M. A. Villegas

Indentation properties of ZrO2–SiO2 coatings on glass substrates

Abstract Sol–gel coatings of different composition in the ZrO 2 –SiO 2 system have been prepared, starting from several precursors (alkoxides and alkylalkoxides). Common soda lime silicate glass slides were used as substrates for coating deposition. The Vickers microhardness, H V , of the coated glass substrates have slightly higher values than that of uncoated glass. Young modulus, E , values for coated glass substrates are higher than that of uncoated glass. To compare the mechanical properties of the samples, the ratio H V / K IC (where K IC is the toughness) has been calculated and the concept of fragility discussed. The fragility of coated samples increases as the ZrO 2 content diminishes and the SiO 2 increases. Both scanning and transmission electron microscopy observations were performed to characterise the textural and microstructural properties of the coatings.