氧化物/氧化物自生复合陶瓷的生长机理与微观结构的研究进展

基于国外定向凝固氧化物／氧化物自生复合陶瓷的晶体生长动力学行为研究，阐述了其动力学机制，分析动力学因素对微观结构的影响，探讨了晶体生长动力学行为与微观结构之间的关系；同时结合以重力、超重力下燃烧合成、快速凝固技术所制备的新型高强韧Al2O3／YSZ自生复合陶瓷，探讨了自生复合陶瓷在快速凝固条件下的晶体生长动力学行为。结合定向凝固与快速凝固两种晶体生长机制，得出过冷度、凝固界面前沿的温度梯度是影响晶体生长方式的重要因素，且受二者控制的晶体生长速率则决定材料的微观结构与形态。

Study on Growth Mechanisms and Microstructures of Oxide/Oxide Self-forming Composite Ceramics

Based on studies of kinetic behaviors of crystal growth of directionally solidified oxide/oxide selfforming composite ceramics, their kinetic mechanisms are introduced, and the influences of kinetic parameters on the microstructures as well as the correlation of kinetic behaviors and morphologies of microstructures are discussed. Meanwhile, by combining with a new high-performance Al2O3/YSZ self-forming composite ceramics prepared by combustion synthesis and rapid solidification under gravity and high gravity respectively, the kinetic behaviors of crystal growth of eutectic composite ceramics are investigated. Through the mechanisms of crystal growth under the different conditions of directional solidification and rapid solidification, it is obtained that the degree of under-cooling and solidification thermal gradient are two important factors to play the predominant role in crystal growth, whereas the final microstructures of materials are dependent on the crystal growth rate controlled by the above two factors.