Self Repairable Seals by Crack Healing of Glass and Glass-Ceramic Composites for Solid Oxide Fuel Cells

这项资助的主要目标是建立对有前途的玻璃和玻璃陶瓷复合材料中裂纹愈合机制的基本理解，这有助于推进燃料电池自修复密封件的变革性概念。 玻璃被用作固体氧化物燃料电池（SOFC）的密封件，用于直接发电。 它需要在800°C下工作的气密金属陶瓷密封件，这是一个挑战，并且在操作过程中容易出现玻璃密封开裂。 为了应对这一挑战，将寻求一种由表面能驱动的主动自修复密封的新概念。 这种新概念背后的基本原理是，在800°C的SOFC工作温度下，具有适当表面和热物理性质的密封玻璃可以愈合或修复在热瞬变期间产生的裂纹。 然而，目前缺乏对玻璃和玻璃陶瓷复合材料中裂纹愈合的动力学和机制的基本理解。 有了这样的理解，人们可以识别裂纹愈合/自修复机制，并能够预测在功能性SOFC中实现自修复所需的愈合时间。 此外，将更好地理解由玻璃结晶产生的或为了影响裂纹愈合行为而有意添加的结晶陶瓷相的作用，使得可以设计具有最佳承载能力和自修复性的玻璃-陶瓷复合材料以用作SOFC中的密封件。 通过这笔资金，PI还将开发分析模型，以描述和预测实验观察到的裂纹愈合和自修复行为。密封件在多个高科技领域发挥着关键作用，包括SOFC，真空技术，微电子学，电力电子学和微机电系统。 拟议的研究将培养研究生和本科生以及博士后助理，掌握适用于学术界和工业界的宝贵技术和研究技能，并通过用于高科技应用的玻璃和玻璃复合材料合成的新设施来推进我们机构的资源。 此外，由于目前的重点是保护我们有限的自然资源用于能源生产，高效的固体氧化物燃料电池将通过降低发电燃料消耗和环境影响而直接节省能源。 少数民族/女性本科生和高中生将通过多元文化工程计划（MEP）和WEAT（女性工程，建筑技术）计划接受指导和接触这项研究。 建议通过ASM材料讲习班和师生营，向高中开展重要的外联活动。

The primary objective of this grant is to establish a fundamental understanding of the crack-healing mechanism in promising glasses and glass-ceramic composites useful for advancing a transformative concept of self-repairable seals for fuel cells. Glasses are used as seals in solid oxide fuel cells (SOFCs) for generating electricity directly. It requires hermetic metal-ceramic seals functioning at 800°C, which is challenging and susceptible to glass seal cracking during operation. To address this challenge, a novel concept of active self-repairable seals driven by surface energy will be pursued. The rationale behind this novel concept is that at the SOFC operating temperature of 800°C a sealing glass with appropriate surface and thermophysical properties can heal or repair cracks created during thermal transients. However, a fundamental understanding of the kinetics and mechanism of crack healing in glasses and glass-ceramic composites is currently lacking. With such an understanding, one can identify the crack-healing/self-repair mechanism and be able to predict the healing time required for achieving self-repair in a functioning SOFC. In addition, the role of the crystalline ceramic phase created either by crystallization of the glass or added intentionally for influencing crack healing behavior will be better understood so that the glass-ceramic composites with optimum load-bearing capability and self-repairability can be designed for use as seals in a SOFC. Through this grant, the PI also will develop analytical models to describe and predict crack-healing and self-repair behaviors observed experimentally.Seals play a critical role in several high-technology areas including SOFCs, vacuum technology, microelectronics, power electronics, and microelectromechanical systems. The proposed research will train graduate and undergraduate students and postdoctoral associates in invaluable technical and research skills applicable to both academia and industry and advance the resources of our institution by new facilities for the synthesis of glasses and glass-composites for high-technology applications. In addition, with the current emphasis on conserving our limited natural resources for energy production, efficient SOFCs will result in direct savings by lower fuel consumption for power generation and environmental impact. The minority/women undergraduate and high school students will be mentored and exposed to this research through Multicultural Engineering Program (MEP), and WEAT (Women In Engineering, Architecture & Technology) programs. A significant outreach to high schools is proposed through ASM materials workshops and camps for teachers and students.