MRI: Acquisition of High-Resolution X-Ray Computed Tomography System for Real-Time, In Situ Studies of Various Effects on Microstructure of Materials

这一重大研究仪器(MRI)奖支持收购高分辨率、四维(4D)X射线计算机层析成像(XCT)系统，以实现广泛的基础材料研究。所获得的知识将使新型和高性能材料的设计取得进展--导致智能和更具弹性的结构、更好的医疗和更高的能源效率。XCT系统还将支持密苏里州S和合作伙伴机构的教育、培训和外联活动，包括历史上的黑人林肯大学和塔斯基吉大学。这些活动包括对K-12学生和教师的培训，将该工具纳入课程，以及对研究生和本科生，包括伙伴机构任职人数不足的少数群体的个人进行跨学科培训和指导。材料的微观结构特征决定了其性能(例如，机械和运输性能)。任何给材料微观结构带来变化的外部或内部刺激--例如，机械载荷或化学反应--都会导致其性质发生变化。对材料中这种内在微结构-性能联系的了解可以揭示材料物理化学行为的起源，随后可以利用这些行为来优化其性能。XCT系统--由于其能够对各种材料的3D微结构进行现场实时表征--将推动与新材料(例如新型胶凝材料和形状记忆合金)的设计以及主流材料(例如玻璃和陶瓷；用于组织修复的生物材料；数字制造材料；以及能量存储和转换材料)的性能优化相关的许多领域的研究。有了这样的能力，XCT系统将使追求高风险-高回报的研究成为可能--例如，研究机械/热载荷或不希望看到的反应如何导致非均质多孔材料中微裂纹的萌生和扩展，以及这些裂纹将在多大程度上影响材料的传输特性。值得注意的是，XCT系统将促进旨在揭示微结构-性能联系的研究，并弥合以下方面的基本知识空白：表征新型二氧化碳高效粘结剂的早期反应和微结构发展；模拟额外制造的金属部件中气孔、熔合不足和其他缺陷的发展；制造用于硬度匹配的生物医学应用、精密作用力致动器和能量吸收装置的镍钛形状记忆合金定制部件；阐明核废料玻璃表面更改层中恶化的反应和传输现象；开发基于氧的反应性聚合物纳米颗粒疗法以治疗创伤性脑损伤；揭示了锂离子电池电极的3D内部微结构网络(具有亚微米分辨率)与离子和电子的传输以及相应的电池性能之间的基本关系。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This Major Research Instrumentation (MRI) award supports the acquisition of a high-resolution, four-dimensional (4D) X-Ray Computed Tomography (XCT) system to enable a broad range of fundamental materials research. The knowledge gained will enable advances in the design of novel and high-performance materials – leading to smart and more resilient structures, better medical treatments, and to enhanced energy efficiency. The XCT system will also support education, training, and outreach activities at Missouri S&T and partner institutions, including historically black Lincoln University and Tuskegee University. These activities include training of K-12 students and teachers, integration of the instrumentation into courses and interdisciplinary training and mentoring of graduate and undergraduate students, including individuals from underrepresented minorities at the partner institutions. Features of a material’s microstructure dictate its performance (e.g., mechanical and transport properties). Any external or internal stimulus that imparts changes to microstructure of a material – for example, mechanical load, or chemical reaction – invariably causes its properties to change. Knowledge of such intrinsic microstructure-property links in materials can reveal the origins of the materials’ physicochemical behavior, which can subsequently be capitalized on to optimize their performance. The XCT system – owing to its ability to perform in-situ, real-time characterization of 3D microstructure of materials of various types – will advance research in many areas relevant to design of new materials (e.g., novel cementitious materials; and shape memory alloys), and optimization of performance of prevailing materials (e.g., glasses and ceramics; biomaterials for tissue repair; digitally-fabricated materials; and energy storage-and-conversion materials). With such capabilities, the XCT system will empower the pursuit of high-risk-high-reward research – for instance, to study how mechanical/thermal loads or undesired reactions lead to initiation and propagation of microcracks in a heterogeneous porous material, and to what extent the cracks will affect the material’s transport properties. Significantly, the XCT system will facilitate research geared towards revealing microstructure-property links, and bridging fundamental knowledge-gaps in: characterizing the early stage reactions and microstructure developments in novel CO2-efficient cementitious binders; modeling the development of porosity, lack of fusion, and other defects in additively-manufactured metallic parts; fabricating bespoke components of nickel-titanium shape memory alloys for stiffness-matched biomedical applications, precision force actuators, and energy absorbers; elucidating the deteriorative reactions and transport phenomena in nuclear waste glass surface alteration layer; developing oxygen reactive polymer nanoparticle-based therapeutics to treat traumatic brain injury; and revealing the fundamental relationship between 3D internal microstructural network (with sub-micron resolution) of lithium-ion battery electrodes and the transport of ions and electrons, and correspondingly the battery’s performance.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.