Al2O3-Y2O3-ZrO2三相复合陶瓷的介电谱研究

采用传统的固相反应法,在1400–1500 ℃下烧结,制备得到Al₂O₃-Y₂O₃-ZrO₂三相复合陶瓷.样品的结构、形貌和电性能分别用X射线衍射(XRD)、扫描电子显微镜(SEM)及介电谱表征.XRD表明此三相复合体系无其他杂相,加入Y₂O₃及ZrO₂后使得Al₂O₃成瓷温度降低;SEM表明此体系晶粒直径为200–500 nm,并且样品随烧结温度的升高而变得更加致密,晶界更加清晰;介电损耗谱中出现峰值弛豫现象,根据Cole-Cole复阻抗谱得出其为非德拜弛豫. 关键词： 2O₃-Y₂O₃-ZrO₂三相陶瓷')" href="#">Al₂O₃-Y₂O₃-ZrO₂三相陶瓷 介电弛豫 阻抗谱 热导率

Dielectric spectroscopy of Al2 O3-Y2 O3-ZrO2 ternary composite ceramics

Al₂O₃-Y₂O₃-ZrO₂ ternary composite ceramics are synthesized via the traditional solid state reaction method and sintered at 1400-1500 ℃. The phase structure, the microstructure and the electrical properties of these samples are characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and dielectric spectra. There are not any other impurity phases in this ternary system supported by XRD patterns, and additions of Y₂O₃ and ZrO₂ into Al₂O₃ make contributions to the lower calcining heat. SEM indicates that the grain sizes of these samples are about 200-500 nm. Furthermore, the densities are improved and the grain boundaries are clearer for the samples sintered at higher temperatures. Relaxation peaks are observed in the dielectric loss plots and the relaxation is of non-Debye type according to Cole-Cole complex impedance spectrum.