of an attractive van der Waals force together with steric repulsion due to ordering induced in the amorphous film, a force balance can be obtained leading to the formation of equilibrated films at metal-ceramic interfaces.