KDI: Multiscale Modeling of Defects in Solids

固体的变形和失效--例如在各种工程应用中使用的金属和金属合金--涉及复杂缺陷结构在长度等级上的形成和演化。例如，当飞机机翼在飞行过程中受到湍流的冲击时，金属的内部结构会发生复杂的变化，在没有检查和维护的情况下，可能会导致其故障。金属中的原子如何形成缺陷线(称为位错)，位错如何形成更大的纠缠和阵列，纠缠如何形成小间隙或空洞，纠缠和空洞如何导致微观裂缝的形成，以及这些裂缝如何长大以折断机翼：这些都是NSF KDI倡议下拟议的研究主题。多学科研究团队将利用不断增长的计算能力来明确地对每个尺度上的缺陷动态进行建模。该团队将利用新的软件技术将超级计算机模拟与可视化实用程序和一套分析工具联系起来。这些工具的组合将形成数字材料：一个虚拟实验室，探索和开发新的、优雅的缺陷动力学理论和模型，结合许多学科的见解，并在广泛的长度范围内测试和验证这些模型。该团队将利用新兴的基于互联网的协作和控制工具，不仅加快其内部多学科协作研究，还将通过开发和共享开放的、通用的软件组件来帮助领导和参与全球协作努力。%更好地理解和模拟材料的能力将推动下个世纪在重工业、交通、先进材料设计和微电子等领域的经济和技术进步。尤其是材料的变形、劣化和最终失效的方式是一个几十年前的问题，也是本研究项目的重点。在NSF KDI倡议的支持下，研究人员将使用强大的计算机、新的理论思想和方法、万维网和其他新兴技术来改变材料建模的方式。结合新的工具将使调查人员能够开发出基本的新见解，这些见解在智力上令人兴奋，在技术上也很重要。

9873214SethnaThe deformation and failure of solids - such as metals and metallic alloys used in a wide variety of engineering applications - involve the formation and evolution of complex defect structures on a hierarchy of length scales. For example, as an airplane wing is buffeted by turbulence during flight, complicated changes happen to the internal structure of the metal which can lead - in the absence of inspection and maintenance - to its failure. How the atoms in the metal form defect lines (called dislocations), how the dislocations form into larger tangles and arrays, how the tangles form small gaps or voids, how the tangles and voids lead to the formation of microscopic cracks, and how these grow to break the wing: These form the topic of the proposed research under the NSF KDI initiative. The multidisciplinary research team will exploit ever-increasing computing power to explicitly model the defect dynamics at each scale. The team will exploit novel software techniques to link supercomputer simulations with visualization utilities and a suite of analysis tools. The assembly of these tools will form the Digital Material: a virtual laboratory to explore and develop new and elegant theories and models of defect dynamics which combine insights from many disciplines, and to test and validate those models over a wide range of length scales. The team will exploit emerging internet-based collaboration and control tools not only to expedite its own internal multidisciplinary collaborative research, but also to help lead and participate in collaborative efforts worldwide by developing and sharing open, general purpose, software components.%%%The ability to better understand and model materials will drive economic and technological advances in the next century, in fields including heavy industry, transportation, advanced materials design, and microelectronics. In particular, the manner in which materials deform, deteriorate and ultimately fail is a decades-old problem which is the focus of this research project. The investigators, with the support of the NSF KDI initiative, will use powerful computers, new theoretical ideas and methods, the World Wide Web and other emerging technologies to change the way that materials are modeled. Combining new tools will enable the investigators to develop fundamental new insights, which are at once intellectually exciting and technologically important.***