Densified silica glass after shock compression

Abstract

Silica glasses were repeatedly densified by multiple shock reverberations in stainless-steel capsules. The limit of increase in density was about 2.47 Mg/m3 after the first shock loading. Further increase in density was observed after duplicate shock loading, but limited at about 2.55 Mg/m3. Triplicate shock loading was not so effective for the increase in density. The Raman spectra of recovered silica glasses had characteristics of densified silica glass with much higher density. The remarkable one was the enhancement of the line at 605 cm−1 called the D2 line, which was one of two narrow lines peculiar to the Raman spectrum of silica glass.

Size dependence of elastic mechanical properties of nanocrystalline aluminum

“…This is in good agreement with previous findings for this amorphous material. 9,[15][16][17][18]20 B. Silica glass nanowires: Surface effects When a silica NW is carved out of the bulk silica glass, the surface-to-volume ratio significantly increases, thus the surface structure will likely be different from its inner core structure and bulk counterpart, as reported recently. 10 Figure 2(a) illustrates how the radial density distribution was calculated in a NW.…”

“…As a typical disordered material, the response of bulk silica glass to mechanical loading has been demonstrated to be different from that of crystalline polymorphs both experimentally and theoretically. [15][16][17][18][19][20] Previous simulations have correlated the elastic-to-plastic mechanical response of bulk silica glass with structural transformations determined via ring size analysis, where ring size, n, is the shortest loop formed by n Si-O bonds. 19,20 The ring size distribution of bulk silica has been shown to have an average ring size of six (n ¼ 6) and the number of rings smaller and larger than this average drops off rapidly.…”

Measurements of density distribution around Vickers indentation on commercial aluminoborosilicate and soda-lime silicate glasses by using micro Raman spectroscopy

“…The ratio of the intensity of D 1 to that of D 2 is used to determine fictive temperature [15][16][17] which corresponds to density. It is also known that the wavenumber of the D 2 line for the samples densified under hydrostatic pressure has a relationship with the relative density Δρ/ρ [18], so Perriot et al [7] used this peak wavenumber to obtain a density distribution map around the indentation in silica glass. Although the D 1 nor D 2 lines cannot be recognized in Glasses C and D, the main peaks around 500 cm − 1 or 560 cm − 1 shift with increasing hydrostatic pressure.…”

Raman Microspectroscopic Characterization of Amorphous Silica Plastic Behavior

“…The residual density evaluated through this relation accounts for both irreversible and elastic densification due to residual elastic strain. However, several works [22,27] evidenced that the D 2 line position is only marginally sensitive to residual elastic strains.…”