STTR Phase I: Biomimetically Engineered Ceramics

这个小企业技术转让第一阶段项目旨在开发基于耐损伤贝壳微结构的工程陶瓷仿生结构。工程陶瓷材料的损伤容限差导致其在应力作用下产生灾难性的失效模式，限制了其结构实用性。 在极端条件下，陶瓷通常仅用作热或化学屏障。 通过相变增韧、针状晶粒和工程结构（如纤维整体（FM）），在选定的陶瓷中已获得损伤容限。 通过模仿Strombus Gigas（海贝壳）的微结构，可以实现进一步的显著收益。 海贝壳的多尺度结构将在由氮化硅和氮化硼组成的模型工程陶瓷系统中复制，这是通过借用和显著建立在制造FM所用的技术上，包括热塑性变形和组装。 将通过这些复杂的架构进行裂纹扩展的建模，以帮助指导该过程的发展。工程陶瓷的微观结构，机械和热性能的特点。这项研究将建立可行性的建议的热塑性变形/组装技术工程的三阶仿生陶瓷材料，预计将有一个工作的断裂两倍以上的大可比FM。更广泛的影响/商业潜力，该项目将是高度损伤容限陶瓷的发展，将增加其在工程应用中的实用性和验证生物启发材料工程。 仿生陶瓷将显著提高现有陶瓷系统的损伤容限，因此将引起许多行业的极大兴趣：制造业，军事/航空航天和医疗。 目前还没有一种类似的技术能够将陶瓷的优点（低密度、热稳定性、高硬度）与缺点（差的损伤容限）结合起来。 陶瓷和金属基复合材料比块体陶瓷提供更好的可靠性，但价格昂贵，往往达不到设计要求。 超坚韧陶瓷将在医疗植入物中产生更好的性能，保持美国制造业的领先地位，并促进先进的汽车技术。通过创造能够满足热和结构要求的材料，这项技术将创造更多的多功能陶瓷。 此外，该项目将导致通过损伤容限分层结构裂纹扩展的更好的理解。 最后，该项目将涉及维拉诺瓦大学的本科生和研究生，研究的主要成果将在多学科会议和期刊上传播。

This Small Business Technology Transfer Phase I project seeks to develop biomimetic structures in engineering ceramics based on the damage-tolerant sea shell micro-architecture. Poor damage tolerance of engineering ceramics leads to catastrophic failure modes under stress, which restricts their structural utility. In extreme conditions, ceramics generally function only as a thermal or chemical barrier. Gains in damage tolerance have been made in select ceramics via transformation toughening, acicular grains, and engineered architectures such as Fibrous Monoliths (FMs). Significant further gains can be achieved by mimicking the micro-architecture of the Strombus Gigas (sea shell). The multiscale architecture of the sea shell will be replicated in a model engineering ceramic system comprised of silicon nitride and boron nitride by borrowing and significantly building on the techniques used in making FMs, including thermoplastic deformation and assembly. Modeling of crack propagation through these complex architectures will be performed to help guide the development of the process. The microstructural, mechanical, and thermal properties of the engineered ceramics will be characterized. This research will establish the viability of the proposed thermoplastic deformation/assembly techniques to engineer a third-order biomimetic ceramic material which is expected to have a work-of-fracture more than twice as large as a comparable FM.The broader impact/commercial potential of this project will be the development of highly damage-tolerant ceramics that will increase their utility in engineering applications and validate bio-inspired materials engineering. The biomimetic ceramics will improve on the damage tolerance of existing ceramic systems by a significant margin and therefore will be of great interest to many industries: manufacturing, military/aerospace, and medical. No comparable technology exists which combines the benefits of ceramics (low density, thermal stability, high hardness) without their disadvantages (poor damage tolerance). Ceramic- and metal-matrix composites offer better reliability than bulk ceramics, but are expensive and often fall short of design requirements. Ultra tough ceramics will produce better performance in medical implants, maintain American manufacturing leadership, and promote advanced vehicle technology. By creating materials which can meet both thermal and structural requirements, this technology will create more multi-functional ceramics. Additionally, this project will lead to a better understanding of crack propagation through damage-tolerant hierarchical structures. Finally, the project will involve undergraduate and graduate students at Villanova University, and key results of the research will be disseminated in multidisciplinary conferences and journals.