TECHNOLOGY AREA(S): Materials/Processes

ACQUISITION PROGRAM: Strategic Systems Programs, ACAT I

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 with section 3.5 of 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 a scalable process to increase performance and consistency of natural wood as a structural material.

DESCRIPTION: Natural composites - wood - were the main structural components in the early years of Aerospace. Due to strength constraints and variability of a naturally sourced material, man-made composites soon started taking over the industry. Wood plies have the benefits of being radio frequency (RF) transparent and show little aging. An innovative process that expands the use of natural materials or wood species/types, while keeping the benefits of wood as a composite material, allows the program to continue to utilize previous designs.

Composite lay-up should have the following characteristics:
Nominal Thickness - 0.5 inch
Tensile Strength � Longitudinal > 8.0 ksi Property quantified
Bending Strength � Longitudinal > 5.0 ksi
Shear Strength > 1.6 ksi Property quantified
Internal material damping - Loss Factor = 0.01 or higher
Radio Frequency Transparent in the GigaHertz region of the electromagnetic spectrum (EM) spectrum
Manufacturability � Must be able to form into a complex curvature (doubly curved shell of revolution)
Service Life � capable of lasting longer than 25 years

PHASE I: Conduct a feasibility study for development of a suitable process to strengthen natural composite material that satisfies characteristics defined in the Description. Develop a method of fabrication for subscale articles. Identify technology and manufacturing development challenges and approaches to address during Phase II.

PHASE II: Develop, fabricate, demonstrate, and validate sub-scale component prototypes. Manufacture nine articles in sub-scale prototypes to characterize the capability of the technology and calibrate analysis models. Ensure that the manufacturing process demonstrates scalability and repeatability. Measure physical and mechanical properties and validate that they meet or exceed the characteristics provided in the Description. Conduct mechanical property testing of fabricated specimens and verify adequate performance to advance to full-scale representative components.

PHASE III DUAL USE APPLICATIONS: Provide support in transitioning the technology for Navy use in Strategic Systems Programs. Support the Navy with certifying and qualifying the system for Strategic Systems Programs use. Navy Strategic Systems Programs will provide the assets and test support as Government Furnished Equipment and Services.

Commercial companies that currently use man-made composites for radomes or structural components could find this natural composite as a possible replacement for the material.

REFERENCES:

1. Sarafin, Thomas P.� "Spacecraft Structures and Mechanisms--from Concept to Launch." Springer Netherlands, 1995. ISBN 0-7923-3476-0.

2. Lopatto, Elizabeth. "SpaceX even landed the nose cone from its historic used Falcon 9 rocket launch." The Verge, 31 March 2017. https://www.theverge.com/2017/3/30/15132314/spacex-launch-fairing-landing-falcon-9-thruster-parachutes

3. Harvey, Brian. "Europe's Space Programme: To Ariane and Beyond." London; New York: Springer; Chichester, UK: published in association with Praxis Pub., 2003. ISBN 1-85233-722-2.

4. Kumpel, A., Barros, P., Burg, C., Velleneuve, F. and Mavris, D. �A Conceptual Design for the Space Launch Capability of Peacekeeper ICBM.� Los Angeles, CA: Aircraft Technology, Integration, and Operations 2002 Technical Forum. https://www.researchgate.net/publication/27523123_A_Conceptual_Design_for_the_Space_Launch_Capability_of_the_Peacekeeper_ICBM

KEYWORDS: Strategic Missiles; Composite Materials; Materials Development; RF Transparent Structural Materials; Ultrastrong Materials; Super Wood; Densified Wood; Natural Composite Materials