【摘要】 本文研究了第二相添加剂（Ta₂O₅,ZrO₂）对β〃-Al₂O₃显微结构的影响,同时观察了它们的相组成和电性能。实验结果表明,第二相添加剂能在不同程度上改善β〃-Al₂O₃的显微结构。如果第二相促使液相在坯体中生成,如Ta₂O₅,β〃-Al₂O₃晶粒倾向于均匀生长;如果第二相在高温下不生成液相,如ZrO₂,它对基体显微结构的影响则取决于所添加的第二相的含量。适当的添加量可以导致β〃-Al₂O₃陶瓷获得较为均匀的细晶显微结构,但是,过量的第二相添加量将对β〃-Al₂O₃的电性能不利。更多还原

【Abstract】 In this study, the effect of additives of the second phase（Ta₂O₅, ZrO₂） on the microstructure of β〃-alumina ceramics, the phase composition and the electrical properties of the ceramics has been studied.The results show that both kinds of the additives can improve the microstructure of β〃-alumina ceramics to a certain extent. If the second phase accelerates the formation of the liquid phase, such as Ta₂O₅, then the crystal grains of β〃-Al₂O₃ grow uniformly; otherwise, such as ZrO₂, the effect of the additive on the microstructure of β〃-Al₂O₃ will depend upon the content of the second phase. By doping suitable amount of additive, microstructure with uniform small grain size can be obtained.Surplus amount of additive will weaken the electrical properties.更多还原