Carbon Fiber: The Material Of Choice For Funny Car Bodies

Carbon fiber can refer to carbon filament thread, or to felt or woven cloth made from those carbon filaments. By extension, it is also used informally to mean any composite material made with carbon filament; for more on that application, see graphite-reinforced plastic.

Synthesis

Each carbon filament is made out of long, thin sheets of carbon similar to graphite. A common method of making carbon filaments is the oxidation and thermal pyrolysis of polyacrylonitrile (PAN), a polymer used in the creation of many synthetic materials. Like all polymers, polyacrylonitrile molecules are long chains, which are aligned in the process of drawing fibers. When heated in the correct fashion, these chains bond side-to-side, forming narrow graphene sheets which eventually merge to form a single, jelly roll-shaped filament. The result is usually 93-95% carbon. Lower-quality fiber can be manufactured using pitch or rayon as the precursor instead of PAN. The carbon can become further enhanced, as high modulus, or high strength carbon, by heat treatment processes. Carbon heated in the range of 1500-2000°C (carburizing) exhibits the highest tensile strength (820,000 Psi or 5,650 N/mm²), while carbon fiber heated from 2500-3000°C (graphitizing) exhibits a higher modulus of elasticity (77,000,000 psi or 531 kN/mm²).

Textile

These filaments are stranded into a thread. Carbon fiber thread is rated by the number of filaments per thread, in thousands. For example, 3K (3,000 filament) carbon fiber is 3 times as strong as 1K carbon fiber, but is also 3 times as heavy. This thread can then be used to weave a carbon fiber cloth. The appearance of this cloth generally depends on the size of thread and the weave chosen. Carbon fiber is naturally a glossy black but recently colored carbon fiber has become available.

Uses

Carbon fiber is most notably used to reinforce composite materials, particularly the class of materials known as graphite reinforced plastic. This class of materials is used in high-performance vehicles, sporting equipment, and other demanding mechanical applications; a more thorough discussion of these uses, including composite lay-up techniques, can be found in the carbon fiber composite article.

Non-polymer materials can also be used as the matrix for carbon fibers. Due to the formation of metal carbides (i.e., water-soluble AlC) and corrosion considerations, carbon has seen limited success in metal matrix composite applications. Reinforced carbon-carbon (RCC) consists of carbon fiber-reinforced graphite, and is used structurally in high-temperature applications, such as the nose cone and leading edges of the space shuttle.

The fiber also finds use in filtration of high-temperature gases, as an electrode with high surface area and impeccable corrosion resistance, and as an anti-static component in high-performance clothing.

Some string instruments, such as violins and cellos, use carbon fiber reinforced composite bows. This is an alternative to the more common wooden bows.

Many high-end frames for road bikes and mountain bikes are made of carbon fiber reinforced composite. Also, many road bikes made of aluminum have carbon fiber reinforced composite seat posts, handlebars and forks for reduced weight.

Future Directions

Carbon nanotubes are currently being investigated as possible improvements on the traditional carbon fiber material. While the nanotechnology field isn't advanced enough to create long-enough fibers made entirely of carbon nanotubes, research has shown that even as little as 5% (by weight) carbon nanotube constituents within the carbon fibers will dramatically improve properties. It has been reported that tensile strength increased by 90%, modulus increased by 150% and electrical conductivity increased by 340%. This was in a pitch composite fiber with 5% (by weight) loading of purified single walled nanotubes (as compared to the corresponding values in unmodified isotropic pitch fibers). Further research is still needed to resolve issues such as nanotube dispersion and alignment, as well as interfacial bonding; however, this approach holds great promise for improving both the mechanical and electrical properties of carbon fiber composites

Best Cheap Drag Car (Chevy Vega)

The Chevrolet Vega was a compact coupe and station wagon sold from 1971 through 1977 as a replacement for the ill-fated Chevrolet Corvair. It was based on the GM H platform and was followed by the 1975-1980 Chevrolet Monza. The similar Pontiac Astre was available in Canada from 1973 through 1977, and in the U.S. from 1975 through 1977. The Vega 2300 was Motor Trend's Car of the Year for 1971.

When the Vega was introduced, Detroit's Big Three (GM, Ford, Chrysler), along with American Motors, were entering the compact car market to compete with the Volkswagen Beetle along with Japanese imports from Toyota and Datsun.

All standard Vegas and Astres were equipped with a 2.3 L "2300" SOHC I4. The standard engine used either a single-barrel carburetor which produced about 70 hp, or a 2-barrel option which boosted output to 85 hp. These motors had cast iron heads with aluminum-silicon cylinder blocks without iron sleeves; a wear surface for the piston was created by etching the cylinder bore with an electrochemical process. Early models overheated due to poor cooling channel design. Vega engines (except for the Cosworth) typically burned oil not due to cylinder wear (which was the rumor) but instead due to poorly designed valve stem seals. The exception was the limited-edition 1975-76 Cosworth Vega, which used a fuel-injected DOHC 2.0 Litre version of the engine built by Cosworth Engineering in England.

The Vega was the first automobile that GM produced that offered front wheel disc brakes as standard equipment. It was also the first car that GM produced that used extensive use of robotic welding equipment.

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