Effect of B2O3 on the aqueous tape casting and microwaveproperties of Li2O–Nb2O5–TiO2 ceramics

The effect of B2O3 addition on the aqueous tape casting, sintering, microstructure and microwave dielectric properties of Li2O-Nb2O5-TiO2 ceramics has been investigated. The tape casting slurries exhibit a typical shear-thinning behavior without thixotropy, but the addition of B2O3 increases the viscosity of the slurries significantly. It was found that doping of B2O3 can decrease the tensile strength, strain to failure and density of the green tapes. The sintering temperature could be lowed down to 900℃ with the addition of 2 wt% B2O3 due to the liquid phase effect. No secondary phase is observed. The addition of B2O3 does not induce much degradation on the microwave dielectric properties. Optimum microwave dielectric properties of εr 67, Q×f 6560 GHz are obtained for Li2O-Nb2O5-TiO2 ceramics containing 2 wt% B2O3 sintered at 900 1C. It represents that the ceramics could be promising for multilayer low-temperature co-fired ceramics (LTCC) application.

Effect of B2O3 on the aqueous tape casting and microwave properties of Li2O-Nb2O5-TiO2 ceramics

The effect of B₂O₃ addition on the aqueous tape casting, sintering, microstructure and microwave dielectric properties of Li₂O–Nb₂O₅–TiO₂ ceramics has been investigated. The tape casting slurries exhibit a typical shear-thinning behavior without thixotropy, but the addition of B₂O₃ increases the viscosity of the slurries significantly. It was found that doping of B₂O₃ can decrease the tensile strength, strain to failure and density of the green tapes. The sintering temperature could be lowed down to 900 °C with the addition of 2 wt% B₂O₃ due to the liquid phase effect. No secondary phase is observed. The addition of B₂O₃ does not induce much degradation on the microwave dielectric properties. Optimum microwave dielectric properties of ε_r=67, Q×f=6560 GHz are obtained for Li₂O–Nb₂O₅–TiO₂ ceramics containing 2 wt% B₂O₃ sintered at 900 °C. It represents that the ceramics could be promising for multilayer low-temperature co-fired ceramics (LTCC) application.