Development of a Real-Time In Suit Organic/Elemental Carbon (OC/EC)

Not Available In order for solid rocket motors (SRMs) to achieve Integrated High Payoff Rocket Propulsion Technology (IHPRPT) goals of cost, reliability, mass fraction, and specific impulse, a significant improvement in throat materials must be made. Lightweight, economical, low-no/erosion throat materials are critical to achievement of those goals. Carbon/carbon (C/C) composites are used in this application; however, in tactical motors using advanced propellants, these components exhibit unacceptably high erosion and oxidation rates. And although the cost of C/C is lower than that of most ceramic matrix composites (CMCs), the relatively long densification times (weeks) coupled with the cost of fibers and preform fabrication makes the material too expensive for many applications. Therefore, the two primary problems preventing more extensive use of C/C in SRMs are survivability and cost. In previous work for the Air Force and NASA, Ultramet has demonstrated the outstanding thermal and oxidation performance of its patented Ultra2000TM hafnium carbide/silicon (Hfc/SiC) coating through arcjet testing of various coated carbon and CMC structures at the Air Force's Arnold Engineering Development Center and NASA's Ames Research Center. Surface temperatures as high as 4600 deg F have been achieved with no mass or dimensional change. The potential exists to increase the highly refractory HfC content within the coating in order to survive greater temperatures over the lifetime of an SRM. In this project, Ultramet proposes to team with the Air Force Research Laboratory (AFRL), which has developed a rapid and cost-effective means of producing quality C/C material, and the Chemical Systems Division of Pratt & Whitney, which will provide test facilities and commercialization expertise, in order to fabricate and test a coated C/C SRM nozzle with economic and performance capabilities that far exceed those of current materials.