Effect of K<sub>2</sub>O/SiO<sub>2</sub> ratio on the crystallization of leucite in silicate-based glasses


  • Pat Sooksaen Faculty of Engineering and Industrial Technology, Silpakorn University and Center of Excellence for Petroleum, Petrochemicals and Advanced Materials, Chulalongkorn University
  • Janjira Boonmee Faculty of Engineering and Industrial Technology, Silpakorn University
  • Chaiyaporn Witpathomwong Faculty of Engineering and Industrial Technology, Silpakorn University
  • Somthida Likhitlert Faculty of Engineering and Industrial Technology, Silpakorn University


Leucite, Quenching, Heat treatment, Glass-ceramics, X-ray diffraction


Leucite-based glass-ceramics were prepared by controlled crystallization of suitable glass compositions to give required crystalline phase/s. Three glass batches in the system SiO2 - K2O - NaO2 - Al2O3 - TiO2 - CaO were prepared by varying K2O/SiO2 ratio, then melted and quenched. Glasses were characterized for onset of crystallization temperatures by differential thermal analysis (DTA), and heat treatments were carried out from 850 – 1000°C for 4 hours for controlled crystallization of leucite phase. Physical, chemical and crystal structure characterizations were carried out using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). XRD found leucite as a major phase in all heat treatment temperatures. Increasing the heat treatment temperature as well as increasing the amount of K2O/SiO2 ratio caused the amount of leucite phase to increase also. The silicate chain structure was found from FT-IR analysis, which confirmed the appearance of leucite phase. SEM indicated that increasing K2O/SiO2 ratio in the glass batch led to a slight increase in the crystal size, and also a slight change in the morphology of the leucite phase. Glass with the highest K2O/SiO2 ratio in this study, when heat-treated at 1000°C, showed an increased amount of secondary phase/s as opposed to the main leucite phase according to XRD data.


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Kelly, J.R. 2004. Dental ceramics: current thinking and trends. Dent. Clin. North Am. 48(2) : 513–530.

Kelly, J.R., Nishimura, I. and Campbell, S.D. 1996. Ceramics in dentistry: historical roots and current perspectives. J. Prosthet. Dent. 75(1) : 18–32.

Hench, L.L. 2005. Bioceramics: from concept to clinic. J. Am. Ceram. Soc. 74(7) : 1487–1510.

Höland, W., Rheinberger, V., Apel, E. and Hoen, C. 2007. Principles and phenomena of bioengineering with glass-ceramics for dental restoration. J. Eur. Ceram. Soc. 27(2-3) : 1521–1526.

Kelly, J. R., Campbell, S. D. and Bowen, H. K. 1989. Fracture surface analysis of dental ceramics. J. Prosthet. Dent. 62(5) : 536–541.

Mackert, J.R., Russell, C.M. and Williams, A.L. 2001. Evidence of a critical leucite particle size for microcracking in dental porcelains. J. Dent. Res. 80(6) : 1574–9.

Mackert, J.R., Butt, M.B. and Fairhurst, C.W. 1986. The effect of the leucite transformation on dental porcelain expansion. Dent. Mater. 2(1) : 32–36.

Novotna, M. and Maixner, J. 2006. X-ray powder diffraction study of leucite crystallisation. Z. Kristallogr. Suppl. 23 : 455-459.

Holand, W. and Beall, G.H. 2002. Glass-ceramic technology. Westerville, Ohio: The American Ceramic Society : 372.

Cattell, M.J., Chadwick, T.C., Knowles, J.C. and Clarke, R.L. 2005. The crystallization of an aluminosilicate glass in the K2O–Al2O3–SiO2 system. Dent. Mater. 21 : 811–822.

Cattell, M. J., Chadwick, T.C., Knowles, J.C., Clarke, R.L. and Samarawickrama D.Y.D 2006. The nucleation and crystallization of fine grained leucite glass-ceramics for dental applications. Dental. Materials. 22(10) : 925–933.

Höland, W., Frank, M. and Rheinberger, V. 1995. Surface crystallization of leucite in glass. J. Non-Cryst. Solids. 180(2-3) : 292–307.

Höland, W. 1997. Biocompatible and bioactive glass-ceramics − state of the art and new directions. J. Non-Cryst. Solids. 219(1) : 192-197.

McMillan, P. 1979. Glass-ceramics. 2nd ed. London: Academic Press Inc.

Beall, G. 1989. Design of glass-ceramics. Solid State Sci. 3 : 333–354.

James, P. 1982. Nucleation in glass forming systems—a review. In: Simmons, J.H., Uhlmann, D.R., Beall, G. (eds) Advances in ceramics, nucleation and crystallisation in glasses. Columbus, Ohio: The American Ceramic Society.

Grossman, D.G. 1985. Cast glass-ceramics. Dent. Clin. North Am. 29 : 719–723.

Sooksaen, P. and Reaney, I.M. 2008. Thermal analysis and phase evolution of ferroelectric PbTiO3 obtained from silicate and borate based glasses. J. Mater. Sci. 43(4) : 1265- 1269.

Doremus, R.H. 1994. Glass science. 2nd ed. New York: Wiley.

Shelby, J.E. 2005. Introduction to glass science and technology. 2nd ed. Cornwall: TJ International.

Grossman, D.G., and Isard, J.O. 1969. Crystal clamping in PbTiO3 glass-ceramics. J. Mater. Sci. 4 : 1059.

Sooksaen, P., Reaney, I.M. and Sinclair, D.C. 2005. Lead titanate glass-ceramics derived from a silicate-based melt. J. Mater. Res. 20(5) : 1316-1323.

Denry, I.L., Holloway, J.A. and Colijn, H.O. 2001. Phase transformations in a leucitereinforced pressable dental ceramic. J. Biomed. Mater. Res. 54(3) : 351–359.

Szabo, I., Nagy, B., Völksch, G. and Höland, W. 2000. Structure, chemical durability and microhardness of glass-ceramics containing apatite and leucite crystals. J. Non-Cryst. Solids. 272(2-3) : 191–199.

Elliott, J.C. 1994. Structure and chemistry of the apatites and other calcium orthophosphates. Amsterdam :Elsevier Science.

Kuriakose, T.A. and Kalkura, S.N. 2004. Synthesis of stoichiometric nano crystalline hydroxyapatite by ethanol-based sol–gel technique at low temperature. J. Cryst. Growth. 263(1-4) : 517–523.




How to Cite

P. Sooksaen, J. Boonmee, C. Witpathomwong, and S. Likhitlert, “Effect of K<sub>2</sub>O/SiO<sub>2</sub> ratio on the crystallization of leucite in silicate-based glasses”, J Met Mater Miner, vol. 20, no. 1, Apr. 2017.



Original Research Articles