High Strength Composite System for Ships

RT&L FOCUS AREA(S): General Warfighting Requirements TECHNOLOGY AREA(S): Materials / Processes OBJECTIVE: Develop a high strength composite material that meets U.S. Navy standards for Flame, Smoke and Toxicity Requirements. DESCRIPTION: Ship building programs throughout the U.S. Navy have begun to increase the use of composite structures throughout the ship, i.e., Landing Craft, Air Cushion (LCAC) and Ship-to-Shore Connector (SSC) ramps, LPD 17 mast, and DDG 1000 deckhouse. These composite structures offer lighter weight and better corrosion resistance than a similar metallic part. The composite systems include resin, filler fabric and the methodologies involved in building finished products in various forms with differing functions. To date, identification of composite material solutions have required either relaxation of Flame/Smoke/Toxicity (FST) requirements (outlined in NAVSEA MIL-STD-3020, ASTM E84 and ASTM E662), compromise in material strength (durability) or increase in weight. Fatigue life calculations are based on 270 x 106 cycles, using allowable material properties. The Navy is seeking a new composite material system that provides a more agile forward force maneuverability and posture resilience and all the benefits of using composites while still meeting structural requirements for strength and durability and maintaining Naval fire resistance performance requirements. PHASE I: Develop a concept for a composite system, which will meet FST requirements while allowing for the needed strength and durability characteristics. Demonstrate the feasibility of the concept in meeting Navy needs and establish that the concept can be developed into a useful product for the Navy. Feasibility will be established by coupon development, laboratory testing and demonstration of the materials. The Phase I Option, if exercised, will include the initial design specifications and capabilities description to build a prototype solution in Phase II. PHASE II: Based on the results of Phase I efforts and the Phase II Statement of Work (SOW), develop and test the new system prototype composite system. Test in accordance with NAVSEA MIL-STD-3020MIL-STD-3020, ASTM E84 and ASTM E662 as well as plastic, elastic and failure pull testing to demonstrate strength characteristics. Product performance will be demonstrated through prototype evaluation, modeling, analytical methods, and demonstration over the required range of parameters including numerous cycles. A Phase III development plan and cost analysis will be prepared to outline transition of the technology to Navy use. Provide detailed drawings, code and specifications in Navy-defined format. In addition, provide support to shepherd the new composite system through the Navy technical approval process. PHASE III DUAL USE APPLICATIONS: Support the Navy in transitioning the new composite system for Navy use on shipbuilding programs beginning with LCAC and SSC Air Cushioned Vehicles. Once a new composite system is validated it is expected to have impact across the full range of composite usage in the Navy. Commercial applications include all aspects of composites including aerospace, hovercrafts, airplanes, helicopters, ferries, the oil and mineral industry, automotive, cold climate research, and exploration. REFERENCES: Lv, Qiang, Huang, Jian-Qian, Chen, Ming-Jun, Zhao, Jing, Tan, Yi, Chen, Li and Wang, Yu-Zhong. Effective Flame Retardant and Smoke Suppression Oligomer for Epoxy Resin. Industrial & Engineering Chemistry Research 2013. https://pubs.acs.org/doi/abs/10.1021/ie400911r Chen, Xilei, Liu, Lei and Jiao, Chuanmei. Influence of Iron Oxide Brown on Smoke-Suppression Properties and Combustion Behavior of Intumescent Flame-Retardant Epoxy Composites. Advances in Polymer Technology, Winter 2015, Volume 34, Issue 4. https://onlinelibrary.wiley.com/doi/full/10.1002/adv.21516 MIL-STD-3020, DEPARTMENT OF DEFENSE STANDARD PRACTICE FIRE RESISTANCE OF U.S. NAVAL SURFACE SHIPS, 7 November 2007. http://everyspec.com/MIL-STD/MIL-STD-3000-9999/MIL-STD-3020_11625/ ASTM E84, Standard Test Method for Surface Burning Characteristics of Building Materials, 2007. https://www.astm.org/search/fullsite-search.html?query=ASTM%20E84& ASTM E662, Standard Test Method for Specific Optical Density of Smoke Generated by Solid Materials, 2007. https://www.astm.org/search/fullsite-search.html?query=e662&