Effect of Organic Liquids on Crack Propagation in Glass
NAVAL RESEARCH LAB WASHINGTON DC
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A study was conducted on the effect of straight chain organic alcohols and alkanes having chain lengths between 5 and 16 carbon atoms on crack propagation in various glasses. The test was a modification of the double cantilever beam technique. Tests performed in the alcohols yield plots of crack velocity versus stress intensity factor K which were tri-modal, similar to those for glass tested in N2 gas of varying relative humidity. Experiments in the alkanes except for pentane yielded similarly shaped curves. Crack velocities in the two lowest K regions were independent of alcohol chain length and were controlled by water dissolved in the alcohol, fitting a model derived by Wiederhorn for the effect of water on crack propagation. It was shown that the activation energy for crack growth suggested that alkali ion diffusion in the glass controlled crack growth rates. There was no systematic effect of glass composition within the soda-lime-silica system or in fused silica, but crack velocities at a given K in a 3Ba.5SiO2 glass were higher under all conditions than those in soda-lime glasses.
- Ceramics, Refractories and Glass