What makes carbon fiber composites unique and why it is so costly?

Carbon fibers are a very unique and preeminent material in the manufacturing industry. Be it automobiles, aerospace, chemical industry or medical equipment, CFRP is massively used in the manufacturing of components requires for the mentioned industries due to their unique characteristics that make them a prominent raw material. The two main applications of carbon fibers parts and carbon fiber sheets are in specialized technology, which includes aerospace and nuclear engineering, and in general engineering and transportation, which includes engineering components such as gears, fan blades and automobile bodies. 

Usage of carbon fiber by itself is not the rule. Commonly, customers apply carbon fibers for fortification and/or functionality of composite materials, made with resin, ceramic or metal as a matrix. Carbon fibers are extensively applied to a large variety of applications with supreme mechanical characteristics (specific tensile strength, specific modulus) and other characteristics due to carbon fiber composites matter (low density, low coefficient of thermal expansion, heat resistance, chemical stability, etc.). These characteristics make the CF so unique and distinctive, which is the reason why almost all the manufacturing industries are into it.

What makes carbon fiber composites so unique? 

The performance characterizing attributes, and the special features of carbon fiber defines its uniqueness. These features include:

1. Carbon Fiber Reinforced Plastics (CFRP) is superior to steel or glass fiber reinforced plastics (GFRP) in their specific tensile strength and specific elastic modulus (specific rigidity). CFRP is “strong and light in weight” in its mechanical performance. Moreover, the fatigue resistance of carbon fiber composites surpasses that of other structural materials.
2. Carbon fiber parts have a low heat expansion ratio and high dimensional stability and sustains those excellent mechanical performances even under a high-temperature region.
3. Carbon Fibers have high electric conductivity (volumetric impedance) and at the same time have excellent EMI shielding properties. This successfully brings CFRP to the field of EMI shielding.
4. As Carbon Fibers have magnificent X-ray radiolucency in addition to being light in weight and rigid, carbon fiber composites are highly welcomed in the field of medical equipment parts. CFRP contributes to attaining sharper and clearer photo images.

What value can these composites add?

The next generation of carbon fibre composites like prepreg composites could reduce passenger car weight by 50 percent and improve fuel efficiency by about 35 percent without compromising performance or safety; an advancement that would save more than $5,000 in fuel over the life of the car at today’s gasoline prices. In addition to its uses in the manufacturing of cars and trucks, advances in carbon fiber will help American manufacturers lower the cost and improve the performance of wind turbine blades and towers, electronics, energy storage components and power transmission lines.  

Moreover, in the 3D printing technology, the carbon fiber composites are adding value with their presence. This is a sophisticated technology used for several applications and does not require a large equipment setup. This technology can be used to print several objects in a short period. Continuous carbon fibers are used in 3D printing as if it offers high strength and rigidity compared to other metallic materials. The content and orientation of carbon fiber are controllable, which eases the optimization process. 3D printing using carbon fibers also allows for high accuracy in the manufacturing of parts for various end-use industries such as aerospace, automotive, and dental. This technology will revolutionize the carbon fiber manufacturing process and will offer significant opportunities for the market players. 

Why is it so expensive?

The starting material, a carbon-rich acrylic similar to the ones used in sweaters and carpets, is not that expensive at $3 a pound. But processing it from a solid into stings of carbon requires huge, energy-sucking machines to heat it for hours. Plus, there’s 50 per cent waste. After three heating cycles, at temps upwards of 1,000 degrees Celsius, the power bill is huge. And that’s just for the strands. Now each fiber must be woven into lattice sheets an equally exacting and costly step. Each strand needs to be pulling its weight to ensure even strength. Once the fibers are weaved into sheets a resin is added to set its final shape. Screw that up and you need to start all over. All in all, carbon fiber may start at $3 a pound, but by the time it reaches a bike frame manufacturer, it will cost closer to $20 per sqm for prepreg composites fabric. Add >1000 hours of development/implementation labor time, a few mistakes, lots of waste and your $4,000 carbon fiber bike frame doesn’t sound so expensive anymore. Furthermore, manufacturing and assembly machines aren’t the only technology cost factors to consider. New composite manufacturing software is coming out on the market. For example:

• Design simulation software to reduce the design cycle time
• Cost modelling software to analyze sources of lost efficiency
• Knowledge-based engineering products to lower labour costs

Software providers are also introducing products to help identify manufacturing risks upfront. This will reduce costly mistakes before they happen, further reducing cycle times and carbon fiber manufacturing costs.

Therefore, these factors drive the costs of carbon fiber composites / prepreg composites to such heights. The carbon fiber market, by application, is led by the composite segment, in terms of value and volume both. The growth is due to the wide-scale use of the composite form of carbon fiber in various industries such as aerospace & defence, automotive, and wind energy. The scalability and scope of carbon fiber manufacturing and carbon fiber machining are spread around the world especially in Europe which holds the largest market share of the carbon fiber market as there are a large number of offshore wind energy installations, especially in the UK and Germany. 

Though the manufacturers are focusing on producing low-cost carbon fibers, the mass production and commercialization would take time. In order, to compete with PAN fibers, the cost of carbon fibers must be brought down by mass production. The applications of carbon fiber are still restricted due to its high cost hence, justifying the uniqueness of its characteristics and the high price affiliated with the end product.