A reconstructive polyamorphous transition in borosilicate glass induced by irreversible compaction.

Area of Science:

• Materials Science
• Solid State Physics
• Glass Science

Background:

• Understanding glass behavior under high pressure is crucial for explaining energy dissipation and material damage mechanisms.
• Pressure-induced deformation in glasses, without shear bands or dislocations, involves elastic and inelastic structural changes leading to network compaction.

Purpose of the Study:

• To investigate the pressure-induced structural transformations in sodium borosilicate glass.
• To identify the specific structural changes responsible for inelastic deformation and compaction under pressure.

Main Methods:

• Utilized Raman and Brillouin scattering techniques to probe structural changes.
• Analyzed the formation of specific tetrahedral ring structures within the glass network.

Main Results:

• Observed a pressure-induced reconstructive amorphous-amorphous transition in sodium borosilicate glass.
• Identified the formation of four-membered danburite-type rings composed of BO4 and SiO4 tetrahedra during the transition.
• Demonstrated that compaction is associated with increased structural homogeneity.

Conclusions:

• The inelastic pressure resistance of sodium borosilicate glass is attributed to its Si-O-Si backbone.
• The observed structural transition and subsequent homogeneity are suggested to be universal phenomena in non-crystalline materials.