Failure Mechanics of 2D Materials for Advanced Coatings and Composites

二维(2D)材料已经成为一种新的材料类别，有望对从航空航天结构到能量存储等关键应用做出颠覆性的改变。在过去的十年中，研究人员已经证明了单个2D纳米结构具有非凡的电、热和机械性能，其中最明显的是石墨烯，然而，成功地将其整合到大规模材料和设备中仍然是遥不可及的。尤其是，2D材料具有极高的强度和刚度以及极低的摩擦力，这使得它们非常适合作为复合材料中的涂层和增强体。尽管有这个巨大的希望，宏观材料的行为仍然受到在存在关键缺陷和暴露在循环载荷或界面滑动下抵抗破坏的能力的限制。在过去的十年中，二维材料的纳米力学研究主要集中在阐明其固有的力学性能(即强度、模数、摩擦)，而下一波密集的研究需要研究其与工程相关的失效特性，包括断裂韧性、疲劳寿命和磨损行为。拟议的研究计划旨在弥合最有希望的2D纳米材料与其在实际机械应用(即涂层和复合材料)中的应用之间的差距，方法是扩展对其内在力学行为的基本理解，包括与工程相关的特性(即断裂韧性、疲劳、磨损)，从而能够在存在临界缺陷和循环加载/滑动的情况下预测材料失效。该计划将采用多尺度方法，将最先进的实验纳米机械测试和纳米尺度的原子建模与微观和宏观最终用途材料测试和连续建模相结合。该计划将分为三个主要领域：i)功能化和非功能化2D材料的断裂韧性研究，ii)2D材料的疲劳循环失效和寿命研究，以及iii)2D材料在磨损状态下的摩擦学(摩擦和磨损)研究。该研究计划将弥补与宏观涂层和复合材料中2D材料的集成相关的机械故障现象的基本理解方面的关键空白。这三个推力领域的研究将为二维材料的破坏力学领域提供新的知识体系。这将最终导致涂层和复合材料性能的前所未有的进步，这将使加拿大航天/航空航天、汽车和能源储存领域的公司和组织受益。它将直接支持在跨学科培训环境中培训高素质人员，这种培训环境将利用独特的就地纳米力学研究基础设施和国际合作。

Two dimensional (2D) materials have emerged as a new class of materials that are expected to make disruptive changes to critical applications ranging from aerospace structures to energy storage. In the last decade researchers have demonstrated the extraordinary electrical, thermal, and mechanical properties of individual 2D nanostructures, most notably graphene, however the successful incorporation into largescale materials and devices remains elusive. In particular, 2D materials are know to exhibit extraordinarily high strength & stiffness as well as extraordinarily low friction making them highly desirable as coatings and reinforcements in composite materials. Despite this great promise, macroscopic materials behavior is limited by the ability to resist failure in the presence of critical defects and exposure to cyclic loading or interfacial sliding. While the last decade of nanomechanics research of 2D materials has focused on elucidating intrinsic mechanical properties (i.e. strength, modulus, friction), a next wave of intense research is needed to study their engineering relevant failure properties including fracture toughness, fatigue life, and wear behavior. The proposed RESEARCH PROGRAM aims to bridge the gap between the most promising 2D nanomaterials and their implementation in practical mechanical application (i.e. coatings & composite materials) by extending the fundamental understanding of their intrinsic mechanical behavior to include engineering relevant properties (i.e. fracture toughness, fatigue, wear) that enable prediction of materials failure in the presence of critical defects and cyclic loading/sliding. The program will employ a multiscale approach which combines state of the art experimental nanomechanical testing and atomistic modeling at the nanoscale with micro and macroscopic end use materials testing and continuum modeling. The program will be divided into three thrust areas; I) fracture toughness studies of functionalized and unfunctionalized 2D materials, II) fatigue cyclic failure and lifetime studies of 2D materials and III) tribology (friction & wear) studies of 2D materials in the wear regime. The research program will bridge critical gaps in the fundamental understanding of mechanical failure phenomena relevant to the integration of 2D materials within macroscopic coating and composite materials. The studies within the three thrust areas will provide a new body of knowledge in the area of failure mechanics of 2D materials. This will ultimately lead to unprecedented advancements in coating and composite materials performance which will benefit Canadian companies and organizations in space/aerospace, automotive, and energy storage sectors. It will directly support the training of highly qualified personnel within an interdisciplinary training environment which will leverage unique in situ nanomechanics research infrastructure and international collaboration.