Synthesis and characterization of nanosized pure α-cordierite glass-ceramic powders

This work reports the synthesis and characterization of 2MgO·2Al2O3·5SiO2 glass-ceramic powder produced through the Pechini method. The synthesized glass powder was pressed to form disk pellets, which were sintered at 1000, 1100, 1150, 1200, 1250, and 1300 °C. Moreover, the Raman and FTIR spectroscopies were used for better understanding of the phase transformation. Refractive index and extinction coefficient of the synthesized samples were determined by Kramers-Kronig dispersion relations using FTIR transmittance spectra. The SEM micrographs of the glass-ceramic showed a uniform distribution of the particles and growth of nanocrystallines with particle sizes between 42 and 48 nm. Besides, energy-dispersive spectroscopy proved stoichiometric composition of α-cordierite sintered at 1300 °C. The dielectric constant and the hardness of the glass-ceramic sintered at 1300 °C were measured. The value of the dielectric constant as low as 5.19 has been mainly ascribed to the high purity of the α-cordierite.