Structural Equilibria in Silicate Glass Melts Investigated by Raman Spectroscopy

• Published in: Journal of the American Ceramic Society Vol. 89; no. 1; pp. 89 - 95
• Main Authors: Yano, Tetsuji, Shibata, Shuichi, Maehara, Terutaka
• Format: Journal Article
• Language: English
• Published: Malden, USA Blackwell Science Inc 01.01.2006; Blackwell; Wiley Subscription Services, Inc
• Subjects: Applied sciences; Building materials. Ceramics. Glasses; Ceramics; Chemical industry and chemicals; Entropy; Exact sciences and technology; Glass; Glasses; Manufacture; Materials science; Mathematical analysis; Melting; Melts; Phase separation; Physical properties; Silica; Silicates; Spectrum analysis; Tetrahedrons; Alkali metal Silicates; Theoretical study; Entropy; Glass structure; Glass melt; High temperature; Experimental study; Raman spectrum; Thermodynamic equilibrium
• ISSN: 0002-7820; 1551-2916
• DOI: 10.1111/j.1551-2916.2005.00815.x

Structural equilibria of alkali silicate glasses and melts are investigated based on the Qn fractions (n=number of bridging oxygen in SiO4 tetrahedron) obtained from high‐temperature Raman spectra. A mathematical treatment of the entropy of mixing, ΔSmix, of structural groups of Qn is conducted and applied to the investigation of phase transformation and phase separation. Characteristics of Qn traces and the counter‐map of ΔSmix on Qn diagram are found to possess useful information to understand their mechanisms. An extended Qn diagram is also proposed to understand the melt structure and properties for the wide composition range.