Collaborative Research: Determination of Ni-Fe-Cr Species Dependent Transport Through Control of Temperature, Irradiation, and Grain Size

合作研究：通过控制温度、辐照度和晶粒尺寸来测定 Ni-Fe-Cr 物种依赖性传输

• 批准号: 1105681
• 负责人: Mitra Taheri
• 金额: $ 21.6万
• 依托单位: Drexel University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1105681&HistoricalAwards=false
• 关键词: Collaborative; Research; Determination; Ni; Fe

TECHNICAL SUMMARY: Ni-Fe-Cr based fcc alloys (e.g., Ni-based and austenitic steel alloys) are frequently used as structural materials in a wide range of technologies, including nuclear reactors. Many aspects of Ni-Fe-Cr alloy microstructural evolution, particularly under irradiation, are controlled by point defect transport with species dependencies that are still poorly understood. In this project a novel approach to determine the species-dependent diffusion coefficients in Ni-Fe-Cr steel alloys is proposed. It is based on measurements and modeling of Radiation Induced Segregation (RIS) of nanocrystalline materials. The proposed work integrates multiple approaches to understanding point defect transport in Ni-Fe-Cr and to RIS, including grain size control, RIS characterization tools (STEM-EDS, Focused Ion Beam, TEM, and Atom Probe tomography), and multiscale ab initio based models (including cluster expansion, kinetic Monte Carlo and rate theory modeling). The work will provide a new level of insight into the magnitude and mechanisms of Ni-Fe-Cr species-dependent transport and inform future microstructural modeling.NON-TECHNICAL SUMMARY: Ni-Fe-Cr based steels are frequently used as structural materials in a wide range of technologies, including nuclear reactors. Essential aspects of the long-term reliability of these steels, particularly under irradiation, are controlled by aspects of Ni, Fe, and Cr diffusion that are still poorly understood. The PIs propose to integrate tools from materials nanotechnology and molecular-scale computer simulation to provide new levels of insight into how Ni, Fe, and Cr are transported in these steels under extreme conditions. The results will be integrated into higher levels models that aid in the prediction of steel reliability and the development of new materials. This project will train graduate students and postdoctoral researchers to work on a multi-location team and in fundamental areas of materials characterization, modeling, and their interaction. This work will also further the involvement by some of the investigators in the Women in Nuclear Science (WINS) organization and activities at the Advanced Test Reactor National Scientific User Facility (NSUF).

Ni-Fe-Cr基fcc合金（例如，镍基和奥氏体钢合金）经常用作各种技术（包括核反应堆）中的结构材料。Ni-Fe-Cr合金微观结构演变的许多方面，特别是在辐照下，是由点缺陷传输与物种的依赖性，仍然知之甚少。在这个项目中，提出了一种新的方法来确定物种依赖的扩散系数在Ni-Fe-Cr钢合金。它是基于纳米晶材料的辐射诱导偏析（RIS）的测量和建模。拟议的工作集成了多种方法来理解Ni-Fe-Cr和RIS中的点缺陷传输，包括晶粒尺寸控制，RIS表征工具（STEM-EDS，聚焦离子束，TEM和原子探针断层扫描），以及基于多尺度从头算的模型（包括簇扩展，动力学Monte Carlo和速率理论建模）。这项工作将提供一个新的水平的洞察力的大小和机制的Ni-Fe-Cr物种依赖的运输和通知未来的微观结构modeling.NON-TECHNICAL摘要：Ni-Fe-Cr基钢经常被用作结构材料在广泛的技术，包括核反应堆。这些钢的长期可靠性的基本方面，特别是在辐照下，由Ni，Fe和Cr扩散方面控制，这些方面仍然知之甚少。 PI建议将材料纳米技术和分子尺度计算机模拟的工具整合在一起，以提供对镍，铁和铬在极端条件下如何在这些钢中运输的新见解。结果将被集成到更高级别的模型中，以帮助预测钢材的可靠性和新材料的开发。 该项目将培养研究生和博士后研究人员在多地点团队中工作，并在材料表征，建模及其相互作用的基本领域。这项工作还将促进一些调查人员参与核科学妇女组织和国家先进试验反应堆科学用户设施的活动。