Prev Next. Although carbon fiber has been around for more than years, it has only been through manufacturing process improvements in the last half century or so that its excellent strength-to-weight and stiffness-to-weight ratios have been achieved.
These modern advances, coupled with decreases in manufacturing costs over the last couple of decades, are what have made carbon fiber become such a popular material for design engineers to use in some of today's greatest technological advances. In , Thomas Edison used cellulose-based carbon fiber filaments in some of the first light bulbs to be heated by electricity. Their high heat tolerance made them ideal electrical conductors.
These filaments were made of cotton or bamboo, as opposed to today's petroleum-based raw materials, and then baked at high temperatures to cause carbonization to take place. This baking method, called "pyrolysis", is still used today. Pyrolysis is the process of thermally decomposing organic matter by heating it at high temperatures in an inert atmosphere.
When tungsten became the light bulb filament of choice in the early s, carbon fiber was rendered obsolete for the next 50 years or so. In , at the Union Carbide Parma Technical Center in Cleveland, OH, Roger Bacon accidentally produced the first petroleum-based carbon fibers when he tried to measure the triple point of carbon by heating strands of rayon in argon.
He noticed filaments growing on the negative electrode of the arc furnace, and he noted this observation in his findings. By the end of World War II, Union Carbide was researching an alternative for tungsten wire in vacuum tubes, by carbonzing rayon, another cellulose based structure. The end of war resulted in the termination of this project, however the interest of the commercial sector in carbon fiber had been piqued. In , Barnebey-Cheney Company started to manufacture carbon fiber mats from rayon and cotton.
Subsequently, Union Carbide made a carbonized rayon cloth in the next year and offered it to US Airforce as an alternative to fiberglass based aircraft heat shields. While these discoveries and developments were impactful to a certain degree, they had poor mechanical characteristics which rendered them unsuitable for large scale use and manufacturing.
The age of full blown carbon fiber discoveries and applications was still ahead. The modern age of carbon fibers commenced with the development of large scale university-like laboratories in the late s, which gave young researchers a relatively higher degree of autonomy to work on the areas of their interests.
They were embedded like straws in brick. They were up to an inch long, and they had amazing properties. They were long filaments of perfect graphite. In , Bacon finally published a paper in the Journal of Applied Physics, making it a milestone in the research of carbon fibers and carbon nanotubes.
Subsequently, in , Sumio Ijimia published a paper which reported a method for the development of carbon nanotubes and scrolls. The research in the next decades would be dedicated to efficient and affordable methods of production. Carbon fiber -- sometimes known as graphite fiber -- is a strong, stiff, lightweight material that has the potential to replace steel and is popularly used in specialized, high-performance products like aircrafts, racecars and sporting equipment. Carbon fiber was first invented near Cleveland, Ohio, in Current methods for manufacturing carbon fiber tend to be slow and energy intensive, making it costly for use in mass-produced applications.
Lowering the cost of carbon fibers make it a viable solution for vehicles and a wide variety of clean energy applications. The 42,square foot facility features a foot-long processing line that is capable of producing up to 25 tons of carbon fiber a year -- that is enough carbon fiber to cover the length of almost , football fields. The most common carbon fiber precursor -- the raw material used to make carbon fibers -- is polyacrylonitrile or PAN , accounting for more than 90 percent of all carbon fiber production.
The lamps were composed of two carbon rods connected to a current source and separated by a short distance. National Carbon got its start by producing carbon electrodes for streetlamps in downtown Cleveland. In , Thomas Edison invented the first incandescent light bulb, which uses electricity to heat a thin strip of material, called a filament, until it glows.
He may also have created the first commercial carbon fiber. To make his early filaments, Edison formed cotton threads or bamboo slivers into the proper size and shape and then baked them at high temperatures. Cotton and bamboo consist mostly of cellulose, a natural linear polymer made of repeating units of glucose.
Tungsten wire soon displaced these carbon filaments, but they were still used on U. Navy ships as late as because they withstood ship vibrations better than tungsten. Near the end of World War II, Union Carbide began investigating a replacement for tungsten wire in vacuum tubes by carbonizing rayon, another cellulose-based polymer like cotton that became popular in clothing.
Barnebey-Cheney Company, in , briefly manufactured carbon fiber mats and tows rope-like threads without the twists from rayon and cotton. These were used as high temperature insulation and filters for corrosive compounds.
A year later, Union Carbide developed a carbonized rayon cloth and submitted it to the U. Air Force as a replacement for fiberglass in rocket nozzle exit cones and re-entry heat shields. While finding a certain degree of success in their respective niches, all of these early carbon fiber materials had poor mechanical properties, making them unsuitable for structural use. It took a chance discovery to set the age of high performance carbon fibers in motion.
The modern era of carbon fibers began in , when Union Carbide opened its Parma Technical Center just outside Cleveland. They gathered young, bright scientists from a variety of backgrounds and let them loose on their favorite projects, giving them an extraordinary degree of autonomy. With a freshly minted Ph. Small amounts of vaporized carbon would travel across the arc and then deposit as liquid.
As Bacon decreased the pressure in the arc, he noticed that the carbon would go straight from the vapor phase to the solid phase, forming a stalagmite-like deposit on the lower electrode. They were up to an inch long, and they had amazing properties. They were long filaments of perfect graphite. The year was , and Bacon had demonstrated the first high performance carbon fibers.
In fibrous forms, carbon and graphite are the strongest and stiffest materials for their weight that have ever been produced. Carbon fibers are polymers of graphite, a pure form of carbon where the atoms are arranged in big sheets of hexagonal rings that look like chicken wire. The paper has since become a milestone, partially because some have claimed that Bacon may have been the first person to produce carbon nanotubes—hollow cylinders of graphite with diameters on the order of single molecules.
Their incredible properties have made nanotubes one of the hottest areas of research in recent years, promising to revolutionize just about every area of science. Sumio Iijima published a paper in that is often regarded as the first discovery of carbon nanotubes; it reported on a method that produced both tubes and scrolls. By producing his high strength and high modulus whiskers, Bacon had demonstrated experimentally something that theoreticians had proposed long ago.
But the fibers were still just a laboratory phenomenon, not a practical development.
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