The development of a rapid quenching device for the study of the dependence of glass structure on fictive temperature

We have constructed a rapid quenching device with an estimated quench rate of 1x10(5) degrees C/s in order to explore the structural changes of glasses formed with varying quench rates. This apparatus quenches the sample in an inert atmosphere and recovers 100% of the sample, allowing the study of small (similar to 20-50 mg), isotopically enriched samples that can greatly facilitate nuclear magnetic resonance (NMR) studies of nuclei with low natural abundance (such as O-17 and Si-29). An O-17-enriched Ca-boroaluminosilicate glass was formed with a high quench rate using this apparatus, and a clear increase in the amount of nonbridging oxygens with increasing quench rate was observed. Additionally, B-11 NMR spectra of E-glass samples formed with a wide variety of fictive temperatures showed a decrease in the proportion of B-[4] in E-glass with increasing fictive temperature, in accordance with previous studies. The changing proportion of B-[4] present in the E-glass sample with changing quench rate was used as a rough method of confirmation of the calculated quench rate. (c) 2006 American Institute of Physics.