Porous Hybrid Composite for Enhanced Thermal Protection Systems (ComTPS)

ABSTRACT: The proposed research will demonstrate feasibility of a high temperature insulating, load bearing thermal protection system (TPS) using a hybrid composite technology. This program will incorporate a hierarchically porous ceramic core material in a sandwich structure with a conventional polymer matrix composite (PMC) and ceramic matrix composite (CMC) to fabricate an enhanced TPS. This material will protect the underlying structure from high temperatures, variable heating rates (Mach 4-6), and loading schemes. The core will be fabricated using an inexpensive manufacturing process from a pre-ceramic polymer that can be tailored for thickness and gradient of porosity without a substantial increase in weight to the structure. During Phase II, the NextGen team will focus on the development of the core material in near-net shape form and optimization of thermal protection properties to withstand external temperatures of 2000F and internal temperatures of 600F. These properties will be modeled to predict thermal performance, and an integrated adhesion technique will be developed for 3-component structural assembly. Near-net shape prototypes will be manufactured and characterized in a relevant environment to verify mechanical and thermal properties of the core and 3-component part. Phase III will focus on commercialization of the technology for military and commercial applications. BENEFIT: The anticipated benefits of the porous hybrid composite thermal protection system include simultaneous thermal insulation and load-bearing capabilities and low density. The ceramic foam itself also has a lower thermal conductivity than that of the baseline SiC foam. Due to the unique fabrication and bonding/assembly methods to be developed, the structure will have good machinability in the pre-ceramic form, minimal required machining due to near-net shape casting and minimal volume shrinkage, and minimal outgassing of bonding agents from the integrated bonding approach. All of these factors and the low materials and equipment cost contribute to lower overall manufacturing cost. Additionally, the focus on near-net shape forming reduces assembly difficulties and expedites the integration process into subsystems and systems. Potential applications for this technology include high temperature structures such as hypersonic vehicles, ballistic missiles, various space structures, and re-entry vehicle parts. Other commercial products that would benefit from this technology include automobiles and commercial aircraft. The ComTPS technology could protect surrounding parts from the high temperatures produced by automobile and jet engines or be used as brake disks in aircraft or racecars.