QRM: Understanding the Mechanical Design of Natural Cellular Materials via a Multiscale Quantitative Structural Representation

许多生物材料系统，如木材、骨骼、海绵和海胆，利用细胞结构同时具有机械功能和重量减轻。同样，具有轻量化设计和机械效率的工程蜂窝固体在能源、基础设施、航空航天、生物医学和汽车行业的应用越来越受到青睐。虽然许多工程细胞材料被制造成具有完全随机或周期性晶格，但天然细胞材料通常表现出复杂的三维细胞设计，在多个长度尺度上具有可控的结构形态。这被认为有助于他们显著的机械稳健性，特别是考虑到他们的机械弱或软成分。该奖项将支持一项基础研究，通过涉及材料科学与工程、机械工程、计算机视觉和数据科学的综合多学科努力，阐明高性能天然细胞材料的多尺度结构基础。从天然细胞材料中获得的见解将为工程细胞材料的设计和制造提供重要指导，加深我们对结构细胞固体的理解，并为先进轻质材料和结构的设计和制造提供见解，对美国制造业和基础设施部门具有潜在的好处。这项工作将为自然系统中发现的高多孔结构的多尺度细胞网络建立一个定量、全面和有效的结构表示方案。研究人员将研究海胆刺的生物陶瓷细胞结构作为测试平台系统，多尺度结构表征将阐明其卓越的机械稳健性和损伤容忍度的基本理解。这项工作将通过三个主要创新来解决表示复杂、分层细胞结构的挑战，包括高分辨率断层成像和自适应压缩数据处理，细胞结构的多尺度表示（单个支柱和节点水平，局部单位细胞水平和全球细胞网络水平），以及在多个长度尺度上具有形态控制的生物启发细胞结构的硅“再生”。研究小组将通过系统的有限元模拟和基于同步加速器成像的原位力学测试进一步验证多层细胞结构表征。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Many biological materials systems, such as wood, bones, sponges, and sea urchins, utilize cellular structures for simultaneous mechanical function and weight saving. Similarly, engineering cellular solids with lightweight design and mechanical efficiency, have become increasingly favored for applications in energy, infrastructure, aerospace, biomedical, and the automotive vehicle industries. While many engineering cellular materials are manufactured to have either completely stochastic or periodic lattices, natural cellular materials often exhibit complex three-dimensional cellular designs with controlled structural morphologies at multiple length scales. This is believed to contribute to their remarkable mechanical robustness, especially considering their mechanically weak or soft constituents. This award will support a fundamental study to elucidate the multi-scale structural basis of the high-performance natural cellular materials, through an integrated multi-disciplinary effort involving materials science and engineering, mechanical engineering, computer vision, and data science. The insights gained from natural cellular materials will provide important guidance in the design and manufacturing of engineering cellular materials, deepen our understanding of structural cellular solids, and provide insights for the design and fabrication of advanced lightweight materials and structures, with potential benefits to US Manufacturing and Infrastructure sectors.This work will establish a quantitative, comprehensive, and efficient structural representation scheme for the multi-scale cellular network of highly porous structures found in natural systems. The researchers will study the bioceramic cellular structure of sea urchin spines as a testbed system, and multiscale structural representations will elucidate fundamental understanding of their remarkable mechanical robustness and damage tolerance. The work will address the challenges of representing complex, hierarchical cellular structures via three major innovations, including high-resolution tomography imaging and adaptive compressive data processing, multi-scale representation of the cellular structure (individual strut and node level, local unit-cell level, and global cellular network level), and in-silico "regrowth" of bio-inspired cellular structures with morphological control at multiple length scales. The research team will further validate the multi-level cellular structural representation through systematic finite element simulations coupled with synchrotron imaging-based in-situ mechanical testing.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.