An investigation of gold/ceramic and gold/glass interfaces

Abstract

Abstract:This paper describes how various characterisation methods can be used to investigate the physicochemical and spectral properties of gold films in contact with glass or ceramic. The interface between the metal and substrate has been given special attention. The examples chosen to illustrate this include: liquid gold films (decorated and fired) or inlayed gold layers on ceramic wares and "sandwich" gold foils between two glass sheets for mosaic application. Characterisation methods include: microanalytical scanning electron microscopy, X-ray diffraction, ion beam analyses (PIXE: particle induced X-ray emission; RBS: Rutherford back-scattering spectrometry), photo-spectrometry and colorimetry. The adhesion mechanism and colour behaviour of the coated objects is discussed.Gold films coated on, or in contact with, oxides (glass or ceramic) have a great number of artistic and technological applications. Gold has been used to decorate ceramic and glass for centuries, e.g. mosaic art and more recently gold films are used in high technology areas to modify surface properties. In most applications, the colour is of great importance, and also the strength and durability of the films. The nature of the adhesion at the interface between coating and substrate is vital in terms of durability. Information about the adhesion mechanism may be obtained by a physicochemical investigation at high resolution.

The characteristics of gold films deposited on ceramic substrate

“…The presence of elements from the substrate in EDS spectra could be due to the fact that, during the firing, a migration phenomenon of those elements to the interface film -substrate, or even in the film, takes places due to a mutual solubility of the film and the substrate (11,12,17,20,21). The migration of the fluxes to the gold film -ceramic interface could explain the fact that some fluxes added by us in the gold compound (V in sample 4) and Ni in sample 5, do not appear on the EDS spectra.…”

“…The bond of the film on the substrate was achieved by the new formed interfacial region (10)(11)(12)17,20,21) consisting of oxide compounds coming from liquid gold compounds and those from the glaze and silicates and Al-Au compounds (20).…”

“…are added in the products, in adequate concentrations (5). The added elements have an important role in film formation, influencing the morphology, the adherence, the colour hues and the resistance to abrasion (6)(7)(8)(9)(10)(11).…”

“…Recently, a very interesting paper presented the results on the investigation of gold/ceramic and gold/glass interfaces (11). The authors determined the composition, morphology and optical properties of gold films deposited on ceramic substrate.…”

“…During the firing of liquid gold, or thermal treatments applied to thermal evaporate gold a migration phenomenon of elements to the interface film -substrate, or even in the film, takes places due to a mutual solubility of the film and the substrate (11,12,17,20,21).…”