Radiation Response and High Temperature Stability of Nanotwinned Metals

本研究项目的目的是阐明纳米孪晶结构在辐射和高温等极端环境下的行为。随着核电在满足我们对环境可接受的能源需求方面发挥着越来越重要的作用，能够承受极端辐射环境的结构材料的设计是未来核电系统面临的关键挑战。最近，一类被称为纳米孪晶金属的新型纳米材料显示出非凡的结构特性，如超高屈服强度、高延展性和在高温下增强的稳定性。因此，他们的优化设计可能会导致纳米孪晶金属作为下一代抗辐射材料的性能增强。采用多尺度计算方法和原子模拟，该项目将解决与纳米结构材料对点缺陷形成和相互作用引起的辐射效应的响应有关的基本问题。该项目还研究了一些关键问题，即蠕变和晶粒生长，它们成为纳米结构金属在高温下变形的主要机制。这项研究将有助于纳米结构金属科学和技术的几个重要领域，通过深入了解在极端条件下控制其行为的变形机制。它的目标是在实验、分析和制造工作之间产生协同作用，为核反应堆和存储设施、国防和生物医学应用等关键结构应用的新型纳米材料的最佳设计。此外，从事该项目的研究生和本科生将在纳米力学和计算材料科学等多学科领域打下坚实的基础。

The goal of this research project is to elucidate the behavior of nanotwinned structures under extreme environments due to irradiation and high temperatures. As nuclear power plays an increasingly vital role in meeting our demand for energy in an environmentally acceptable manner, the design of structural materials that can sustain extreme radiation environments is a critical challenge for future nuclear power systems. Recently, a new class of nanomaterials known as nanotwinned metals has shown extraordinary structural properties such as ultra-high yield strength, high ductility, and enhanced stability at high temperatures. Thus, their optimal design could lead to a possibly enhanced performance of nanotwinned metals as next-generation radiation-resistant materials. Employing multi-scale computational methods and atomistic simulations, the project will address fundamental questions pertaining to the response of nanostructured materials to radiation effects caused by formation and interaction of point defects. This project also investigates critical issues, namely, creep and grain growth, that become dominant mechanisms of deformation in nanostructured metals at elevated temperatures.The research will contribute to several important areas of nanostructured metal science and technology by providing insight into the deformation mechanisms governing their behavior under extreme conditions. It aims to lead to a synergy among experimental, analytical and manufacturing efforts for the optimal design of novel nanomaterials for critical structural applications such as nuclear reactors and storage facilities, defense and biomedical applications. Moreover, graduate and undergraduate students working on the project would develop a strong foundation in the highly multidisciplinary areas of nanomechanics and computational materials science.