The nucleation of K2O center dot TiO2 center dot 3GeO(2) glass under non-isothermal conditions

Abstract

The nucleation of germanate K2O center dot TiO2 center dot 3GeO(2) glass under non-isothermal conditions was studied by the DTA method. The temperature ranges of nucleation and crystal growth of this glass partly overlap. The influence of the mass of the glass sample as well as, the time and temperature of the pre-DTA heat treatment on the DTA parameters T-p, (delta T)(p), and Delta T-p was investigated. A complex behavior of these parameters was evidenced. It was shown that for fixed temperatures, increasing the annealing time of the pre-DTA heat treatment resulted in a decrease in the temperature of the DTA peak (T-p). The curve of the dependence of DTA peak heights (delta T)(p) on time showed a maximum and the parameter Delta T-p continually increased with increasing time. The influence of the temperature of the pre-DTA heat treatment on the DTA parameters showed that for annealing times t>t(ind), the dependences of T-p(-1) and Delta T-p vs. T corresponded to the dependence of Ion Tin the case when the regions of I and U partly overlapped. As shown, in this case. the change of (delta T)(p) vs. T is not convenient for an analysis of the nucleation behavior of the glass.