Phase Transformation Kinetics in Ceramics: Role of Aliovalent Dopants

拟议研究的目的是检查 异价掺杂对相变动力学的影响 陶瓷和确定基本的运输机制。工作是 提出了Bi_2 O_3、CaTiO_3-YCrO_3和PbI_2-CdBr_2体系。Foe相 在这些系统中的分离发生扩散在一个或多个 子格是必要的。掺杂和未掺杂的样品将 制造，退火，并通过透射电子和 光学显微镜和X射线衍射。缺陷的作用 化学和异价掺杂剂的影响将被明确 包括在相变的理论分析中， 动力学拟议的研究将影响确定 陶瓷相平衡与工艺发展 重要的陶瓷材料。

The objective of the proposed research is to examine the effect of aliovalent dopants on the kinetics of phase transformation in ceramics and identify fundamental transport mechanisms. Work is proposed on Bi2O3, CaTiO3-YCrO3, and PbI2-CdBr2 systems. Foe phase separation in these systems to take place diffusion on one or more sub-lattices is necessary. Doped and undoped samples will be fabricated, annealed, and examined by transmission electron and optical microscopy, and X-ray diffraction. The role of defect chemistry and the effects of aliovalent dopants will be explicitly included in the theoretical analysis of phase transformation kinetics. The proposed research will impact on the determination of phase equilibria in ceramics and the development of technologically important ceramic materials.