Influence of phase separation microstructure on the mechanical properties of transparent modifier-free glasses

Self-crystallization mechanism of CsPb(Cl/Br)3 in tellurite glass-ceramics controlled by phase separation

“…As well-known, influencing the cations competing with oxygen in the glass network to realize phase separation is the most common method to achieve self-crystallization in glass by controlling the proportion of glass formers or introducing modifiers. 10,11 Besides, when the electron potential (f = Z/r) of introduced cations is similar to that of original cations in the glass network, phase separation is more likely to occur. For example, in 2020, Wang et al adjusted the concentration of LiBr to aggravate the phase separation, and then the CsPbBr 3 PeQDs were self-crystallized in borosilicate glass, which provides an energysaving method to obtain CsPbBr 3 PeQDs.…”

Tuning the hardness and crack resistance through liquid–liquid phase separation in an aluminosilicate glass

“…However, the mechanical properties of phase-separated glasses have not been sufficiently studied, with only a few reports available. 4–9 For example, through heat treatment at 520 to 680 °C for 0 to 80 hours, a phase-separated sodium borosilicate glass with the molar percent composition 60SiO 2 ·37B 2 O 3 ·3Na 2 O was prepared to investigate the effect of its microstructure on mechanical properties. 7 Confirmed by the TEM-replica micrograph, these phase-separated glasses are composed of a droplet phase enriched in Na 2 O and B 2 O 3 embedded in a matrix phase enriched in silica.…”

“…As a feasible strategy, recently, by microstructural tailoring, LLPS has been proposed as a promising route to improve the mechanical performances of glasses while simultaneously maintaining their merit of good optical transparency. 4,5 Based on the quantitative analysis of various contributions to the fracture energy according to peridynamics simulations, Tang et al 4 found that nano-scale phase separation can significantly enhance the toughness of glasses and the extent of this enhancement is controlled by the balance among the propensity for crack deflections, the effective cohesion of the glass obtained by LLPS, the existence of plastic energy dissipation, and the roughness of the crack surface. Taking soda-lime-silica glasses with embedded glassy nanoscale silica droplets as an example, further atomic-scale molecular dynamics simulations by Smedskjaer et al 6 indicated that crack propagation is impeded by crack arrest, crack deflection and diversion, and stress field alteration when a propagated crack encounters the interfaces of two separated glassy phases, thus leading to the enhancement of fracture toughness.…”

“…In contrast to this observation, a slight increase in hardness was found recently through heat treatment for 4 hours at different temperatures in a modifier free 27.7B 2 O 3 Á a State Key Laboratory of Silicate Materials for Architectures, Wuhan University of 58.4SiO 2 Á3.9Al 2 O 3 Á10P 2 O 5 (in mol%) glass. 5 The increase in the 4-point bending strength with the extension of heat treatment time is ascribed to the gradually increased stress formed during cooling, which is due to the difference of thermal expansion coefficients between the separated matrix and droplet phases. However, the cause of the drop or rise in hardness is not so clear.…”

Residual stress versus microstructural effects on the strength and toughness of phase‐separated PbO–B2O3–Al2O3 glasses

“…This discussion is not new, and the literature brings several studies on the mechanical properties of oxide glasses showing LLPS, such as the Li 2 O–B 2 O 3 –SiO 2 , 6 Na 2 O–B 2 O 3 –SiO 2 , 6–8 Na 2 O–CaO–SiO 2 , 9 B 2 O 3 –SiO 2 , 9,10 PbO–B 2 O 3 , 11–13 K 2 O–Li 2 O–SiO 2 , 14 and B 2 O 3 –SiO 2 –Al 2 O 3 –P 2 O 5 15 glasses. Recently, these studies have resurfaced in the field of computer simulations to predict the mechanical properties of phase‐separated glasses 16,17 .…”