Crystallization Kinetics of the LiBO ₂ –Nb ₂ O ₅ Glass Using Differential Thermal Analysis

Abstract

The crystallization kinetics in the glass system (100− x )LiBO 2 − x Nb 2 O 5 (5≤ x ≤20, in molar ratio) prepared via the conventional metal‐plate quenching technique have been studied by isothermal and non‐isothermal methods using differential thermal analyses. X‐ray powder diffraction studies carried out on heat‐treated (500°C) glasses reveal the evolution of lithium niobate crystalline phase along with a minor phase of LiBO 2 . The exponent n in the Jhonson–Mehl–Avrami (JMA) equation applied to the isothermal process is 2.62, which is in excellent agreement with that obtained under the non‐isothermal process (2.67). The activation energies for crystal growth obtained from JMA equation under isothermal condition, modified Ozawa and Kissinger equations under non‐isothermal conditions, are 293, 311, and 306 kJ/mol, respectively.