Session: Research Posters

Paper Number: 120221

120221 - Lightweight Conductive Composite Network for Aircraft Lightning Strike Protection 

During the last few decades, application of carbon fiber reinforced polymer (CFRP) composites in aircraft structural elements have been steadily increased. CFRP composites are lightweight, corrosion resistant and possesses better mechanical properties, fatigue resistance and lower thermal expansion. However, they are nearly 2000 times less electrically conductive than previously used aluminum alloys. Which makes them prone to serious structural damage in the event of a lightning strike. To protect the aircraft, the outer surface is covered with conductive metallic jacket which consequently reduces the weight advantage of the CFRP composite. There is a dire need for a lightweight alternative for lightning strike protection which will be just as effective. In this study, a lightweight composite conductive network was developed by controlled formation of copper thin film over electrospun carbon nanofiber. When it comes to electrical properties, copper and carbon shows complementary characteristics. Copper is highly conductive and shows low contact resistance but heavy and moderate in current carrying capacity. Whereas carbon is lightweight and possesses high current carrying capacity, but it is moderately conductive and shows very high contact resistance. Mainly due to contact resistance, carbon allotropes show much lower electrical conductivity in macro-scale, even though individually graphene and carbon nanotube show exceptionally high electrical conductivity. By coating the carbon with copper, carbon-carbon contact was replaced by copper-copper contact, hence reducing the high contact resistance. Copper coating was thin, mostly less than 100 nm in thickness, so it kept the weight gain to a minimum. Copper on the surface creates a faster gateway for electrical current as it possesses higher conductivity, on the other hand, in case of a high current flow, higher current carrying capacity of carbon prevents material failure. Electrospun carbon nanofiber was fabricated from polyacrylonitrile. Polyacrylonitrile (PAN) and N,N-Dimethylformamide (DMF) solution was electrospun into a nanofiber mat, followed by 6 hours of stabilization in the presence of air at 280 °C and 1 hour of carbonization in Nitrogen environment at 900 °C. Resulted electrospun carbon nanofiber mat was first sensitized using tin chloride solution followed by metallization using palladium chloride solution. The mat was then coated with copper using electroless deposition technique. Morphological studies were carried out with scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDX). Sheet resistance of the filler and the composite was measured using a four point probe electrical conductivity measurement instrument.  Preliminary result shows significant improvement of sheet resistance in the resultant material.

Presenting Author: Mohammad Uddin NC A&T State University

Presenting Author Biography: Mohammad Uddin is a PhD candidate in Nanoengineering at North Carolina A&T State University. He completed his MS in Materials Science and Engineering from Tuskegee University. Earlier he did his BS in Mechanical Engineering from Bangladesh University of Engineering and Technology (BUET). His research interest includes advanced material development, polymer composite, nanocomposite, nanowelding, high temperature polymer and composite repair.

Authors:

Mohammad Uddin NC A&T State University
Israt Jahan North Carolina A&T State University
Ram Mohan North Carolina A&T State University
Ajit Kelkar North Carolina A&T State University