Effect of different Ca/La ratio on structure and properties of Al–B–Si glass with low dielectric constant

Abstract

Aluminoborosilicate glasses with different CaO/La2O3 ratios were prepared by conventional melt quenching method. The structure, thermal property and dielectric property were investigated by FTIR, DSC and impedance instrument. Respectively. The FTIR spectra indicate that the amount of silicon oxygen tetrahedron groups with different bridge oxygens first decreases and then increases slightly with the decrease of the CaO/La2O3 ratio, which results in the structure first loose and then compact. The phenomenon is due to the transformation between [BO3] and [BO4]. As the CaO/La2O3 ratio decreases, thermal stability varies and crystallization peak at the range of 1158–1192 °C increases. At the same time, an obvious crystallization peak shows at about 900 °C, indicating the tendency of increasing crystallization. With the increase of CaO, at the expense of La2O3, the dielectric constant fluctuations up and down. Better dielectric property occurs when the CaO/La2O3 ratio reaches 44.83 and 1.86. The dielectric properties of samples RM-1, RM-2 and RM-5 are better than those of E-glass fiber.