Postdoctoral Fellowship: MPS-Ascend: Radiation Behavior of Complexion Containing Nanocrystalline Metals

全球不断增长的能源需求推动了对清洁能源的需求；下一代核反应堆有望通过提供稳定、高产、低排放的能源来满足这一需求。此外，预计下一代核反应堆的极端内部条件使人们对开发能够承受高温、机械应力和辐射损伤的新型金属合金产生了极大的兴趣。这项提议正在探索一类新的金属合金的行为，称为含肤色合金，由于其独特的结构，有望在高温和辐射下具有非凡的稳定性。正在利用尖端显微镜技术检查辐射引起的结构变化，并确定在下一代核反应堆的极端环境中使用含肤色合金的可行性。此外，该项目还包括社区参与的机会，如参与本科生的研究体验项目，与加州大学圣巴巴拉分校现有项目的合作，以迎合STEM中代表不足的社区的学生，以及为移民学生/研究人员传播教育资源的网站的开发。技术总结该项目探索了控制新型纳米晶肤色合金热稳定性和辐射耐受性的基本机制。靶向离子辐照研究结合高分辨率电子显微镜中的原位测试工具，正在被用来调查离子辐照引起的损伤对面色的影响，以及在辐照过程中和辐照后对材料性能的影响。拟议研究的目标是：(A)设计和创建包含肤色的纳米晶合金模型，(B)探测辐射前后随着温度和剂量的变化而发生的微观结构变化，以探索辐射缺陷对肤色行为的影响，以及(C)利用一套原位照射、加热和机械测试技术，通过实时可视化来了解潜在的机制。除了其研究努力，这项提议还通过本科生水平的指导机会，为K-12学校的教育计划，以及为移民学生/研究人员提供教育资源，扩大STEM领域中代表性不足的社区的机会，特别是关注扩大美国和巴西之间的教育和研究途径。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

NON-TECHNICAL SUMMARYGrowing energy demands worldwide have driven a need for clean energy sources; next-generation nuclear reactors promise to fulfill this need by serving as a stable, high production energy source with low emissions. Furthermore, the extreme internal conditions predicted for these next-generation nuclear reactors have led to considerable interest in the development of novel metal alloys capable of withstanding high temperatures, mechanical stresses, and radiation damage. This proposal is exploring the behavior of a new class of metal alloys, called complexion-containing alloys, that promise exceptional stability under high temperatures and radiation due to their unique structure. Cutting-edge microscopy techniques are being utilized to examine the structural changes caused by radiation and determine the feasibility of using complexion-containing alloys within the extreme environment of next-generation nuclear reactors. In addition, this project incorporates opportunities for community engagement, such as participation in Research Experiences for Undergraduates Programs, collaborations with existing programs at the University of California, Santa Barbara that cater to students from underrepresented communities in STEM, and the development of a website for disseminating education resources for immigrant student/researchers.TECHNICAL SUMMARYThis project explores the fundamental mechanisms that govern thermal stability and radiation tolerance in novel nanocrystalline complexion-containing alloys. Targeted ion irradiation studies coupled with in-situ testing tools in high-resolution transmission electron microscopes are being utilized to investigate the influence of ion irradiation induced damage on complexions and the subsequent implications for material properties exhibited during, and post-, irradiation. The objectives of the proposed research are: (a) design and create a model nanocrystalline alloy containing complexions, (b) probe microstructural changes pre- and post-irradiation as a function of temperature and dose to explore the influence of radiation defects on complexion behavior, and (c) utilize a suite of in-situ irradiation, heating, and mechanical testing techniques to develop an understanding of the underlying mechanisms through real-time visualization. In addition to its research endeavors, this proposal is expanding opportunities for underrepresented communities in STEM fields through mentoring opportunities at the undergraduate level, education programs for K-12 schools, and providing educational resources for immigrant student/researchers, with a particular focus on expanding educational and research pathways between the U.S. and Brazil.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.