Abstract:
To reduce the sintering temperature of lithium titanate-based microwave dielectric ceramics, this study successfully prepared
xLiVO
2-(1−
x)Li
2TiO
3 composite ceramics (with
x ranging from 0.025 to 0.20) via a solid-phase sintering method. The sintering behavior and phase composition of the composite ceramics were systematically investigated under varying LiVO
2 additions and sintering temperatures, focusing on factors influencing dielectric properties and temperature stability. The results reveal that as the LiVO
2 content increases, the temperature coefficient of resonant frequency (
τf) progressively decreases, shifting from positive to negative values. A near-zero
τf was achieved at
x=0.05. However, the LiVO
2 content critically impacts the quality factor, and excessive LiVO
2 significantly degrades the
Q×
f value (Product of quality factor and measured resonant frequency) of the
xLiVO
2-(1−
x)Li
2TiO
3 binary system. Furthermore, incorporating low-melting-point LiVO
2 substantially reduces the sintering temperature from
1200℃ (pure Li
2TiO
3) to 825—900℃. For the sample with
x=0.075 sintered at 850℃, optimal properties were attained:
Q×
f=
22505 GHz,
τf=−12.79×10
−6/℃, relative permittivity
εr=27.47. This study successfully achieved
xLiVO
2-(1−
x)Li
2TiO
3 composite microwave dielectric ceramics with a low temperature coefficient of resonant frequency while significantly reducing the sintering temperature.