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Title: Case II diffusion of water in Na 2 O–3SiO 2 glass: Constant tensile stress gradient at the diffusion interface
Abstract Some polymers and oxide glasses exhibit unusual diffusion of liquid or gas, with the depth of diffusion exhibiting a linear increase with time, instead of normal square root of time dependence. There have been many models, but very few experimental data that can help clarify the cause of the phenomenon's existence in glass. Residual stress in sodium trisilicate glass (Na2O–3SiO2) samples was characterized following Case II water diffusion at 80°C in a saturated water vapor environment. The surface‐swelled layer of the glass was removed by dissolving it in water, and birefringence of the newly revealed surface layer was measured. The presence of a constant negative tensile stress gradient was revealed by indicating that Case II diffusion in sodium trisilicate glass originates from this stress gradient, which overwhelms the more typical Fick's law concentration‐dependent flux.  more » « less
Award ID(s):
1713670
PAR ID:
10472994
Author(s) / Creator(s):
;
Publisher / Repository:
American Ceramic Society and Wiley Periodicals LLC
Date Published:
Journal Name:
International Journal of Applied Glass Science
Volume:
14
Issue:
2
ISSN:
2041-1286
Page Range / eLocation ID:
330 to 337
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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