Architectured and bioinspired materials to expand property space

对结构性能的不断提高的要求推动了更坚固、更韧性和更轻的材料的发展。尽管材料科学取得了快速进步，但仍有一些性能组合是不可用的。例如，韧性和强度仍然是相互排斥的特性，硬保护和顺应性很难结合起来。*这项拟议的研究旨在利用两个强大的概念：建筑和生物灵感来扩大材料属性空间。建筑材料是介于微观结构和整体构件之间的具有长度尺度可控结构的高信息材料。在拟议的研究中感兴趣的是密集的建筑材料，由二维或三维排列的大小和形状明确的积木组成。这些积木很硬，但它们的界面较软，可以引导巨大的非线性变形和裂缝。这些原理导致了可以滑动、旋转、分离或联锁的积木，提供了丰富的可调机构、结构特性和功能。这项拟议研究的另一个重要概念是生物灵感。骨骼、牙齿或软体动物贝壳展示了僵硬的积木和非线性界面之间的相互作用如何产生非同寻常且极具吸引力的刚性、强度和韧性的组合。其他天然的建筑材料，如鳞状皮肤和鳍，展示了如何将硬和软结合在一起，以制造具有肌腱般的效果或变形能力的灵活外骨骼。*在拟议的计划中，我们将描述坚硬生物材料和系统的结构、性能和力学特性，包括牙齿、骨骼、软体动物贝壳、节肢动物角质层、鳞片和鳍。这项活动将涉及最先进的实验(小规模和现场、数字图像相关、高速成像、立体成像和三维重建)。我们还将为这些材料开发理论和数值模型(有限元、离散元)，以捕捉关键的架构和机制。这项活动将探索与建筑材料中长度尺度的分离和特性的均质化有关的基本和关键问题。这些模型将被纳入生物灵感建筑材料的设计和优化方案中。最后，我们将结合自下而上的制造策略(3D打印)和自上而下的方法(二维和三维激光雕刻)来制造和测试原型。*该计划将产生的新的生物灵感材料将在加拿大经济中具有高度影响力的各种应用(生物医学、航空航天、汽车、能源)，该计划将为各级高素质人才提供强有力的培训环境。

Ever-increasing requirements for structural performance drive the development of stronger, tougher and lighter materials. Despite rapid progress in materials science, there are still combinations of properties which are not available. For example toughness and strength remain mutually exclusive properties, and hard protection and compliance are difficult to combine. ***The proposed research aims at expanding material property space using two powerful concepts: architecture and bioinspiration. Architectured materials are high-information materials with controlled structures at length scales which are intermediate between microstructure and whole component. Of interest in the proposed research are dense architectured materials, made of building blocks of well-defined size and shape arranged in two or three dimensions. These building blocks are stiff, but their interfaces are softer and can channel large nonlinear deformations and cracks. These principles lead to building blocks which can slide, rotate, separate or interlock collectively, providing a wealth of tunable mechanisms, structural properties and functionalities. Another powerful concept central to the proposed research is bioinspiration. Bone, teeth or mollusc shells demonstrate how the interplay between stiff building block and non-linear interfaces generate unusual and highly attractive combinations of stiffness, strength and toughness. Other natural architectured materials such as scaled skins and fins demonstrate how hard and soft can be combined to make flexible exoskeletons with tendon-like effects or morphing capabilities. ***In the proposed program we will characterize the structure, properties and mechanics of hard biological materials and systems including teeth, bone, mollusk shells, arthropod cuticles, scales and fins. This activity will involve state-of-the-art experiments (small-scale and in-situ, digital image correlation, high speed imaging, stereo-imaging and 3D reconstruction). We will also develop theoretical and numerical models (finite elements, discrete elements) for these materials to capture key architectures and mechanisms. This activity will explore fundamental and critical questions related to separation of length scales and homogenization of properties in architectured materials. These models will be incorporated into design and optimization schemes for bioinspired architectured materials. Finally we will fabricate and test prototypes by combining bottom-up fabrication strategies (3D printing), with top-down approaches (two and three-dimensional laser engraving). ***The new bioinspired materials which will emerge from this program will have a variety of applications with high impact in the Canadian economy (biomedical, aerospace, automotive, energy), and the program will provide a vigorous training environment for highly qualified personnel at all levels.