Raman microspectroscopic characterization of amorphous silica plastic behavior

TL;DR

This study employs Raman microspectroscopy to analyze amorphous silica's plastic behavior, revealing densification-induced hardening and challenging existing pressure-dependent yield models, thus paving the way for improved constitutive laws.

Contribution

It introduces a novel correlation between Raman spectra and density to map residual densification and demonstrates densification-induced hardening in amorphous silica.

Findings

Densification correlates with specific Raman spectral features.

Densification induces hardening not explained by previous models.

New insights enable more accurate constitutive modeling of silica.

Abstract

Raman microspectroscopy was used to characterize amorphous silica plastic behavior. Using a correlation between Raman spectrum and density, a map of the local residual indentation-induced densification is obtained. The existence of a densification-induced hardening is also evidenced through a diamond anvil cell experiment. Such observations are not accounted for by the previously proposed hardening-free pressure-dependent yield criterion based on indentation curves. These results open the way to more accurate description of a constitutive law for amorphous silica.