Fatigue Crack Propagation in Ceria-Partially-Stabilized Zirconia-Alumina Composites

本研究旨在研究氧化锆陶瓷的工艺、微观结构和循环疲劳行为之间的关系。具体地说，研究的目的首先是了解这些相变增韧材料的循环疲劳机制，其次是通过加工相关组织的变化来控制这一机制。在研究中将使用一些内部加工的CeO_2部分稳定的氧化锆/氧化铝复合材料来研究裂纹屏蔽的作用以及成分、微观结构和环境对循环疲劳裂纹扩展的影响。还将对相变区屏蔽和裂纹桥联等增韧机制进行理论计算。预计这一结果将对我们理解多晶陶瓷材料的循环疲劳产生重大影响。

The proposed research is a study of the relationship between processing, microstructure, and cyclic fatigue behavior in zirconia ceramics. Specifically, the objective of the research is first, to understand the mechanism of cyclic fatigue in these transformation toughened materials, and second, to control this mechanism through processing related changes in the microstructure. A number of in- house processed ceria partially stabilized zirconia/alumina composites will be used in the study to investigate the role of crack shielding and the effects of composition, microstructure, and environment on cyclic fatigue crack propagation. Theoretical calculations on toughening by such mechanisms as transformation zone shielding and crack bridging will also be conducted. It is expected that the results will have a significant impact on our understanding of cyclic fatigue in polycrystalline ceramic materials.