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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.

applications of composites image

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

Graphene-based electrostatic speaker developed by China-based company

Dec 25, 2016

Wuxi JCNO Materials, a company located in the Wuxi Graphene Industry Zone in China, has created a graphene-based electrostatic speaker. The speakers are reportedly constructed using graphene resin composite materials, able to produce medium and low bass sounds that conventional metal resin compounds cannot reach. The graphene speaker is also said to be simpler, longer-lasting and cheaper to produce than traditional technology.

Electrostatic speakers sound by vibrating the diaphragm before and after with the action of electrostatic force. It can capture the extremely small changes in the music signal to fully show the nuances of the music. This kind of speaker has already been used in applications like cars, theaters and exhibitions.

Versarien enters agreement with Fern Plastic Products to manufacture graphene-enhanced injection moulded products

Dec 20, 2016

Versarien announced an agreement with Fern Plastic Products to manufacture injection moulded products using graphene-enhanced polyaryletherketone (PAEK) materials. The agreement with Fern Plastics follows the agreement with Scafell Organics announced earlier this month.

The plan is for Versarien to utilize Fern Plastics' manufacturing facilities and expertise to produce injection moulded products using graphene-enhanced PAEK materials produced through Versarien's collaboration with Scafell.

Graphene Batteries Market Report

Versarien enters agreement with Scalfell Organics to develop graphene-enhanced PAEK materials

Dec 18, 2016

Versarien logo imageVersarien, the advanced materials group, has signed an agreement with polymer chemical producer Scafell Organics to develop graphene-enhanced polyaryletherketone materials (PAEKs). These materials are a family of semi-crystalline thermoplastics with high-temperature stability and high mechanical strength, used in the automotive and aerospace industries.

Versarien reportedly plans to utilize Scafell’s facilities and production expertise to produce graphene enhanced PAEK materials using Versarien supplied graphene nano platelets. It is hoped that these graphene enhanced materials will be available for sale by Versarien through its sales team as well as Scafell’s customers.

CalBattery announces scaling-up production of its high capacity anode material

Dec 13, 2016

CalBattery logoCalBattery, the U.S-based developer of a Silicon-Graphene (SiGr) composite anode material for li-ion batteries, recently announced that it has successfully scaled-up its new fluidized bed chemical vapor deposition process and is producing commercial quality and quantities of its breakthrough high capacity silicon composite anode material for use in li-ion batteries.

Over the past 5 years CalBattery’s team has worked with over thirty engineering groups to develop, build, and optimize a new type of fluidized bed chemical vapor deposition reactor capable of producing novel industry leading silicon composite lithium battery anode materials that can be specially engineered to incorporate between 10% -50% silicon with limited swelling and good cycle life compared to other LIB silicon anode materials used today.

Graphene-enhanced street lighting fixtures are being deployed in China

Dec 08, 2016

Reports out of China state that graphene-based road lighting fixtures are being installed in 28 streets in Beijing, which are said to be up to 30% more energy efficient than current fixtures. These graphene lamps can reportedly reach 140 lumens per watt, which means the new lamps can be much brighter than currently used ones, that produce 110 lumens per watt.

The fixtures' exteriors are made of black and grey composite materials and most of the heat-conducting adhesives and chips inside are said to be produced with graphene. The Chinese official PR mentioned a company called MS Technology but its exact role is not clear. It is said to be "a company focusing on heat dispersing materials research and the firm that first invented graphene lamps that were put into mass production".