Correlation between maximum crystal growth rate and glass transition temperature of silicate glasses

• Published in: Journal of non-crystalline solids Vol. 351; no. 10; pp. 789 - 794
• Main Authors: Fokin, Vladimir M., Nascimento, Marcio L.F., Zanotto, Edgar D.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.04.2005; Elsevier
• Subjects: Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Equations of state, phase equilibria, and phase transitions; Exact sciences and technology; Glass transitions; Growth from solid phases (including multiphase diffusion and recrystallization); Materials science; Methods of crystal growth; physics of crystal growth; Physics; Specific phase transitions; S170; C290; G200; N240; Crystal growth; Glass transition; Growth rate; Cooling rate; Glass; Crowth model; Silicates; Screw dislocations; Homogeneous nucleation; Glass formation
• ISSN: 0022-3093; 1873-4812
• DOI: 10.1016/j.jnoncrysol.2005.02.005

Recent publications demonstrate that the maximum homogeneous nucleation rates, I max, of silicate glasses strongly diminish with the reduced glass transition temperature, T gr (= T g/ T m/L, where T g is the glass transition temperature and T m/L is the melting point or liquidus temperature). In addition, the critical cooling rates for metallic glass formation, R c, also drop with rising T gr. From these empirical observations as well as from theoretical considerations, it is expected that the maximum crystal growth rates, U max, also depend on T gr. In this paper we test and confirm this assumption by plotting experimental U max vs. T gr for 20 silicate glasses, and then use the most common crystal growth model – screw dislocation growth – to calculate and compare maximum experimental growth rates with theoretical predictions. Despite several assumptions made for the calculations, there is good agreement between theory and experiment, both in the magnitude of U max( T gr) and in the temperature of the maximum crystal growth rate, T max U . These findings indicate that the screw dislocation growth model is a good approximation to describe crystal growth in silicate glasses.