3D Printing of Ultra-High Temperature Ceramics
Abstract
Ultra-High Temperature Ceramics (UHTCs) are potential materials for high temperature applications in extreme environments (>2000 °C), such as scramjet engines, sharp leading edges, thermal protection system (TPS) for reusable re-entry vehicles. Applications of UHTCs have been limited by obtaining near net shaped structures without machining them post processing. The extensive interest, challenges and industrial needs have promoted implementation of additive manufacturing (AM) to produce free-form structures with not only complex external shapes, but also internal configurations designed for specific applications. The proposed research aims at obtaining the near-net shaped structures of UHTCs carbides focusing on TaC and ZrC systems. Carbides are most widely used UHTCs for hypersonic applications owing to their exceptional thermo-mechanical properties. ZrC owing to lower density ~6.7 g/cc and TaC owing to highest density ~14.3 g/cc to develop the process scheme for 3DP of UHTCs. The high-performance complex near net shaped UHTC components such as nozzles, and heat exchanges will be printed via digital light processing (DLP) technique. The balance between the solid-loading of UHTC and rheological properties of the slurry is crucial and challenging step to be able to obtain high quality printable UHTCpart. This includes flow properties including viscosity, and shear yield stress to determine the extent of solid-loading content ofUHTC for DLP printing. The study focuses on outlining a process scheme to develop a printable UHTC slurry (with high solid loading)in order to obtain dense component after debinding and sintering. A two-step a debinding process in nitrogen followed by air will be opted to carbonize the organic matter and removal of carbon (and thus resin), respectively. The selection of temperature for the debinding process is chosen in such a way to avoid oxidation of UHTC carbide. The usage of spark plasma sintering (SPS) will be calibrated as a pressure less technique in order to: (i) retain the shape of 3DP structures; (ii) retarded grain growth due to consolidation in short time (< 10 mins); and (iii) improved thermo-mechanical properties. The mechanical properties will be evaluated at a multi-length scale under static and dynamic conditions (nano to bulk). This way, we can postulate the active points of failure and failure mechanism in UHTC component. The failure analysis further supplemented by the finite element modelling (FEM) will help in designing components to mitigate failure. Further, the oxidation resistance under simulated re-entry conditions at ultra-high temperature (> 2500 °C) will be studied using a custom build high-speed plasma torch facility. The proposed work will develop foundation on the process-property-performance relationship on 3DP UHTC carbides. Results from the proposed research will be used to successfully commercialize UHTC-based structural components, including integration of UHTC wear components in large diesel engines; complex-shaped neutron shielding components in fission reactors; high burn-up fission reactor vessels; UHTC armor tiles, fixturing in combustor liners and nozzle divergent seals found on Navy, and Marine turbine engines. The research project will provide graduate and undergraduatestudents with extensive training on DoD-relevant technologies, and research skills to prepare them for their future careers as technical staff members or academic researchers.Approved for Public Release.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 24, 2023
- Source ID
- N000142312649
Entities
People
- Ambreen Nisar
Organizations
- Florida International University
- Office of Naval Research
- United States Navy