N221-006 TITLE: Room-Temperature Filler for Honeycomb Repairs
OUSD (R&E) MODERNIZATION PRIORITY: General Warfighting Requirements (GWR)
TECHNOLOGY AREA(S): Air Platforms;Materials / Processes
OBJECTIVE: Develop and demonstrate a lightweight honeycomb core filler for repairs with a short, room room-temperature cure.
DESCRIPTION: Current composite honeycomb repairs rely on either epoxy fill, higher temperature cure (150-160° F; 65.56–71.11 °C) syntactic foams, or 7-day room-temperature cures of syntactic foam. These options have drawbacks, including long times to complete the repair, additional required equipment for controlling/monitoring the cure, and increased resultant weight for epoxy fill repairs. In addition, syntactic foams were designed for battlefield or non-aviation applications and lack the target room-temperature cure duration and required mechanical performance. Composite honeycomb repairs need to be simplified and streamlined to reduce repair turnaround time and necessary support equipment. Reducing the time to cure can drastically improve the rate at which repairs are completed, increasing fleet readiness. As an added benefit, development and qualification of a new repair material will offer an additional solution for repairs.
A new lightweight, streamlined composite honeycomb repair material and process using a novel lightweight, structural filler formulation is sought to reduce the time required for honeycomb repairs. The proposed material can take advantage of various matrix chemistries and fillers [Ref 1]. The repair material would be expected to meet threshold requirements, threshold mechanical properties, and target requirements.
Threshold requirements include, but are not limited to:
Threshold mechanical properties include, but are not limited to:
Target requirements include, but are not limited to:
PHASE I: Develop novel composite honeycomb filler formulations and screen candidate formulations for feasibility. This assessment can include cure kinetics (maximum exothermic temperature, cure time, pot life) and density to identify the most promising candidate formulations. The Phase I effort will include prototype plans to be developed under Phase II.
PHASE II: Develop and provide a prototype repair process (suitable for a Depot or I Level repair) using the developed repair material in Phase I. Complete a repair with a minimum size of 3 inches in diameter and 1.5 inches in thickness on a representative part with the developed honeycomb filler. Conduct, in coordination with the Government, mechanical and physical testing that includes a limited set of screening tests sufficient to ensure acceptable properties. Demonstrate reduction in overall cure time and compatibility with common naval aviation honeycomb materials.
PHASE III DUAL USE APPLICATIONS: Generate data for full qualification and validate the repair filler material and the repair technique. Repair instructions for Depot or I Level honeycomb repairs will be developed and provided. Transition the technology to applicable Navy Depot.
Honeycomb repair is applicable to composites outside of the aerospace industry. The automotive, as well as the marine industry, use honeycomb or filled-composite structures. A repair material that is effective across multiple industries is possible.
KEYWORDS: Composites; Honeycomb; Repair; Lightweight; Room temperature; Filler
** TOPIC NOTICE **
The Navy Topic above is an "unofficial" copy from the overall DoD 22.1 SBIR BAA. Please see the official DoD Topic website at rt.cto.mil/rtl-small-business-resources/sbir-sttr/ for any updates.
The DoD issued its 22.1 SBIR BAA pre-release on December 1, 2021, which opens to receive proposals on January 12, 2022, and closes February 10, 2022 (12:00pm est).
Direct Contact with Topic Authors: During the pre-release period (December 1, 2021 thru January 11, 2022) proposing firms have an opportunity to directly contact the Technical Point of Contact (TPOC) to ask technical questions about the specific BAA topic. Once DoD begins accepting proposals on January 12, 2022 no further direct contact between proposers and topic authors is allowed unless the Topic Author is responding to a question submitted during the Pre-release period.
SITIS Q&A System: After the pre-release period, proposers may submit written questions through SITIS (SBIR/STTR Interactive Topic Information System) at www.dodsbirsttr.mil/topics-app/, login and follow instructions. In SITIS, the questioner and respondent remain anonymous but all questions and answers are posted for general viewing.
Topics Search Engine: Visit the DoD Topic Search Tool at www.dodsbirsttr.mil/topics-app/ to find topics by keyword across all DoD Components participating in this BAA.