f.V Crystal growth

tion nuc DSC) methods are, in principle, much faster. In this paper, we experimentally test two non-isothermal tes an glass c various silicate glasses, the measured crystal nucleation rates vary from 10 m3 s1 to 1013 m3 s1 [2]. Despite the fact that it gives correct values of nucleation rate and time-lag for nucleation, Tammann’s method is quite laborious and has limitations [2]. Beginning in 1980s, alternative methods based on DTA/DSC exper-iments have been proposed, see e.g. [3–8] to study crystallization can be detected at a lower temperature. Therefore, a plot of 1/Tc versus TN, the temperature of nucleation treatment for a given time, may reflect the temperature dependence of the nucleation rate, or more exactly, of the crystal number den-sity nucleated in a given period of time. Sometimes, the height of the crystallization peak is also used [5,6], since, to a first approximation, the peak area is considered con-stant, while its width is determined by the time for complete crystallization, which depends on the number of nuclei and on the crystal growth rate. Thus one can expect a decrease ofE-mail address