SBIR Phase I: Designing an Immune System Response Into High-Temperature Ceramic Matrix Composite Materials (CMC)

这个小型企业创新研究第一阶段项目旨在评估一种为碳化硅(SIC)纤维设计的新型相间纳米涂层，该涂层旨在为暴露在氧化环境中的高温陶瓷基复合材料(CMC)发挥仿生免疫系统的作用。高温CMC必须经受住氧化和热机械要求，而即使是最先进的高温合金也无法承受这些要求。界面涂层在实现这些目标方面起着至关重要的作用。界面涂层只占CMC质量的一小部分，但它们的大部分优异性能都要归功于界面涂层。这些涂层将纤维与基质以及彼此隔离，通过调节纤维和基质之间的载荷传递来控制失效机制，并作为环境屏障涂层(EBC)来保护承载纤维。本质上，界面涂层首先是一种微机械系统，旨在减少故障、防止氧化和轻微的自我修复。这项第一阶段的工作旨在增强这些功能，并为它们增加一种物质的“免疫反应”，能够在局部检测到氧气入侵，然后是自动成分变化，阻止进一步的氧气进入，最后是产生“疤痕组织”，使该区域对未来的氧化更具抵抗力。该项目的更广泛的影响/商业潜力将首先体现在高温陶瓷基复合材料组件的安全性和可靠性方面，例如在喷气发动机、燃气轮机或核电站中使用的高温陶瓷基复合材料组件。拟议的纳米涂层技术是由一种新的纤维制造平台技术实现的，该技术允许单一工艺完成目前需要两个独立的、非常昂贵的工艺。因此，碳化硅(SIC)纤维增强的CMC的成本可以降低，同时提供显著提高的质量。事实上，拟议的技术最终使我们有可能将负担得起的高质量碳化硅纤维引入我们的目标市场。这些市场包括军事和航空航天(涡轮机械、火箭、先进结构)、汽车、能源和其他行业，这些行业需要具有非凡强度、刚性、耐热性和/或耐化学性的先进材料。单是碳化硅纤维，即使不考虑这种涂层，也代表着一个具有巨大潜力的快速增长的市场，其总规模超过20亿美元。能够实现拟议的相间涂层的技术的能源足迹是竞争方法的千分之一，并且产生的相关废物和排放也只有一小部分。这提供了巨大的成本优势以及质量和性能的戏剧性改进。

This Small Business Innovation Research Phase I project is designed to evaluate a novel interphase nanocoating designed for Silicon Carbide (SiC) fibers, which is intended to behave as a biomimetic immune system for high-temperature Ceramic Matrix Composites (CMCs) exposed to an oxidizing environment. High-temperature CMCs must survive oxidative and thermomechanical requirements that even the most advanced superalloys cannot withstand. Interphase coatings play a critical role in achieving these objectives. Interphase coatings represent a tiny fraction of the mass of a CMC, but are responsible for most of their outstanding properties. The coatings isolate fibers from the matrix and from each other, control failure mechanisms by regulating load transfer between fiber and matrix, and serve as an Environmental Barrier Coating (EBC) to protect the load-bearing fibers. In essence, an interphase coating is first and foremost a micromechanical system engineered for failure mitigation, oxidation prevention, and a slight self-healing. This Phase I effort aims to enhance these functions and add to them a material "immune response" capable of local detection of oxygen intrusion, followed by automatic compositional changes which resist further oxygen ingress, and finally the creation of "scar tissue" that leaves the area more resistant to future oxidation. The broader impact/commercial potential of this project will first be felt in terms of enhanced safety and reliability of high-temperature Ceramic Matrix Composite components used, for example, in jet engines, gas turbines, or nuclear power plants. The proposed nanocoating technology is made possible by a new fiber manufacturing platform technology, which allows a single process to accomplish what currently requires two separate, very expensive, processes. The cost of Silicon Carbide (SiC) fiber-reinforced CMCs can therefore be reduced while delivering drastically improved quality. Indeed, the proposed technology finally makes possible the introduction of affordable high-quality SiC fibers to our target markets. These markets include military and aerospace (turbo machinery, rockets, advanced structures), automobile, energy and other industries that require advanced materials with exceptional strength, stiffness, heat resistance, and/ or chemical resistance. SiC fibers alone, even without considering this coating, represent a fast-growing market with great potential, the collective size of which exceeds $2 billion. The technology enabling the proposed interphase coating has an energy footprint that is 1/1000th that of competing methods and which produces a fraction of the associated waste and emissions as well. This provides a huge cost advantage as well as a dramatic improvement in quality and performance.