A study of (71.5-x)SiO2-xAl2O3-11.5R2O-17RO glass system: Batch reaction process, structure and properties

Abstract Based on the glass system of (71.5-x)SiO2-xAl2O3-11.5R2O-17RO (x = 0.5–6, mole fraction), the batch reaction process, structure and properties such as viscosity, strain point, annealing point, softening point and molten resistivity were studied by substituting the equal mole content of Al2O3 for SiO2. X-ray diffraction (XRD) analysis showed that the reaction of the glass batch was completed at about 1150 °C with all amorphous phase. Differential scanning calorimetry (DSC) test showed that the reaction process of the glass batch was basically the same, but with the increase of the content of Al2O3, the energy required for melting process increased. 27Al Nuclear Magnetic Resonance (NMR) results showed that in the glass network of the system, Al3+ ions basically existed in the form of 4-coordinated [AlO4] tetrahedra as the network formers. Raman spectra showed that the vibration of the glass network with non bridging oxygen decreased with the increase of the substitution amount of Al2O3 for SiO2, while the vibration of bridging oxygen increased gradually, which indicated that the compactness of the network was enhanced, and the vibration peak moved to the lower frequency region. The viscosity, resistivity, strain point, annealing point and softening point of the glass increased with the increasing content of Al2O3, and when the substitution was 4% mole fraction, the strain point could be as high as 550 °C which satisfied for the use of substrates for Copper Indium Gallium Selenium (CIGS) and Cadmium Telluride (CdTe) thin-film solar cells.