CAREER: Exploiting the Dynamic Dielectric Behavior of Water to Understand and Predict Polymer Composite Damage Progression

职业：利用水的动态介电行为来理解和预测聚合物复合材料的损伤进展

• 批准号: 1751482
• 负责人: Landon Grace
• 金额: $ 50万
• 依托单位: North Carolina State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-05-01 至 2024-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1751482&HistoricalAwards=false
• 关键词: CAREER; Exploiting; Dynamic; Dielectric; Behavior

This Faculty Early Career Development Program (CAREER) project will focus on improving the safety and performance of polymer composites by discovering the fundamental mechanisms governing the evolution of damage in these next-generation materials. Polymer composite usage is growing rapidly; driven by increasing demand for high-strength, lightweight materials in the automotive, aerospace, and civil infrastructure industries. In these primarily outdoor applications, loss of load-bearing ability over time is driven by material property changes in response to the complex and combined effects of mechanical and environmental stresses. A fundamental understanding of these changes is crucial to safe operation throughout the life cycle of the structure. To derive this understanding, the experimental approach in this research project takes advantage of changes in dielectric behavior of absorbed atmospheric water molecules in response to damage initiation and progression. By tracking the ability of water molecules to rotate in response to an oscillating electromagnetic field, early and non-visible changes in the chemical and physical characteristics of the material can be measured. The new and valuable insight into the mechanisms responsible for the progression of damage derived from these measurements will improve our ability to design more robust materials and better predict impending failure, thus advancing national health, prosperity, welfare, and national defense. The research will be complemented by an effort to provide access to K-12 summer engineering camp activities at North Carolina State University for students from rural and isolated urban communities. A sustainable process for packaging and disseminating these high-value educational resources will be developed and implemented, expanding their impact beyond the students attending the on-site camps and increasing visibility and knowledge of engineering among students who may not otherwise consider or pursue STEM careers.The overarching goal of the research is to derive the mechanistic underpinnings of polymer composite damage progression across spatial scales in response to coupled thermal, hygroscopic, and mechanical loading. The specific objectives in support of this goal are to: (i) describe the link between water-polymer interaction and topology, nanovoid content, polarity, and hygrothermal aging of fiber-reinforced epoxies; (ii) connect the response of absorbed molecular water to multiscale damage induced by dynamic, fatigue, and impact loading; (iii) use a neural-network technique to extract the salient variables that govern damage progression for use in deriving a mechanistic understanding of the molecular precursors to damage; and (iv) reconcile the experimental and neural-network derived insights with the physical basis of state-of-the-art multiscale, multiphysics simulation techniques. This project will allow the PI to expand the knowledge base in mechanics and materials science, enabling safer and more efficient use of polymer composites across multiple industries.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.

这个教师早期职业发展计划（职业）项目将着重于通过发现控制这些下一代材料损害演变的基本机制，以提高聚合物复合材料的安全性和性能。聚合物复合使用量正在迅速增长。受汽车，航空航天和民用基础设施行业中对高强度，轻质材料的需求不断增长的驱动。在这些主要是户外应用中，随着时间的推移，承重能力的损失是由材料特性的变化驱动的，这是对机械和环境应力的复杂和组合作用的响应。对这些变化的基本理解对于整个结构生命周期中的安全运作至关重要。为了获得这种理解，该研究项目中的实验方法利用了吸收大气水分子的介电行为的变化，以响应损害开始和进展。通过跟踪水分子响应振荡电磁场旋转的能力，可以测量材料的化学和物理特征的早期和不可见泊的变化。对负责从这些测量结果造成的损害进展的机制的新的有价值的洞察力将提高我们设计更强大的材料并更好地预测即将来临的失败的能力，从而促进国家健康，繁荣，福利和国防。这项研究将通过为北卡罗来纳州立大学的K-12夏季工程营地提供访问，以提供来自农村和孤立城市社区的学生的访问。 A sustainable process for packaging and disseminating these high-value educational resources will be developed and implemented, expanding their impact beyond the students attending the on-site camps and increasing visibility and knowledge of engineering among students who may not otherwise consider or pursue STEM careers.The overarching goal of the research is to derive the mechanistic underpinnings of polymer composite damage progression across spatial scales in response to coupled thermal, hygroscopic,和机械载荷。支持该目标的具体目标是：（i）描述水聚合物相互作用与拓扑，纳米接受纤维增强环氧氧化物的纳米类含量，极性和湿热衰老之间的联系； （ii）将吸收的分子水的响应与动态，疲劳和冲击负荷引起的多尺度损害的响应； （iii）使用一种神经网络技术来提取损害进展的显着变量，以用于推导对分子前体损害的机械理解； （iv）将实验和神经网络的洞察力与最先进的多尺度，多物理模拟技术的物理基础调和。该项目将使PI能够扩大力学和材料科学领域的知识基础，从而在多个行业中更安全，更有效地利用聚合物复合材料。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛影响的审查标准来评估的。

项目成果

Consequences of Humidity Cycling on the Moisture Absorption Characteristics of Epoxy Resins with Different Network Architectures

• DOI: 10.1021/acsapm.2c01570
• 发表时间: 2023-01
• 期刊: ACS Applied Polymer Materials
• 影响因子: 5
• 作者: Rishabh D. Guha;E. Danilov;Katherine Berkowitz;Oluwatimilehin E. Oluwajire;L. Grace

Nondestructive Examination of Polymer Composites by Analysis of Polymer-Water Interactions and Damage-Dependent Hysteresis

• DOI: 10.1016/j.compstruct.2022.115377
• 发表时间: 2022-02
• 期刊: Composite Structures
• 影响因子: 6.3
• 作者: O. Idolor;Katherine Berkowitz;Rishabh Debraj Guha;L. Grace

Damage Detection in Polymer Matrix Composites by Analysis of Polymer-Water Interactions Using Near-Infrared Spectroscopy

使用近红外光谱分析聚合物-水相互作用来检测聚合物基复合材料的损伤

• DOI: 10.12783/asc35/34874
• 发表时间: 2020
• 期刊: Proceedings of the American Society for Composites 35th Technical Conference
• 作者: IDOLOR, OGHENEOVO;GUHA, RISHABH;BERKOWITZ, KATHERINE;GRACE, LANDON
• 通讯作者: GRACE, LANDON

A MACHINE LEARNING APPROACH FOR IMPACT DAMAGE QUANTIFICATION IN POLYMER MATRIX COMPOSITES

聚合物基复合材料冲击损伤量化的机器学习方法

• DOI: 10.12783/asc37/36412
• 发表时间: 2022
• 期刊: American Society for Composites
• 作者: BERKOWITZ, KATHERINE;GUHA, RISHABH D.;OLUWAJIRE, OLUWATIMILEHIN;GRACE, LANDON
• 通讯作者: GRACE, LANDON

IMPACT DAMAGE DETECTION LIMITS OF MICROWAVE NDE TECHNIQUE FOR POLYMER COMPOSITES

聚合物复合材料微波无损检测技术的冲击损伤检测极限

• DOI: 10.12783/asc36/35933
• 发表时间: 2021
• 期刊: Proceedings of the American Society for Composites - Thirty-Sixth Technical Conference on Composite Materials
• 作者: BERKOWITZ, KATHERINE;GUHA, RISHABH D.;IDOLOR, OGHENEOVO;PANKOW, MARK;GRACE, LANDON
• 通讯作者: GRACE, LANDON