Thermal, Mechanical and Optical Properties of TiO2-doped Sodium Silicate Glass-Ceramics

In this study, local mineral (silica sand) obtained from Hazara division, Khyber Pakhtunkhwa, Pakistan was fabricated into soda-lime silicate glass. Titanium dioxide (TiO2) concentration in the range of 1-3 wt% was added as a nucleating agent to investigate its effect on crystallization phase, density, hardness, thermal expansion coefficient (α), glass transition temperature (Tg), micro hardness and optical bandgap of soda-lime silicate glass. XRD analysis revealed the formation of different crystalline phases such as cristobalite (SiO2), wollastonite (CaSiO2), and rutile (unrefined TiO2, often with iron, F3+) at different processing temperatures. The coefficient of thermal expansion and the optical gap energies varied from 72.5×10–7/K to 77×10–7/K and 3.71-3.93 eV with TiO2 concentration, respectively. The mechanical properties were also in good agreement with those of commercially used glass-ceramics.