Sol–gel derived SiO₂–B₂O₃–Na₂O–ZnO–Al₂O₃ glass powder for glass-based composite

The glass powder with a relatively complicated composition of 64.02SiO2–10.05B2O3–7.84Na2O–14.07ZnO–4.02Al2O3 (in wt.%) was first synthesized via sol–gel route. The optimal synthesis conditions for the amorphous gel are obtained. The glass transition temperature [Formula: see text] of xerogel was detected as 552[Formula: see text]C and the glass network structure formed by the [SiO4], [BO4] and [AlO4] units were confirmed by the Fourier Transform-Infrared Spectroscopy (FT-IR). The phase structure and morphologies of glass powder were characterized by X-ray diffractometer (XRD) and Field Emission-Scanning Electron Microscope (FE-SEM), the xerogels and sol–gel glasses exhibit amorphous phase when the heat-treatment temperature increases from [Formula: see text]C to [Formula: see text]C. The prepared glass powder with high specific surface areas and a large amount of pores contribute to the synthesis of a composite of glass-mullite-[Formula: see text]-eucryptite at a relatively low sintering temperature of [Formula: see text]C, which present a relatively low coefficient of thermal expansion (CTE) and high mechanical strength.