SiO2/B2O3 glass formers effect on transparency and mechanical properties of soda-lime borosilicate glasses for automobile applications

Glass composition (64-y)SiO2 -yB2O3 -16Na2O -12CaO -2Al2O3 -6MgO (y = 2, 4, and 6 mol%) was prepared by the melt-quench technique. The X-ray diffraction spectra confirmed the amorphous nature of the samples. The hardness, fracture toughness, and coefficient of thermal expansion are increased with the addition of B2O3 in place of SiO2. Fourier transform infrared and Raman spectroscopy investigations revealed a structural change as the increment of Q3 units on the cost of Q2 and Q1 units. The optical band gap and the Urbach energy do not follow any trend due to the mixed glass former effect. The highest optical band gap is found at nearly 3.95 eV for the 62S-2B sample. The transparency and hardness are found to be comparable to commercially available windshield glasses i.e. 88%-86% and 6.03-6.94 GPa, respectively. Nevertheless, the present findings can be used to optimize glass composition for automobile applications.

Automated summary

Glass composition (64-y)SiO2 -yB2O3 -16Na2O -12CaO -2Al2O3 -6MgO (y = 2, 4, and 6 mol%) was prepared by melt-quench technique. The addition of B2O3 increased the hardness, fracture toughness, and coefficient of thermal expansion. Structural change was observed as Q3 units increased at the expense of Q2 and Q1 units. Optical band gap and Urbach energy did not show a specific trend due to the mixed glass former effect. The highest optical band gap was found in the 62S-2B sample. Transparency and hardness were comparable to commercially available windshield glasses. These findings can be used to optimize glass composition for automobile applications.