Novel cordierite nanopowders of new crystallization aspects and its cordierite-based glass ceramics of improved mechanical and electrical properties for optimal use in multidisciplinary scopes

Nanocrystalline a-cordierite Mg2Al4Si5O18 powders have been synthesized via a novel and facile co-precipitation method using MgCl2 center dot 6H(2)O, NaAlO2, Na2SiO3 center dot 5H(2)O as starting materials. XRD, SEM, HR-TEM and EDS techniques were employed to investigate the phase structure and crystal morphology of the synthesized powders at various annealing temperatures. The kinetics of cordierite crystallization was studied under non-isothermal conditions using Differential Thermal Analysis (DTA). The apparent activation energy (E-a) of mu-cordierite crystallization, calculated by modified Kissinger model was equal 286.1 K J mol(-1) and comparable with the literature. The dielectric measurements revealed that the cordierite ceramic samples sintered at 1300 and 1350 degrees C could be successfully applied for electronic packaging under the microwave and radiowave frequency regions, respectively. (C) 2015 Elsevier B.V. All rights reserved.