Title

Viscosity, Relaxation And Elastic Properties Of Photo-Thermo-Refractive Glass

Keywords

Rheology; Silicates; Structural relaxation; Ultrasonic relaxation; Viscosity

Abstract

Viscometry, ultrasonic echography and mechanical spectroscopy were applied to explore the thermo-mechanical properties of a photo-thermo-refractive (PTR) glass. Newtonian shear viscosity and ultrasonic velocity were used to determine the Maxwell time of structural relaxation. Two fast relaxation modes are found in PTR glass below glass transition temperature, which are attributed to alkali and mixed cation mobility. Respective activation energies, Eγ = 72 ± 4 kJ mol-1 and Eβ = 117 ± 4 kJ mol-1, are considerably lower than that of viscous flow at the glass transition Eα ≈ 465 kJ mol-1 as quantified from mechanical spectroscopy. Decoupling ratios of Eγ/Eα = 0.155 and Eβ/Eα = 0.255 are similar to those of sodium trisilicate glass but at considerably longer timescales. These observations imply that β- and γ-relaxations are delayed as local structural arrangements are more complex for the multi-component PTR glass. © 2008 Elsevier B.V. All rights reserved.

Publication Date

1-15-2009

Publication Title

Journal of Non-Crystalline Solids

Volume

355

Issue

2

Number of Pages

126-131

Document Type

Article

Personal Identifier

scopus

DOI Link

https://doi.org/10.1016/j.jnoncrysol.2008.10.002

Socpus ID

58149125272 (Scopus)

Source API URL

https://api.elsevier.com/content/abstract/scopus_id/58149125272

This document is currently not available here.

Share

COinS