Sintering behaviour of nanoceramic coatings

Abstract Densification of sol–gel derived thin nanoceramic coatings by laser irradiation and furnace treatment is discussed. Deposition of the zirconia coatings is by means of spin coating. Sintering of the coated layer is observed using a number of different measuring techniques, with special attention paid to densification behaviour and to grain growth in the coating layer using scanning electron microscopy and ellipsometry. The different crystal phases observed are also examined. During sintering at constant temperature a change in the sintering behaviour with time is observed at most temperatures. A theory is presented to explain this observed change in sintering behaviour of the sol–gel layer. Both the initial fast sintering (for all sintering temperatures) and the final slow sintering (at only the higher sintering temperatures) are explained.