The Enhanced Phase-Forming Capacity of (1–x)Mg_0.95Co_0.05TiO₃-xCa_0.6La_0.8/3TiO₃ Dielectric Ceramics Modified Using Multiple Sintering Aids

Abstract

In this study, the phase-forming capacity of 0.9Mg0.95Co0.05TiO3-0.1Ca0.6La0.8/3TiO3 dielectric ceramics was improved by mixing multiple sintering aids (ZnO-B2O3) owing to their lower melting point. The mixed-phase systems of Ca0.6La0.8/3TiO3-modified Mg0.95Co0.05TiO3 dielectric ceramics were verified using XRD diffraction to ensure that the crystallites of different phases were present. The microstructures of the Ca0.6La0.8/3TiO3-modified Mg0.95Co0.05TiO3 dielectric ceramics were observed via SEM and EDS to investigate the relation between element ratios and grains. It was found that the phase-forming capacity of Ca0.6La0.8/3TiO3-modified Mg0.95Co0.05TiO3 was effectively enhanced, compared with the treatment that did not involve mixing multiple sintering aids (ZnO-B2O3). Additionally, the microwave dielectric performances of Ca0.6La0.8/3TiO3-modified Mg0.95Co0.05TiO3 dielectric ceramics with multiple sintering aids (ZnO-B2O3) strongly depended on the density and morphology of the specimens. When the compositions of 0.9Mg0.95Co0.05TiO3-0.1Ca0.6La0.8/3TiO3 with 1 wt% multiple sintering aids (ZnO-B2O3) showed an εr value of 22.6, a Qf value of 49,000 GHz, and a τf value of −12.8 ppm/°C, the sintering temperature was reduced from 1350 °C to 1150 °C (about 200 °C). When adding a larger amount of multiple sintering aids (ZnO-B2O3), the sintering temperature could be reduced by more than 200 °C. This study may promote the use of Ca0.6La0.8/3TiO3-modified Mg0.95Co0.05TiO3 dielectric ceramics.

Keywords

• phase-forming capacity
• multiple sintering aids
• microwave