Segregation and Convection Studies in gamma-TiA1 Alloy Solidification

9700206科斯特本提案用于评估具有重要工业意义的TiAl合金铸件。这种合金的一种工程形式，被称为y-TiAl，目前处于研究阶段，预计将在不久的将来引入航空航天工程和其他尖端应用。这种合金有两个类似于Galn的属性，它们被认为有助于加强熔体中的偏析：(1)元素密度的差异，(2)元素的不同熔化温度。来自TiAl和GaN的研究结果将有助于更好地理解热和溶质驱动的金属合金熔体中的偏析和流动的物理机制。这项研究的结果可以提供有用的实验结果，促进新的流体力学模型的开发，以及调整工业加工炉的设计。这一合作研究项目解决了自然对流槽中流体物理和化学分离研究的基本问题，结合工业上相关的垂直Bridgman结晶，包括冶金表征和拉伸测试，将提高对TiAl合金铸件制造要求的理解。该研究项目在理论和实验之间取得了平衡，将为航空航天行业和铝制造业提供有价值的发现。

9700206 Koster This proposal is for the assessment of industrially important TiAl alloy castings. One engineering form of that alloy, known as y-TiAl, currently in a research stage, is expected to be introduced in the near future to aerospace engineering and other cutting edge applications. That alloy has two attributes similar to the Galn, which are thought to contribute to the enhanced segregation in the melt: (1) the difference in density of the elements, and (2) the different melting temperatures of the elements. The research results from both TiAl and Galn will contribute to a better understanding of the physics of segregation and flow in thermally and solutally driven metallic alloy melts. The outcomes of this research could provide useful experimental results that will spur the development of new fluid mechanical models as well as adjusting designs for industrial processing furnaces. This collaborative research project addresses fundamental issues on fluid physics and chemical segregation study in the natural convection cell, combined with the industrially relevant vertical Bridgman crystallization, including metallurgical characterization and tensile testing, will improve the understanding of manufacturing requirements for TiAl alloy castings. The research project has a balance between theory and experiment, and will provide valuable findings for the aerospace industry as well as the aluminum manufacturing industry.