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Freeze-Cast Manufacturing of Stable Iron-Alloy Foams for Energy Conversion and Storage

用于能量转换和存储的稳定铁合金泡沫的冷冻铸造制造

基本信息

批准号：
2015641
负责人：
David Dunand
金额：
$ 41.6万
依托单位：
Northwestern University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-01 至 2024-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2015641&HistoricalAwards=false
关键词：
Freeze Cast Manufacturing Stable Iron

项目摘要

Freeze casting is a low-cost manufacturing technique for creating porous materials or foams. This award investigates freeze casting as a means to make iron-nickel, iron-cobalt, and iron-copper foams that help power batteries for storing energy on the electricity grid, or improve chemical looping technologies for capturing carbon dioxide emissions from power plants. By advancing the materials manufacturing for these applications, this project contributes to national energy security, climate action goals, and U.S. competitiveness in the advanced energy materials sector. The knowledge developed in freeze casting of porous materials also benefits other industrial sectors such as healthcare, via porous bone-replacement implants, and automotive and aerospace, via lightweight structures. One current limitation to using freeze-cast energy materials is that they degrade during use. To address this problem, this research investigates methods, such as adding an alloying element, to stabilize freeze-cast iron foams and increase their usable lifetime. The relationships between manufacturing parameters and materials performance lay the groundwork for optimization and commercialization of such freeze-cast alloys. This project actively promotes participation of women and underrepresented minorities in research and continues building interdisciplinary and international collaborations.In energy applications, such as high-temperature solid-oxide batteries or chemical looping combustion, iron-based redox materials rapidly degrade due to the repeated molar volume changes associated with oxidation/reduction reactions. The pore architecture of freeze-cast, lamellar foams is ideally suited to address this issue, as it provides space for each lamella to expand and contract freely, without constraints from neighboring lamellae. Nevertheless, mechanical degradation still occurs due to Kirkendall micropore formation from imbalanced diffusion fluxes and fracture/spallation of the oxide phase. Alloying iron foams with nickel, cobalt, or copper is investigated as a strategy to suppress the above degradation processes, by creating Ni-, Co- or Cu-rich ductile cores within the lamellae, and by making diffusional fluxes more balanced. In-situ synchrotron X-ray diffraction and nano-tomography are used to reveal the phase and microstructural evolution in these alloys during redox cycling. These in-situ studies are complemented by thermogravimetry, ex-situ redox cycling, and metallography studies. Lastly, CALPHAD, phase-field, and finite-element models are developed to help guide alloy and composition selection, with validation provided by experiment.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.

冷冻铸造是一种制造多孔材料或泡沫的低成本制造技术。该奖项研究了冷冻铸造作为一种制造铁镍、铁钴和铁铜泡沫的手段，这些泡沫有助于为电网储存能量的电池提供动力，或者改进化学循环技术，以捕获发电厂排放的二氧化碳。通过推进这些应用的材料制造，该项目有助于国家能源安全、气候行动目标和美国在先进能源材料领域的竞争力。在多孔材料的冷冻铸造中发展的知识也有利于其他工业部门，如医疗保健，通过多孔骨替代植入物，以及汽车和航空航天，通过轻量化结构。目前使用冷冻铸造能源材料的一个限制是它们在使用过程中会降解。为了解决这一问题，本研究探讨了添加合金元素等方法来稳定冻铸泡沫铁并延长其使用寿命。制造参数与材料性能之间的关系为该类合金的优化和商业化奠定了基础。该项目积极促进妇女和代表性不足的少数群体参与研究，并继续建立跨学科和国际合作。在能源应用中，如高温固体氧化物电池或化学环燃烧，铁基氧化还原材料由于与氧化/还原反应相关的反复摩尔体积变化而迅速降解。冻铸板层泡沫的孔隙结构非常适合解决这个问题，因为它为每个板层提供了自由膨胀和收缩的空间，而不受相邻板层的限制。然而，由于扩散通量不平衡和氧化相断裂/剥落形成的Kirkendall微孔，仍然会发生机械降解。用镍、钴或铜合金化泡沫铁作为抑制上述降解过程的策略被研究，通过在片层内产生富含Ni、Co或cu的韧性芯，并通过使扩散通量更加平衡。利用原位同步x射线衍射和纳米层析成像技术研究了合金在氧化还原循环过程中的物相和显微组织演变。这些原位研究由热重法、非原位氧化还原循环和金相学研究补充。最后，建立了CALPHAD、相场和有限元模型，以指导合金和成分的选择，并通过实验进行了验证。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。