Composites in Industry
What is Carbon Fibre?
Carbon fibre are fibres about 5–10 micrometres in diameter and composed mostly of carbon atoms.
The raw material used to make carbon fibre is called the precursor. About 90% of the carbon fibres produced are made from polyacrylonitrile (PAN). The remaining 10% are made from rayon or petroleum pitch. All of these materials are organic polymers, characterised by long strings of molecules bound together by carbon atoms. The exact composition of each precursor varies from one company to another and is generally considered a trade secret.
During the manufacturing process, a variety of gasses and liquids are used. Some of these materials are designed to react with the fibre to achieve a specific effect. Other materials are designed not to react or to prevent certain reactions with the fibre. As with the precursors, the exact compositions of many of these process materials are considered trade secrets.
The process for making carbon fibres is part chemical and part mechanical. The precursor is drawn into long strands or fibres and then heated to a very high temperature without allowing it to come in contact with oxygen. Without oxygen, the fibre cannot burn. Instead, the high temperature causes the atoms in the fibre to vibrate violently until most of the non-carbon atoms are expelled. This process is called carbonisation and leaves a fibre composed of long, tightly inter-locked chains of carbon atoms with only a few non-carbon atoms remaining.
Carbon fibres are usually combined with other materials to form a composite. When combined with a plastic resin, pressed and moulded it forms carbon-fibre-reinforced polymer (often referred to as carbon fibre) which has a very high strength-to-weight ratio, and is extremely rigid.
Carbon Technology have been instrumental in gaining the acceptance of epoxy carbon chambered doctor blades into the printing industry where the environmentally driven shift from solvent based to water based inks has presented major corrosion problems particularly with aluminium components.
The application of carbon fibre can deliver weight savings that transform previously heavy and cumbersome equipment into lighter and more portable equipment, which for the service and maintenance industry can save time and man power reducing down time and improved service to the customer. Increasingly stringent manual handling regulations present numerous problems for industry and increased down time and expense. Correct design of components in carbon fibre can often reduce the weight sufficiently to avoid the need for lifting equipment.