Tailoring the Mechanical Properties of Metaluminous Aluminosilicate Glasses by Phosphate Incorporation

Abstract

The characterization of aluminosilicate glasses is highly relevant in geosciences and for engineering applications such as reinforcement fibers or touchscreen covers. The incorporation of phosphate as a third network-forming species into these glasses offers unique opportunities for fine-tuning glass properties via changes in glass structure and polymerization. In this work, we studied melt-quenched aluminosilicate glasses within the system SiO 2 -Al 2 O 3 -Na 2 O-P 2 O 5 with 50-70 mol% SiO 2 and up to 7.5 mol% P 2 O 5 . All glasses were metaluminous (Al:Na = 1) in order to maximize the degree of polymerization. Increasing the phosphate content at the expense of NaAlO 2 led to reduced glass polymerization and density, resulting in a decrease in elastic moduli and hardness and an increase in strain-rate sensitivity. When increasing the silica content by substituting SiO 4 for AlO 4 tetrahedra, network polymerization remained mostly unchanged, as confirmed by nearly constant hardness. Densification upon indentation was analyzed by Raman spectroscopy and finite element analysis. We find that the elastic properties and hardness of metaluminous phospho-aluminosilicate glasses are governed by changes in density and network polymerization. Other mechanical properties underlie more complex changes in glass structure.

Influence of Vanadium on Optical and Mechanical Properties of Aluminosilicate Glasses

“…In the polymerized NA66.18 glass, however, V introduces weak points in the strong and very homogeneous (Si, Al) network. The behavior of V here seems to be very similar to the one of another network former, P in aluminosilicate (Mysen and Richet, 2005;Grammes et al, 2020). The DiAn series shows that the evolution of Tg is perfectly linear with increasing V content (see Table 1).…”

A modified random network model for P2O5–Na2O–Al2O3–SiO2 glass studied by molecular dynamics simulations

“…The simulated densities are shown in Table 1 and ranges from 2.37 to 2.54 g cm À3 , consistent with previous reported experimental result. 31,35,36 Compared with initial densities, the deviations are less than 2% and 1% in NA and PNA series, respectively, which is quiet reasonable for MD simulations. 31 3 Results…”

Surface damage resistance and yielding of chemically strengthened silicate glasses: From normal indentation to scratch loading

“…29 Although the universal validity of these simplistic correlations has very recently been questioned, 59 the atomic packing density and network dimensionality have frequently been utilized as useful metrics to describe compositional variations in Poisson's ratio for a variety of silicate 48,[60][61][62][63][64] and aluminosilicate glasses. [65][66][67] The observed increase of with increasing molar ratio R may originate from the parallel increase of C g upon progressive substitution of Na 2 O by K 2 O. The slight offset in Poisson's ratio between the series of mixed sodium-potassium silicate and aluminosilicate glasses may furthermore reflect the underlying differences in network dimensionality and atomic packing efficiency between these two glass systems.…”

“…The values of strain-rate sensitivity for the asmelted sodium-potassium silicate and aluminosilicate glasses are located within the typical range of strain-rate sensitivities reported for silicate glasses. 35,48,67,73,76,77 Modifying the molar ratio R results in almost negligible changes of m, with a maximum difference of about 0.001 (SLS series) and 0.002 (AS series), respectively. This result compares very well to the extent of strain-rate sensitivity alterations reported for a series of metaphosphate glasses containing pairs of different alkaline species (Mg 2+ , Ca 2+ , and Sr 2+ ) in varying molar ratios.…”