ISSN:
1573-4803
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract In the systems R2O-WO3 (R=Li, Na, K), the glass-forming region was extended by use of the rapid quenching technique combining a thermal-image furnace with a twin roller. The infra-red spectra revealed that the Li2WO4 glass contains no condensed macro-anions but only discrete ions of Li+ and WO 4 2− . The glass transition temperature (T g) and the crystallization temperature (T c) were determined.T g is affected very slightly by the type of alkali cations, whereas it is decreased with increase in the alkali oxide content. More than oneT g was observed in Li2O-WO3 glasses, which is due to the formation of metastable phases. The conductivity of glasses containing the same amount of alkali oxide (of different types) increased with decrease in the radius of the alkali cation. Electrochromism was observed in the glasses with R=Li, Na; the electric field required for colouration is lower than that in WO3 films. The electro-colouration is due to HxWO3 formed in the glass matrix by the double injection of protons and electrons.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00752202
