Structural design of a scalable glass with high hardness and crack initiation resistance
Anjali Yadav, Anne Rebecca, Saurabh Kapoor, Yueh‐Ting Shih, Liping Huang, Ashutosh Goel
Abstract
The industry has always strived to design “hard” and “crack-resistant” glass. However, simultaneously realizing these properties in oxide glasses has been rare. Although Al2O3-rich hard and crack-resistant oxide glasses have been reported in the last decade, they exhibit two significant technological challenges that hinder their translation from laboratory to industry: (1) high processing temperatures (>2000 °C) and (2) small glass-forming regions (near eutectic). The present study reports the structural design of a hard and high modulus glass with high crack initiation resistance designed in the peraluminous region of rare-earth containing MgO–Al2O3–B2O3–SiO2 system. The glass can be processed at a temperature ≤1650 °C and exhibits Vickers hardness (Hv) of 7.84 GPa (at 1.96 N load) and indentation crack resistance (ICR) of 26.5 N. These Hv and ICR values are significantly higher than most commercial or non-commercial glasses (prior to thermal tempering, densification near Tg, or chemical strengthening). The glass has been scaled up to successfully produce slabs of dimensions 100 mm × 100 mm × 8 mm at laboratory scale with optical transmission of 90 ± 2 %. The results presented here are scientifically intriguing and have considerable tangible implications, as they pave the path for the design and development of stronger glasses for functional applications.