Microstructure and microwave dielectric properties of lead borosilicate glass ceramics with Al2O3 |
| |
Authors: | Peng-fei Wei Hong-qing Zhou Jie Wang Yi-yuan Zhang and Feng Zeng |
| |
Affiliation: | (1) Department of Materials and Engineering, Zhejiang University, Hangzhou, 310027, China; |
| |
Abstract: | The effects of Al2O3 addition on both the sintering behavior and microwave dielectric properties of PbO-B2O3-SiO2 glass ceramics were investigated by Fourier transform infrared spectroscope (FTIR), differential thermal analysis (DTA),
X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that with the increase of Al2O3 content the bands assigned to SiO4] nearly disappear. Aluminum replaces silicon in the glass network, which is helpful for the formation of boron-oxygen rings.
The increase of the transition temperature T
g and softening temperature T
f of PbO-B2O3-SiO2 glass ceramics leads to the increase of liquid phase precipitation temperature and promotes the structure stability in the
glasses, and consequently contributes to the decreasing trend of crystallization. Densification and dielectric constants increase
with the increase of Al2O3 content, but the dielectric loss is worsened. By contrast, the 3% (mass fraction) Al2O3-doped glass ceramics sintered at 725 °C have better properties of density ρ=2.72 g/cm3, dielectric constant ɛ
r
=6.78, dielectric loss tan δ=2.6×10−3 (measured at 9.8 GHz), which suggest that the glass ceramics can be applied in multilayer microwave devices requiring low
sintering temperatures. |
| |
Keywords: | PbO-B203-SiO2 glass ceramics Al2O3 Fourier transform infrared spectroscope microstructure dielectric properties |
本文献已被 维普 SpringerLink 等数据库收录! |
|