ABSTRACT
The literature reveals significant interest in zirconia coatings prepared using alkoxide-based sol-gel processes. This paper reviews the achievements of our research group in this area. The chemistry of the processes we have used is briefly described. Coatings were prepared on both glass and metallic substrates by dip coating followed by firing under various controlled conditions. Characterisation of all stages of the sol-gel process has been undertaken. Particle size analysis of the species in solution has been performed using static light scattering. The transformation of the gel has been studied by thermal analysis and X-ray diffraction (XRD). The final coatings and coating/substrate interactions have been characterised by XRD, scanning Auger microscopy (SAM), scanning electron microscopy (SEM), Rutherford backscattering spectrometry (RBS) and precision ultra-microhardness. Information on cracking and adherence of the coating will also be presented. Discussion will be centred on the effect of variation of the solution and processing parameters on the characteristics of the final coatings.
