Collaborative Research: Computational and theoretical approaches for the morphological control of material microstructures

合作研究：材料微观结构形态控制的计算和理论方法

• 批准号: 0914720
• 负责人: John Lowengrub
• 金额: $ 15.16万
• 依托单位: University of California-Irvine
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-01 至 2013-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0914720&HistoricalAwards=false
• 关键词: Collaborative; Research; Computational; theoretical; approaches

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The investigator and colleagues study the prediction and morphological control of two-phase microstructures in solid/liquid and solid/solid diffusional phase transitions. Much of the research in this area is concerned with detailed and extensive studies of complex patterns such as dendritic growing shapes. In many applications (e.g. castings), it is desirable to control the formation of dendrites and grow compact shapes, which, however, has been much less studied. This project helps to fill the gap and aims to develop guidelines by which microstructures with desired shapes may be grown. The research team plans to (1) develop a suitable nonlinear theory of compact precipitate growth including existence, uniqueness, and stability of self-similar shapes; (2) develop and employ state-of-the-art adaptive 3D numerical methods to test the validity and limitations of theory; (3) compare theoretical and numerical results with existing experiments to test the validity of the mathematical assumptions and to verify the accuracy of predictions derived from the theory and simulations. Diffusional phase transformations deal with transformations of melts into precipitates (and vice-versa) as well as the separation of solids (e.g. metal alloys) into distinct phases. These phenomena have importance for a variety of processes including casting, welding and soldering, crystal growth, and related problems concerning protein and macromolecular crystallization. For example, crystal growth processes for technological applications began in the late 19th century, and form the cornerstone of virtually all modern semiconductor electronics and photonics today. The research activities will provide new mathematical theory and numerical simulations that can be used to develop guidelines for controlling the morphology of certain solidified materials. The new mathematical theory and adaptive numerical methods developed in the project have applications to a broader set of related problems including multiphase flows, biostructures and growth of solid tumors. In addition, this project will provide valuable interdisciplinary training opportunities for young researchers.

该奖项是根据2009年《美国复苏与再投资法》（公法111-5）资助的。研究者及其同事研究了固体/液体和固体/固体扩散相变的两相微观结构的预测和形态控制。该领域的许多研究都涉及对树突状形状等复杂模式的详细和广泛的研究。在许多应用（例如铸件）中，希望控制树突的形成并成长紧凑的形状，但是，研究的研究较少。该项目有助于填补差距，并旨在制定可能会增加具有所需形状的微观结构的准则。研究小组计划（1）开发一种合适的非线性沉淀生长理论，包括存在，独特性和自相似形状的稳定性； （2）开发并采用最新的自适应3D数值方法来检验理论的有效性和局限性； （3）将理论和数值结果与现有实验进行比较，以测试数学假设的有效性，并验证从理论和模拟中得出的预测的准确性。扩散相变的涉及熔体转化为沉淀物（反之亦然），以及将固体（例如金属合金）分离为不同的阶段。这些现象对于各种过程至关重要，包括铸造，焊接和焊接，晶体生长以及有关蛋白质和大分子结晶的相关问题。例如，技术应用的晶体生长过程始于19世纪后期，构成了当今几乎所有现代半导体电子和光子学的基石。研究活动将提供新的数学理论和数值模拟，可用于制定控制某些固化材料形态的准则。该项目中开发的新数学理论和自适应数值方法具有应用于更广泛的相关问题，包括多相流，生物结构和实体瘤的生长。此外，该项目将为年轻的研究人员提供宝贵的跨学科培训机会。