Silicate based glasses

Glass-Ceramics Based on Silicate Crystals. The principal commercial glass-ceramics fall into this category. These can be grouped by composition, simple siUcates, fluorosiUcates, and aluminosihcates, and by the crystal stmctures of these phases. 

Elastic modulus Up to the fracture stress, glass behaves, for most practical purposes, as an elastic solid at ordinary temperatures. Most silicate-based commercial glasses display an elastic modulus of about 70GNm", i.e. about 1/3 the value for steel. If stress is applied at temperatures near the annealing range, then delayed elastic effects will be observed and viscous flow may lead to permanent deformation. 

Binary silicate-based glasses, x-ray photoemission spectroscopic... 

Boron, oxide additives in silicate-based glasses, x-ray photomission spectroscopic spectra. 151/ Bridges... 

Amperometric cells, sensors using, 22 271 Amperometric measurements, 14 612 Amphetamine, 3 89-90 Amphibole asbestos, 1 803 3 288 crystal structure, 3 297-298 exposure limits, 3 316 fiber morphology, 3 294-295 silicate backbone, 3 296 Amphibole potassium fluorrichterite, glass- ceramics based on, 12 637 Amphiphile-oil-water-electrolyte phase diagram, 16 427-428 Amphiphile-oil-water phase diagrams,... 

MMVF are synthetic fibers with glasslike structures. The term usually refers to silicate-based glass fibers, because these compositions form the largest volume of fibers produced. However, in addition to fiberglass and fused silica (Si02), there are other amorphous fibers used in commerce alumina (AI2O3) and silica combinations, rock and slag wool, as well as fibers with nonsilicate compositions such as carbon. Many of these amorphous fibers have proprietary names. 

Lashtchenova, T. N. Stefanovsky, S. V. 19981). Titanium-silicate based glass-crystalline waste-forms. In Choudhary, M. K., Huff, N. Y. Drummond III, C. H. (eds) Proceedings of the XVIII International Congress on Glass. San-Francisco, CD-ROM. 

The mechanical properties of silicate- based glasses have been extensively studied due to their widespread use as containers, reinforcing fibers, and optical fibers. Consequently, there is a wealth of information on the influence of many variables on the mechanical properties of these glasses. We shall concentrate on (a) composition and temperature effects on modulus and strength and (b) an important method of strength enhancement in glass fibers. 

Chemical Properties. The chemical durability is a function of the durability of the crystals and the residual glass. Generally, highly siliceous glass-ceramics with low alkali residual glasses, such as glass-ceramics based on quartz and (3-spodumene, have excellent chemical durability and corrosion resistance similar to that obtained in borosilicate glasses. 

Oxides. Although not widespread commercially, glass-ceramics consisting of various oxide crystals in a matrix of siliceous residual glass offer properties not available with more common silicate crystals. In particular, glass-ceramics based on spinels and perovskites can be quite refractory and can yield useful optical and electrical properties. 

X-Ray Photoemission Spectroscopy (XPS) Study of Uranium, Neptunium, and Plutonium Oxides in Silicate-Based Glasses... 

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