This project is a collaboration between two of the leading research groups in the area of ultra-high temperature ceramics, namely the Institute for the Science and Technology for Ceramics (ISTEC) in Faenza, Italy and the Missouri University of Science and Technology in Rolla, MO. The team at ISTEC includes Dr. Frederic Monteverde and Dr. Diletta Sciti who are funded separately by the Consiglio Nazionale delle Ricerche (CNR) in Italy. The focus of the combined effort is on fundamental aspects of processing and microstructure of boride-based ceramics to improve their mechanical properties at elevated temperature. Boride ceramics, such as zirconium diboride, are currently capable of withstanding sustained mechanical loads over a range of temperatures but fail catastrophically under extreme loads and under the extreme thermomechanical conditions for which they are being researched and developed. Applications include thermal protection systems for hypersonic flight, containment materials and fuel forms for nuclear reactors, high-speed cutting tools for machining, and ultra-high temperature refractories for metal production. The focal point of this project is the development of a dual composite architecture designed to create a new paradigm of structural ceramics with superior mechanical properties at elevated temperatures and in extreme environments. The ability to utilize dual composite ceramics in commercial applications, in extreme environments, will provide improvements in both energy efficiency and sustainability of future systems such as hypersonic aircraft and molten metal containment.
TECHNICAL DETAILS: Utilizing the combined expertise of the research group at ISTEC in diboride-silicide ceramics and the processing and properties of hierarchical ceramic composites expertise of the research group at Missouri S&T, the goal of the project is the development of a new paradigm of dual composite ceramics with improved elevated temperature mechanical properties. Zirconium diboride that is liquid phase sintered with molybdenum disilicide is being used as a base composition for the dual composite ceramics, although the concept is broadly applicable to any thermodynamically compatible material system. The role of controlling the structure and microstructure of ceramics at multiple length scales (i.e., a dual composite architecture) on the elevated temperature mechanical behavior of boride-based ceramics is being investigated using experimental studies, physics-based models, and analytical characterization techniques. The project is timely based on the global need to develop new ceramic materials for applications in extreme environments. Furthermore, the outcome of the research has the potential to transform state of the art boride ceramics into ceramics capable of extending the lifetime and use temperature of ceramics for applications in extreme environments, including hypersonic flight vehicles, nuclear reactors, molten metal and glass containment vessels, and others. Finally, ceramic materials for extreme environments is an area of research and development that is highly specialized and in dire need of more trained scientists and engineers to lead future research efforts. The project is directly impacting this area of the ceramic field by facilitating the exchange of young, underrepresented researchers from both institutions and by directly training a graduate student and two undergraduate students in the processing, testing, and characterization of ceramics for use in extreme environments.
