EAGER: Damage Evolution at the Fiber-Matrix Interphase for Early Failure Characterization in Composites

EARLY概念探索性研究（EAGER）奖支持基础研究，以了解疲劳失效如何起源于复合材料中纤维和基质之间的相互作用。复合材料是由一种以上的成分制成的材料，例如碳纤维或玻璃纤维置于塑料基质中。这种材料用于多种应用，包括飞机、汽车、桥梁，甚至高尔夫球杆。不幸的是，复合材料在承受循环载荷时可能会在几乎没有警告的情况下发生灾难性的失效。这被称为疲劳失效，并且很难预测。通过了解这种故障如何随着时间的推移而产生和发展，将有可能更好地预测复合材料制成的东西在断裂之前可以存活多久。这将使复合材料的使用更安全，更便宜，拯救生命，并使美国经济受益。该项目还将有助于扩大传统群体对科学和工程的参与。本研究的重点是发生在纤维-基体界面和聚合物基复合材料的界面区域内的微米和纳米尺度的劣化、损伤和失效机制的基本表征。然后，这些测量结果可用于开发基于力学的设计工具，这些工具将纤维表面改性对复合材料的疲劳寿命和耐久性的影响结合起来。这项研究是由最近开发的工具推动的，这些工具能够以“几十纳米”的空间分辨率进行这种直接测量。 这项调查还导致了一个更全面的项目，开发一个多尺度的损伤为基础的方法建模的纤维增强复合材料的长期耐久性。

This EArly-concept Grant for Exploratory Research (EAGER) award supports fundamental research to understand how fatigue failure originates at the interaction between fibers and matrix in a composite material. Composites are materials made from more than one component, such as carbon or glass fibers placed in a plastic matrix. Such materials are used in several applications including aircraft, automobiles, bridges, and even golf clubs. Unfortunately, composite materials can fail catastrophically with little warning when subjected to cyclic loading. This is known as fatigue failure and can be very difficult to predict. By understanding how this failure originates and grows over time it will become possible to make better predictions about how long something made from composites can survive before breaking. This will make composites safer and cheaper to use, save lives, and benefit the US economy. This project will also help broaden the participation of traditionally groups in science and engineering. This research focuses on a fundamental characterization of the micro- and nano-scale deterioration, damage, and failure mechanisms that occur at the fiber-matrix interface and within the interphase region of polymer matrix composite materials. These measurements could then be used to develop mechanics-based design tools that incorporate the effects of fiber-surface modification on the fatigue life and durability of composites. The research is driven by the development of recent tools that enable such direct measurements at spatial resolutions of `tens of nanometers'. This investigation also leads to a more comprehensive project to develop a multi-scale damage-based approach for modeling the long-term durability of fiber-reinforced composites.