Learn About Carbon Fibre

If you’re a fan of motorsports or other extreme sports then you likely already know a fair bit about carbon fibre; however, you may not know about the details, in terms of how it’s made, and about the different types of carbon fibre that are available. If you want to learn more then please read on.

Background

Carbon fibre, or carbon fibre reinforced polymer (CFRP), is a type of material that is used in extreme applications where high-strength and lightweight properties are required. It is used in a variety of industries such as racing cars, motorcycles, high-end bicycles, protective equipment, aircraft, boats, and even spacecraft. It is used to make products such as wheels, bodywork, propellers, frames/chassis’, wings, helmets, handlebars etc. Carbon fibre is far stronger than aluminium and yet it is much lighter. It offers similar levels of strength to that of solid steel yet it weighs only around one fifth of the weight. Carbon fibre is however, far more expensive to produce than steel or aluminium so it is typically only used for high-end luxury goods or in applications where its material properties are absolutely vital. This is why you do not typically see things like furniture, buildings or everyday road cars which are made from carbon fibre. You will see carbon fibre used to construct high-end cars such as the Lamborghini Aventador or for modern aircraft such as the Boeing 787 Dreamliner.

Production Process

The most common form of carbon fibre that you will see is weaved carbon; however, other types such as unidirectional and forged carbon also exist. Most carbon fibre starts life as propylene and ammonia gas. These two compounds are reacted together to create Polyacrylonitrile or PAN for short. The PAN is then mixed with other reactive ingredients to help form it into long fibres. These fibres then undergo further chemical treatment to stabilise them before they are superheated to carbonise and oxidised the fibres. At this point you now have very thin, flexible strands of carbon filament, which are much thinner than the width of a human hair. These thin fibres are then wound together onto a spool to create a thicker strand called a tow. Different grades of tow are available such as 1K, 3K, 6K, and 12K. The number and the letter K simply refers to how many thousands of individual strands of carbon filament make up each strand of tow. 3K is probably the most common type of carbon fibre in which the tow is made from approximately three thousand individual strands of carbon filament.

Weaved Carbon Fibre

To make weaved carbon fibre, multiple spools of tow are woven together to create a fabric, or they can be bonded together with a special resin to make a unidirectional carbon fibre fabric. The most common types of weaved carbon fibre are plain weave and 2x2 twill. Plain weave is when the tows are woven together in a simple, alternating, over and under method which creates a chequered pattern. Twill weave fabric is when the spools of tow are woven together by threading them over and under every second strand of tow rather than over and under every single one. This makes the carbon a bit easier to mould into shape later on. Twill weaving carbon fibre creates a kind of striped pattern, where each individual segment appears rectangular rather than square.

Once the carbon tows are woven together into a flexible fabric, the carbon fibre fabric is then cut to size, coated in a special resin and then placed into a mould, which is a precisely shaped negative of the particular component to be made. The carbon fibre is then vacuum sealed in a plastic bag to remove any air bubbles and then placed into an industrial oven called an autoclave. The autoclave applies heat and pressure to set the resin and cure the carbon fibre, creating an extremely strong and rigid structure. Once cooled, the surface of the carbon fibre can then be treated and polished to create a gloss or matte finish, or it can just be painted over.

Forged Carbon Fibre

Forged carbon fibre is a much less widely used type of carbon which was invented relatively recently by the Lamborghini automobile company in 2008. It is made by chopping carbon tow into small pieces, or by taking small pieces of a unidirectional carbon fabric, and mixing them together with a resin to create a sort of carbon paste. This paste is then poured into a mould and pressed into shape using extreme pressure which is applied by a hydraulic press. This pushes out any air bubbles and heats up the carbon, curing it, and sets the resin which makes the component extremely strong and rigid. Once cooled, the surface can then be treated in the same way as weaved carbon.

CarbonShield Products

We offer all of our carbon fibre products in both 3K twill-weave and forged carbon versions. Both types of carbon fibre are extremely strong and lightweight but they each provide a different aesthetic. The 3K twill-weave carbon fibre offers a beautifully structured pattern, whilst the forged carbon offers a much more raw and natural look. Each and every piece of forged carbon fibre possesses a completely unique pattern, whilst the twill weave carbon offers a much more uniform design. Please feel free to take a look at our product store so you can see perfect examples of both forged and twill-weave carbon fibre.