TECH FOCUS AREAS: General Warfighting Requirements (GWR) TECHNOLOGY AREAS: Sensors; Materials; Air Platform OBJECTIVE: The objective is to provide material and process options for extremely high temperature aperture applications. Efforts may focus on development of new materials options and approaches, process improvement of existing but immature aperture materials, or manufacturing process development of well-established materials. The candidate material(s) should be validated through a range of mechanical, thermal, and electrical tests, at various times throughout the effort. For a material maturation focused effort, validation should include a demonstration of the ability to fabricate representative sized components (e.g., a 6 x 6 doubly curved panel, or 3 diameter hemisphere) by the end of the effort. The component should then be tested in a relevant environment. For a manufacturing focused effort, manufacturing of a full-scale relevant geometry aperture shall be performed to prove the process. Testing should also assess the transient aerothermal and electromagnetic performance in a relevant environment. The resulting aperture technology will be validated under these efforts and data and concepts provided for transition to the programs of interest. To be viable, a component must not recess more than 1 mil/min during exposure to high heat flux tests which result in material temperatures well in excess of 1000 C. Electromagnetic properties such as signal transmittance must be measured and shown to be at least 80% of other state-of-the-art options. Ideally the improved manufacturing will also provide improved properties such as strength or erosion resistance as a result of reduction of variability due to controlled manufacturing processes. DESCRIPTION: The Air Force must be able to operate effectively in anti-access, area-denial environments as well as be able to disseminate real-time intelligence, surveillance, and reconnaissance data. This requires current and next generation ground, air, and space platforms to have antenna and aperture systems with improved bandwidth, capability, functionality, selectivity, and performance. This need is accentuated for vehicle platforms that travel at hypersonic speeds due to the additional requirement for the apertures to survive in high temperature and high sheer environments. Hypersonic platforms represent an extremely challenging combination of design requirements for window and radome materials. Necessary attributes include oxidation resistance, desirable electrical performance over a wide wavelength range, sand and rain erosion resistance, stable performance over a wide temperature range, high strength and toughness, robust processing, reasonable cost, and the ability to be integrated into the vehicle platform. These apertures are most desirably placed at or near the front of the vehicle, where temperature can reach or exceed ~1800 C for short (~20-60 sec) times. Commercial hypersonic platforms, assuming their successful development and the emergence of a viable business case, will require a range of apertures to meet various communications and sensing needs, but these can be placed in locations where they will experience much less extreme conditions, making extremely high temperature apertures a defense unique requirement. The high temperature composite and monolithic materials that are typical candidates for these types of applications have a long history of being expensive, poorly understood, slow and difficult to manufacture, and exhibiting significant lot-to-lot variability. A goal here is to identify new or improved materials and processes, mature the processing of the candidate material(s), and to increase the manufacturability, producibility, and reliability for current and next generation aperture systems. No single proposal will be able to accomplish all of this, so bidders should discuss the development status of their proposed material(s) and processing and clearly indicate where their focus lies development of a new material candidate, maturation of an existing material candidate, or manufacturing and producibility improvement of a well-established material and process. The proposed aperture system can include Radio Frequency (RF), Electro-Optic (EO), Infrared (IR), or multispectral solutions. New and innovative material solutions may be proposed to provide new options for extreme temperature apertures. Potential candidates include but are not limited to advanced monolithic and composite material variants. Processing approaches could include any of the range of traditional ceramic and composite processing approaches, additive manufacturing, and other innovative and unique techniques. Established but immature aperture materials may be proposed with a focus on addressing outstanding processing issues. The goal here is to identify any process deficiencies (e.g., failure to control all of the key process parameters; failure to ensure the consistency and suitability of all constituents) and seek to remedy them. Tools such as Expert Elicitations and Designed Experiments should be used to solve such problems. Application of an in-process non-destructive evaluation (NDE) technique, or some new measurement may be necessary to gain the understanding needed to resolve such an issue. Well established materials and processes may be proposed with a focus on improving the manufacturability, producibility, and reliability for current and next generation aperture systems. The focus is on reducing cycle time, part count, touch labor, and ultimately reducing the cost of the components while at the same time reducing manufacturing variability. An integrated manufacturing chain is required to overcome state-of-the-art geometric, material set, and part size limitations. To meet this need, advancements in areas that combine two or more aspects such as multi-material solutions, 3D printing techniques, innovative fiber preforming, engineered and localized property performance, automation, and improved densification techniques are sought. The work should be conducted with consultation or support from a hypersonics Prime vehicle manufacturer that can provide guidance on performance requirements and design considerations such as part size and relevant geometry. The proposal should clearly identify the current state of the art of the aperture system of interest including both technical and manufacturing readiness and how the proposed work will advance readiness for the proposed aperture concept. PHASE I: This topic is intended for technology proven ready to move directly into a Phase II. Therefore, a Phase I award is not required. The offeror is required to provide detail and documentation in the Direct to Phase II proposal which demonstrates accomplishment of a Phase I-like effort, including a feasibility study. This includes determining, insofar as possible, the scientific and technical merit and feasibility of ideas appearing to have commercial potential. PHASE II: Eligibility for D2P2 is predicated on the offeror having performed a Phase I-like effort predominantly separate from the SBIR Programs. Under the Phase II effort, the offeror shall sufficiently develop the technical approach, product, or process in order to conduct a small number of advanced manufacturing and/or sustainment relevant demonstrations. Identification of manufacturing/ production issues and or business model modifications required to further improve product or process relevance to improved sustainment costs, availability, or safety, should be documented. Air Force sustainment stakeholder engagement is paramount to successful validation of the technical approach. These Phase II awards are intended to provide a path to commercialization, not the final step for the proposed solution. PHASE III DUAL USE APPLICATIONS: The contractor will pursue commercialization of the various technologies developed in Phase II for transitioning expanded mission capability to a broad range of potential government and civilian users and alternate mission applications. Direct access with end users and government customers will be provided with opportunities to receive Phase III awards for providing the government additional research & development, or direct procurement of products and services developed in coordination with the program. NOTES: 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 proposed tasks intended for accomplishment by the FN(s) in accordance with the Announcement and within the AF Component-specific instructions. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws. Please direct questions to the Air Force SBIR/STTR Help Desk: usaf.team@afsbirsttr.us REFERENCES: Harris, Daniel C. Materials for infrared windows and domes: properties and performance. Vol. 158. SPIE press, 1999. ISBN 0-8194-3482-5 https://multimedia.3m.com/mws/media/1324013O/oxide-oxide-ceramic-matrix-composites.pdf https://www.quartz.saint-gobain.com/news/using-quartz-fiber-aerospace-radomes KEYWORDS: Extremely high temperature aperture applications; materials; manufacturing process; validated through a range of mechanical, thermal, and electrical tests; fabricate representative sized components (e.g. a 6 x 6 doubly curved panel, or 3 diameter hemisphere); relevant environment; transient aerothermal and electromagnetic performance; exposure to high heat flux; 1000 C; Electromagnetic properties; signal transmittance
