CAREER: Understanding Elevated-Temperature Grain Boundary Deformation Processes of High-Temperature Structural Alloys through Grain Boundary Engineering

本项目旨在应用晶界工程技术开发镍基高温合金、Ti2AlNb金属间化合物等高温结构合金。拟议项目的主要目标是更好地了解高温结构合金的加工步骤、晶界特征分布(GBCD)和蠕变行为之间的相互关系。这项研究的主要目标是：(1)处理具有随机和特殊晶界分布的微观组织；(2)测量晶界特征分布(GBCD)；(3)进行不同微观组织的蠕变试验；(4)模拟晶粒度、晶界滑动和晶界特征对力学行为的影响。该项目导致了一种可用于增强高温结构材料的机械性能的加工方法的开发。教育推广部分结合了项目研究部分使用的研究工具，并有助于增加材料科学与工程(MS&amp；E)专业本科生的数量。%该研究通过晶界工程发展了对结构材料变形机制的新理解，超出了目前的技术水平。研究结果对开发更好的高温材料具有一定的参考价值。***

This project aims at applying grain-boundary engineering to develop high-temperature structural alloys such as Ni-based superalloy and Ti2AlNb intermetallics. Major objective of the proposed project is to develop better understanding of the inter-relationship of processing steps, grain boundary character distribution (GBCD), and creep behavior of high-temperature structural alloys. The main goals of this study are ; (1) to process microstructures with a distribution of random and special grain boundaries; (2) to measure grain boundary character distribution (GBCD); (3) to perform creep testing of varied microstructures; (4) to model the effects of grain size, grain boundary sliding, and grain boundary character on mechanical behavior. The project leads to the development of a processing methodology useful to enhance the mechanical behavior of high-temperature structural materials. The educational outreach component incorporates the research tools used in the research portion of the project and contributes to an increase in the number of undergraduate students majoring in materials science and engineering (MS&E).%%%The research develops new understanding of the deformation mechanisms of structural materials beyond the present state of the art through grain-boundary engineering. The results are applicable for development of better materials for high-temperature applications. ***