Crack-Tip Structure in Soda-Lime-Silicate Glass

Published

March 1, 2005

Author(s)

J -. Guin, Sheldon M. Wiederhorn, Theo Fett

Abstract

The topology of crack tips in soda-lime-silicate glass was investigated using atomic force microscopy. Studies were conducted on cracks that were propagated in water and then subjected to stress intensity factors either at or below the crack growth threshold. Such exposure resulted in long delays to restart crack growth after increasing the stress intensity factor to higher values. After breaking the fracture specimen in two, the upper and lower fracture surfaces were mapped and compared using atomic force microscopy. Fracture surfaces matched to an accuracy of better than 1 nm normal to the fracture plane and 5 nm within the fracture plane. Crack tip displacements that developed after a critical holding time depended on the applied stress intensity factor. Displacements were independent of distance from the crack tip, and increased with holding time, approaching an upper limit of about 25 nm for very long times. Despite the crack tip displacement, cracks were ogee-shaped at their tips and appeared to be sharp. We discuss our results in terms of a hydronium ion-alkali ion exchange along the crack surfaces and corrosion of the glass surface by hydroxyl ions near the crack tip.

Citation

Journal of the American Ceramic Society

Volume

88

Issue

No. 3

Pub Type

Journals

Keywords

atomic force microscopy, crack tip structure, fracture, glass, subcritical crack growth

Citation

Guin, J. , Wiederhorn, S. and Fett, T. (2005), Crack-Tip Structure in Soda-Lime-Silicate Glass, Journal of the American Ceramic Society (Accessed December 26, 2024)