铁电陶瓷/铁氧体复合材料的相结构与介电性能

研究了铁电陶瓷/铁氧体混合烧结体的相结构与介电性能。在900℃制备出铁电陶瓷/铁氧体复合材料,该复合材料是介电材料相与铁氧体材料相共存的复相陶瓷。铁电陶瓷/铁氧体复合材料的介电性能在低温区域主要是介电材料相起作用,而铁氧体材料主要在高温部分对复合材料的介电性能起作用。采用两相混合分布的介电常数计算公式拟合了复相陶瓷的介温曲线,并提出修正指数因子α和β,建立修正方程。

PHASE STRUCTURE AND DIELECTRIC PROPERTIES OF FERROELECTRICS AND FERRITE MIXED COMPOSITES

The composite material was prepared by mixing Pb (Ni1/3Nb2/3) O3-PbTiO3-based ferroelectrics and NiCuZn ferrite material. The phase structure and dielectric properties of the composite were investigated. The dielectric constant of composite material simulated by amending the logarithm equation and the amending coefficient were estimated. The results show that there are no other phases in the composite except dielectric phases and ferrite phase, indicating the two materials chosen in the present study are chemically compatible. It is found that there is no conventional dielectric peak appearing in the plot of dielectric constant versus temperature. The ferroelectric phase plays a main role in the dielectric constant at low temperature range from -80℃ to 20℃. The dielectric constant and the dissipation factor of composite material continuously increase with increasing temperature, which should be attributed to the leakance induced by the ferrite phase. The dielectric constant of composite material simulated was in agreement with experimental results.