Low-temperature sintering and microwave dielectric properties of BaO–0.15ZnO–4TiO2 ceramics with Li2O–B2O3–SiO2 addition

Abstract

Li 2 O-B 2 O 3 -SiO 2 (LBS) synthesized via a solid-state reaction process was chosen as a novel sintering aid for BaO-0.15ZnO-4TiO 2 (BZT) ceramics and compared with LBS glass. The influence of LBS on the sintering behaviors, phase evolution, microstructure and microwave dielectric properties of the resulting BZT ceramics have been investigated in detail. The addition of LBS significantly lowers the sintering temperature of the BZT ceramics from 1150 to 900°C without damaging its microwave dielectric properties. Small amount of LBS promote the densification of BZT ceramic and improve the dielectric properties. However, excessive LBS additions lead to growth of abnormal grain, deteriorating the dielectric properties of the BZT ceramic. The BZT ceramics doped with 8 wt% LBS addition could be well sintered at 900°C for 0.5 h and show excellent microwave dielectric properties of: e r = 27.72, Q 9 f = 20,381 GHz, s f = 5.18 ppm/°C.

Sintering Behavior and Microwave Dielectric Properties of Li₂O-B₂O₃-SiO₂ Doped 0.67CaTiO₃-0.33LaAlO₃ Ceramics

“…Similarly, Yang et al [6] studied the densification, structure, and microwave dielectric properties of Li 2 O-B 2 O 3 -SiO 2 doped MgTiO 3 -CaTiO 3 ceramics, and the ceramics exhibited better dielectric properties of ε r = 18.2, Q×f= 67000 GHz(7.9GHz), and τ f = -5.2 ppm/°C when sintered at 1025°C for 4h, indicating that LBS is an effective ternary firing agent when employed in95MCT system. However, the introduction of LBS inevitably led to the decrease of Q×f, as reported by Duan et al [7]. In their study, a secondary phase formed after the introduction of LBS, and the difference between LBS glass and LBS mixed oxides was investigated.…”

Investigation of Low‐Temperature Sintering Mechanism on BaONd2O3TiO2 Dielectric Ceramics with Li2OB2O3‐SiO2 and BaOZnOB2O3 Glasses

“…According to liquid phase sintering theory, we provides the sintering stages of BNT ceramics, and Figure presents the schematic illustration of different sintering process. At the initial stage of sintering process, the liquid phase created by LBS and BZB promotes the rearrangement of BNT particles by capillary attraction, and a relatively dense structure is obtained. Then the mass transfer is accelerated, and the grains grow up slowly during the solution‐precipitation stage.…”