Liquid Phase Processing and Synthesis at Very High Temperatures

陶瓷、玻璃、半导体和氧化物超导体的液相处理提供了一条生产这些材料的有用形式的途径，这些材料通常会因与容器的反应而受阻。本研究为这些材料探索了一种新的无容器加工方法。容器表面的非均相成核将被消除，从而能够合成非晶态材料，并改善对单晶生长的控制。无容器处理方法利用相对较大的气动力和较小的声学定位力来实现辐射加热液体的稳定悬浮。低密度液体(如水)的稳定声悬浮，以及稠密固体的空气动力悬浮，都是发展得很好的方法。在空气动力悬浮本身并不稳定的条件下，初步实验也证明了所提出的混合技术在致密固体材料上的应用。拟议的第一阶段研究旨在保持熔化过程中的悬浮稳定性，演示使用选定的陶瓷材料(例如，氧化铝、氧化物超导体、氟化物玻璃)的操作，并确定第二阶段工艺和材料性能研究的设计和操作程序。

Liquid phase processing of ceramics, glass, semiconductors, and oxide superconductors provides a route to producing useful forms of these materials which is often blocked by reaction with containers. This research explores a novel containerless processing method for these materials. Heterogeneous nucleation at container surfaces would be eliminated to enable synthesis of amorphous materials and improve control of single crystal growth. The containerless processing method uses relatively large aerodynamic forces and smaller acoustic positioning forces to achieve stable levitation of radiantly heated liquids. Stable acoustic levitation of low density liquids such as water, as well as aerodynamic levitation of dense solids, are well developed methods. Application of the proposed hybrid technique to dense solid materials has also been demonstrated in preliminary experiments under conditions for which aerodynamic levitation is not, by itself, stable. The proposed Phase I research develops to maintain levitation stability during melting, demonstrates operation with selected ceramic materials (e.g., aluminum oxide, oxide superconductors, fluoride glasses), and determines the designs and operating procedures for Phase II processing and materials property research.***//