Despite recent advances related to smartphone cover screens, glass still breaks. Brittleness remains the main limitation of glass, as the risk of fracture often raises safety and reliability concerns. Throughout history, glass has been associated with danger and, in fact, it has been estimated that 15-to-30% of injuries are related to broken glass. Here, we explore whether nanoscale phase separation—which is often seen as an undesirable feature of glass—could be used to enhance the resistance to fracture of glasses without affecting their transparency. We adopt a bottom-up modeling approach, wherein (i) high-throughput molecular dynamics (MD) simulations are used to predict the propensity of glasses to phase-separate, (ii) large-scale MD simulations of glass-glass interfaces are conducted to access their mechanical properties, and (iii) continuum peridynamic simulations are used to study the resistance to cracking of phase-separated glasses. Based on this approach, we discuss the effect of stiff and soft nanodroplets on the propagation of cracks in glasses. We predict that nanoscale phase separation can result in a 60% increase in fracture energy as compared to homogeneous glasses.
Authors: Longwen Tang, Mathieu Bauchy