What are composite materials?

Composite materials (also referred to as composition materials, or simply composites) are materials formed by combining two or more materials with different properties to produce an end material with unique characteristics. These materials do not blend or dissolve together but remain distinct within the final composite structure. Composite materials can be made to be stronger, lighter or more durable than traditional materials due to properties they gain from combining their different components.

Most composites are made up of two materials - the matrix (or binder) surrounds a cluster of fibers or fragments of a stronger material (reinforcement). A common example of this structure is fiberglass, which was developed in the 1940’s to be the first modern composite and is still in widespread use. In fiberglass, fine fibers of glass, which are woven into a cloth of sorts, act as the reinforcement in a plastic or resin matrix.

composite crossection image

While composite materials are not a new concept (for example, mud bricks, made from dried mud embedded with straw pieces, have been around for thousands of years), recent technologies have brought many new and exciting composites to existence. By careful selection of matrix and reinforcement (as well as the best manufacturing process to bring them together) it is possible to create significantly superior materials, with tailored properties for specific needs. Typical composite materials include composite building materials like cement and concrete, different metal composites, plastic composites and ceramic composites.

How are composite materials made?

The three main factors that help mold the end composite material are the matrix, reinforcement and manufacturing process. As matrix, many composites use resins, which are thermosetting or thermosoftening plastics (hence the name ‘reinforced plastics’ often given to them). These are polymers that hold the reinforcement together and help determine the physical properties of the end composite.

layers inside a composite image



Thermosetting plastics begin as liquid but then harden with heat. They do not return to liquid state and so they are durable, even in extreme exposure to chemicals and wear. Thermosoftening plastics are hard at low temperatures and but soften with heat. They are less commonly used but possess interesting advantages like long shelf life of raw material and capacity for recycling. There are other matrix materials such as ceramics, carbon and metals that are used for specific purposes.

Reinforcement materials grow more varied with time and technology, but the most commonly used ones are still glass fibers. Advanced composites tend to favor carbon fibers as reinforcement, which are much stronger than glass fibers, but are also more expensive. Carbon fiber composites are strong and light, and are used in aircraft structures and sports gear (golf clubs and various rackets). They are also increasingly used to replace metals that replace human bones. Some polymers make good reinforcement materials, and help make composites that are strong and light.

The manufacturing process usually involves a mould, in which the reinforcement is first placed and then the semi-liquid matrix is sprayed or poured in to form the object. Moulding processes are traditionally done by hand, though machine processing is becoming more common. One of the new methods is called ‘pultrusion’ and is ideal for making products that are straight and have a constant cross section, like different kinds of beams. Products that of thin or complex shape (like curved panels) are built up by applying sheets of woven fiber reinforcement, saturated with matrix material, over a mould. Advanced composites (like those which are used in aircraft) are usually made from a honeycomb of plastic held between two sheets of carbon-fiber reinforced composite material, which results in high strength, low weight and bending stiffness.

Where can composites be found?

Composite materials have many obvious advantages, as they can be made to be lightweight, strong, corrosion and heat resistant, flexible, transparent and more according to specific needs. Composites are already used in many industries, like boats, aerospace, sports equipment (golf shafts, tennis rackets, surfboards, hockey sticks and more), Automotive components, wind turbine blades, body armour, building materials, bridges, medical utilities and others. Composite materials’ merits and potential assures ample research in the field which is hoped to bring future developments and implementations in additional markets.

Modern aviation is a specific example of an industry with complex needs and requirements, which benefits greatly from composite materials’ advantages. This industry raises demands of light and strong materials, that are also durable to heat and corrosion. It is no surprise, then, that many aircraft have wing and tail sections, as well as propellers and rotor blades made of composites, along with much of the internal structure.

What is graphene?

Graphene is a two-dimensional matrix of carbon atoms, arranged in a honeycomb lattice. A single square-meter sheet of graphene would weigh just 0.0077 grams but could support up to four kilograms. That means it is thin and lightweight but also incredibly strong. It also has a large surface area, great heat and electricity conductivity and a variety of additional incredible traits. This is probably why scientists and researchers call it “a miracle material” and predict it will revolutionize just about every industry known to man.

Graphene and composite materials

As was stated before, graphene has a myriad of unprecedented attributes, any number of which could potentially be used to make extraordinary composites. The presence of graphene can enhance the conductivity and strength of bulk materials and help create composites with superior qualities. Graphene can also be added to metals, polymers and ceramics to create composites that are conductive and resistant to heat and pressure.

graphene and tin layered composite image

Graphene composites have many potential applications, with much research going on to create unique and innovative materials. The applications seem endless, as one graphene-polymer proves to be light, flexible and an excellent electrical conductor, while another dioxide-graphene composite was found to be of interesting photocatalytic efficiencies, with many other possible coupling of materials to someday make all kinds of composites. The potential of graphene composites includes medical implants, engineering materials for aerospace and renewables and much more.

Further reading

Latest Graphene Composite news

China-US team uses graphene composite separator to achieve robust Li-S batteries

A team of researchers from The University of Texas at Austin and University of California in the US, along with teams from the University of Electronic Science and Technology, Hunan University and Soochow University in China, report the design of a negatively charged graphene composite separator for the effective suppression of the polysulfide shuttling effect in Li-sulfur batteries. The negatively charged 3D porous structure effectively inhibits the translocation of negatively charged polysulfide ions to enable highly robust Li-S batteries.

China-US team uses graphene composite separator to suppress polysulfide shuttling in Li-S batteries image

In their paper, the researchers show that by using a reduced graphene oxide (rGO)/sodium lignosulfonate (SL) composite on the standard polypropylene (PP) separator (rGO@SL/PP), they demonstrated a highly robust Li-S battery with a capacity retention of 74% over 1,000 cycles.

Graphene-skinned aircraft is given first airing

Scientists have unveiled Juno: a three-and-a-half-meter wide graphene-skinned aircraft that was given it’s first public airing on the North West Aerospace Alliance (NWAA) stand as part of the ‘Futures Day’ at Farnborough Air Show. Haydale has supplied the enhanced prepreg material used to make the Juno.

Juno graphene-skinned aircraft image

The unmanned vehicle was developed in a partnership between Haydale, an aerospace engineering team from the University of Central Lancashire, the Sheffield Advanced Manufacturing Research Center and the University of Manchester's National Graphene Institute. The partners have been working on the project to get the super lightweight plane ready for action. Billy Beggs, UCLan’s Engineering Innovation Manager, said: “The industry reaction to Juno at Farnborough was superb with many positive comments about the work we’re doing". “Having Juno at one the world’s biggest air shows demonstrates the great strides we’re making in leading a program to accelerate the uptake of graphene and other nano-materials into industry". He added: “The program supports the objectives of the UK Industrial Strategy and the University’s Engineering Innovation Centre (EIC) to increase industry relevant research and applications linked to key local specialisms. Given that Lancashire represents the fourth largest aerospace cluster in the world, there is perhaps no better place to be developing next generation technologies for the UK aerospace industry.”

The Graphene Catalog - find your graphene material here

Talga Resources reports breakthrough on its graphene-infused concrete project

Australia-based advanced materials company Talga Resources has reported high levels of electrical conductivity in concrete by using an additive developed from the Company’s graphene-graphite research and development laboratory in the UK.

Talga reports advancements of graphene-enhanced concrete project image(L) Talga concrete sample after melting 5cm depth of ice from 9v power. (R) Conceptual underfloor heating/road application.

The reported breakthrough offers substantial potential in existing and emerging industrial applications, particularly as concrete is the world’s largest construction material by volume. Talga shared information gathered from tests that show that the graphene-enhanced concrete is highly electrically conductive - attaining 0.05 ohm.cm volume resistivity.

First Graphene to work with newGen on graphene-enhanced products for the mining services industry

First Graphene logo imageFirst Graphene has signed a Memorandum of Understanding with newGen Group (WA-based mining industry supplier, providing liners for the leading iron ore producers, including BHP, RIO and Fortescue) for the development of graphene-enhanced products (primarily polyurethane liners) for the mining services industry.

Having established its graphene production facility at Henderson, FGR’s primary focus now is working with a number of manufacturers in a range of industries to demonstrate the benefits that graphene can offer to their product ranges. The newly entered agreement involves adding graphene to polyurethane liners and ground engaging tools used in the mining industry. The Project Equipment used in the mining industry is frequently modified with the installation of polyurethane liners to protect them from excessive abrasion, and these liners need to be replaced at regular intervals.

First Graphene and Flinders University form a new company to commercialize VFD technology

First Graphene logo imageFirst Graphene is collaborating with Flinders University to launch 2D Fluidics - a company that will aim to commercialize the Vortex Fluidic Device (VFD). 2D Fluidics is 50% owned by FGR and 50% by Flinders University’s newly named Flinders Institute for NanoScale Science and Technology.

The VFD was invented by the Flinders Institute for NanoScale Science and Technology’s Professor Colin Raston and enables new approaches to producing a wide range of materials such as graphene and sliced carbon nanotubes. The key intellectual property used by 2D Fluidics comprises two patents around the production of carbon nanomaterials, assigned by Flinders University.

XFNANO: Graphene and graphene-like materials since 2009XFNANO: Graphene and graphene-like materials since 2009