Synergistic Modeling, Characterization, and Design of Embedded Phase Transforming Sensory Particles

对工程构件进行无损评估，以确定内部损伤是否存在，这对许多工程领域都是一个重要的过程。在与运输相关的领域尤其如此，在这些领域，安全至关重要，一个部件可能经历的装卸循环次数可能非常高，从而导致内部损坏。过度的内部损坏会导致失败，这是不可接受的。虽然内部损伤测量的现有方法确实存在，但一个由工程师和材料科学家组成的团队将探索一种新的方法，通过这种方法，以小颗粒的形式将微尺度损伤传感器直接嵌入关键部件。这些技术有望提高非破坏性评估的准确性，从而提高飞机、车辆、火车和潜在的其他重要交通基础设施的安全性。虽然该团队的方法适用于特定的工程挑战（内部损伤传感），但材料科学和应用数学和力学的发现也有望使从事各种先进材料开发的研究人员受益。作为这项研究的一部分，该团队还将向学生提供NASA和波音公司的专业机会，并通过暑期项目向K-12学生和教师开展拓展活动。该项目提出了一个新颖的概念：将固体传感粒子嵌入到金属结构中，通过强磁信号检测裂纹的产生和扩展。采用协同实验和计算方法，将具有多物理磁力耦合的形状记忆合金颗粒以小体积分量处理成结构部件，表征其磁响应，并将相关数据用于颗粒-矩阵连续体模型的制定和校准。这些模型将考虑感知颗粒的整体响应，它们与周围基质的界面，以及优化颗粒形状、大小、方向和分布的设计，以实现损伤的有效定位。这项工作的科学目标是：1)证明感觉粒子可以成功嵌入金属基体中，并在原位实验中提供磁性特征；2)获得关于粒子结构和发射响应的足够数据，以便校准和验证计算模型；3)生产经过验证的连续体建模工具，专门针对感觉磁性粒子的规模和响应进行定制。iv)提供基于结构成分的信息，关于颗粒如何在宿主成分矩阵中最佳分布。这项工作建立并扩展了在过去的努力中产生的初步结果，同时也探索了一种全新的传感机制。

The nondestructive evaluation of engineering components to determine the existence of internal damage is a process important to a wide range of engineering sectors. This is especially true in those sectors associated with transportation where safety is critical and the number of load/unload cycles a part might experience can be very high, resulting in internal damage. Excessive internal damage can lead to failure and is unacceptable. While a number of established methods for internal damage measurement do exist, a team of engineers and materials scientists will explore a new approach by which micro-scale damage sensors in the form of small particles are directly embedded into critical parts. These are expected to increase nondestructive evaluation accuracy, thereby increasing the safety of aircraft, vehicles, trains, and potentially other important transportation infrastructure. While the team's approach is applied to a particular engineering challenge (internal damage sensing), the materials science and applied mathematical and mechanics findings are also expected to benefit researchers working on a diverse range of advanced material developments. As part of this research, the team will also expose students to professional opportunities at NASA and Boeing, as well as perform outreach activities to K-12 students and teachers through summer programs. This project addresses a novel concept: embedding phase transforming solid sensory particles into metallic structures to detect the initiation and propagation of cracks via strong magnetic signals. A synergistic experimental and computational approach is taken, whereby shape memory alloy particles exhibiting multi-physical magneto-mechanical coupling are processed at low volume fractions into structural components, their magnetic responses characterized, and associated data employed in the formulation and calibration of particle-matrix continuum models. These models will consider the bulk response of the sensory particles, their interface with the surrounding matrix, and the design of optimized particle shape, size, orientation, and distribution for the effective location of damage. The scientific objectives of this work are to: i) demonstrate that sensory particles can be successfully embedded in a metallic matrix and provide magnetic signatures during in-situ experiments, ii) acquire sufficient data regarding particle configuration and emitted response so as to calibrate and validate computational models, iii) produce validated continuum modeling tools specifically tailored to the scale and response of the sensory magnetic particles, and iv) provide structural component-based information regarding how particles should be best distributed in the host component matrix. This work both builds upon and expands an enabling body of preliminary results generated in past efforts while also exploring an entirely new sensing mechanism.