SITIS Archives - Topic Details
Program:  SBIR
Topic Num:  AF071-109 (AirForce)
Title:  Nickel-free Conductive Fillers
Research & Technical Areas:  Materials/Processes

  Objective:  Identify and demonstrate a nickel-free filler and/or conductive filler coating to meet current fighter aircraft performance requirements.
  Description:  Current fighter aircraft incorporate conductive materials to control the radar signature of the vehicle. Many of these materials employ the use of nickel or nickel coated fillers to provide the corrosion resistance necessary for the aircraft’s various operational environments. Unfortunately, nickel is a hazardous material and requires additional health and safety handling procedures during many steps in the installation process. Environmental, safety and health regulatory impacts include limitations on application equipment and controls as well as allowable worker exposure. Elimination of nickel used in gap fillers, fastener fillers, and nonwoven mat materials, and identification of filler and/or conductive filler coatings that will meet signature and corrosion resistance requirements would provide the aircraft program with cost affordability through environmentally friendly material. Current research is being done to substitute metals such as silver and gold for nickel. Proposals that continue these efforts or are unique in the area of processing will be considered. Other areas for new research may include refractory transition metal compounds.

  PHASE I: The objective of this task is to identify alternate nickel candidate materials and conduct preliminary feasibility screening tests. The identified tests will be performed, resulting in no more than two candidate materials for formulation and further material characterization. Baseline materials may include Toho Besfight MC Type II Nickel Coated Carbon Fiber or similar commercially available fibers. Expected approximate performance properties are electrical resistivity 3.5e-005 ohm-cm, tensile strength 3000MPa, elongation to break 1.5%, and tensile modulus 215 GPa.
  
  PHASE II: The objective of this phase is to formulate and optimize a material (fastener fill, gap filler or nonwoven mat) with the candidates identified in task 2 and perform detailed material characterization to determine if the candidate material is suitable for use in LO materials. The material characterization shall include chemical, mechanical, corrosion and electrical property evaluation.

  DUAL USE COMMERCIALIZATION: Military application: Nonnickel conductive filler materials may be utilized by aircraft manufacturers and repair facilities that have established requirements for this technology. Commercial application: Nonnickel conductive filler materials may utilized by aircraft manufacturers that currently use or plan to use nickel in commercial aircraft.

  References:  1. Pai, BC and Kulkarni, AG and Bhasker, TA and Balasubramanian, N (1980) Coating structure of metal-coated carbon fibres. Journal of Materials Science, 15 (7). pp. 1860-1863. ISSN 0022-2461 2. Deng, Yuliang; Wu, Ji ;Pecht, Michael; Butler, Michael; Swift, Joseph and Wallace, Stanley, Carbon Fiber Electrical Interconnects, 38th International Symposiumon Microelectronics, Emerging Technologies, pp. 169-176, Philadelphia, PA, September 25-29, 2005 3. Larry Rupprecht, Editor, Conductive Polymers and Plastics, RTP Company ISBN 1-884207-77-4, June 1999

Keywords:  nickel, nonnickel, filler, gap, conductivity

Additional Information, Corrections, References, etc:
NickelCoatedFiber.pdf
NickelCoatedFiber.pdf

Questions and Answers:
Q: 1. Can you send a few pictures of the areas we would be filling or repairing?

2. Does this filler need to be made out of a certain material?

3. Can we request sample parts - small areas to work on during our research phase?

4. Can you supply the data on what primer/top coat will be used?
A: 1. I have no pictures of the areas that need to be filled. The materials being looked at are plies of nickel coated carbon fibers in epoxy resins, mats of short nickel coated fibers in epoxy resins and chopped nickel coated fibers in thermoplastic resins. The areas to be filled or repaired are not as important as the replacing of nickel coating on the carbon fiber. I have posted to SITIS two pictures of a coated fiber and a coated carbon fiber tow.

2. A coated carbon fiber is required for the composite plies, and mat. The fastener filler has been qualified for chopped nickel coated carbon fiber and anything other than carbon fiber would require additional qualification that was not planned for this program. That said, other materials will be considered.

3. No sample parts are available.

4. No. I have no data on the primer/top coat. They are not relevent to the topic.
Q: 1. Can you send a few pictures of the areas we would be filling or repairing?

2. Does this filler need to be made out of a certain material?

3. Can we request sample parts - small areas to work on during our research phase?

4. Can you supply the data on what primer/top coat will be used?
A: 1. I have no pictures of the areas that need to be filled. The materials being looked at are plies of nickel coated carbon fibers in epoxy resins, mats of short nickel coated fibers in epoxy resins and chopped nickel coated fibers in thermoplastic resins. The areas to be filled or repaired are not as important as the replacing of nickel coating on the carbon fiber. I have posted to SITIS two pictures of a coated fiber and a coated carbon fiber tow.

2. A coated carbon fiber is required for the composite plies, and mat. The fastener filler has been qualified for chopped nickel coated carbon fiber and anything other than carbon fiber would require additional qualification that was not planned for this program. That said, other materials will be considered.

3. No sample parts are available.

4. No. I have no data on the primer/top coat. They are not relevent to the topic.

Record: of