High Temperature Materials for Solid Propulsion Pintles

OUSD (R&E) MODERNIZATION PRIORITY: Hypersonics TECHNOLOGY AREA(S): Materials; Weapons The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import of defense-related material and services, including export of sensitive technical data, or the Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls dual use items. Offerors must disclose any proposed use of foreign nationals (FNs), their country(ies) of origin, the type of visa or work permit possessed, and the statement of work (SOW) tasks intended for accomplishment by the FN(s) in accordance the Announcement. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws. OBJECTIVE: Develop pintle shaft materials for use in higher temperature controllable solid propulsion systems. DESCRIPTION: The Government desires solid propulsion systems with greater impulse and thrust for future systems. Increasing solid propellant burn temperatures, may achieve this goal but also creates thermal challenges for materials. Additionally, the combination of high temperature performance, low thermal conductivity, and high tensile strength significantly limits the selection of available materials for current pintles. This topic seeks improved materials for use in pintle shafts for controllable solid propulsion systems. A current state of the art material used in pintles is needled carbon silicon carbide (C/SiC). Proposers may focus on improving C/SiC or propose other innovative materials, such as ceramics, metallics, multilayered composites of multiple materials, etc. This topic seeks to exceed tensile properties over existing materials while decreasing thermal conductivity. For composites, the tensile strength in the cross ply direction should be >8ksi at room temperature and >12ksi at 1,000 C. The cross ply thermal conductivity should be less than 20 W/mK at these temperatures. The material must be capable of production to at least 10cm thick. For other materials, the above properties must all be present in one direction, and the tensile strength in other directions must exceed the values stated above. Proposers may assume that a separate material is used as a coating, cladding, or pintle tip to prevent excessive erosion of the pintle. Alternatively, unitary materials intended to make up the entire pintle shaft and tip are acceptable. Materials for coatings or claddings are outside of the scope of this topic. PHASE I: Evaluate feasibility of proposed material concept by modeling and simulation and/or proof of concept testing. Material formulation and/or coupon fabrication is recommended to provide evaluation of critical properties. Work with solid propulsion system developers to understand environments. PHASE II: Continue material and process development through design, analysis, and experimentation. Optimize processing parameters for yield and quality. Material testing should be conducted to validate material models and generate property databases. Demonstration in a representative environment is desired. Phase II should identify an insertion opportunity and conclude with a mature manufacturing process. PHASE III DUAL USE APPLICATIONS: Work with a solid propulsion system manufacturer to iteratively design and fabricate prototype components for high-fidelity testing in a relevant solid rocket motor environment for current or future missile defense applications. A successful Phase III would provide the necessary technical data to transition the technology into a missile defense application. REFERENCES: U.S. Missile Defense Agency. August 6, 2021. Missile Defense System. Retrieved from http://www.mda.mil/index.html. George P. Sutton. 2010. "Rocket Propulsion Elements." 8th edition, John Wiley & Sons Inc. James D. Beardsley. 1976. United States Patent #3,948,042, System for Controlling the Nozzle Throat Area of a Rocket Motor. KEYWORDS: Materials, Propulsion, Composites, Fiber Preforms