Densification in transparent SiO2 glasses prepared by spark plasma sintering

Abstract

Recently, spark plasma sintering (SPS) has become an attractive method for the preparation of solid-state ceramics. As SPS is a pressure-assisted low-temperature process, it is important to examine the effects of temperature and pressure on the structural properties of the prepared samples. In the present study, we examined the correlation between the preparation conditions and the physical and structural properties of SiO2 glasses prepared by SPS. Compared with the conventional SiO2 glass, the SPS-SiO2 glasses exhibit a higher density and elastic modulus, but a lower-height first sharp diffraction peak of the X-ray total structure factor. Micro-Raman and micro-IR spectra suggest the formation of heterogeneous regions at the interface between the SiO2 powders and graphite die. Considering the defect formation observed in optical absorption spectra, reduction reaction mainly affects the densification of SPS-SiO2 glass. Hence, the reaction at the interface is important for tailoring the structure and physical properties of solid-state materials prepared by the SPS technique.

Preparation of transparent Bi2O3‐ZnO‐B2O3 glass by conventional sintering at low temperatures

“…In the literature, the glass compositions that can achieve transparent glass components using the sintering method are mostly pure SiO 2 or predominantly composed of SiO 2 . [19][20][21][22][23][24][25][26][27][28][29][30][31][32] This is because silicate glasses usually have high glass transition temperature (T g ), excellent thermal stability, and are less prone to crystallization during sintering. On the other hand, there is limited literature on the preparation of transparent glasses of low T g by sintering method.…”