Lithium silicate glass-ceramics

Lithium oxide(s), 15 134, 141 Lithium perchlorate, 3 417 15 141-142 dessicant, 3 360 in lithium cells, 3 459 Lithium peroxide, 15 142 18 393 Lithium phosphate, 15 142 Lithium-polymer cells, 3 551 in development, 3 43 It Lithium primary cells, 3 459-466 Lithium production, 9 640 Lithium products, sales of, 15 121 Lithium salts, 15 135-136, 142 Lithium secondary cells, 3 549-551 ambient temperature, 3 541-549 economic aspects, 3 551-552 high temperature, 3 549-551 Lithium silicate glass-ceramics, 12 631-632... 

M. R. DeSocio, in Effect of Potassium Content on the Properties of Lithium Silicate Glass-Ceramics, M. S. Thesis, Alfred University, 1985. 

V. R. Stenshorn, in Effect of Hydroxyl Concentration on the Crystallization of a Lithium Silicate Glass-Ceramic, M.S. Thesis, Alfred University, 1992. 

It must be noted that the reaction mechanisms in glass/glass-ceramic powders are usually of a very complex nature. Jacquin and Tomozawa (1995) addressed the complex sintering process and the various ways of controlling it in the fabrication of lithium silicate glass-ceramics. 

Simple Silicates. The most important simple silicate glass-ceramics are based on lithium metasilicate [10102-24-6], Li SiO, lithium disilicate... 

R. Morrell and K. H. G. Ashbee, High Temperature Creep of Lithium Zinc Silicate Glass-Ceramics, Part 1, General Behavior and Creep Mechanisms, /. Mater. Sci., 8, 1253-1270 (1973). 

W. Donald, B. L. Metcalfe, D. J. Wood, J. R. Copley, The preparation and properties of some lithium zinc silicate glass-ceramic, J. Mater. Sci., 24, 3892-903(1989)... 

Fig. 8.42 Indentation crack profiles in lithium-alumin-silicate glass ceramic (heat treated 250 h at 850 °C, etched in 2.5 % HF for 5 s) indicating fracture of Li2Si203 grains accompanying crack deflection. Also note microcrack [20]. With kind permission of Elsevier... 

Dupree R., Holland D., and Mortuza M.G., "A MAS-NMR Investigation of Lithium Silicate Glasses and Glass-Ceramics,"/. Non-Cryst. Solids, 116, 148-60 (1990). 

McMillan P.W, Philips S.V., and Partridge G., "The Structure and Properties of a Lithium Zinc Silicate Glass-Ceramic,"/. Mater. Sci., 1, 269-79 (1966). 

E. Bischoff, M. Riihle, O. Sbaizero, A.G. Evans Microstructural studies of the interfacial zone of a Sic-fiber-reinforced lithium aluminium silicate glass-ceramic , J. Am. Ceram. Soc. 72, 741-745 (1989)... 

In lithium-alumo-silicate glass ceramics a higher lithium concentration due to ion exchange is reached within the surface layer than within the glass. This leads to a higher content of crystal phase in this exchanged layer during the ceramization, because lithium is incorporated into the crystal layer. 

The lithium ion exchange has hardly gained acceptance in practical applications for prestressing lithium-alumo-silicate glass ceramics. On the one hand, the compressive stresses are lower in comparison to the ion exchange with potassium below T, and on the other hand, most Li salts attack the surface so that the articles cannot be used any more. 

Adachi T., Sakka S. Microstructural changes in sol-gel derived silica gel monolith with heating as revealed by the crack formation on immersion. J. Ceram. Soc. Jpn. 1989 97 203-207 Adachi T., Sakka S. Dependence ofthe elastic moduli of porous silica gel prepared by the sol-gel method on heat treatment. J. Mater. Sci. 1990 25 4732 737 Chen A., James P.F. Amorphous phase separation and crystallization in a lithium silicate glasses prepared by the sol-gel method. J. Non-Cryst. Solids 1988 100 353-358 Chen M., Lee W.E., James P.F. Preparation and characterization of alkoxide-derived celsian glass-ceramic. J. Non-Cryst. Solids 1991 130 322-325 Chen M., James P.F., Lee W.E. Densificaation and crystallization of celsian glass derived from alkoxide gel. J. Sol-Gel Sci. Tech. 1994a 2 233-237... 

C.C. Lin et al., Composition dependent structure and elasticity of lithium silicate glasses effect of Zr02 additive and the combination of alkali silicate glasses. J. Eur. Ceram. Soc. 

The most important glass-ceramic compositions are probably based on lithium silicates. The phase diagram of the Li20-Si02 system is shown in Fig. 9.16. The commercial compositions usually contain more than about 30 percent lithia which upon crystallization yields Li2Si205 as the major phase with some Si02 and Li2Si03. 

Within the category of silicate powders there are two different varieties (1) glass and/or glass-ceramics and (2) crystalline. The first variety includes various compositions of glasses and glass-ceramics (e.g., lithium aluminosilicate and magnesium aluminosilicate), and mullite and zircon are typical examples of silicates that belong to the latter variety. 

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