Investigation of phase transformation mechanism in glass ceramic materials by using Johnson - Mehl - Avrami - Kolmogorov Parameters

In this study, phase transformation parameters were determined for %33CuO- %67PbO glass composition by using Johnson-Mehl-Avrami-Kolmogorov (JMAK) ki netics. DSC measurements were performed for different heating rates. For %33CuO- %67PbO glass composition, optical microscope photographs and x-ray diffraction stud ies were performed. Kinetic paratemers were determined for different heat treatment applied samples by using non-isothermal JMAK method. Activation energies were ob tained for exothermic peaks in the range of 201-349 kJ/mol and for endo thermic peaks in the range of 839-1430 kJ/mol. Avrami exponents were calculated in the range of 0.4 and 3.1. The y radiation effects were investigated on the reaction kinetics. Keywords: JMAK Kinetics, Reaction Kinetics, Glass-Ceramics, CuO-PbO Glass.