Low-temperature sintered ZnNb2O6–CaTiO3 ceramics with near-zero τf
2014; Elsevier BV; Volume: 147; Issue: 3 Linguagem: Inglês
10.1016/j.matchemphys.2014.06.013
ISSN1879-3312
AutoresMei Guo, Yuxia Li, Gang Dou, Shuping Gong,
Tópico(s)Dielectric properties of ceramics
ResumoThe phases, microstructure and microwave dielectric properties of ZnNb2O6–xCaTiO3 ceramics with BaCu(B2O5) glass additions prepared by solid state reaction method were charactered by using X-ray diffraction, Scanning electron microscopy and Advantest network analyzer. The τf of ZnNb2O6 was modified to near 0 ppm °C−1 by incorporating CaTiO3 with opposite τf values on the basis of Lichtenecker empirical rule. The microwave dielectric properties of ZnNb2O6–xCaTiO3 (x = 8.0 wt.%) samples with BaCu(B2O5) glass additives sintered in 900–1000 °C were investigated, and the results indicated that the behaviors of the εr and Q × f were associated with the sintering temperature and the amount of BaCu(B2O5) glass. The sintering temperature of the ceramics was reduced to 950 °C from 1175 °C. Addition of 5.0 wt.% BaCu(B2O5) glass in ZnNb2O6–xCaTiO3 (x = 8.0 wt.%) ceramics sintered at 950 °C showed excellent dielectric properties of εr = 20.2, Q × f = 14,100 GHz (f = 7.3 GHz) and τf = 0 ppm °C−1. Moreover, the material had a chemical compatibility with silver, which represented a promising candidate materials for low-temperature-co-fired ceramics applications.
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