IRES: US-Australia Collaboration on New High Strength, High Ductility Classes of High Entropy Alloys through Intermetallic Manipulation

提案摘要1559403 PI: Lori bassman提案标题：IRES：美国-澳大利亚合作通过金属间操纵研究新型高强度，高延展性高熵合金机构：Harvey Mudd college用于工程应用的传统合金主要由一种或两种元素组成，其他元素添加相对少量以增强材料性能。然而，含有大量额外元素通常会导致合金变脆。最近的工作，包括美国本科生与澳大利亚新南威尔士大学（UNSW）的研究人员和哈维马德学院（HMC）的Lori Bassman教授合作，已经使用新策略开发了新型金属合金。这些先进的合金，被称为高熵合金（HEAs），精心挑选了几种元素大约等量的成分，并表现出优异的材料性能。该项目将极大地扩展可用于创建成功高等教育机构的要素组合的范围。随着新战略的提出，制造强度、延展性和成本都得到改善的合金的希望将会增加。在2017年至2019年夏季的十周时间里，12名本科生将在新南威尔士大学进行实验和计算研究。主要合作者，新南威尔士大学材料科学与工程学院的Kevin Laws博士和Michael Ferry教授，以及新南威尔士大学电子显微镜部门的研究人员与HMC本科生合作多年。他们将继续为学生提供HMC无法提供的特定学科的专业知识和指导，以及广泛的物理冶金实验室，显微镜设备和培训。迄今为止，HEA领域的进展主要集中在鉴定可以形成一个或两个简单的固溶体相的特定元素体系，这些固溶相具有高热稳定性，没有脆性金属间相。在这个项目中，新的HEAs将通过增加在其他系统中出现的金属间相的延展性来开发。通过这种合金的开发，学生和他们的新南威尔士大学的导师将完善控制HEA形成和原子有序的基本原理，并探索与HEAs相比，传统合金的强度和延展性大大提高相关的变形机制。HMC本科生要完成的具体实验项目包括合金设计、合金制造、力学表征和微观组织表征。计算项目将涉及合金结构和性能的第一性原理建模。这些经验将有助于学生成熟，成为自信，热情的研究人员，为国际研究环境中的科学和工程事业做好准备。参与的学生中至少有一半是女性，少数族裔学生将被专门招募。本研究由美国国家科学基金会国际科学与工程办公室的IRES项目资助。

Abstract for proposal 1559403 PI: Lori BassmanProposal Title: IRES: US-Australia collaboration on new high strength, high ductility classes of high entropy alloys through intermetallic manipulationInstitution: Harvey Mudd CollegeTraditional alloys used in engineering applications consist primarily of one or two elements, with other elements added in relatively small quantities to enhance material properties. However, the inclusion of large quantities of additional elements typically causes alloys to become brittle. Recent work, including that by American undergraduate students working with researchers at the University of New South Wales (UNSW) in Australia and Prof. Lori Bassman of Harvey Mudd College (HMC), has led to the development of novel metal alloys using a new strategy. These advanced alloys, called high entropy alloys (HEAs), have carefully selected compositions with approximately equal amounts of several elements and have demonstrated excellent material properties. This project will greatly expand the range of combinations of elements that can be used to create successful HEAs. With the proposed new strategy will come increased promise for creating alloys with improved combinations of strength, ductility and cost. During ten week periods in the summers of 2017 to 2019, twelve undergraduate students will conduct experimental and computational research at UNSW towards this goal. The lead collaborators, Dr. Kevin Laws and Prof. Michael Ferry in the UNSW School of Materials Science and Engineering, and researchers in the UNSW Electron Microscope Unit have worked with HMC undergraduates for many years. They will continue to provide students with discipline-specific expertise and mentoring unavailable at HMC as well as extensive access to physical metallurgy laboratories, microscope facilities and training.Progress in the HEA field so far has focused on identification of specific systems of elements that can form one or two simple solid solution phases with high thermal stability and no brittle intermetallic phases. In this project new HEAs will be developed by increasing the ductility of intermetallic phases that occur in other systems. Through this alloy development, the students and their UNSW mentors will refine the fundamental principles that govern HEA formation and atomic ordering and explore the deformation mechanisms associated with greatly enhanced strength and ductility in HEAs over conventional alloys. The specific experimental projects to be performed by HMC undergraduates include alloy design, alloy fabrication, mechanical characterization and microstructural characterization. Computational projects will involve first-principles modeling of alloy structures and properties. These experiences will contribute to the maturation of the students into confident, enthusiastic researchers who are prepared for science and engineering careers in international research environments. At least half of the participating students will be female, and underrepresented minority students will be specifically recruited. This research is funded by the IRES program of the NSF Office of International Science and Engineering.