Article last updated on: Jan 29, 2019

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

The latest graphene composite news:

Graphmatech and Wematter partner to develop graphene-enhanced materials for SLS 3D printing

Swedish graphene-solutions provider Graphmatech has partnered with 3D printer manufacturer Wematter to enhance polymer powders with graphene, to make them electrically- and thermally conductive, improve processibility, and more.

Together, the two startups will develop an electrically conductive powder, tailored for Gravity – the SLS 3D printer by Wematter. The high-performance powder will enable Telecommunications, Aerospace and Automotive manufacturers to print parts with improved or maintained mechanical properties whilst achieving electrostatic dissipative (ESD), shielding, or even lower resistivity, performance.

On SP Nano’s cutting-edge graphene and CNT dispersion technology

This is a sponsored post by SP Nano

Israel-based SP Nano developed a unique dispersion technology based on a genetically engineered exceptionally stable protein that is highly suitable for carbon nanoparticles (CNPs) dispersion, including graphene, CNTs and carbon black.

Following years of intensive R&D, SP Nano is now offering its dispersions to application developers. This is the first time that carbon nanomaterials can “truly” be dispersed and achieve cutting-edge performance across a wide range of applications.

SP Nano’s dispersions are now being applied to a wide range of applications, such as

  • Coatings (textiles, surfaces, powders, etc.)
  • Dispersions in matrices (resins, polymers, etc.)
  • Liquid formulations (coolants, inks, slurries, etc.)

Viritech launches graphene-enhanced "hypercar"

Last year's announcement about a British engineering company called Viritech that is working on an ambitious hydrogen-powered hypercar was recently followed by an update on that same company, that unveiled its 745kW hydrogen-powered hypercar, styled by Italian car design specialist Pininfarina.

Graphene-enhanced Apricale hypercar image

The Apricale, which produces zero emissions, made its debut at Goodwood’s Festival of Speed. It was said that the Apricale uses ‘graphene-reinforced hydrogen pressure vessels’, which was explained to mean that the hydrogen storage tanks form a structural element of the chassis. This reduces weight and cost, while simplifying the structure.

Researchers create improved wigs using graphene oxide

Researchers from China's Donghua University have developed a new way to make wigs more durable and longer lasting - using graphene oxide.

Hairpieces can be made of real human strands or synthetic materials, but either way, washing, UV exposure from the sun and repeated styling can cause these products to become dry and brittle. To extend the life of wigs, researchers have spray-coated a layer of graphene oxide on them, whereas other teams have immersed wigs in a keratin/halloysite nanocomposite. Since it's difficult to cover an entire hairpiece with these methods, the team wanted to see if a nanocomposite applied with a tried-and-true approach for coating surfaces with ultrathin films - known as the Langmuir-Blodgett (LB) technique - could improve coverage and increase durability.

Gerdau Graphene launches graphene-enhanced plastics

Gerdau Graphene has announced that it has created next-generation graphene-enhanced plastics at a Brazilian government-funded advanced materials center in São Paulo.

Gerdau Graphene Develops Ultra-Strong Graphene-Enhanced Plastics image

The new graphene-enhanced polymeric resin masterbatches formulas for polyethylene (PP) and polypropylene (PE) were created in partnership with Brazil’s EMBRAPII SENAI/SP Advanced Materials Unit, and are being piloted in a series of industrial applications within Gerdau’s factories. The new thermoplastic products created using these formulas will be stronger and offer greater overall performance while costing less to manufacture and producing significantly less waste across the value chain. The first commercial deliveries are expected in June.