Enhancement of damage resistance of transparent Li2O-Al2O3-B2O3 glass by crystallization

Aluminoborate glasses exhibit remarkable crack-resistance properties, rendering them a promising material for cover glasses in portable electronic devices. However, their usage has been hindered by their relatively low hardness. To address this challenge, a parent glass with 11 Li2O-30 Al2O3-55 B2O3-2 TiO2-2 P2O5 (wt%) was prepared using a melt-cast method. Heat treatment at 575 °C yielded a glass-ceramic (G-575) with a Vickers hardness of 6.51 GPa, 40.91 % higher than the parent glass due to structural densification and Li(Al7B4O17) crystalline phase precipitation, improving indentation fracture toughness from 0.97 to 1.79 MPa·m1/2. Additionally, the glass-ceramics demonstrated a visible transmittance of approximately 85 % and a cracking resistance (CR) value of 14.8 N. Scratch tests conducted at a constant force revealed that the comprehensive damage resistance of glass-ceramics surpassed that of the parent glasses, making it a promising cover glass material.