Iso-conversional study of crystallization activation energy of amorphous-crystallization transformation for Se79Te20Pb1 glass using non-isothermal differential scanning calorimetry technique

Abstract

The ternary Se₇₉Te₂₀Pb₁chalcogenide glass is prepared using melt quenching technique. Differential scanning calorimetry technique (DSC) is used to investigate the kinetics of crystallization of amorphous-crystallization (a-c) phase transformation under non-isothermal conditions at three different heating rates; 5, 10 and 15&deg; C min^-1. The variation of crystallized activation energy (<em>E_c</em>) with crystallized fraction (<em>ϰ</em>) and hence, with temperature (<em>T</em>) is investigated using five iso-conversional methods namely KAS, OFW, Friedman, Tang and Chen and Starink. It is found that <em>E_c</em> is not constant but vary with <em>ϰ</em> as well as <em>T</em>. Thus, the iso-conversional analysis of investigated glass indicates that the assumption of constant <em>E_c</em> is not appropriate.