Microstructure and Mechanical Behavior of FeNiMnAl Eutectic Alloys

该奖项由2009年美国复苏和再投资法案(公法111-5)资助。技术总结本建议的目的是利用最先进的技术，了解和模拟在最近发现的高强度、延展性、两相FeNiMnAl共晶合金Fe30Ni20Mn35Al15中，不同片层间距的微结构和变形机制，作为温度和应变率的函数来控制强度和塑性。在达特茅斯学院，工作重点将是微结构表征、力学测试、确定变形机制和建模。通过橡树岭国家实验室的合作，将使用LEAP进行微量化学测量，并使用日立3300HRTEM对界面进行微观结构表征。虽然这项工作主要集中在一种特定的共晶合金上，但预计所产生的基于实验观察的模拟将适用于共晶合金作为一个整体，为提高多晶层片状组织的强度和塑性提供一个变革性的范例。非技术总结本项目的目的是了解控制新发现的高强度、延展性、FeNiMnAl合金的强度和塑性的变形机制，这种材料可能被用于高温发电厂应用。这项工作将使用达特茅斯学院和橡树岭国家实验室的各种先进材料表征技术。该项目还将评估现有的类似材料的强度和延展性模型，并根据实验观察的变形机制开发新的模型，以期为如何提高FeNiMnAl合金和具有类似微观结构的合金的强度和延展性开发一种范例。研究结果将发表在被引用的期刊上，在会议上展示，并在网页上记录下来。该项目将培养一名博士生和几名本科生。2008年春，达特茅斯大学塞耶工程学院推出了一个博士学位。“创新计划”旨在向学生传授在创新过程中取得成效所需的技能。创新奖学金基金可用于支持博士生第三年后的研究。本科生将与博士生的学习密切结合，将得到达特茅斯国家荣誉女性科学项目或达特茅斯总统奖学金的支持。此外，美国国防部/国家科学基金会资助的一名暑期学生将每年参与该项目。

This Award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).TECHNICAL SUMMARYThe objective of this proposal is to understand and model the microstructure and deformation mechanisms controlling the strength and ductility as a function of temperature and strain rate for different lamellar spacings in a recently-discovered, high-strength, ductile, two-phase, FeNiMnAl eutectic alloy, Fe30Ni20Mn35Al15, using state-of-the-art techniques. At Dartmouth College, work will focus on microstructural characterization, mechanical testing, determining deformation mechanisms and modeling. Microchemical measurements using a LEAP and microstructural characterization of interfaces using a Hitachi 3300 HRTEM will be performed through collaborations at the Oak Ridge National Laboratory. While the work is focused on a particular eutectic alloy, it is expected that the resulting experimental observation-based modeling will have applicability to eutectic alloys as a whole providing a transformative paradigm for improving the strength and ductility of polycrystalline lamellar microstructures.NON-TECHNICAL SUMMARYThe aim of this project is to understand the deformation mechanisms controlling the strength and ductility of a recently-discovered, high-strength, ductile, FeNiMnAl alloy, a material that could potentially be used in high-temperature power plant applications. The work will use a variety of advanced materials characterization techniques both at Dartmouth College and at the Oak Ridge National Laboratory. The project will also evaluate existing models of strength and ductility of similar materials and develop new models based on the experimentally-observed deformation mechanisms with a view to developing a paradigm for how to improve the strength and ductility of both FeNiMnAl alloys and alloys with similar microstructures. The results of the research will be published in refereed journals, presented at conferences, and documented on a web page. The project will lead to the training of both a Ph.D. student and several undergraduates. In spring 2008, Dartmouth's Thayer School of Engineering launched a Ph.D. "Innovation Program" designed to teach students the skills needed to be effective in the innovation process. Innovation fellowship funding is available to support the student's research after the 3rd year of their Ph.D. The undergraduates, who will integrate closely with the Ph.D. student's studies, will be supported by Dartmouth's nationally-honoured Women In Science Project or Dartmouth Presidential Scholarships. In addition, a DOD/NSF-funded summer student will work on the project each year.