Collaborative Research: DMREF: Topologically Designed and Resilient Ultrahigh Temperature Ceramics

Ultrahigh temperature ceramics are a class of materials with exceptionally high melting temperatures. Consequently, they hold great promise for extreme environment applications that include hypersonic flight, nuclear fusion reactors, and concentrated solar power. However, they are brittle at low temperatures, which negatively impacts functionality. Conversely, these materials deform too much at ultrahigh temperatures. Usually, one of these properties can be improved at the expense of the other, making optimization difficult. This Designing Materials to Revolutionize and Engineer our Future (DMREF) project will develop a new method to simultaneously improve both the low temperature and high temperature properties of these materials by devising a means to design and manufacture specific crystal structures and unique microstructures. As part of this research effort, the next generation of scientists and engineers will be trained in a cross-disciplinary manner as they work together to bridge different disciplines. This education will be expanded through an active high school and undergraduate summer program that identifies underserved demographics in STEM. Additionally, this project will educate secondary school teachers about materials science, and specifically ceramics, giving them the toolsets to integrate such information into physics, chemistry, and physical science courses dramatically broadening the impact of the science generated. The overarching goal of this project is to design ultrahigh temperature ceramics that are both resistant to fracture at low temperatures and resilient against creep at high temperature. This will be achieved by designing the ceramic from a bottom-up approach that utilizes the materials’ own natural length scales and chemistry to stabilize low symmetry crystal structures whose elongated shapes fit together creating an interlocked material microstructure. A combination of computational tools, including first principles and machine learning, will be integrated into experimental methods that directly synthesize customized powder morphologies where the structure and property performance is characterized. Through this iterative loop of interactions and outcomes, specific metal and nonmetal species will be identified and designed to promote desired phases with interlocking morphologies. By simultaneously improving toughness and deformation resistance in our ultrahigh temperature ceramics, this research will enable the advancement of technologies for use at extreme environments, while providing unique training for students in a multidisciplinary educational environment. 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.