The new buzzword in the manufacturing world is “continuous carbon fiber.” More companies are now shifting to carbon fiber-based products. Additive manufacturing or 3D printing processes have also, very recently, started incorporating the usage of continuous carbon fibers. It is not wrong to say that continuous carbon fiber has a promising future.
In manufacturing, there is always a requirement of getting superior physical & mechanical properties. Carbon fiber is known to provide irrefutable strength, stiffness, high heat resistance, fine surface texture, and theoretically infinite fatigue life. This is why carbon fiber can be a worthy substitute for some of the expensive traditional materials like — aluminum, steel, iron, etc.
To understand what makes carbon fiber worthy of adoption across various manufacturing industries, this article will focus on the following areas.
- What is carbon fiber?
- How carbon fiber is replacing traditional materials
- What makes continuous carbon fiber in 3D printing suitable for manufacturing?
- Where do we use continuous carbon fibers in today’s world
What is carbon fiber?
Carbon fibers are about 5 to 10 micrometers in diameter. They are composed of carbon atoms. Lately, it is gaining popularity across various sectors, especially in the manufacturing fields.
Here is why carbon fiber is unique and can be considered a great replacement for traditional materials :
- High Stiffness: Carbon fibers do not lose their shape when put under high stress. In other words, the deflection in a given load is very small compared to any other material
- High heat resistance: Unlike other materials such as PLA or ABS, carbon fibers provide high heat resistance. Hence, it is often mixed with these substances to cover up for their shortcomings.
- Strength: It gives a good strength-to-weight ratio which allows quality performance even with low density
- Lightweight: This key feature allows a significant weight reduction in the production of certain products.
- Corrosion resistance — Carbon fiber-based components are not susceptible to rust when compared to their metal counterparts
- Higher fatigue life — when compared to metals, carbon fibers have higher fatigue life.
Carbon fiber is popularly used as reinforcements to make what we call composite materials. Composite materials are versatile when it comes to their physical and chemical properties. Materials are combined to form composites to attain the desired property. The user has a choice and selection with regards to the behavior and activity of the material. For example, carbon fibers are often combined with materials such as — PLA (polylactic acid) and ABS (acrylonitrile butadiene styrene) to improve the mechanical properties of the plastic bases.
Let’s take a closer look at the image above. It is a toothed belt that is used in photocopiers, sewing machines, automobiles (inside the motorcycle engines), etc. Traditionally, these are made using rubbers which over time lead to a lot of wear and tear. Therefore, reinforce carbon fibers are a great substitute giving the belt strength without compromising on the mechanical properties. The advantages of carbon fibers are limitless when it comes to applications in the manufacturing industries.
Here is why carbon fibers are replacing traditional materials
1. High strength-to-weight ratio
When compared to materials like steel or aluminum continuous carbon fiber composites weigh 25%-60% less. Also, the strength and stiffness are irrefutable. Especially, in automobile industries where the weight of the vehicles is a primary focal point, the use of continuous carbon fibers helps in weight reduction. Also, carbon fibers can be formed into thin layers of sheets. This improves the strength when compared to single-layered sheets.
High-end auto engineers use composites to decrease vehicle weight by as much as 60% while improving crash safety
Carbon fiber-based components are not susceptible to rust when compared to their metal counterparts. Regardless of the weather, carbon fiber-infused materials tend to keep their shape with changing temperatures. Helicopter or turbine blades are made out of carbon fiber-based material. This ensures durability. Other materials demand replacements over a short span of time.
3. Easy to design, prototype & manufacture (3D printing)
When it comes to 3D printing, material selection is crucial in the design phase of the project. Continuous carbon fiber being lightweight is a go-to material to achieve this goal for most manufacturers. Its physical properties also give designers various options when it comes to nailing their ideas.
The prototyping or manufacturing phase takes up a considerable amount of time in production. Time-consuming lay-up processes in past were used to achieve the desired shape of the geometry. With the help of digital composite manufacturing, it is now possible to fast-track the process by a great deal. It enables the usage of 3D printing to produce products with the required strength and density.
When it comes to using carbon fiber, most industrial techniques face difficulties in terms of cost and production time. However, additive manufacturing techniques like 3D printing can incorporate carbon fibers in various forms.
What makes continuous carbon fiber in 3D printing suitable for manufacturing?
Carbon fiber has a huge role to play in additive manufacturing. 3D printing using carbon fiber is a common practice. For 3D printing carbon fiber can be used in two forms — chopped and continuous.
The chopped carbon fiber filaments are tiny scrapes that are mixed and added to the base substances like PLA or ABS. They offer improved mechanical resistance and strength.
A continuous fiber has a high length to diameter ratio making them stiffer. It is claimed to be five times stronger and one-third lighter in weight when compared to steel in its fiber form. Continuous carbon fiber is also used for 3D printing. The entire process is referred to as continuous fiber fabrication. In comparison to chopped carbon fiber, continuous fiber is capable of absorption and distribution of load across the entire length.
“Chopped fibers simply fill the material matrix without any orientation while continuous fibers run end to end being oriented in the same direction” — 3dprintingindustry.com
In continuous carbon fiber 3D printing, the thermoplastic extrudes and creates an infill. Then the continuous fiber is poured into the infill (combining the carbon fiber with the thermoplastic). Layer by layer the printing is carried out over several rounds of repetition.
Continuous carbon fiber is used for 3D printing for the production of bike frames, aircraft wings, automotive drive shafts, containers, propeller blades, and car components.
Where do we use continuous carbon fibers in today’s world
As established earlier, carbon fiber-based materials are lightweight and high in strength. This is why they play a crucial role in drone manufacturing. With the help of carbon fiber properties, drones can now fly greater distances with increased flight time due to the significant reduction in drone weight. This also improves the energy utilization and fuel efficiency of drone engines. Carbon fiber is used in various drone parts like — frames, plates, tubes to achieve lightweight and rigidity to improve its performance.
Facebook has invested in the development of a drone named — Aquila. It is a carbon fiber composite-based, solar-powered, four-propeller drone. It was tested in 2016 where it flew for the duration of 96 minutes (altitude 305m) and the next year to flew for 106 minutes (914.4m). The weight of this drone is 400kg, which is less than 1/5th of the currently used — Reaper drone. This accounts for a significant weight reduction by using carbon fiber.
Any object that flies (like drones) is highly dependent on its structural design and weight for high performance. Similarly, airplanes and helicopters have a great potential to incorporate continuous carbon fibers. Airliners like Airbus, Boeing also use Continous Carbon Fiber extensively in passenger aircraft.
Air Force Research Laboratory (USA Air force) has recently delivered low-cost, carbon fiber spars of an LCAA (Low-cost attribute aircraft) wing assembly. It uses continuous fiber 3D printing (CF3D)technology to develop this lightweight wing assembly. The new structure had an improved performance of 160% design limit load.
“The successful work with Continuous Carbon fiber Composites and AFRL’s focus on CF3D for this project not only advances new 3D printing technology but also offers the potential for aerospace-grade composite printing in high-performance industries,”
– John Scarcello, Senior Manager at Lockheed Martin Skunk Works.
Continuous carbon fiber materials are used frequently in high-end and luxury vehicles which improve fuel efficiency and speed. Many car manufacturers such as BMW uses carbon fiber chassis elements. From different body components to structural components, carbon fibers are used in automotive industries more than ever. A significant reduction in fuel consumption also helps in controlling CO2 emissions. This can help with bringing down the carbon footprint.
“Components made of visible carbon, with the fabric structure that is so characteristic of this material, are visually fascinating. Fans of the high-tech material get their money’s worth with BMW M Performance Parts”
Other than lightweight components, it also helps in creating parts that are corrosion resistant. Thereby, increasing the longevity of the vehicle. Moreover, carbon fibers can give a great finish. This enhances the look and feel of the car.
A relatively new entrant to the carbon fiber world — Sports industries are not shying away from using continuous carbon fibers for their sporting goods. Lightweight, sturdy equipment is taking sports to the next level. Various sports have products built using continuous carbon fiber composites —
- Tennis/ Badminton — rackets and frames
- Golf — clubs handles
- Cycling — frames of bikes
- Skiing — stiff carbon fiberboard
- Skating – helmets, skates
- Water sports — canoes, kayaks, paddles
More and more industries are now getting on board to explore the possibilities of improving the design and product quality with help of continuous carbon fibers. Certain properties of carbon fibers put it ahead of the traditional materials like — aluminum, steel, etc. With the help of carbon fibers, manufacturers get great versatility to a selection of the required chemical/physical properties.
- Continuous carbon fiber is lightweight
- It has high strength and durability
- Offers high thermal/chemical resistance
- Its stiffness can be used to replace heavy metals
The qualities of continuous carbon fibers can not go unnoticed by manufacturers who wish to deliver high-performance, quality products to their customers. The capabilities of carbon fibers are very unique. Therefore, it is not ambitious to say that carbon fibers will continue to replace traditional materials across various industries in near future. We hope that this article touch bases with some of the possibilities that carbon fibers exhibit.
Please let us know what you think about carbon fibers in the comments below.