Carbon fiber | In detail
Carbon fiber is a revolutionary material that has transformed numerous industries and applications, ranging from aerospace and automotive engineering to sports equipment and even medical devices. Composed of thin, exceptionally strong carbon filaments tightly woven together, carbon fiber exhibits an extraordinary combination of properties that make it a material of choice for high-performance and lightweight applications. This versatile material has captured the imagination of engineers, designers, and innovators worldwide, pushing the boundaries of what is possible in terms of strength, durability, and weight reduction.
What are carbon fibers?
Carbon Fiber is a polymer ( sometimes known as graphite fiber), it is about thin, strong crystalline filaments of carbon, each fiber is about 5 to 10 micrometers in diameter, carbon atoms bonded together in long chains.
Note that:
- Carbon fiber is 5 times stronger than steel
What are the properties of carbon fiber?
Carbon fiber possess a special properties:
- High stiffness and stiffness-to-weight ratio.
- High tensile strength and strength-to-weight ratio.
- High-temperature tolerance and low thermal expansion.
- High chemical resistance.
1. High Stiffness and Stiffness-to-Weight Ratio
- Carbon fiber is renowned for its exceptional stiffness, which is measured by its modulus of elasticity. It has an incredibly high modulus of elasticity, indicating that it is very resistant to deformation when subjected to external forces. This property makes it ideal for applications where rigidity and stability are crucial.
- The stiffness-to-weight ratio of carbon fiber is also outstanding. This means that it offers high levels of stiffness for its relatively low weight. In practical terms, this property allows for the construction of lightweight structures that maintain their shape and resist bending or flexing under load.
2. High Tensile Strength and Strength-to-Weight Ratio
- Carbon fiber possesses an impressive tensile strength, which is the maximum stress a material can withstand while being stretched or pulled. Carbon fiber's tensile strength is significantly greater than that of materials like steel.
- The strength-to-weight ratio of carbon fiber is another critical advantage. It means that carbon fiber can provide high levels of strength while keeping the overall weight of a structure or component low. This property is particularly valuable in applications where weight savings are essential, such as aerospace and automotive industries.
3. High-Temperature Tolerance and Low Thermal Expansion
- Carbon fiber exhibits a high resistance to heat, making it suitable for applications in high-temperature environments. It retains its mechanical properties at elevated temperatures much better than many other materials, including metals.
- Additionally, carbon fiber has a low coefficient of thermal expansion. This means that it expands or contracts very little with changes in temperature. Low thermal expansion is beneficial in applications where dimensional stability is critical, as it minimizes the risk of warping or distortion due to temperature fluctuations.
4. High Chemical Resistance
- Carbon fiber is generally chemically inert, meaning it does not react with most chemicals. This property makes it highly resistant to corrosion and degradation when exposed to a wide range of chemical substances.
- Its chemical resistance is especially valuable in industries like chemical processing, where equipment needs to withstand contact with aggressive chemicals and acids without deteriorating.
In addition to some other distinguishing properties:
5. Excellent Fatigue Resistance
- Carbon fiber exhibits excellent fatigue resistance, meaning it can withstand repeated loading and unloading without experiencing significant degradation in performance.
6. Versatility
- Carbon fiber can be molded and shaped into various forms and combined with other materials like resins to create composites with specific properties tailored to different applications.
7. Electrical Conductivity
- Carbon fiber is typically electrically conductive. However, it can be engineered to be electrically insulating by using different types of carbon fiber or coatings, making it suitable for a wide range of electronic and electrical applications.
What is carbon fiber made of?
Carbon fiber produced by using raw materials called precursor. About 90% of the carbon fibers are made from polyacrylonitrile PAN (is a synthetic, semi crystalline organic polymer resin with the linear formula (CH2CHCN)n), the remaining percentage are made from rayon or petroleum pitch (a residue from heat treatment and distillation of petroleum fractions). These raw materials are organic polymers, characterized by long strings of molecules bound together by carbon atoms. The specific makeup of each precursor differs between companies and is typically regarded as proprietary information.
Carbon fiber composite
To use carbon fiber in different applications it should be a composite, kind of the composite differ according to the kind of use or application.
Carbon fibers are commonly utilized in combination with other substances to create composites ( it must be supported in a stable matrix ). One such composite is carbon fiber reinforced polymer, which results from impregnating the fibers with a plastic resin (like epoxy) and then subjecting them to baking. This composite boasts an exceptionally high strength-to-weight ratio, rendering it remarkably rigid, albeit somewhat brittle. Additionally, carbon fibers are combined with materials like graphite to produce reinforced carbon-carbon composites, known for their exceptional heat tolerance.
For example, carbon fibers provide strength, and epoxy resin is a great material with high physical qualities, is frequently utilized for this matrix.
Epoxy and carbon fiber are both low-density materials, making it possible to produce a product that is both light and robust.
There are numerous techniques that can be used to fabricate a composite product, including wet-layup, vacuum bagging, resin transfer, matched tooling, insert molding, pultrusion, and many others. Additionally, the choice of resin enables customization of particular qualities like high temperature or chemical resistance.
The epoxy is just an example for the materials which can use with carbon fiber to form a composite.
You can know the actual process of manufacturing from Carbon fiber manufacturing.
What is the difference between carbon fibers and glass fibers?
Carbon fibers and glass fibers are both types of fibers used in composites, but they differ significantly in their composition and properties.
Composition:
Carbon fibers are composed primarily of carbon atoms aligned in a crystalline structure. They are derived from organic polymers, such as polyacrylonitrile (PAN) or petroleum pitch, which are processed through high-temperature treatments to form the carbon fibers.
Glass fibers, on the other hand, are made from molten glass that is extruded into fine fibers. The glass used in making these fibers is usually a combination of silica, limestone, alumina, and other minerals.
Mechanical Properties:
Carbon fibers have an outstanding strength-to-weight ratio and are incredibly stiff. They exhibit high tensile strength and modulus, making them ideal for applications requiring lightweight and high-performance materials.
Glass fibers are less strong and stiff compared to carbon fibers but still possess good mechanical properties. They offer excellent tensile strength but are generally more flexible than carbon fibers.
Weight:
Carbon fibers are significantly lighter than glass fibers due to their composition of almost pure carbon. This property contributes to the overall lightweight nature of carbon-fiber-reinforced composites.
Glass fibers are denser compared to carbon fibers because of their glass composition, which can result in composites that are relatively heavier.
Electrical Conductivity:
Carbon fibers are electrically conductive due to the presence of carbon atoms, allowing them to dissipate electrical charges. This property is beneficial in applications where electrical conductivity is required.
Glass fibers, being made of insulating materials like glass, are non-conductive and do not dissipate electrical charges.
Cost:
Carbon fibers are generally more expensive to produce compared to glass fibers. The manufacturing process of carbon fibers involves complex high-temperature treatments, contributing to their higher cost.
Glass fibers are more cost-effective to produce, making them a common choice for various applications where high-performance requirements are not as critical.
- Glass fiber
In summary, carbon fibers excel in high-performance applications that demand exceptional strength, stiffness, and lightweight properties. Glass fibers, on the other hand, are a more economical option suitable for applications that do not require the same level of performance as carbon fibers. The choice between the two depends on the specific needs and constraints of the intended application.
What is carbon fiber used for? (Carbon fiber uses)
Aerospace: Carbon fiber is extensively used in the aerospace industry for manufacturing aircraft components, such as wings, fuselage parts, and tail sections. Its lightweight nature helps reduce the overall weight of aircraft, leading to improved fuel efficiency and performance.
Automotive: In the automotive sector, carbon fiber in cars is employed to produce lightweight body panels, chassis components, and interior parts. Using carbon fiber in vehicles can enhance their fuel efficiency, handling, and acceleration.
Automotive: In the automotive sector, carbon fiber in cars is employed to produce lightweight body panels, chassis components, and interior parts. Using carbon fiber in vehicles can enhance their fuel efficiency, handling, and acceleration.
Sports and Recreation: Carbon fiber is widely used in sports and recreational equipment, such as bicycles, tennis rackets, golf clubs, hockey sticks, and fishing rods. The material's high stiffness and strength contribute to better performance in these applications.
Wind Energy: Carbon fiber plays a crucial role in the manufacturing of wind turbine blades. Its strength and fatigue resistance make it an ideal choice for withstanding the stresses and loads experienced by wind turbine blades during operation.
Marine: In the marine industry, carbon fiber is utilized to build lightweight yet robust boat hulls, masts, and sail structures. It helps improve the speed and handling of boats and yachts.
Construction: Carbon fiber reinforced polymers (CFRP) are used in the construction of buildings and bridges to reinforce structures and increase their load-carrying capacity. CFRP composites offer high strength and durability.
Industrial Applications: Carbon fiber finds applications in various industrial settings, such as robotics, automation, and equipment manufacturing. It is used for creating lightweight and strong robotic arms, machine parts, and other industrial components.
Medical Devices: Carbon fiber is used in medical devices and equipment, including wheelchairs, prosthetics, and orthopedic supports, owing to its lightweight and strong characteristics.
Defense: In the defense sector, carbon fiber is employed in manufacturing military equipment, including aircraft components, armor, and missiles, to enhance performance and reduce weight.
Consumer Goods: Carbon fiber is also utilized in consumer products like luxury goods, smartphone cases, and high-end furniture, where the material's aesthetics and performance are valued.
Wind Energy: Carbon fiber plays a crucial role in the manufacturing of wind turbine blades. Its strength and fatigue resistance make it an ideal choice for withstanding the stresses and loads experienced by wind turbine blades during operation.
Marine: In the marine industry, carbon fiber is utilized to build lightweight yet robust boat hulls, masts, and sail structures. It helps improve the speed and handling of boats and yachts.
Construction: Carbon fiber reinforced polymers (CFRP) are used in the construction of buildings and bridges to reinforce structures and increase their load-carrying capacity. CFRP composites offer high strength and durability.
Industrial Applications: Carbon fiber finds applications in various industrial settings, such as robotics, automation, and equipment manufacturing. It is used for creating lightweight and strong robotic arms, machine parts, and other industrial components.
Medical Devices: Carbon fiber is used in medical devices and equipment, including wheelchairs, prosthetics, and orthopedic supports, owing to its lightweight and strong characteristics.
Defense: In the defense sector, carbon fiber is employed in manufacturing military equipment, including aircraft components, armor, and missiles, to enhance performance and reduce weight.
Consumer Goods: Carbon fiber is also utilized in consumer products like luxury goods, smartphone cases, and high-end furniture, where the material's aesthetics and performance are valued.
