December 20, 2016

590 Views

Future Aircraft Composite Material : Graphene

Co-authored by : Maheswara Poothireddy

Current Aircraft Composite Materials

Before talking about the current composite materials, let me first explain what composite material means. A composite material is nothing but a union of two or more unrelated materials which combines to impart their best properties which a single constituent cannot give, or rather we should say that they form a team to give their best results together. It’s been quite some time since the implementation of fibre reinforced plastics in engineering structures transformed sports accessories, racing cars, helicopters and commercial aeroplanes. With the evolution of carbon and glass fibres in 1950’s, the aerospace industry started heading towards complete composite aircraft. Consequently, aircraft giants like Boeing and Airbus have started to incorporate composite materials in their aircraft parts to a large extent, like the Boeing 787 Dreamliner and the Airbus A350 XWB.

The Industry is moving from aluminium materials to carbon composite material in order to reduce weight, fuel consumption, and to increase safety and strength. And constant innovations are enhancing the benefits of carbon composites.

Future Composites

During our research, we came across a very interesting material named “Graphene”. Graphene came into the limelight in 2004 when Nobel laureates Konstantin Novoselov and Andre Geim introduced it to the world. This material exhibits quite a few amazing characteristics. To talk about a few, Graphene is 100 times stronger than the strongest steel with an atomic thickness of 0.345nm. Graphene also has the property to conduct heat and electricity and is almost transparent.

In the initial implementations, unexpectedly, Graphene has been used to create epoxy resins which will increase the electrical conductivity (with both holes and electrons as charge carriers) of carbon composite material substantially, which in turn, will be used for manufacturing aircraft fuselages. This application will eventually neutralize the current usage of copper based mesh to protect the aircraft from lightning strikes.

Lightning poses a great threat to an aircraft during the course of the flight. If lightning strikes it must be provided proper a grounding or earthing system, but the composite materials are incapable of this as they tend to be inert. Therefore, it is quite critical for the composites to become more conducti, which the graphene-based epoxy resins enable.

Apart from the above quality, with the usage of graphene, the weight of the aircraft can be reduced. Hence, the fuel consumption can be reduced drastically as well as the take-off and landing runway length can be reduced.

There are, however, some disadvantages of Graphene as well.

  • Earlier we talked about Graphene being electrically conductive, but actually, graphene is highly conductive. Graphene can conduct the electrons at a speed which is almost the same as the speed of light. It is almost 100 times faster than any other material. But practically we don’t need such high speed of electrons, therefore some impurities can be added to Graphene to bring down its conduction speed.
  • The biggest issue with graphene is that it exhibits toxic qualities which are quite harmful to humans.
  • The price of graphene is also quite high and depends on its quality. Graphene oxide in solution sells for 99 euros per 250 mL.

References